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Sample records for superior sulfur sorbent

  1. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID REMOVAL

    Energy Technology Data Exchange (ETDEWEB)

    Gary M. Blythe

    2004-01-01

    The objective of this project has been to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The project was co-funded by the U.S. DOE National Energy Technology Laboratory under Cooperative Agreement DE-FC26-99FT40718, along with EPRI, the American Electric Power Company (AEP), FirstEnergy Corporation, the Tennessee Valley Authority, and Carmeuse North America. Sulfuric acid controls are becoming of increased interest for coal-fired power generating units for a number of reasons. In particular, sulfuric acid can cause plant operation problems such as air heater plugging and fouling, back-end corrosion, and plume opacity. These issues will likely be exacerbated with the retrofit of selective catalytic reduction (SCR) for NOX control, as SCR catalysts are known to further oxidize a portion of the flue gas SO{sub 2} to SO{sub 3}. The project tested the effectiveness of furnace injection of four different magnesium-based or dolomitic alkaline sorbents on full-scale utility boilers. These reagents were tested during one- to two-week tests conducted on two FirstEnergy Bruce Mansfield Plant (BMP) units. One of the sorbents tested was a magnesium hydroxide slurry byproduct from a modified Thiosorbic{reg_sign} Lime wet flue gas desulfurization process. The other three sorbents are available commercially and include dolomite, pressure-hydrated dolomitic lime, and commercially available magnesium hydroxide. The dolomite reagent was injected as a dry powder through out-of-service burners. The other three reagents were injected as slurries through air-atomizing nozzles inserted through the front wall of the upper furnace. After completing the four one- to two-week tests, the most promising sorbents were selected for longer-term (approximately 25-day) full-scale tests on two different units. The longer-term tests were conducted to confirm sorbent effectiveness over extended operation on two

  2. Experimental evaluation of sorbents for sulfur control in a coal-fueled gas turbine slagging combustor

    International Nuclear Information System (INIS)

    Cowell, L.H.; Wen, C.S.; LeCren, R.T.

    1992-01-01

    This paper reports on a slagging combustor that has been used to evaluate three calcium-based sorbents for sulfur capture efficiency in order to assess their applicability for use in a oil-fueled gas turbine. Testing is competed in a bench-scale combustor with one-tenth the heat input needed for the full-scale gas turbine. The bench-scale rig is a two-stage combustor featuring a fuel-rich primary zone an a fuel-lean secondary zone. The combustor is operated at 6.5 bars with inlet air preheated to 600 K. Gas temperatures of 1840 K are generated in the primary zone and 1280 K in the secondary zone. Sorbents are either fed into the secondary zone or mixed with the coal-water mixture and fed into the primary zone. Dry powered sorbents are fed into the secondary zone by an auger into one of six secondary air inlet ports. The three sorbents tested in the secondary zone include dolomite, pressure-hydrated dolomitic lime, and hydrated lime. Sorbents have been tested while burning coal-water mixtures with coal sulfur loadings of 0.56 to 3.13 weight percent sulfur. Sorbents are injected into the secondary zone at varying flow rates such that the calcium/sulfur ratio varies from 0.5 to 10.0

  3. Effect of characteristic of sorbents on their sulfur capture capability at a fluidized bed condition

    Energy Technology Data Exchange (ETDEWEB)

    Leming Cheng; Bo Chen; Ni Liu; Zhongyang Luo; Kefa Cen [Zhejiang University, Hangzhou (China). Clean Energy and Environment Engineering Key Lab of Ministry of Education, Institute for Thermal Power Engineering

    2004-05-01

    This research was intent for finding relationships among physical and/or chemical properties of sorbents and their sulfur capture capability at a fluidized bed condition. Three limestones and two seashells were chosen as a SO{sub 2} sorbent. Characteristics of sorbents were evaluated based on atomic absorption spectrophotometer, scanning electron microscope and mercury-penetration porosimeter analyses. Their sulfur capture capabilities were measured on a fluidized bed test system at 800, 850, 900 and 950{sup o}C. Conversion of the sobents was computed and analyzed depending on the sorbents' morphology and microstructure analysis. Results showed pore size and specific surface might have large influence on sorbents' desulfurization ability in the range of 800 950{sup o}C. 14 refs., 6 figs., 4 tabs.

  4. FURNACE INJECTION OF ALKALINE SORBENTS FOR SULFURIC ACID CONTROL; SEMIANNUAL

    International Nuclear Information System (INIS)

    Gary M. Blythe

    2002-01-01

    This document summarizes progress on Cooperative Agreement DE-FC26-99FT40718, Furnace Injection of Alkaline Sorbents for Sulfuric Acid Control, during the time period October 1, 2001 through March 31, 2002. The objective of this project is to demonstrate the use of alkaline reagents injected into the furnace of coal-fired boilers as a means of controlling sulfuric acid emissions. The coincident removal of hydrochloric acid and hydrofluoric acid is also being determined, as is the removal of arsenic, a known poison for NO(sub X) selective catalytic reduction (SCR) catalysts. EPRI, the Tennessee Valley Authority (TVA), FirstEnergy Corporation, American Electric Power (AEP) and the Dravo Lime Company are project co-funders. URS Corporation is the prime contractor. This is the fifth reporting period for the subject Cooperative Agreement. During the previous (fourth) period, two long-term sorbent injection tests were conducted, one on Unit 3 at FirstEnergy's Bruce Mansfield Plant (BMP) and one on Unit 1 at AEP's Gavin Plant. Those tests determined the effectiveness of injecting alkaline slurries into the upper furnace of the boiler as a means of controlling sulfuric acid emissions from these units. The alkaline slurries tested included commercially available magnesium hydroxide slurry (Gavin Plant) and a byproduct magnesium hydroxide slurry (at both Gavin and BMP). The tests showed that injecting either the commercial or the byproduct magnesium hydroxide slurry could achieve up to 70-75% overall sulfuric acid removal. At BMP, the overall removal was limited by the need to maintain acceptable electrostatic precipitator (ESP) particulate control performance. At Gavin Plant, the overall sulfuric acid removal was limited because the furnace injected sorbent was less effective at removing SO(sub 3) formed across the SCR system installed on the unit for NO(sub X) control than at removing SO(sub 3) formed in the furnace. The SO(sub 3) removal results were presented in the

  5. Long Life Moving-Bed Zinc Titanate Sorbent

    International Nuclear Information System (INIS)

    Copeland, Robert J.; Cesario, Mike; Feinberg, Daniel A.; Sibold, Jack; Windecker, Brian; Yang, Jing

    1997-01-01

    The objective of this work was to develop and test long-life sorbents for hot gas cleanup. Specifically, we measured the sulfur loading at space velocities typically used for absorption of H 2 S and regenerated the sorbent with diluted air for multiple cycles. Based on the experimental results, we prepared a conceptual design of the sorbent-fabrication system, and estimated the cost of sorbent production and of sulfur removal

  6. Production of ultra-low-sulfur gasoline: an equilibrium and kinetic analysis on adsorption of sulfur compounds over Ni/MMS sorbents.

    Science.gov (United States)

    Subhan, Fazle; Liu, B S; Zhang, Q L; Wang, W S

    2012-11-15

    High performance nickel-based micro-mesoporous silica (Ni/MMS) sorbent was prepared by incipient wetness impregnation with ultrasonic aid (IWI-u) for adsorptive desulfurization (ADS) of commercial gasoline and simulated fuels. The sorbents were characterized with BET, XRD, TPR, SEM, HRTEM and TG/DTG. These results show that 20 wt%Ni/MMS (IWI-u) can still retain the framework of MMS and nickel particles were homogeneously distributed in the MMS channels without any aggregation, which improved significantly the ADS performance of the sorbents. The studies on the ADS kinetics indicate that the adsorption behavior of thiophene (T), benzothiophene (BT) and dibenzothiophene (DBT) over 20 wt%Ni/MMS (IWI-u) can be described appropriately by pseudo second-order kinetic model. The intraparticle diffusion model verified that the steric hindrance and intraparticle diffusion were the rate controlling step of the adsorption process of DBT molecules. Langmuir model can be used to describe the adsorption isotherms for T, BT and DBT due to low coverage. The regeneration sorbent maintains the sulfur removal efficiency of 85.9% for 6 cycles. Copyright © 2012 Elsevier B.V. All rights reserved.

  7. Laying Waste to Mercury: Inexpensive Sorbents Made from Sulfur and Recycled Cooking Oils

    Science.gov (United States)

    Worthington, Max J. H.; Kucera, Renata L.; Albuquerque, Inês S.; Gibson, Christopher T.; Sibley, Alexander; Slattery, Ashley D.; Campbell, Jonathan A.; Alboaiji, Salah F. K.; Muller, Katherine A.; Young, Jason; Adamson, Nick; Gascooke, Jason R.; Jampaiah, Deshetti; Sabri, Ylias M.; Bhargava, Suresh K.; Ippolito, Samuel J.; Lewis, David A.; Quinton, Jamie S.; Ellis, Amanda V.; Johs, Alexander; Bernardes, Gonçalo J. L.

    2017-01-01

    Abstract Mercury pollution threatens the environment and human health across the globe. This neurotoxic substance is encountered in artisanal gold mining, coal combustion, oil and gas refining, waste incineration, chloralkali plant operation, metallurgy, and areas of agriculture in which mercury‐rich fungicides are used. Thousands of tonnes of mercury are emitted annually through these activities. With the Minamata Convention on Mercury entering force this year, increasing regulation of mercury pollution is imminent. It is therefore critical to provide inexpensive and scalable mercury sorbents. The research herein addresses this need by introducing low‐cost mercury sorbents made solely from sulfur and unsaturated cooking oils. A porous version of the polymer was prepared by simply synthesising the polymer in the presence of a sodium chloride porogen. The resulting material is a rubber that captures liquid mercury metal, mercury vapour, inorganic mercury bound to organic matter, and highly toxic alkylmercury compounds. Mercury removal from air, water and soil was demonstrated. Because sulfur is a by‐product of petroleum refining and spent cooking oils from the food industry are suitable starting materials, these mercury‐capturing polymers can be synthesised entirely from waste and supplied on multi‐kilogram scales. This study is therefore an advance in waste valorisation and environmental chemistry. PMID:28763123

  8. Novel Sorbent to Clean Up Biogas for CHPs

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gökhan O. [TDA Research, Incorporated, Wheat Ridge, CO (United States); Jayataman, Ambalavanan [TDA Research, Incorporated, Wheat Ridge, CO (United States); Schaefer, Matthew [TDA Research, Incorporated, Wheat Ridge, CO (United States); Ware, Michael [TDA Research, Incorporated, Wheat Ridge, CO (United States); Hunt, Jennifer [FuelCell Energy, Inc., Danbury, CT (United States); Dobek, Frank [FuelCell Energy, Inc., Danbury, CT (United States)

    2015-05-30

    In this project, TDA Research Inc. (TDA) has developed low-cost (on a per unit volume of gas processed basis), high-capacity expendable sorbents that can remove both the H2S and organic sulfur species in biogas to the ppb levels. The proposed sorbents will operate downstream of a bulk desulfurization system as a polishing bed to provide an essentially sulfur-free gas to a fuel cell (or any other application that needs a completely sulfur-free feed). Our sorbents use a highly dispersed mixed metal oxides active phase with desired modifiers prepared over on a mesoporous support. The support structure allows the large organic sulfur compounds (such as the diethyl sulfide and dipropyl sulfide phases with a large kinetic diameter) to enter the sorbent pores so that they can be adsorbed and removed from the gas stream.

  9. Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas

    Energy Technology Data Exchange (ETDEWEB)

    Carl Richardson; Katherine Dombrowski; Douglas Orr

    2006-12-31

    This project Final Report is submitted to the U.S. Department of Energy (DOE) as part of Cooperative Agreement DE-FC26-03NT41987, 'Sorbent Injection for Small ESP Mercury Control in Low Sulfur Eastern Bituminous Coal Flue Gas.' Sorbent injection technology is targeted as the primary mercury control process on plants burning low/medium sulfur bituminous coals equipped with ESP and ESP/FGD systems. About 70% of the ESPs used in the utility industry have SCAs less than 300 ft2/1000 acfm. Prior to this test program, previous sorbent injection tests had focused on large-SCA ESPs. This DOE-NETL program was designed to generate data to evaluate the performance and economic feasibility of sorbent injection for mercury control at power plants that fire bituminous coal and are configured with small-sized electrostatic precipitators and/or an ESP-flue gas desulfurization (FGD) configuration. EPRI and Southern Company were co-funders for the test program. Southern Company and Reliant Energy provided host sites for testing and technical input to the project. URS Group was the prime contractor to NETL. ADA-ES and Apogee Scientific Inc. were sub-contractors to URS and was responsible for all aspects of the sorbent injection systems design, installation and operation at the different host sites. Full-scale sorbent injection for mercury control was evaluated at three sites: Georgia Power's Plant Yates Units 1 and 2 [Georgia Power is a subsidiary of the Southern Company] and Reliant Energy's Shawville Unit 3. Georgia Power's Plant Yates Unit 1 has an existing small-SCA cold-side ESP followed by a Chiyoda CT-121 wet scrubber. Yates Unit 2 is also equipped with a small-SCA ESP and a dual flue gas conditioning system. Unit 2 has no SO2 control system. Shawville Unit 3 is equipped with two small-SCA cold-side ESPs operated in series. All ESP systems tested in this program had SCAs less than 250 ft2/1000 acfm. Short-term parametric tests were conducted on Yates

  10. Advanced sorbent development progam; development of sorbents for moving-bed and fluidized-bed applications

    International Nuclear Information System (INIS)

    Ayala, R.E.; Venkataramani, V.S.

    1998-01-01

    The integrated gasification combined cycle (IGCC) power system using high-temperature coal gas cleanup is one of the most promising advanced technologies for the production of electric power from coal in an environmentally acceptable manner. Unlike conventional low-temperature cleanup systems that require costly heat exchangers, high-temperature coal gas cleanup systems can be operated near 482-538 C (900-1000F) or higher, conditions that are a closer match with the gasifier and turbine components in the IGCC system, thus resulting is a more efficient overall system. GE is developing a moving-bed, high-temperature desulfurization system for the IGCC power cycle in which zinc-based regenerable sorbents are currently being used as desulfurization sorbents. Zinc titanate and other proprietary zinc-based oxides are being considered as sorbents for use in the Clean Coal Technology Demonstration Program at Tampa Electric Co.s (TECo) Polk Power Station. Under cold startup conditions at TECo, desulfurization and regeneration may be carried out at temperatures as low as 343 C (650 F), hence a versatile sorbent is desirable to perform over this wide temperature range. A key to success in the development of high-temperature desulfurization systems is the matching of sorbent properties for the selected process operating conditions, namely, sustainable desulfurization kinetics, high sulfur capacity, and mechanical durability over multiple cycles. Additionally, the sulfur species produced during regeneration of the sorbent must be in a form compatible with sulfur recovery systems, such as sulfuric acid or elemental sulfur processes. The overall objective of this program is to develop regenerable sorbents for hydrogen sulfide removal from coal-derived fuel gases in the temperature range 343-538 C (650-1000 F). Two categories of reactor configurations are being considered: moving-bed reactors and fluidized-bed (bubbling and circulating) reactors. In addition, a cost assessment and

  11. Laying Waste to Mercury: Inexpensive Sorbents Made from Sulfur and Recycled Cooking Oils.

    Science.gov (United States)

    Worthington, Max J H; Kucera, Renata L; Albuquerque, Inês S; Gibson, Christopher T; Sibley, Alexander; Slattery, Ashley D; Campbell, Jonathan A; Alboaiji, Salah F K; Muller, Katherine A; Young, Jason; Adamson, Nick; Gascooke, Jason R; Jampaiah, Deshetti; Sabri, Ylias M; Bhargava, Suresh K; Ippolito, Samuel J; Lewis, David A; Quinton, Jamie S; Ellis, Amanda V; Johs, Alexander; Bernardes, Gonçalo J L; Chalker, Justin M

    2017-11-16

    Mercury pollution threatens the environment and human health across the globe. This neurotoxic substance is encountered in artisanal gold mining, coal combustion, oil and gas refining, waste incineration, chloralkali plant operation, metallurgy, and areas of agriculture in which mercury-rich fungicides are used. Thousands of tonnes of mercury are emitted annually through these activities. With the Minamata Convention on Mercury entering force this year, increasing regulation of mercury pollution is imminent. It is therefore critical to provide inexpensive and scalable mercury sorbents. The research herein addresses this need by introducing low-cost mercury sorbents made solely from sulfur and unsaturated cooking oils. A porous version of the polymer was prepared by simply synthesising the polymer in the presence of a sodium chloride porogen. The resulting material is a rubber that captures liquid mercury metal, mercury vapour, inorganic mercury bound to organic matter, and highly toxic alkylmercury compounds. Mercury removal from air, water and soil was demonstrated. Because sulfur is a by-product of petroleum refining and spent cooking oils from the food industry are suitable starting materials, these mercury-capturing polymers can be synthesised entirely from waste and supplied on multi-kilogram scales. This study is therefore an advance in waste valorisation and environmental chemistry. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  12. Non-carbon sorbents for mercury removal from flue gases

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, G.O.; Dubovik, M.; Cesario, M. [TDA Research Inc., Wheat Ridge, CO (United States)

    2005-07-01

    TDA Research Inc. is developing a new sorbent that can effectively remove mercury from flue gases. It is made of non-carbon based materials and will therefore not alter the properties of the fly ash. The sorbent can be produced as an injectable powder. The paper summarises the initial testing results of the new sorbent. The sorbent exhibited 7.5 to 11.0 mg/g mercury absorption capacity under representative flue gas streams depending on the operating temperature and gas hourly space velocity. The sorbent also showed resistance to sulfur poisoning by sulfur dioxide. 6 refs., 3 figs., 1 tab.

  13. Method of burning sulfur-containing fuels in a fluidized bed boiler

    Science.gov (United States)

    Jones, Brian C.

    1982-01-01

    A method of burning a sulfur-containing fuel in a fluidized bed of sulfur oxide sorbent wherein the overall utilization of sulfur oxide sorbent is increased by comminuting the bed drain solids to a smaller average particle size, preferably on the order of 50 microns, and reinjecting the comminuted bed drain solids into the bed. In comminuting the bed drain solids, particles of spent sulfur sorbent contained therein are fractured thereby exposing unreacted sorbent surface. Upon reinjecting the comminuted bed drain solids into the bed, the newly-exposed unreacted sorbent surface is available for sulfur oxide sorption, thereby increasing overall sorbent utilization.

  14. Solid-Phase Extraction of Sulfur Mustard Metabolites Using an Activated Carbon Fiber Sorbent.

    Science.gov (United States)

    Lee, Jin Young; Lee, Yong Han

    2016-01-01

    A novel solid-phase extraction method using activated carbon fiber (ACF) was developed and validated. ACF has a vast network of pores of varying sizes and microporous structures that result in rapid adsorption and selective extraction of sulfur mustard metabolites according to the pH of eluting solvents. ACF could not only selectively extract thiodiglycol and 1-methylsulfinyl-2-[2-(methylthio)-ethylsulfonyl]ethane eluting a 9:1 ratio of dichloromethane to acetone, and 1,1'-sulfonylbis[2-(methylsulfinyl)ethane] and 1,1'-sulfonylbis- [2-S-(N-acetylcysteinyl)ethane] eluting 3% hydrogen chloride in methanol, but could also eliminate most interference without loss of analytes during the loading and washing steps. A sample preparation method has been optimized for the extraction of sulfur mustard metabolites from human urine using an ACF sorbent. The newly developed extraction method was applied to the trace analysis of metabolites of sulfur mustard in human urine matrices in a confidence-building exercise for the analysis of biomedical samples provided by the Organisation for the Prohibition of Chemical Weapons. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  15. ADVANCED SULFUR CONTROL CONCEPTS

    Energy Technology Data Exchange (ETDEWEB)

    Apostolos A. Nikolopoulos; Santosh K. Gangwal; William J. McMichael; Jeffrey W. Portzer

    2003-01-01

    Conventional sulfur removal in integrated gasification combined cycle (IGCC) power plants involves numerous steps: COS (carbonyl sulfide) hydrolysis, amine scrubbing/regeneration, Claus process, and tail-gas treatment. Advanced sulfur removal in IGCC systems involves typically the use of zinc oxide-based sorbents. The sulfides sorbent is regenerated using dilute air to produce a dilute SO{sub 2} (sulfur dioxide) tail gas. Under previous contracts the highly effective first generation Direct Sulfur Recovery Process (DSRP) for catalytic reduction of this SO{sub 2} tail gas to elemental sulfur was developed. This process is currently undergoing field-testing. In this project, advanced concepts were evaluated to reduce the number of unit operations in sulfur removal and recovery. Substantial effort was directed towards developing sorbents that could be directly regenerated to elemental sulfur in an Advanced Hot Gas Process (AHGP). Development of this process has been described in detail in Appendices A-F. RTI began the development of the Single-step Sulfur Recovery Process (SSRP) to eliminate the use of sorbents and multiple reactors in sulfur removal and recovery. This process showed promising preliminary results and thus further process development of AHGP was abandoned in favor of SSRP. The SSRP is a direct Claus process that consists of injecting SO{sub 2} directly into the quenched coal gas from a coal gasifier, and reacting the H{sub 2}S-SO{sub 2} mixture over a selective catalyst to both remove and recover sulfur in a single step. The process is conducted at gasifier pressure and 125 to 160 C. The proposed commercial embodiment of the SSRP involves a liquid phase of molten sulfur with dispersed catalyst in a slurry bubble-column reactor (SBCR).

  16. Two-step rapid sulfur capture. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1994-04-01

    The primary goal of this program was to test the technical and economic feasibility of a novel dry sorbent injection process called the Two-Step Rapid Sulfur Capture process for several advanced coal utilization systems. The Two-Step Rapid Sulfur Capture process consists of limestone activation in a high temperature auxiliary burner for short times followed by sorbent quenching in a lower temperature sulfur containing coal combustion gas. The Two-Step Rapid Sulfur Capture process is based on the Non-Equilibrium Sulfur Capture process developed by the Energy Technology Office of Textron Defense Systems (ETO/TDS). Based on the Non-Equilibrium Sulfur Capture studies the range of conditions for optimum sorbent activation were thought to be: activation temperature > 2,200 K for activation times in the range of 10--30 ms. Therefore, the aim of the Two-Step process is to create a very active sorbent (under conditions similar to the bomb reactor) and complete the sulfur reaction under thermodynamically favorable conditions. A flow facility was designed and assembled to simulate the temperature, time, stoichiometry, and sulfur gas concentration prevalent in the advanced coal utilization systems such as gasifiers, fluidized bed combustors, mixed-metal oxide desulfurization systems, diesel engines, and gas turbines.

  17. Advanced Byproduct Recovery: Direct Catalytic Reduction of Sulfur Dioxide to Elemental Sulfur.

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-06-01

    More than 170 wet scrubber systems applied, to 72,000 MW of U.S., coal-fired, utility boilers are in operation or under construction. In these systems, the sulfur dioxide removed from the boiler flue gas is permanently bound to a sorbent material, such as lime or limestone. The sulfated sorbent must be disposed of as a waste product or, in some cases, sold as a byproduct (e.g. gypsum). Due to the abundance and low cost of naturally occurring gypsum, and the costs associated with producing an industrial quality product, less than 7% of these scrubbers are configured to produce usable gypsum (and only 1% of all units actually sell the byproduct). The disposal of solid waste from each of these scrubbers requires a landfill area of approximately 200 to 400 acres. In the U.S., a total of 19 million tons of disposable FGD byproduct are produced, transported and disposed of in landfills annually. The use of regenerable sorbent technologies has the potential to reduce or eliminate solid waste production, transportation and disposal. In a regenerable sorbent system, the sulfur dioxide in the boiler flue gas is removed by the sorbent in an adsorber. The S0{sub 2}s subsequently released, in higher concentration, in a regenerator. All regenerable systems produce an off-gas stream from the regenerator that must be processed further in order to obtain a salable byproduct, such as elemental sulfur, sulfuric acid or liquid S0{sub 2}.

  18. Advanced sulfur control concepts for hot gas desulfurization technology

    International Nuclear Information System (INIS)

    1998-01-01

    The objective of this project is to develop a hot-gas desulfurization process scheme for control of H 2 S in HTHP coal gas that can be more simply and economically integrated with known regenerable sorbents in DOE/METC-sponsored work than current leading hot-gas desulfurization technologies. In addition to being more economical, the process scheme to be developed must yield an elemental sulfur byproduct. The Direct Sulfur Recovery Process (DSRP), a leading process for producing an elemental sulfur byproduct in hot-gas desulfurization systems, incurs a coal gas use penalty, because coal gas is required to reduce the SO 2 in regeneration off-gas to elemental sulfur. Alternative regeneration schemes, which avoid coal gas use and produce elemental sulfur, will be evaluated. These include (i) regeneration of sulfided sorbent using SO 2 ; (ii) partial oxidation of sulfided sorbent in an O 2 starved environment; and (iii) regeneration of sulfided sorbent using steam to produce H 2 S followed by direct oxidation of H 2 S to elemental sulfur. Known regenerable sorbents will be modified to improve the feasibility of the above alternative regeneration approaches. Performance characteristics of the modified sorbents and processes will be obtained through lab- and bench-scale testing. Technical and economic evaluation of the most promising processes concept(s) will be carried out

  19. (18)O(2) label mechanism of sulfur generation and characterization in properties over mesoporous Sm-based sorbents for hot coal gas desulfurization.

    Science.gov (United States)

    Liu, B S; Wan, Z Y; Wang, F; Zhan, Y P; Tian, M; Cheung, A S C

    2014-02-28

    Using a sol-gel method, SmMeOx/MCM-41 or SBA-15 (Me=Fe, Co and Zn) and corresponding unsupported sorbents were prepared. The desulfurization performance of these sorbents was evaluated over a fixed-bed reactor and the effects of reaction temperature, feed and sorbent composition on desulfurization performance were studied. Samarium-based sorbents used to remove H2S from hot coal gas were reported for the first time. The results of successive sulfidation/regeneration cycles revealed that SmFeO3/SBA-15 sorbent was suitable for desulfurization of hot coal gas in the chemical industry. The formation of elemental sulfur during both sulfidation and regeneration processes depended strongly on the catalytic action of Sm2O2S species, which was confirmed for the first time via high sensitive time of flight mass spectrometer (TOF-MS) using 6%vol(18)O2/Ar regeneration gas and can reduce markedly procedural complexity. The sorbents were characterized using N2-adsorption, high-resolution transmission electron microscopy (HRTEM), X-ray diffraction (XRD), temperature-programmed reduction of H2 (H2-TPR), thermogravimetry (TG) and time-of-flight mass spectrometry (TOF-MS) techniques. Copyright © 2014 Elsevier B.V. All rights reserved.

  20. ADVANCED SULFUR CONTROL CONCEPTS FOR HOT-GAS DESULFURIZATION TECHNOLOGY

    Energy Technology Data Exchange (ETDEWEB)

    A. LOPEZ ORTIZ; D.P. HARRISON; F.R. GROVES; J.D. WHITE; S. ZHANG; W.-N. HUANG; Y. ZENG

    1998-10-31

    This research project examined the feasibility of a second generation high-temperature coal gas desulfurization process in which elemental sulfur is produced directly during the sorbent regeneration phase. Two concepts were evaluated experimentally. In the first, FeS was regenerated in a H2O-O2 mixture. Large fractions of the sulfur were liberated in elemental form when the H2O-O2 ratio was large. However, the mole percent of elemental sulfur in the product was always quite small (<<1%) and a process based on this concept was judged to be impractical because of the low temperature and high energy requirements associated with condensing the sulfur. The second concept involved desulfurization using CeO2 and regeneration of the sulfided sorbent, Ce2O2S, using SO2 to produce elemental sulfur directly. No significant side reactions were observed and the reaction was found to be quite rapid over the temperature range of 500°C to 700°C. Elemental sulfur concentrations (as S2) as large as 20 mol% were produced. Limitations associated with the cerium sorbent process are concentrated in the desulfurization phase. High temperature and highly reducing coal gas such as produced in the Shell gasification process are required if high sulfur removal efficiencies are to be achieved. For example, the equilibrium H2S concentration at 800°C from a Shell gas in contact with CeO2 is about 300 ppmv, well above the allowable IGCC specification. In this case, a two-stage desulfurization process using CeO2 for bulk H2S removal following by a zinc sorbent polishing step would be required. Under appropriate conditions, however, CeO2 can be reduced to non-stoichiometric CeOn (n<2) which has significantly greater affinity for H2S. Pre-breakthrough H2S concentrations in the range of 1 ppmv to 5 ppmv were measured in sulfidation tests using CeOn at 700°C in highly reducing gases, as measured by equilibrium O2 concentration, comparable to the Shell gas. Good sorbent durability was indicated in

  1. Advanced sulfur control concepts for hot-gas desulfurization technology

    International Nuclear Information System (INIS)

    Lopez Ortiz, A.; Harrison, D.P.; Groves, F.R.; White, J.D.; Zhang, S.; Huang, W.N.; Zeng, Y.

    1998-01-01

    This research project examined the feasibility of a second generation high-temperature coal gas desulfurization process in which elemental sulfur is produced directly during the sorbent regeneration phase. Two concepts were evaluated experimentally. In the first, FeS was regenerated in a H2O-O2 mixture. Large fractions of the sulfur were liberated in elemental form when the H2O-O2 ratio was large. However, the mole percent of elemental sulfur in the product was always quite small (<<1%) and a process based on this concept was judged to be impractical because of the low temperature and high energy requirements associated with condensing the sulfur. The second concept involved desulfurization using CeO2 and regeneration of the sulfided sorbent, Ce2O2S, using SO2 to produce elemental sulfur directly. No significant side reactions were observed and the reaction was found to be quite rapid over the temperature range of 500C to 700C. Elemental sulfur concentrations (as S2) as large as 20 mol% were produced. Limitations associated with the cerium sorbent process are concentrated in the desulfurization phase. High temperature and highly reducing coal gas such as produced in the Shell gasification process are required if high sulfur removal efficiencies are to be achieved. For example, the equilibrium H2S concentration at 800C from a Shell gas in contact with CeO2 is about 300 ppmv, well above the allowable IGCC specification. In this case, a two-stage desulfurization process using CeO2 for bulk H2S removal following by a zinc sorbent polishing step would be required. Under appropriate conditions, however, CeO2 can be reduced to non-stoichiometric CeOn (n<2) which has significantly greater affinity for H2S. Pre-breakthrough H2S concentrations in the range of 1 ppmv to 5 ppmv were measured in sulfidation tests using CeOn at 700C in highly reducing gases, as measured by equilibrium O2 concentration, comparable to the Shell gas. Good sorbent durability was indicated in a

  2. Fast-regenerable sulfur dioxide adsorbents for diesel engine emission control

    Science.gov (United States)

    Li, Liyu [Richland, WA; King, David L [Richland, WA

    2011-03-15

    Disclosed herein are sorbents and devices for controlling sulfur oxides emissions as well as systems including such sorbents and devices. Also disclosed are methods for making and using the disclosed sorbents, devices and systems. In one embodiment the disclosed sorbents can be conveniently regenerated, such as under normal exhaust stream from a combustion engine, particularly a diesel engine. Accordingly, also disclosed are combustion vehicles equipped with sulfur dioxide emission control devices.

  3. Mesoporous CuO–ZnO binary metal oxide nanocomposite for decontamination of sulfur mustard

    International Nuclear Information System (INIS)

    Praveen Kumar, J.; Prasad, G.K.; Ramacharyulu, P.V.R.K.; Garg, P.; Ganesan, K.

    2013-01-01

    Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. They were prepared by precipitation pyrolysis method and characterized by means of X-ray diffraction, transmission electron microscopy, nitrogen adsorption, Fourier transform infrared spectroscopy techniques. Obtained data indicated the presence of mesopores with diameter ranging from 2 to 80 nm and the materials exhibited relatively high surface area 86 m 2 g −1 when compared to the individual metal oxide nanoparticles. Reactive sites of mesoporous CuO–ZnO binary metal oxide nanocomposites were studied by infrared spectroscopy technique using pyridine as a probe molecule. These materials demonstrated superior decontamination properties against sulfur mustard when compared to single component metal oxides and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Graphical abstract: Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. These materials demonstrated superior decontamination properties against sulfur mustard and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Highlights: • Preparation of mesoporous CuO–ZnO binary metal oxide nanocomposite. • CuO–ZnO with better surface area was synthesized by precipitation pyrolysis. • Decontamination of HD using mesoporous CuO–ZnO binary metal oxide nanocomposite. • HD decontaminated by elimination and hydrolysis reactions

  4. Mesoporous CuO–ZnO binary metal oxide nanocomposite for decontamination of sulfur mustard

    Energy Technology Data Exchange (ETDEWEB)

    Praveen Kumar, J.; Prasad, G.K., E-mail: gkprasad2001@yahoo.com; Ramacharyulu, P.V.R.K.; Garg, P.; Ganesan, K.

    2013-11-01

    Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. They were prepared by precipitation pyrolysis method and characterized by means of X-ray diffraction, transmission electron microscopy, nitrogen adsorption, Fourier transform infrared spectroscopy techniques. Obtained data indicated the presence of mesopores with diameter ranging from 2 to 80 nm and the materials exhibited relatively high surface area 86 m{sup 2} g{sup −1} when compared to the individual metal oxide nanoparticles. Reactive sites of mesoporous CuO–ZnO binary metal oxide nanocomposites were studied by infrared spectroscopy technique using pyridine as a probe molecule. These materials demonstrated superior decontamination properties against sulfur mustard when compared to single component metal oxides and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Graphical abstract: Mesoporous CuO–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard, a well known chemical warfare agent. These materials demonstrated superior decontamination properties against sulfur mustard and decontaminated it to divinyl sulfide, chloroethyl vinyl sulfide, hemisulfur mustard, etc. - Highlights: • Preparation of mesoporous CuO–ZnO binary metal oxide nanocomposite. • CuO–ZnO with better surface area was synthesized by precipitation pyrolysis. • Decontamination of HD using mesoporous CuO–ZnO binary metal oxide nanocomposite. • HD decontaminated by elimination and hydrolysis reactions.

  5. Development of the advanced coolside sorbent injection process for SO{sub 2}

    Energy Technology Data Exchange (ETDEWEB)

    Withum, J.A.; Maskew, J.T.; Rosenhoover, W.A. [Consol, Inc., Library, PA (United States)] [and others

    1995-11-01

    The goal of this work was to develop a low-capital-cost process capable of over 90% SO{sub 2} removal as an economically attractive option for compliance with the Clean Air Act. The Advanced Coolside Process uses a contactor to simultaneously remove fly ash and saturate the flue gas with water, followed by sorbent injection into the highly humid flue gas and collection of the sorbent by the existing particulate collector High sorbent utilization is achieved by sorbent recycle. The original performance targets of 90% SO{sub 2} removal and 60% sorbent utilization were exceeded in 1000 acfm pilot plant operations using commercial hydrated lime as the only sorbent. Process optimization simplified the process equipment, resulting in significant cost reduction. Recent accomplishments include completion of equipment testing and sorbent optimization, a waste management study, and a long-term performance test. An economic evaluation for the optimized process projects capital costs 55% to 60 % less than those of limestone forced oxidation wet FGD. The projected levelized control cost is 15% to 35% lower than wet FGD (25% lower for a 260 MWe plant burning a 2.5% sulfur coal), depending on plant size and coal sulfur content.

  6. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research Development Center (AMAX R D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  7. Hot coal gas desulfurization with manganese-based sorbents. Final report, September 1992--December 1994

    Energy Technology Data Exchange (ETDEWEB)

    Hepworth, M.T.; Slimane, R.B.

    1994-11-01

    The focus of much current work being performed by the Morgantown Energy Technology Center (METC) of the Department of Energy on hot coal-derived fuel gas desulfurization is in the use of zinc-based sorbents. METC has shown interest in formulating and testing manganese-based pellets as alternative effective sulfur sorbents in the 700 to 1200{degree}C temperature range. To substantiate the potential superiority of Mn-based pellets, a systematic approach toward the evaluation of the desulfurizing power of single-metal sorbents is developed based on thermodynamic considerations. This novel procedure considered several metal-based sorbents and singled out manganese oxide as a prime candidate sorbent capable of being utilized under a wide temperature range, irrespective of the reducing power (determined by CO{sub 2}/CO ratio) of the fuel gas. Then, the thermodynamic feasibility of using Mn-based pellets for the removal of H{sub 2}S from hot-coal derived fuel gases, and the subsequent oxidative regeneration of loaded (sulfided) pellets was established. It was concluded that MnO is the stable form of manganese for virtually all commercially available coal-derived fuel gases. In addition, the objective of reducing the H{sub 2}S concentration below 150 ppMv to satisfy the integrated gasification combined cycle system requirement was shown to be thermodynamically feasible. A novel process is developed for the manufacture of Mn-based spherical pellets which have the desired physical and chemical characteristics required.

  8. Highly stable and regenerable Mn-based/SBA-15 sorbents for desulfurization of hot coal gas

    International Nuclear Information System (INIS)

    Zhang, F.M.; Liu, B.S.; Zhang, Y.; Guo, Y.H.; Wan, Z.Y.; Subhan, Fazle

    2012-01-01

    Highlights: ► A series of mesoporous Cu x Mn y O z /SBA-15 sorbents were fabricated for hot coal gas desulfurization. ► 1Cu9Mn/SBA-15 sorbent with high breakthrough sulfur capacity is high stable and regenerable. ► Utilization of SBA-15 constrained the sintering and pulverization of sorbents. - Abstract: A series of mesoporous xCuyMn/SBA-15 sorbents with different Cu/Mn atomic ratios were prepared by wet impregnation method and their desulfurization performance in hot coal gas was investigated in a fixed-bed quartz reactor in the range of 700–850 °C. The successive nine desulfurization–regeneration cycles at 800 °C revealed that 1Cu9Mn/SBA-15 presented high performance with durable regeneration ability due to the high dispersion of Mn 2 O 3 particles incorporated with a certain amount of copper oxides. The breakthrough sulfur capacity of 1Cu9Mn/SBA-15 observed 800 °C is 13.8 g S/100 g sorbents, which is remarkably higher than these of 40 wt%LaFeO 3 /SBA-15 (4.8 g S/100 g sorbents) and 50 wt%LaFe 2 O x /MCM-41 (5.58 g S/100 g sorbents) used only at 500–550 °C. This suggested that the loading of Mn 2 O 3 active species with high thermal stability to SBA-15 support significantly increased sulfur capacity at relatively higher sulfidation temperature. The fresh and used xCuyMn/SBA-15 sorbents were characterized by means of BET, XRD, XPS, XAES, TG/DSC and HRTEM techniques, confirmed that the structure of the sorbents remained intact before and after hot coal gas desulfurization.

  9. PROCEEDINGS: MULTIPOLLUTANT SORBENT REACTIVITY ...

    Science.gov (United States)

    The report is a compilation of technical papers and visual aids presented by representatives of industry, academia, and government agencies at a workshop on multipollutant sorbent reactivity that was held at EPA's Environmental Research Center in Research Triangle Park, NC, on July 19-20, 1994. There were 16 technical presentations in three sessions, and a panel discussion between six research experts. The workshop was a forum for the exchange of ideas and information on the use of sorbents to control air emissions of acid gases (sulfur dioxide, nitrogen oxides, and hydrogen chloride); mercury and dioxins; and toxic metals, primarily from fossil fuel combustion. A secondary purpose for conducting the workshop was to help guide EPA's research planning activities. A general theme of the workshop was that a strategy of controlling many pollutants with a single system rather than systems to control individual pollutants should be a research goal. Some research needs cited were: hazardous air pollutant removal by flue gas desulfurization systems, dioxin formation and control, mercury control, waste minimization, impact of ash recycling on metals partitioning, impact of urea and sorbents on other pollutants, high temperature filtration, impact of coal cleaning on metals partitioning, and modeling dispersion of sorbents in flue gas. information

  10. Sulfur equilibrium desulfurization of sulfur containing products of combustion

    International Nuclear Information System (INIS)

    Woodroffe, J.A.; Abichandani, J.S.

    1990-01-01

    This patent describes the method for the combustion of a carbon- and sulfur-containing fuel for substantially reducing emission of gaseous sulfur compounds formed during combustion of the fuel in a combustion zone. The zone having one or more fuel inlets and one or more oxidizer inlets, and having a combustion products outlet spaced therefrom, and having one or more inorganic sorbent inlets downstream of the fuel inlet(s) and oxidizer inlet(s) and upstream of the combustion products outlet

  11. Alkaline sorbent injection for mercury control

    Science.gov (United States)

    Madden, Deborah A.; Holmes, Michael J.

    2002-01-01

    A mercury removal system for removing mercury from combustion flue gases is provided in which alkaline sorbents at generally extremely low stoichiometric molar ratios of alkaline earth or an alkali metal to sulfur of less than 1.0 are injected into a power plant system at one or more locations to remove at least between about 40% and 60% of the mercury content from combustion flue gases. Small amounts of alkaline sorbents are injected into the flue gas stream at a relatively low rate. A particulate filter is used to remove mercury-containing particles downstream of each injection point used in the power plant system.

  12. IEA low NOx combustion project Stage III. Low NOx combustion and sorbent injection demonstration projects. V.2

    International Nuclear Information System (INIS)

    Payne, R.

    1991-03-01

    This report summarizes the main results from an IES project concerning the demonstration of low-NO x combustion and sorbent injection as techniques for the control of NO x and SO x emissions from pulverized coal fired utility boilers. The project has built upon information generated in two previous stages of activity, where NO x and SO x control processes were evaluated at both fundamental and pilot-scales. The concept for this stage of the project was for a unique collaboration, where the participating countries (Canada, Denmark and Sweden, together with the United States) have pooled information from full scale boiler demonstrations of low-NO x burner and sorbent injection technologies, and have jointly contributed to establishing a common basis for data evaluation. Demonstration testing was successfully carried out on five wall-fired commercial boiler systems which ranged in size from a 20 MW thermal input boiler used for district heating, up to a 300 MW electric utility boiler. All of these units were fired on high-volatile bituminous coals with sulfur contents ranging from 0.6-3.2 percent. At each site the existing burners were either modified or replaced to provide for low-NO x combustion, and provisions were made to inject calcium based sorbent materials into the furnace space for SO 2 emission control. The results of sorbent injection testing showed moderate levels of SO 2 removal which ranged from approximately 15 to 55 percent at an injected calcium to sulfur molar ratio to 2.0 and with boiler operation at nominal full load. Sulfur capture was found to depend upon the combined effects of parameters such as: sorbent type and reactivity; peak sorbent temperature; coal sulfur content; and the thermal characteristics of the boilers. (8 refs., 58 figs., 6 tabs.)

  13. Sorbents for waste water purification from radionuclides and other toxic substances

    International Nuclear Information System (INIS)

    Maddalone, R.F.; MakKlenason, L.Ts.

    1996-01-01

    The TRW firm (USA) developed the system for sorption and disposal of radionuclides, heavy metals and organic substances, based on utilization of carbon sorbents. The sorbent is produced through processing natural coal by alkali-salt solution and has a large specific pores surface (up to 1000 m 2 /g). The sorbent carboxyl ionogenic groups are able of absorbing heavy metals cations from waste waters. Sorption by uranium constituted 30 mg/l. The sorbent with absorbed substances may be burnt (it contains no sulfur) or delivered for vitrification. The volume of disposed materials constitutes in comparison with existing techniques for uranium isotopes 420000 : 1. The costs are reduced up to 0.26 doll/m 2 of reprocessed water. 2 refs., 2 figs., 4 tabs

  14. Synthesis and characterization of sulfur functionalized graphene oxide nanosheets as efficient sorbent for removal of Pb2+, Cd2+, Ni2+ and Zn2+ ions from aqueous solution: A combined thermodynamic and kinetic studies

    Science.gov (United States)

    Pirveysian, Mahtab; Ghiaci, Mehran

    2018-01-01

    A very simple, one pot method was used for preparation of sulfur functionalized graphene oxide (GO-SOxR) with sodium sulfide and water in reflux condition. The elemental analysis data showed high sulfur content up to 15%. EDS and XPS analysis also proved introduction of sulfur element. To make the sorbent more efficient operationally, the GO-SOxR was coated with a mesoporous shell of TiO2 or SiO2. The prepared sorbents were characterized by SEM, TEM, TGA, XPS, XRD, IR and EDS. GO-SOxR@TiO2 and GO-SOxR@SiO2 composites were tested for removal of Pb(II), Cd(II), Ni(II) and Zn(II) as heavy metal ions from aqueous solution in batch method. Adsorption of the heavy metal ions was studied kinetically, and the adsorption capacities of GO-SOxR, GO-SOxR@TiO2, and GO-SOxR@SiO2 were evaluated using equilibrium adsorption isotherms, and compared to other adsorbents used for removal of these heavy metals. Kinetic studies showed that the experimental data was fitted with pseudo second order model. The adsorption capacity of GO was significantly improved by sulfur functionalization and TiO2 coating.

  15. Process using sorbents for the removal of SOx from flue gas

    International Nuclear Information System (INIS)

    Pinnavaia, T.J.; Amareskera, J.; Polansky, C.A.

    1992-01-01

    This patent describes a process for removing the SO x components from a flue gas stream containing oxygen, sulfur dioxide and sulfur trioxide from the combustion of coal from a coal-fired boiler which comprises combusting the coal in the boiler to provide the flue gas stream and contacting the the gas stream with a heated sorbent composition at 400 degrees to 1000 degrees C wherein the the sorbent before being heated is selected from the group consisting of a layered double hydroxide composition of formula: [M 1-x II M x III (OH) 2 ](A n- ) x/n · yH 2 O wherein M II is a divalent metal cation and M III is a trivalent metal cation selected from the group consisting of Group IIA. IIB and IIIA metals as the cation which form metal oxides and which are capable of reacting with SO 2 to form metal sulfites and SO 3 to form metal sulfates, A is an interlayer anion of charge n- which comprises at least one metal atoms selected from the group consisting of main group metals and transition metals which provide oxidation of sulfur dioxide to sulfur trioxide in an amount sufficient that the layered double hydroxide structure promotes the oxidation of the sulfur dioxide to the sulfur trioxide at the combustion conditions within the coal-fired boiler, wherein y is moles of water

  16. Effect of palladium dispersion on the capture of toxic components from fuel gas by palladium-alumina sorbents

    Energy Technology Data Exchange (ETDEWEB)

    John P. Baltrus; Evan J. Granite; Erik C. Rupp; Dennis C. Stanko; Bret Howard; Henry W. Pennline [US DOE National Energy Technology Laboratory, Pittsburgh, PA (United States)

    2011-05-15

    The dispersion and location of Pd in alumina-supported sorbents prepared by different methods was found to influence the performance of the sorbents in the removal of mercury, arsine, and hydrogen selenide from a simulated fuel gas. When Pd is well dispersed in the pores of the support, contact interaction with the support is maximized, Pd is less susceptible to poisoning by sulfur, and the sorbent has better long-term activity for adsorption of arsine and hydrogen selenide, but poorer adsorption capacity for Hg. As the contact interaction between Pd and the support is lessened the Pd becomes more susceptible to poisoning by sulfur, resulting in higher capacity for Hg, but poorer long-term performance for adsorption of arsenic and selenium. 18 refs., 3 figs., 4 tabs.

  17. Zinc-oxide-based sorbents and processes for preparing and using same

    Science.gov (United States)

    Gangwal, Santosh Kumar; Turk, Brian Scott; Gupta, Raghubir Prasael

    2010-03-23

    Zinc oxide-based sorbents, and processes for preparing and using them are provided. The sorbents are preferably used to remove one or more reduced sulfur species from gas streams. The sorbents comprise an active zinc component, optionally in combination with one or more promoter components and/or one or more substantially inert components. The active zinc component is a two phase material, consisting essentially of a zinc oxide (ZnO) phase and a zinc aluminate (ZnAl.sub.2O.sub.4) phase. Each of the two phases is characterized by a relatively small crystallite size of typically less than about 500 Angstroms. Preferably the sorbents are prepared by converting a precursor mixture, comprising a precipitated zinc oxide precursor and a precipitated aluminum oxide precursor, to the two-phase, active zinc oxide containing component.

  18. Hydrogen sulfide removal from hot coal gas by various mesoporous silica supported Mn2O3 sorbents

    International Nuclear Information System (INIS)

    Zhang, Z.F.; Liu, B.S.; Wang, F.; Wang, W.S.; Xia, C.; Zheng, S.; Amin, R.

    2014-01-01

    Graphical abstract: - Highlights: • Mn 2 O 3 /KIT-1 presented the best desulfurization performance at 600–850 °C. • High sulfur capacity of Mn 2 O 3 /KIT-1 correlated closely with 3-D channel of KIT-1. • Desulfurization character depended strongly on framework structure of sorbents. • High steam content suppressed greatly the occurrence of sulfidation reaction. - Abstract: A series of 50 wt% Mn 2 O 3 sorbents was prepared using various mesoporous silica, MCM-41, HMS, and KIT-1 as support. The influence of textural parameters of mesoporous silica, especially type of channel on the desulfurization performance of Mn 2 O 3 sorbents was investigated at 600–850 °C using hot coal gas containing 0.33 vol.% H 2 S. The fresh and used sorbents were characterized by means of N 2 -adsorption, x-ray diffraction (XRD), high resolution transmission microscopy (HRTEM) and H 2 temperature- programmed reduction (H 2 -TPR) techniques. The results confirmed that the manganese oxide was dispersed highly in regular pore channel of the mesoporous supports due to high surface area. Compared with the Mn 2 O 3 /diatomite, all mesoporous silica supported Mn 2 O 3 sorbents exhibited high breakthrough sulfur capacity and a sharp deactivation rate after the breakthrough point. Compared to Mn 2 O 3 /MCM-41 and Mn 2 O 3 /HMS sorbent, the Mn 2 O 3 /KIT-1 showed better desulfurization performance because of the 3D wormhole-like channel. The high sulfur capacity of the Mn 2 O 3 /KIT-1 sorbent was maintained during the eight consecutive desulfurization-regeneration cycles. The Mn 2 O 3 /KIT-1 still presented high desulfurization activity when hot coal gas contained low steam (<5%)

  19. Process for removing sulfur from sulfur-containing gases: high calcium fly-ash

    Science.gov (United States)

    Rochelle, Gary T.; Chang, John C. S.

    1991-01-01

    The present disclosure relates to improved processes for treating hot sulfur-containing flue gas to remove sulfur therefrom. Processes in accordance with the present invention include preparing an aqueous slurry composed of a calcium alkali source and a source of reactive silica and/or alumina, heating the slurry to above-ambient temperatures for a period of time in order to facilitate the formation of sulfur-absorbing calcium silicates or aluminates, and treating the gas with the heat-treated slurry components. Examples disclosed herein demonstrate the utility of these processes in achieving improved sulfur-absorbing capabilities. Additionally, disclosure is provided which illustrates preferred configurations for employing the present processes both as a dry sorbent injection and for use in conjunction with a spray dryer and/or bagfilter. Retrofit application to existing systems is also addressed.

  20. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Berggren, M.H.; Jha, M.C.

    1989-10-01

    AMAX Research Development Center (AMAX R D) investigated methods for enhancing the reactivity and durability of zinc ferrite desulfurization sorbents. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For this program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such as size, strength, and specific surface area during 10 cycles of sulfidation and oxidation. Two base case sorbents, a spherical pellet and a cylindrical extrude used in related METC-sponsored projects, were used to provide a basis for the aimed enhancement in durability and reactivity. Sorbent performance was judged on the basis of physical properties, single particle kinetic studies based on thermogravimetric (TGA) techniques, and multicycle bench-scale testing of sorbents. A sorbent grading system was utilized to quantify the characteristics of the new sorbents prepared during the program. Significant enhancements in both reactivity and durability were achieved for the spherical pellet shape over the base case formulation. Overall improvements to reactivity and durability were also made to the cylindrical extrude shape. The primary variables which were investigated during the program included iron oxide type, zinc oxide:iron oxide ratio, inorganic binder concentration, organic binder concentration, and induration conditions. The effects of some variables were small or inconclusive. Based on TGA studies and bench-scale tests, induration conditions were found to be very significant.

  1. Performance of Zn-Fe-Mn/MCM-48 sorbents for high temperature H2S removal and analysis of regeneration process

    Science.gov (United States)

    Huang, Z. B.; Liu, B. S.; Wang, F.; Amin, R.

    2015-10-01

    MCM-48 was synthesized using a rapid and facile process at room temperature. A series of 50%Zn-Fe-Mn/MCM-48 sorbents were prepared and their performance of hot coal gas desulfurization was investigated. High breakthrough sulfur capacity (13.2 g-S/100 g sorbent) and utilization (66.1%) of 50%1Zn2Fe2Mn/MCM-48 sorbent at 550 °C was achieved. The characterization results of XRD, BET, TPR and FT-IR revealed that MCM-48 had excellent thermal stability at less than 700 °C, ZnMn2O4 and (Mn, Zn)Fe2O4 were mainly active particles in fresh sorbents which were highly dispersed on support. The MCM-48 mesoporous structure remained intact after eight successive desulfurization/regeneration cycles. The regeneration process of 50%1Zn2Fe2Mn/MCM-48 sorbent was analyzed, it indicated that the breakthrough sulfur capacity decline of sorbent was due to the migration of Zn onto the sorbent surface and Zn accumulated on the surface and vaporized to the exterior from the surface. In the TPO test, the oxidation of Zn was different for 50%Zn/MCM-48 at 700 °C. It revealed that the temperature of regeneration for ZnO sorbent should be higher than 700 °C.

  2. Effects of sulfur on lead partitioning during sludge incineration based on experiments and thermodynamic calculations

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Jing-yong, E-mail: www053991@126.com [School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006 (China); Huang, Shu-jie; Sun, Shui-yu; Ning, Xun-an; He, Rui-zhe [School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006 (China); Li, Xiao-ming [Guangdong Testing Institute of Product Quality Supervision, Guangzhou 510330 (China); Chen, Tao [State Key Laboratory of Organic Geochemistry, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640 (China); Luo, Guang-qian [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan 430074 (China); Xie, Wu-ming; Wang, Yu-jie; Zhuo, Zhong-xu; Fu, Jie-wen [School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006 (China)

    2015-04-15

    Highlights: • A thermodynamic equilibrium calculation was carried out. • Effects of three types of sulfurs on Pb distribution were investigated. • The mechanism for three types of sulfurs acting on Pb partitioning were proposed. • Lead partitioning and species in bottom ash and fly ash were identified. - Abstract: Experiments in a tubular furnace reactor and thermodynamic equilibrium calculations were conducted to investigate the impact of sulfur compounds on the migration of lead (Pb) during sludge incineration. Representative samples of typical sludge with and without the addition of sulfur compounds were combusted at 850 °C, and the partitioning of Pb in the solid phase (bottom ash) and gas phase (fly ash and flue gas) was quantified. The results indicate that three types of sulfur compounds (S, Na{sub 2}S and Na{sub 2}SO{sub 4}) added to the sludge could facilitate the volatilization of Pb in the gas phase (fly ash and flue gas) into metal sulfates displacing its sulfides and some of its oxides. The effect of promoting Pb volatilization by adding Na{sub 2}SO{sub 4} and Na{sub 2}S was superior to that of the addition of S. In bottom ash, different metallic sulfides were found in the forms of lead sulfide, aluminosilicate minerals, and polymetallic-sulfides, which were minimally volatilized. The chemical equilibrium calculations indicated that sulfur stabilizes Pb in the form of PbSO{sub 4}(s) at low temperatures (<1000 K). The equilibrium calculation prediction also suggested that SiO{sub 2}, CaO, TiO{sub 2}, and Al{sub 2}O{sub 3} containing materials function as condensed phase solids in the temperature range of 800–1100 K as sorbents to stabilize Pb. However, in the presence of sulfur or chlorine or the co-existence of sulfur and chlorine, these sorbents were inactive. The effect of sulfur on Pb partitioning in the sludge incineration process mainly depended on the gas phase reaction, the surface reaction, the volatilization of products, and the

  3. Enhanced durability and reactivity for zinc ferrite desulfurization sorbent. Volume 1, Bench-scale testing and analysis

    Energy Technology Data Exchange (ETDEWEB)

    Jha, M.C.; Berggren, M.H.

    1989-05-02

    AMAX Research & Development Center (AMAX R&D) has been investigating methods for enhancing the reactivity and durability of the zinc ferrite desulfurization sorbent. Zinc ferrite sorbents are intended for use in desulfurization of hot coal gas in integrated gasification combined cycle (IGCC) or molten carbonate fuel cell (MCFC) applications. For the present program, the reactivity of the sorbent may be defined as its sulfur sorption capacity at the breakthrough point and at saturation in a bench-scale, fixed-bed reactor. Durability may be defined as the ability of the sorbent to maintain important physical characteristics such As size, strength, and specific surface area during 10 cycles of sulfidation and oxidation.

  4. Laboratory simulated slipstream testing of novel sulfur removal processes for gasification application

    International Nuclear Information System (INIS)

    Schmidt, Roland; Tsang, Albert; Cross, Joe; Summers, Clinton; Kornosky, Bob

    2008-01-01

    The Wabash River Integrated Methanol and Power Production from Clean Coal Technologies (IMPPCCT) project is investigating an Early Entrance Coproduction Plant (EECP) concept to evaluate integrated electrical power generation and methanol production from coal and other carbonaceous feedstocks. Research, development and testing (RD and T) that is currently being conducted under the project is evaluating cost effective process systems for removing contaminants, particularly sulfur species, from the generated gas which contains mainly synthesis gas (syngas), CO 2 and steam at concentrations acceptable for the methanol synthesis catalyst. The RD and T includes laboratory testing followed by bench-scale and field testing at the SG Solutions Gasification Plant located in West Terre Haute, Indiana. Actual synthesis gas produced by the plant was utilized at system pressure and temperature for bench-scale field testing. ConocoPhillips Company (COP) developed a sulfur removal technology based on a novel, regenerable sorbent - S Zorb trademark - to remove sulfur contaminants from gasoline at high temperatures. The sorbent was evaluated for its sulfur removal performance from the generated syngas especially in the presence of other components such as water and CO 2 which often cause sorbent performance to decline over time. This publication also evaluates the performance of a regenerable activated carbon system developed by Nucon International, Inc. in polishing industrial gas stream by removing sulfur species to parts-per-billion (ppb) levels. (author)

  5. Carbon behavior in the cyclic operation of dry desulfurization process for oxy-fuel integrated gasification combined cycle power generation

    International Nuclear Information System (INIS)

    Kobayashi, Makoto; Akiho, Hiroyuki

    2016-01-01

    Highlights: • Power plant with semi-closed gas turbine and O_2–CO_2 coal gasifier was studied. • Dry gas sulfur removal sorbent was improved for durability to carbon deposition. • The improved sorbent showed very low amount of deposited carbon during operation. • The sorbent is regenerable to be used repeatedly in the cyclic operation. • The sorbent exhibited high sulfur-removal performance in the cyclic operation. - Abstract: The dry sulfur-removal process is essential to provide suitable syngas treatment for the oxy-fuel integrated gasification combined cycle power generation plant. It is required that the dry sulfur-removal process to be durable to the carbon deposition due to syngas containing high concentration of carbon monoxide in addition to achieve sufficient performance for sulfur removal. Zinc ferrite sorbent is the most promising candidate for the dry sulfur-removal process. The sorbent was improved to enhance durability to the carbon deposition by modifying preparation. The improved sorbent was prepared from sulfates as the raw materials of zinc ferrite, while the former sorbent was using nitrates as the raw materials. The improved sorbent as well as the former sorbent were evaluated on the performance and carbon deposition tendency in oxy-fuel syngas condition in a fixed bed reactor at elevated pressure and temperature. The results expressed that the improved sorbent has higher desulfurization performance and durability to carbon deposition in the condition expected for cyclic operation of the sulfur-removal process in comparison with the former sorbent. The improved sorbent possessed the superior desulfurization performance as well as the capability for inhibit carbon deposition in the oxy-fuel syngas conditions. The results confirmed the enhanced feasibility of the dry sulfur-removal process by utilizing the improved sorbent.

  6. Removal of sulfur from process streams

    International Nuclear Information System (INIS)

    Brignac, D.G.

    1984-01-01

    A process wherein water is added to a non-reactive gas stream, preferably a hydrogen or hydrogen-containing gas stream, sufficient to raise the water level thereof to from about 0.2 percent to about 50 percent, based on the total volume of the process gas stream, and the said moist gas stream is contacted, at elevated temperature, with a particulate mass of a sulfur-bearing metal alumina spinel characterized by the formula MAl 2 O 4 , wherein M is chromium, iron, cobalt, nickel, copper, cadmium, mercury, or zinc to desorb sulfur thereon. In the sulfur sorption cycle, due to the simultaneous adsorption of water and sulfur, the useful life of the metal alumina spinel for sulfur adsorption can be extended, and the sorbent made more easily regenerable after contact with a sulfur-bearing gas stream, notably sulfur-bearing wet hydrogen or wet hydrogen-rich gas streams

  7. Octahedral molecular sieve sorbents and catalysts

    Science.gov (United States)

    Li, Liyu [Richland, WA; King, David L [Richland, WA

    2010-04-20

    Octahedral molecular sieve sorbents and catalysts are disclosed, including silver hollandite and cryptomelane. These materials can be used, for example, to catalyze the oxidation of CO.sub.x (e.g., CO), NO.sub.x (e.g., NO), hydrocarbons (e.g., C.sub.3H.sub.6) and/or sulfur-containing compounds. The disclosed materials also may be used to catalyze other reactions, such as the reduction of NO.sub.2. In some cases, the disclosed materials are capable of sorbing certain products from the reactions they catalyze. Silver hollandite, in particular, can be used to remove a substantial portion of certain sulfur-containing compounds from a gas or liquid by catalysis and/or sorption. The gas or liquid can be, for example, natural gas or a liquid hydrocarbon.

  8. Retrofit acid gas emission control for municipal waste incineration application of dry sorbent injection

    International Nuclear Information System (INIS)

    Zmuda, J.T.; Smith, P.V.

    1991-01-01

    Dry sorbent injection (DSI) has been successfully demonstrated on coal fired boiler applications as a means of reducing sulfur dioxide emissions. More recently, the dry sorbent injection process was applied to an existing municipal waste incinerator to provide acid gas emission controls. The results obtained from the successful demonstration of the sorbent injection system on an existing municipal incinerator are presented. Removal efficiencies of compounds such as HCl, SO 2 , SO 3 , mercury, and others by the use of sorbent injection are shown. Effects of the DSI system on downstream equipment, such as electrostatic precipitators, fabric filters, ash handling systems, and waste management is included. The impacts of the DSI system on the furnace is also discussed. In this paper a discussion of dry sorbent injection as a means of reducing acid gas and other emissions from existing municipal waste incinerators which may be affected by the regulations is presented. An application case study will outline typical exhaust conditions, expected pollution reductions, capital and operating costs, and type of available sorbents and their costs

  9. Hydrogen sulfide removal from hot coal gas by various mesoporous silica supported Mn{sub 2}O{sub 3} sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Z.F.; Liu, B.S., E-mail: bingsiliu@tju.edu.cn; Wang, F.; Wang, W.S.; Xia, C.; Zheng, S.; Amin, R.

    2014-09-15

    Graphical abstract: - Highlights: • Mn{sub 2}O{sub 3}/KIT-1 presented the best desulfurization performance at 600–850 °C. • High sulfur capacity of Mn{sub 2}O{sub 3}/KIT-1 correlated closely with 3-D channel of KIT-1. • Desulfurization character depended strongly on framework structure of sorbents. • High steam content suppressed greatly the occurrence of sulfidation reaction. - Abstract: A series of 50 wt% Mn{sub 2}O{sub 3} sorbents was prepared using various mesoporous silica, MCM-41, HMS, and KIT-1 as support. The influence of textural parameters of mesoporous silica, especially type of channel on the desulfurization performance of Mn{sub 2}O{sub 3} sorbents was investigated at 600–850 °C using hot coal gas containing 0.33 vol.% H{sub 2}S. The fresh and used sorbents were characterized by means of N{sub 2}-adsorption, x-ray diffraction (XRD), high resolution transmission microscopy (HRTEM) and H{sub 2} temperature- programmed reduction (H{sub 2}-TPR) techniques. The results confirmed that the manganese oxide was dispersed highly in regular pore channel of the mesoporous supports due to high surface area. Compared with the Mn{sub 2}O{sub 3}/diatomite, all mesoporous silica supported Mn{sub 2}O{sub 3} sorbents exhibited high breakthrough sulfur capacity and a sharp deactivation rate after the breakthrough point. Compared to Mn{sub 2}O{sub 3}/MCM-41 and Mn{sub 2}O{sub 3}/HMS sorbent, the Mn{sub 2}O{sub 3}/KIT-1 showed better desulfurization performance because of the 3D wormhole-like channel. The high sulfur capacity of the Mn{sub 2}O{sub 3}/KIT-1 sorbent was maintained during the eight consecutive desulfurization-regeneration cycles. The Mn{sub 2}O{sub 3}/KIT-1 still presented high desulfurization activity when hot coal gas contained low steam (<5%)

  10. Mesoporous binary metal oxide nanocomposites: Synthesis, characterization and decontamination of sulfur mustard

    Energy Technology Data Exchange (ETDEWEB)

    Praveen Kumar, J., E-mail: praveenjella10@gmail.com; Prasad, G.K.; Ramacharyulu, P.V.R.K.; Singh, Beer; Gopi, T.; Krishna, R.

    2016-04-15

    Mesoporous MnO{sub 2}–ZnO, Fe{sub 2}O{sub 3}–ZnO, NiO–ZnO, and CeO{sub 2}–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard. They were synthesized by precipitation pyrolysis method and characterized by means of transmission electron microscopy, scanning electron microscopy coupled with energy dispersive analysis of X rays, X ray diffraction, and nitrogen adsorption techniques. The transmission electron microscopy and nitrogen adsorption data indicated the presence of pores with diameter ranging from 10 to 70 nm in the binary metal oxide nanocomposites and these materials exhibited surface area values in the range of 76–134 m{sup 2}/g. These binary metal oxide nanocomposites demonstrated large decontamination efficiencies against sulfur mustard when compared to their single component metal oxide nanoparticles. The binary metal oxide nanocomposites effectively decontaminated sulfur mustard into relatively non toxic products such as chloro ethyl vinyl sulfide, divinyl sulfide, 1,4-oxathiane, etc. The promising decontamination properties of binary metal oxide nanocomposites against sulfur mustard were attributed to the basic sites, Lewis acid sites, and the presence of these sites was confirmed by CO{sub 2} and NH{sub 3} temperature programmed desorption. - Graphical abstract: Mesoporous MnO{sub 2}–ZnO, Fe{sub 2}O{sub 3}–ZnO, NiO–ZnO, and CeO{sub 2}–ZnO binary metal oxide nanocomposites were studied as sorbent decontaminants against sulfur mustard. - Highlights: • Binary metal oxide nanocomposites were synthesized by co-precipitation method. • They were studied as sorbent decontaminants against sulfur mustard. • They decontaminated sulfur mustard into non toxic products. • MnO{sub 2}–ZnO and CeO{sub 2}–ZnO nanocomposites showed greater decontamination efficiency.

  11. Hot-Gas Desulfurization with Sulfur Recovery

    International Nuclear Information System (INIS)

    Portzer, Jeffrey W.; Damle, Ashok S.; Gangwal, Santosh K.

    1997-01-01

    The objective of this study is to develop a second generation HGD process that regenerates the sulfided sorbent directly to elemental sulfur using SO 2 , with minimal consumption of coal gas. The goal is to have better overall economics than DSRP when integrated with the overall IGCC system

  12. Development of Nano-Sulfide Sorbent for Efficient Removal of Elemental Mercury from Coal Combustion Fuel Gas.

    Science.gov (United States)

    Li, Hailong; Zhu, Lei; Wang, Jun; Li, Liqing; Shih, Kaimin

    2016-09-06

    The surface area of zinc sulfide (ZnS) was successfully enlarged using nanostructure particles synthesized by a liquid-phase precipitation method. The ZnS with the highest surface area (named Nano-ZnS) of 196.1 m(2)·g(-1) was then used to remove gas-phase elemental mercury (Hg(0)) from simulated coal combustion fuel gas at relatively high temperatures (140 to 260 °C). The Nano-ZnS exhibited far greater Hg(0) adsorption capacity than the conventional bulk ZnS sorbent due to the abundance of surface sulfur sites, which have a high binding affinity for Hg(0). Hg(0) was first physically adsorbed on the sorbent surface and then reacted with the adjacent surface sulfur to form the most stable mercury compound, HgS, which was confirmed by X-ray photoelectron spectroscopy analysis and a temperature-programmed desorption test. At the optimal temperature of 180 °C, the equilibrium Hg(0) adsorption capacity of the Nano-ZnS (inlet Hg(0) concentration of 65.0 μg·m(-3)) was greater than 497.84 μg·g(-1). Compared with several commercial activated carbons used exclusively for gas-phase mercury removal, the Nano-ZnS was superior in both Hg(0) adsorption capacity and adsorption rate. With this excellent Hg(0) removal performance, noncarbon Nano-ZnS may prove to be an advantageous alternative to activated carbon for Hg(0) removal in power plants equipped with particulate matter control devices, while also offering a means of reusing fly ash as a valuable resource, for example as a concrete additive.

  13. Water Utility Lime Sludge Reuse – An Environmental Sorbent for Power Utilities

    Science.gov (United States)

    Lime sludge can be used as an environmental sorbent to remove sulfur dioxide (SO2) and acid gases, by the ultra-fine CaCO3 particles, and to sequester mercury and other heavy metals, by the Natural Organic Matter and residual activated carbon. The laboratory experimental set up ...

  14. Steam regenerative removal of hydrogen sulfide from hot syngas by a novel tin oxide and yttrium oxide sorbent

    International Nuclear Information System (INIS)

    Yang, Yi; Shi, Yixiang; Cai, Ningsheng

    2017-01-01

    A novel H 2 S sorbent based on SnO 2 and Y 2 O 3 is developed by a co-precipitation method for steam regenerative removal of H 2 S from hot syngas at moderate temperatures (400–500 °C). SnO 2 -Y 2 O 3 sorbent is stable in a reducing atmosphere (i.e. 500 °C, 50% H 2 ) and achieves a 99.9% H 2 S removal during successive desulfurization and regeneration cycles. The addition of yttrium to SnO 2 decreases the reduction property of SnO 2 and no metallic Sn exists in the reducing atmosphere due to the formation of a pyrochlore-type compound, Y 2 Sn 2 O 7 . The SnO 2 -Y 2 O 3 sorbent has a desulfurization performance deterioration with the increasing calcination temperature. The newly developed SnO 2 -Y 2 O 3 sorbent can be regenerated by steam at 500 °C. In the eight successive desulfurization and regeneration cycles, SnO 2 -Y 2 O 3 sorbent has a cyclic breakthrough sulfur capacity of 9 mg/g without significant sulfur capacity loss. - Highlights: • Reversible warm gas H 2 S clean up. • Suppressing SnO 2 reduction by formation of Sn 2 Y 2 O 7 . • Sn2Y-700 steam regeneration and cycling characterization.

  15. Calcium oxide doped sorbents for CO{sub 2} uptake in the presence of SO{sub 2} at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Lu, H.; Smirniotis, P.G. [University of Cincinnati, Cincinnati, OH (United States)

    2009-06-15

    There is an urgent need to understand sorbent tolerance for capturing carbon dioxide (CO{sub 2}) in the presence of sulfur dioxide (SO{sub 2}). Sulfur oxide is emitted together with CO{sub 2} from various combustion systems and can cause severe air pollution. In this study, the behavior of different dopants on the performance of calcium oxide (CaO) sorbent for capturing CO{sub 2} in the presence of SO{sub 2} was investigated. Three main sets of experiments were carried out to study carbonation and sulfation both separately and simultaneously using a thermogravimetric analyzer (TGA). The results show that SO{sub 2} reduced the capability of the sorbents for capturing CO{sub 2} because of the competition between carbonation and sulfation reactions. Formation of calcium carbonate (CaCO{sub 3}) and calcium sulfate (CaSO{sub 4}) took place upon carbonation and sulfation, respectively. Our TGA and X-ray photoelectron spectroscopy (XPS) results indicate that the carbonation is totally reversible, while this is not the case with the sulfation. The permanent residual weight gained by the sorbents during the course of sulfation is attributed to the irreversible formation of sulfate species, which is confirmed by both the TGA and XPS results. The Ce promoted CaO sorbent exhibits the best performance for CO{sub 2} capture and is the most SO{sub 2} tolerant sorbent. On the other hand, the Mn doped dopant has the strongest affinity for SO{sub 2}.

  16. Use of zeolites for the removal of volatile sulfur compounds from industrial waste gases and from natural gases

    Energy Technology Data Exchange (ETDEWEB)

    Dudzik,; Z,; Bilska, M

    1974-12-01

    The use of zeolites for the removal of sulfur dioxide from industrial waste gases and for the removal of hydrogen sulfide and volatile mercaptans from the natural gas or synthetic gas manufactured from coal is discussed. The effectiveness and cost of zeolite methods are superior to that of other methods. The best sorption properties with respect to sulfur dioxide are observed in faujasites and erionites. The molecular sieve 13X (a sodium form of low-silicon faujasite) is the most effective sorbent of hydrogen sulfide, produced commercially on a large scale. This zeolite is also a very effective catalyst for simultaneous oxygenation of hydrogen sulfide. The reaction with oxygen can begin at temperatures as low as -80/sup 0/C. The effectiveness of zeolite reactors is enhanced by the presence of oxygen in the gas being purified, and is hindered by the presence of water or water vapor. The extraordinary catalytic activity of sodium faujasites is due to free donors, and sulfur and oxygen ion donors at their surface. A zeolite reactor is also economical.

  17. Research improvement in Zn-based sorbent for hot gas desulfurization

    Energy Technology Data Exchange (ETDEWEB)

    X. Bu; Y. Ying; C. Zhang; W. Peng [China Coal Research Institute (CCRI), Beijing (China). Beijing Research Institute of Coal Chemistry

    2005-07-01

    Two Zn-based sorbents, named as L-991 and L-992, used for hot gas desulfurization were developed. The L-992, which was prepared by changing the Zn/Ti ratio and adding a certain proportion of Cu and Mn metal oxide, acquired better performance than L-991. The suitable desulfurisation temperature was 600-700{sup o}C for the L-991 and 600-800{sup o}C for the L-992. The sulfur capacity was about 16 g/100 g and 19-21 g/100 g of L-991 and L-992 respectively. After 17 multi-cycles sulfidation/regeneration tests, the sulfur capacity of the L-991 decreased greatly, while that of the L-992 still remained at 17 g/100 g. Both the sorbents showed orderly crystalline orientation and the particle size did not change. Sulfidation and regeneration tests were done both on lab micro-fixed bed reactor and SMOVEN equipment. During the continuous tests, the H{sub 2}S concentration can be reduced from about 10 g/m{sup 3} to less than 20 mg/m{sup 3}, the H{sub 2}S removal efficiency being {gt} 99%. 14 refs., 9 figs., 2 tabs.

  18. ACTIVATION AND REACTIVITY OF NOVEL CALCIUM-BASED SORBENTS FOR DRY SO2 CONTROL IN BOILERS

    Science.gov (United States)

    Chemically modified calcium hydroxide (Ca(OH)2) sorbents developed in the U.S. Environmental Protection Agency's Air and Energy Engineering Research Laboratory (AEERL) for sulfur dioxide (SO2) control in utility boilers were tested in an electrically heated, bench-scale isotherma...

  19. Molybdenum-based additives to mixed-metal oxides for use in hot gas cleanup sorbents for the catalytic decomposition of ammonia in coal gases

    Science.gov (United States)

    Ayala, Raul E.

    1993-01-01

    This invention relates to additives to mixed-metal oxides that act simultaneously as sorbents and catalysts in cleanup systems for hot coal gases. Such additives of this type, generally, act as a sorbent to remove sulfur from the coal gases while substantially simultaneously, catalytically decomposing appreciable amounts of ammonia from the coal gases.

  20. DB Riley-low emission boiler system (LEBS): Superior power for the 21st century

    Energy Technology Data Exchange (ETDEWEB)

    Beittel, R. [DB Riley, Inc., Worcester, MA (United States); Ruth, L.A. [Dept. of Energy, Pittsburgh, PA (United States)

    1997-12-31

    In conjunction with the US Department of Energy, DB Riley, Inc., is developing a highly advanced coal-fired power-generation plant called the Low Emission Boiler Systems (LEBS). By the year 2000, LEBS will provide the US electric power industry with a reliable, efficient, cost-effective, environmentally superior alternative to current technologies. LEBS incorporates significant advances in coal combustion, supercritical steam boiler design, environmental control, and materials development. The system will include a state-of-the-art steam cycle operating at supercritical steam conditions; a slagging combustor that produces vitrified ash by-products; low nitrogen oxide (NOx) burners; a new, dry, regenerable flue gas cleanup system (copper oxide process) for simultaneously capturing sulfur dioxide (SO{sub 2}) and nitrogen oxides (NOx); a pulse-jet fabric filter for particulate capture; and a low-temperature heat-recovery system. The copper oxide flue gas cleanup system, which has been under development at DOE`s Pittsburgh field center, removes over 98% of SO{sub 2} and 95% of NOx from flue gas. A new moving-bed design provides efficient sorbent utilization that lowers the cleanup process cost. The captured SO{sub 2} can be converted to valuable by-products such as sulfuric acid and/or element sulfur, and the process generates no waste.

  1. Synergistic capture mechanisms for alkali and sulfur species from combustion. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Peterson, T.W.; Shadman, F.; Wendt, J.O.L.; Mwabe, P.O.

    1994-02-01

    Experimental work was carried out on a 17 kW, 600 cm long, gas laboratory combustor, to investigate the post flame reactive capture of alkali species by kaolinite. Emphasis was on alkali/sorbent interactions occurring in flue gas at temperatures above the alkali dewpoint and on the formation of water insoluble reaction products. Time-temperature studies were carried out by injecting kaolinite at different axial points along the combustor. The effect of chlorine and sulfur on alkali capture was investigated by doping the flame with SO{sub 2} and Cl{sub 2} gases to simulate coal flame environments. Particle time and temperature history was kept as close as possible to that which would ordinarily be found in a practical boiler. Experiments designed to extract apparent initial reaction rates were carried using a narrow range, 1-2 {mu}m modal size sorbent, while, a coarse, multi size sorbent was used to investigate the governing transport mechanisms. The capture reaction has been proposed to be between alkali hydroxide and activated kaolinite, and remains so in the presence of sulfur and chlorine. The presence of sulfur reduces sodium capture by under 10% at 1300{degree}C. Larger reductions at lower temperatures are attributed to the elevated dewpoint of sodium ({approximately}850{degree}C) with subsequent reduction in sorbent residence time in the alkali gas phase domain. Chlorine reduces sodium capture by 30% across the temperature range covered by the present experiments. This result has been linked to thermodynamic equilibria between sodium hydroxide, sodium chloride and water.

  2. Durable zinc ferrite sorbent pellets for hot coal gas desulfurization

    Science.gov (United States)

    Jha, Mahesh C.; Blandon, Antonio E.; Hepworth, Malcolm T.

    1988-01-01

    Durable, porous sulfur sorbents useful in removing hydrogen sulfide from hot coal gas are prepared by water pelletizing a mixture of fine zinc oxide and fine iron oxide with inorganic and organic binders and small amounts of activators such as sodium carbonate and molybdenite; the pellets are dried and then indurated at a high temperature, e.g., 1800.degree. C., for a time sufficient to produce crush-resistant pellets.

  3. Superior supercapacitors based on nitrogen and sulfur co-doped hierarchical porous carbon: Excellent rate capability and cycle stability

    Science.gov (United States)

    Zhang, Deyi; Han, Mei; Wang, Bing; Li, Yubing; Lei, Longyan; Wang, Kunjie; Wang, Yi; Zhang, Liang; Feng, Huixia

    2017-08-01

    Vastly improving the charge storage capability of supercapacitors without sacrificing their high power density and cycle performance would bring bright application prospect. Herein, we report a nitrogen and sulfur co-doped hierarchical porous carbon (NSHPC) with very superior capacitance performance fabricated by KOH activation of nitrogen and sulfur co-doped ordered mesoporous carbon (NSOMC). A high electrochemical double-layer (EDL) capacitance of 351 F g-1 was observed for the reported NSHPC electrodes, and the capacitance remains at 288 F g-1 even under a large current density of 20 A g-1. Besides the high specific capacitance and outstanding rate capability, symmetrical supercapacitor cell based on the NSHPC electrodes also exhibits an excellent cycling performance with 95.61% capacitance retention after 5000 times charge/discharge cycles. The large surface area caused by KOH activation (2056 m2 g-1) and high utilized surface area owing to the ideal micro/mesopores ratio (2.88), large micropores diameter (1.38 nm) and short opened micropores structure as well as the enhanced surface wettability induced by N and S heteroatoms doping and improved conductivity induced by KOH activation was found to be responsible for the very superior capacitance performance.

  4. Removal of mercury from coal-combustion flue gas using regenerable sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Turchi, C S; Albiston, J; Broderick, T E; Stewart, R M

    1999-07-01

    The US EPA estimates that coal-fired power plants constitute the largest anthropogenic source of mercury emissions in the US. The Agency has contemplated emission regulations for power plants, but the large gas-flow rates and low mercury concentrations involved have made current treatment options prohibitively expensive. ADA Technologies, Inc. (Englewood, Colorado), in conjunction with the US DOE, is developing regenerable sorbents for the removal and recovery of mercury from flue gas. These sorbents are based on the ability of noble metals to amalgamate mercury at typical flue-gas temperatures and release mercury at higher temperatures. The process allows for recovery of mercury with minimal volumes of secondary wastes and no impact on fly ash quality. In 1997 and 1998, ADA tested a 20-cfm sorbent unit at CONSOL Inc.'s coal-combustion test facility in Library, PA. Results from the 1997 tests indicated that the sorbent can remove elemental and oxidized mercury and can be regenerated without loss of capacity. Design changes were implemented in 1998 to enhance the thermal efficiency of the process and to recover the mercury in a stable form. Testing during autumn, 1998 demonstrated 60% to 90% removal efficiency of mercury from a variety of different coals. However, contradictory removal results were obtained at the end of the test period. Subsequent laboratory analyses indicated that the sorbent had lost over half its capacity for mercury due to a decrease in available sites for mercury sorption. The presence of sulfur compounds on the sorbent suggests that thermal cycling may have condensed acid gases on the sorbent leading to deterioration of the active sorption sites. The regeneration time/temperature profile has been altered to minimize this potential in the upcoming power plant tests.

  5. Aerogel sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Begag, Redouane; Rhine, Wendell E.; Dong, Wenting

    2018-04-03

    The current invention describes methods and compositions of various sorbents based on aerogels of various silanes and their use as sorbent for carbon dioxide. Methods further provide for optimizing the compositions to increase the stability of the sorbents for prolonged use as carbon dioxide capture matrices.

  6. Sorbent suppliers

    International Nuclear Information System (INIS)

    Vedder, M.

    1994-01-01

    Sorbents are used to absorb or contain spilled and leaking chemicals, oils, lubricants and other process fluids. They are commonly used around the base of machinery in industrial applications, and in remediating oil spills on land and water. Sorbents are made from biodegradable, inorganic or synthetic materials. Organic materials include corn cobs, wood pulp, paper fiber and cotton. Inorganic materials include clay, perlite, expanded silicates and expanded mica. Synthetic sorbents are made from petroleum- or plastic-based materials such as polyurethane, polyethylene or polypropylene. Sorbents are available in a variety of forms, including pads, rolls, booms, pillows and loose particulate

  7. Micro-Spherical Sulfur/Graphene Oxide Composite via Spray Drying for High Performance Lithium Sulfur Batteries

    Science.gov (United States)

    Tian, Yuan; Sun, Zhenghao; Zhang, Yongguang; Yin, Fuxing

    2018-01-01

    An efficient, industry-accepted spray drying method was used to synthesize micro-spherical sulfur/graphene oxide (S/GO) composites as cathode materials within lithium sulfur batteries. The as-designed wrapping of the sulfur-nanoparticles, with wrinkled GO composites, was characterized by scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The unique morphological design of this material enabled superior discharge capacity and cycling performance, demonstrating a high initial discharge capacity of 1400 mAh g−1 at 0.1 C. The discharge capacity remained at 828 mAh g−1 after 150 cycles. The superior electrochemical performance indicates that the S/GO composite improves electrical conductivity and alleviates the shuttle effect. This study represents the first time such a facile spray drying method has been adopted for lithium sulfur batteries and used in the fabrication of S/GO composites. PMID:29346303

  8. Efficiency of sugarcane bagasse-based sorbents for oil removal from engine washing wastewater.

    Science.gov (United States)

    Guilharduci, Viviane Vasques da Silva; Martelli, Patrícia Benedini; Gorgulho, Honória de Fátima

    2017-01-01

    This work evaluates the efficiency of sugarcane bagasse-based sorbents in the sorption of oil from engine washing wastewater. The sorbents were obtained from sugarcane bagasse in the natural form (SB-N) and modified with either acetic anhydride (SB-Acet) or 3-aminopropyltriethoxysilane (SB-APTS). The results showed that the sorption capacity of these materials decreased in the following order: SB-APTS > SB-N > SB-Acet. The superior oil sorption capacity observed for SB-APTS was attributed to the polar amino end groups in the silane structure, which acted to increase the hydrophilic character of the fibers. However, all the sorbents obtained in this study were able to clean a real sample of wastewater from engine washing, leading to significant reductions in suspended matter, sediment, anionic surfactants, and turbidity.

  9. Sorbent Scoping Studies

    International Nuclear Information System (INIS)

    Chancellor, Christopher John

    2016-01-01

    The Los Alamos National Laboratory-Carlsbad Operations (LANL-CO) office was tasked by the DOE CBFO, Office of the Manager to perform a review of the acceptable knowledge (AK) to identify the oxidizers and sorbents in transuranic (TRU) waste streams, to conduct scoping studies on the oxidizers and sorbents identified in AK review to inform the Quality Level 1 (QL1) testing, and to conduct a series of QL1 tests to provide the scientific data to support a basis of knowledge document for determining the criteria for (1) accepting waste at the Waste Isolation Pilot Plant (WIPP) without treatment, (2) determining waste that will require treatment, and (3) if treatment is required, how the treatment must be performed. The purpose of this report is to present the results of the AK review of sorbents present in active waste streams, provide a technical analysis of the sorbent list, report the results of the scoping studies for the fastest-burning organic sorbent, and provide the list of organic and inorganic sorbents to be used in the development of a Test Plan for Preparation and Testing of Sorbents Mixed with Oxidizer found in Transuranic Waste (DWT-TP-001). The companion report, DWT-RPT-001, Oxidizer Scoping Studies, has similar information for oxidizers identified during the AK review of TRU waste streams. The results of the oxidizer and sorbent scoping studies will be used to inform the QL1 test plan. The QL1 test results will support the development of a basis of knowledge document that will evaluate oxidizing chemicals and sorbents in TRU waste and provide guidance for treatment.

  10. Sorbent Scoping Studies

    Energy Technology Data Exchange (ETDEWEB)

    Chancellor, Christopher John [Los Alamos National Lab. (LANL), Carlsbad, NM (United States). Difficult Waste Team

    2016-11-14

    The Los Alamos National Laboratory–Carlsbad Operations (LANL-CO) office was tasked by the DOE CBFO, Office of the Manager to perform a review of the acceptable knowledge (AK) to identify the oxidizers and sorbents in transuranic (TRU) waste streams, to conduct scoping studies on the oxidizers and sorbents identified in AK review to inform the Quality Level 1 (QL1) testing, and to conduct a series of QL1 tests to provide the scientific data to support a basis of knowledge document for determining the criteria for (1) accepting waste at the Waste Isolation Pilot Plant (WIPP) without treatment, (2) determining waste that will require treatment, and (3) if treatment is required, how the treatment must be performed. The purpose of this report is to present the results of the AK review of sorbents present in active waste streams, provide a technical analysis of the sorbent list, report the results of the scoping studies for the fastest-burning organic sorbent, and provide the list of organic and inorganic sorbents to be used in the development of a Test Plan for Preparation and Testing of Sorbents Mixed with Oxidizer found in Transuranic Waste (DWT-TP-001). The companion report, DWT-RPT-001, Oxidizer Scoping Studies, has similar information for oxidizers identified during the AK review of TRU waste streams. The results of the oxidizer and sorbent scoping studies will be used to inform the QL1 test plan. The QL1 test results will support the development of a basis of knowledge document that will evaluate oxidizing chemicals and sorbents in TRU waste and provide guidance for treatment.

  11. Evaluation of silk-floss fiber and dog fur as sorbent materials for the petroleum sector

    Energy Technology Data Exchange (ETDEWEB)

    Santos, Lucas P. dos [Universidade Federal do Parana (PGMec/UFPR), Curitiba, PR (Brazil). Programa de Pos-Graduacao em Engenharia Mecanica; Dubiella, Juliana [Universidade Federal do Parana (DEMEC/UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica. Programa Institucional de Bolsas de Iniciacao Cientifica; Perotta, Larissa [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Programa Interdisciplinar em Engenharia de Petroleo e Gas Natural; Satyanarayana, Kestur G. [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica; Flores-Sahagun, Thais Sydenstricker [Universidade Federal do Parana (DEMEC/UFPR), Curitiba, PR (Brazil). Dept. de Engenharia Mecanica

    2009-07-01

    In this study silk-floss and dog fur were tested as sorbent materials for oils and the results were compared with peat, a commercial sorbent. Sorption tests were carried out in dry and aqueous systems, with and without stirring for different periods of time (5-1440 min). Density, hydrophobicity, buoyancy and water uptake by the fibers of the impregnated sorbents have been determined. The use of silk-floss and dog fur was also tested in columns to purify water containing toluene, benzene, motor oil or sunflower oil. Breakthrough curves during 120 min were drawn for each material with the samples (oily water or water containing benzene or toluene) and were analyzed by ultraviolet spectroscopy. It was concluded that the silk-floss is the best sorbent material (65.3 g oil/g sorbent) followed by the dog fur (34.6 g oil/g sorbent) and peat (19.5 g oil/g sorbent), for sorption time of 1 h in dynamic condition. The efficiency of the pollutant removal from water with the use of adsorption columns was high for both materials although the use of dog fur was preferable because of the slight superiority in efficiency compared to silk-floss and also, due to the easier packing of the dog fur in the column. (author)

  12. Dry syngas purification process for coal gas produced in oxy-fuel type integrated gasification combined cycle power generation with carbon dioxide capturing feature.

    Science.gov (United States)

    Kobayashi, Makoto; Akiho, Hiroyuki

    2017-12-01

    Electricity production from coal fuel with minimizing efficiency penalty for the carbon dioxide abatement will bring us sustainable and compatible energy utilization. One of the promising options is oxy-fuel type Integrated Gasification Combined Cycle (oxy-fuel IGCC) power generation that is estimated to achieve thermal efficiency of 44% at lower heating value (LHV) base and provide compressed carbon dioxide (CO 2 ) with concentration of 93 vol%. The proper operation of the plant is established by introducing dry syngas cleaning processes to control halide and sulfur compounds satisfying tolerate contaminants level of gas turbine. To realize the dry process, the bench scale test facility was planned to demonstrate the first-ever halide and sulfur removal with fixed bed reactor using actual syngas from O 2 -CO 2 blown gasifier for the oxy-fuel IGCC power generation. Design parameter for the test facility was required for the candidate sorbents for halide removal and sulfur removal. Breakthrough test was performed on two kinds of halide sorbents at accelerated condition and on honeycomb desulfurization sorbent at varied space velocity condition. The results for the both sorbents for halide and sulfur exhibited sufficient removal within the satisfactory short depth of sorbent bed, as well as superior bed conversion of the impurity removal reaction. These performance evaluation of the candidate sorbents of halide and sulfur removal provided rational and affordable design parameters for the bench scale test facility to demonstrate the dry syngas cleaning process for oxy-fuel IGCC system as the scaled up step of process development. Copyright © 2017 Elsevier Ltd. All rights reserved.

  13. Mercury removal sorbents

    Science.gov (United States)

    Alptekin, Gokhan

    2016-03-29

    Sorbents and methods of using them for removing mercury from flue gases over a wide range of temperatures are disclosed. Sorbent materials of this invention comprise oxy- or hydroxyl-halogen (chlorides and bromides) of manganese, copper and calcium as the active phase for Hg.sup.0 oxidation, and are dispersed on a high surface porous supports. In addition to the powder activated carbons (PACs), this support material can be comprised of commercial ceramic supports such as silica (SiO.sub.2), alumina (Al.sub.2O.sub.3), zeolites and clays. The support material may also comprise of oxides of various metals such as iron, manganese, and calcium. The non-carbon sorbents of the invention can be easily injected into the flue gas and recovered in the Particulate Control Device (PCD) along with the fly ash without altering the properties of the by-product fly ash enabling its use as a cement additive. Sorbent materials of this invention effectively remove both elemental and oxidized forms of mercury from flue gases and can be used at elevated temperatures. The sorbent combines an oxidation catalyst and a sorbent in the same particle to both oxidize the mercury and then immobilize it.

  14. Desulfurization sorbent regeneration

    Science.gov (United States)

    Jalan, V.M.; Frost, D.G.

    1982-07-07

    A spent solid sorbent resulting from the removal of hydrogen sulfide from a fuel gas flow is regenerated with a steam-air mixture. The mixture of steam and air may also include additional nitrogen or carbon dioxide. The gas mixture contacts the spent sorbent containing metal sulfide at a temperature above 500/sup 0/C to regenerate the sulfide to metal oxide or carbonate. Various metal species including the period four transition metals and the lanthanides are suitable sorbents that may be regenerated by this method. In addition, the introduction of carbon dioxide gas permits carbonates such as those of strontium, barium and calcium to be regenerated. The steam permits regeneration of spent sorbent without formation of metal sulfate. Moreover, the regeneration will proceed with low oxygen concentrations and will occur without the increase in temperature to minimize the risk of sintering and densification of the sorbent. This method may be used for high-temperature fuel cells.

  15. Identifying parameter windows for sulfur removal by direct limestone injection in the rich zone of staged heat engine combustors

    International Nuclear Information System (INIS)

    Colaluca, M.A.

    1990-01-01

    Recent experimental evidence suggests the possibility of sulfur cleanup by direct injection at gas temperatures that do not thermodynamically favor the absorption of sulfur by the limestone. The purpose of this paper is to analytically investigate possible mechanistic explanations of this observed sulfur capture with the goal of evaluating the potential for limestone injection sulfur capture in direct coal fired gas turbine and diesel engine (heat engines) combustion applications. The method was to use current available data on the physical properties of limestone, and the rates of the pertinent reactions, and to develop mathematical models of the processes experienced by the sorbent particles. The models were then used to predict extent of capture at the high-pressure, high-temperature, short residence time conditions of interest. The goal was to first investigate capture in a single-pulse reactor (combustion bomb) and then to extrapolate these results to advanced coal-fired heat engine combustion environments. Model predictions were in good agreement with observed sulfur capture in cold wall combustion bomb studies and suggest that efficient sulfur capture (in excess of 80 percent calcium utilization) may b e possible when limestone sorbents are injected into high-temperature combustion products, even when the gas temperatures exceed the thermodynamically favored temperature window by several hundred kelvins. This behavior is possible because particle temperatures are moderated and held at levels that favor sulfur capture due to the strongly endothermic calcination reaction

  16. Space-filling polyhedral sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Haaland, Peter

    2016-06-21

    Solid sorbents, systems, and methods for pumping, storage, and purification of gases are disclosed. They derive from the dynamics of porous and free convection for specific gas/sorbent combinations and use space filling polyhedral microliths with facial aplanarities to produce sorbent arrays with interpenetrating interstitial manifolds of voids.

  17. Design of engineered sorbent barriers

    International Nuclear Information System (INIS)

    Jones, E.O.; Freeman, H.D.

    1988-01-01

    A sorbent barrier uses sorbent material such as activated carbon or natural zeolites to prevent the migration of radionuclides from a low-level waste site to the aquifer. The sorbent barrier retards the movement of radioactive contaminants, thereby providing time for the radionuclides to decay. Sorbent barriers can be a simple, effective, and inexpensive method for reducing the migration of radionuclides to the environment. Designing a sorbent barrier consists of using soil and sorbent material properties and site conditions as input to a model which will determine the necessary sorbent barrier thickness to meet contaminant limits. The paper covers the following areas: techniques for measuring sorption properties of barrier materials and underlying soils, use of a radionuclide transport model to determine the required barrier thickness and performance under a variety of site conditions, and cost estimates for applying the barrier

  18. Sorbent Structural Impacts Due to Humidity on Carbon Dioxide Removal Sorbents for Advanced Exploration Systems

    Science.gov (United States)

    Watson, David; Knox, James C.; West, Phillip; Stanley, Christine M.; Bush, Richard

    2015-01-01

    The Life Support Systems Project (LSSP) under the Advanced Exploration Systems (AES) program builds upon the work performed under the AES Atmosphere Resource Recovery and Environmental Monitoring (ARREM) project focusing on the numerous technology development areas. The CO2 removal and associated air drying development efforts are focused on improving the current state-of-the-art system on the International Space Station (ISS) utilizing fixed beds of sorbent pellets by seeking more robust pelletized sorbents, evaluating structured sorbents, and examining alternate bed configurations to improve system efficiency and reliability. A component of the CO2 removal effort encompasses structural stability testing of existing and emerging sorbents. Testing will be performed on dry sorbents and sorbents that have been conditioned to three humidity levels. This paper describes the sorbent structural stability screening efforts in support of the LSS Project within the AES Program.

  19. Design of engineered sorbent barriers

    International Nuclear Information System (INIS)

    Jones, E.O.; Freeman, H.D.

    1988-08-01

    A sorbent barrier uses sorbent material such as activated carbon or natural zeolites to prevent the migration of radionuclides from a low-level waste site to the aquifer. The sorbent barrier retards the movement of radioactive contaminants, thereby providing time for the radionuclides to decay. Sorbent barriers can be a simple, effective, and inexpensive method for reducing the migration of radionuclides to the environment. Designing a sorbent barrier consists of using soil and sorbent material properties and site conditions as input to a model which will determine the necessary sorbent barrier thickness to meet contaminant limits. The paper will cover the following areas: techniques for measuring sorption properties of barrier materials and underlying soils, use of a radionuclide transport model to determine the required barrier thickness and performance under a variety of site conditions, and cost estimates for applying the barrier. 8 refs., 6 figs., 1 tab

  20. SO{sub 2} retention by reactivated CaO-based sorbent from multiple CO{sub 2} capture cycles

    Energy Technology Data Exchange (ETDEWEB)

    Vasilije Manovic; Edward J. Anthony [CANMET Energy Technology Centre-Ottawa, Ottawa, ON (Canada). Natural Resources Canada

    2007-06-15

    This paper examines the reactivation of spent sorbent, produced from multiple CO{sub 2} capture cycles, for use in SO{sub 2} capture. CaO-based sorbent samples were obtained from Kelly Rock limestone using three particle size ranges, each containing different impurities levels. Using a thermogravimetric analyzer (TGA), the sulfation behavior of partially sulfated and unsulfated samples obtained after multiple calcination-carbonation cycles in a tube furnace (TF), following steam reactivation in a pressurized reactor, is examined. In addition, samples calcined/sintered under different conditions after hydration are also examined. The results show that suitably treated spent sorbent has better sulfation characteristics than that of the original sorbent. Thus for example, after 2 h sulfation, {gt} 80% of the CaO was sulfated. In addition, the sorbent showed significant activity even after 4 h when {gt} 95% CaO was sulfated. The results were confirmed by X-ray diffraction (XRD) analysis, which showed that, by the end of the sulfation process, samples contained CaSO{sub 4} with only traces of unreacted CaO. The superior behavior of spent reactivated sorbent appears to be due to swelling of the sorbent particles during steam hydration. The surface area morphology of sorbent after reactivation was examined by scanning electron microscopy (SEM). Ca(OH){sub 2} crystals were seen, which displayed their regular shape, and their elemental composition was confirmed by energy-dispersive X-ray (EDX) analysis. These results allow the proposal of a new process for the use of CaO-based sorbent in fluidized bed combustion (FBC) systems, which incorporates CO{sub 2} capture, sorbent reactivation, and SO{sub 2} retention. 26 refs., 4 figs., 2 tabs.

  1. A Low Cost, High Capacity Regenerable Sorbent for Pre-combustion CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Alptekin, Gokhan

    2012-09-30

    The overall objective of the proposed research is to develop a low cost, high capacity CO{sub 2} sorbent and demonstrate its technical and economic viability for pre-combustion CO{sub 2} capture. The specific objectives supporting our research plan were to optimize the chemical structure and physical properties of the sorbent, scale-up its production using high throughput manufacturing equipment and bulk raw materials and then evaluate its performance, first in bench-scale experiments and then in slipstream tests using actual coal-derived synthesis gas. One of the objectives of the laboratory-scale evaluations was to demonstrate the life and durability of the sorbent for over 10,000 cycles and to assess the impact of contaminants (such as sulfur) on its performance. In the field tests, our objective was to demonstrate the operation of the sorbent using actual coal-derived synthesis gas streams generated by air-blown and oxygen-blown commercial and pilot-scale coal gasifiers (the CO{sub 2} partial pressure in these gas streams is significantly different, which directly impacts the operating conditions hence the performance of the sorbent). To support the field demonstration work, TDA collaborated with Phillips 66 and Southern Company to carry out two separate field tests using actual coal-derived synthesis gas at the Wabash River IGCC Power Plant in Terre Haute, IN and the National Carbon Capture Center (NCCC) in Wilsonville, AL. In collaboration with the University of California, Irvine (UCI), a detailed engineering and economic analysis for the new CO{sub 2} capture system was also proposed to be carried out using Aspen PlusTM simulation software, and estimate its effect on the plant efficiency.

  2. Sorbents for mercury removal from flue gas

    Energy Technology Data Exchange (ETDEWEB)

    Granite, Evan J.; Hargis, Richard A.; Pennline, Henry W.

    1998-01-01

    A review of the various promoters and sorbents examined for the removal of mercury from flue gas is presented. Commercial sorbent processes are described along with the chemistry of the various sorbent-mercury interactions. Novel sorbents for removing mercury from flue gas are suggested. Since activated carbons are expensive, alternate sorbents and/or improved activated carbons are needed. Because of their lower cost, sorbent development work can focus on base metal oxides and halides. Additionally, the long-term sequestration of the mercury on the sorbent needs to be addressed. Contacting methods between the flue gas and the sorbent also merit investigation.

  3. Evaluation of Solid Sorbents as a Retrofit Technology for CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Sjostrom, Sharon [Ada-Es, Inc., Highlands Ranch, CO (United States)

    2016-06-02

    ADA completed a DOE-sponsored program titled Evaluation of Solid Sorbents as a Retrofit Technology for CO2 Capture under program DE-FE0004343. During this program, sorbents were analyzed for use in a post-combustion CO2 capture process. A supported amine sorbent was selected based upon superior performance to adsorb a greater amount of CO2 than the activated carbon sorbents tested. When the most ideal sorbent at the time was selected, it was characterized and used to create a preliminary techno-economic analysis (TEA). A preliminary 550 MW coal-fired power plant using Illinois #6 bituminous coal was designed with a solid sorbent CO2 capture system using the selected supported amine sorbent to both facilitate the TEA and to create the necessary framework to scale down the design to a 1 MWe equivalent slipstream pilot facility. The preliminary techno-economic analysis showed promising results and potential for improved performance for CO2 capture compared to conventional MEA systems. As a result, a 1 MWe equivalent solid sorbent system was designed, constructed, and then installed at a coal-fired power plant in Alabama. The pilot was designed to capture 90% of the CO2 from the incoming flue gas at 1 MWe net electrical generating equivalent. Testing was not possible at the design conditions due to changes in sorbent handling characteristics at post-regenerator temperatures that were not properly incorporated into the pilot design. Thus, severe pluggage occurred at nominally 60% of the design sorbent circulation rate with heated sorbent, although no handling issues were noted when the system was operated prior to bringing the regenerator to operating temperature. Testing within the constraints of the pilot plant resulted in 90% capture of the incoming CO2 at a flow rate equivalent of 0.2 to 0.25 MWe net electrical generating equivalent. The reduction in equivalent flow rate at 90% capture was

  4. Removal of Zn(II) and Hg(II) from aqueous solution on a carbonaceous sorbent chemically prepared from rice husk

    International Nuclear Information System (INIS)

    El-Shafey, E.I.

    2010-01-01

    A carbonaceous sorbent was prepared from rice husk via sulfuric acid treatment. Sorption of Zn(II) and Hg(II) from aqueous solution was studied varying time, pH, metal concentration, temperature and sorbent status (wet and dry). Zn(II) sorption was found fast reaching equilibrium within ∼2 h while Hg(II) sorption was slow reaching equilibrium within ∼120 h with better performance for the wet sorbent than for the dry. Kinetics data for both metals were found to follow pseudo-second order model. Sorption rate of both metals was enhanced with temperature rise. Activation energy, E a , for Zn(II) sorption, was ∼13.0 kJ/mol indicating a diffusion-controlled process ion exchange process, however, for Hg(II) sorption, E a was ∼54 kJ/mol indicating a chemically controlled process. Sorption of both metals was low at low pH and increased with pH increase. Sorption was much higher for Hg(II) than for Zn(II) with higher uptake for both metals by rising the temperature. Hg(II) was reduced to Hg(I) on the sorbent surface. This was confirmed from the identification of Hg 2 Cl 2 deposits on the sorbent surface by scanning electron microscopy and X-ray diffraction. However, no redox processes were observed in Zn(II) sorption. Sorption mechanism is discussed.

  5. Modeling of a Large-Scale High Temperature Regenerative Sulfur Removal Process

    DEFF Research Database (Denmark)

    Konttinen, Jukka T.; Johnsson, Jan Erik

    1999-01-01

    model that does not account for bed hydrodynamics. The pilot-scale test run results, obtained in the test runs of the sulfur removal process with real coal gasifier gas, have been used for parameter estimation. The validity of the reactor model for commercial-scale design applications is discussed.......Regenerable mixed metal oxide sorbents are prime candidates for the removal of hydrogen sulfide from hot gasifier gas in the simplified integrated gasification combined cycle (IGCC) process. As part of the regenerative sulfur removal process development, reactor models are needed for scale......-up. Steady-state kinetic reactor models are needed for reactor sizing, and dynamic models can be used for process control design and operator training. The regenerative sulfur removal process to be studied in this paper consists of two side-by-side fluidized bed reactors operating at temperatures of 400...

  6. Carbon Dioxide Capture from Flue Gas Using Dry Regenerable Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Thomas Nelson; David Green; Paul Box; Raghubir Gupta; Gennar Henningsen

    2007-06-30

    Regenerable sorbents based on sodium carbonate (Na{sub 2}CO{sub 3}) can be used to separate carbon dioxide (CO{sub 2}) from coal-fired power plant flue gas. Upon thermal regeneration and condensation of water vapor, CO{sub 2} is released in a concentrated form that is suitable for reuse or sequestration. During the research project described in this report, the technical feasibility and economic viability of a thermal-swing CO{sub 2} separation process based on dry, regenerable, carbonate sorbents was confirmed. This process was designated as RTI's Dry Carbonate Process. RTI tested the Dry Carbonate Process through various research phases including thermogravimetric analysis (TGA); bench-scale fixed-bed, bench-scale fluidized-bed, bench-scale co-current downflow reactor testing; pilot-scale entrained-bed testing; and bench-scale demonstration testing with actual coal-fired flue gas. All phases of testing showed the feasibility of the process to capture greater than 90% of the CO{sub 2} present in coal-fired flue gas. Attrition-resistant sorbents were developed, and these sorbents were found to retain their CO{sub 2} removal activity through multiple cycles of adsorption and regeneration. The sodium carbonate-based sorbents developed by RTI react with CO{sub 2} and water vapor at temperatures below 80 C to form sodium bicarbonate (NaHCO3) and/or Wegscheider's salt. This reaction is reversed at temperatures greater than 120 C to release an equimolar mixture of CO{sub 2} and water vapor. After condensation of the water, a pure CO{sub 2} stream can be obtained. TGA testing showed that the Na{sub 2}CO3 sorbents react irreversibly with sulfur dioxide (SO{sub 2}) and hydrogen chloride (HCl) (at the operating conditions for this process). Trace levels of these contaminants are expected to be present in desulfurized flue gas. The sorbents did not collect detectable quantities of mercury (Hg). A process was designed for the Na{sub 2}CO{sub 3}-based sorbent that

  7. Sulfur cathode integrated with multileveled carbon nanoflake-nanosphere networks for high-performance lithium-sulfur batteries

    International Nuclear Information System (INIS)

    Li, S.H.; Wang, X.H.; Xia, X.H.; Wang, Y.D.; Wang, X.L.; Tu, J.P.

    2017-01-01

    Tailored design/construction of high-quality sulfur/carbon composite cathode is critical for development of advanced lithium-sulfur batteries. We report a powerful strategy for integrated fabrication of sulfur impregnated into three-dimensional (3D) multileveled carbon nanoflake-nanosphere networks (CNNNs) by means of sacrificial ZnO template plus glucose carbonization. The multileveled CNNNs are not only utilized as large-area host/backbone for sulfur forming an integrated S/CNNNs composite electrode, but also serve as multiple carbon blocking barriers (nanoflake infrastructure andnanosphere superstructure) to physically confine polysulfides at the cathode. The designedself-supported S/CNNNs composite cathodes exhibit superior electrochemical performances with high capacities (1395 mAh g −1 at 0.1C, and 769 mAh g −1 at 5.0C after 200 cycles) and noticeable cycling performance (81.6% retention after 200 cycles). Our results build a new bridge between sulfur and carbon networks with multiple blocking effects for polysulfides, and provide references for construction of other high-performance sulfur cathodes.

  8. In-situ sulfuration synthesis of sandwiched spherical tin sulfide/sulfur-doped graphene composite with ultra-low sulfur content

    Science.gov (United States)

    Zhao, Bing; Yang, Yaqing; Wang, Zhixuan; Huang, Shoushuang; Wang, Yanyan; Wang, Shanshan; Chen, Zhiwen; Jiang, Yong

    2018-02-01

    SnS is widely studied as anode materials since of its superior structural stability and physicochemical property comparing with other Sn-based composites. Nevertheless, the inconvenience of phase morphology control and excessive consumption of sulfur sources during synthesis hinder the scalable application of SnS nanocomposites. Herein, we report a facile in-situ sulfuration strategy to synthesize sandwiched spherical SnS/sulfur-doped graphene (SnS/S-SG) composite. An ultra-low sulfur content with approximately stoichiometric ratio of Sn:S can effectively promote the sulfuration reaction of SnO2 to SnS and simultaneous sulfur-doping of graphene. The as-prepared SnS/S-SG composite shows a three-dimensional interconnected spherical structure as a whole, in which SnS nanoparticles are sandwiched between the multilayers of graphene sheets forming a hollow sphere. The sandwiched sphere structure and high S doping amount can improve the binding force between SnS and graphene, as well as the structural stability and electrical conductivity of the composite. Thus, a high reversibility of conversion reaction, promising specific capacity (772 mAh g-1 after 100 cycles at 0.1 C) and excellent rate performance (705 and 411 mAh g-1 at 1 C and 10 C, respectively) are exhibited in the SnS/S-SG electrode, which are much higher than that of the SnS/spherical graphene synthesized by traditional post-sulfuration method.

  9. On the potential of absorption and reactive adsorption for desulfurization of ultra low-sulfur commercial diesel in the liquid phase in the presence of fuel additive and bio-diesel

    Energy Technology Data Exchange (ETDEWEB)

    Pieterse, J.A.Z.; Van Eijk, S.; Van Dijk, H.A.J.; Van den Brink, R.W. [Energy research Center of the Netherlands, P.O. Box 1, 1755 ZG Petten (Netherlands)

    2011-03-15

    Sorption of sulfur components in the liquid phase was used to desulfurize ultra low sulfur diesel (ULSD) to below 1 ppmw S. Several concepts of sorption were considered by using both physisorption and chemisorption materials and conditions. Adsorption assisted by reaction with Ni sorbent was found to be most successful. Using a pre-commercial diesel representing a mature diesel on all aspects except for the absence of fuel stabilizers and bio-diesel, a sulfur breakthrough capacity of 2 mg S/g could be achieved using a Ni-sorbent at an acceptable LHSV of 0.7 h{sup -1} on average. However, successive experiments indicated that the desulfurization capacity depended strongly on the presence of fuel-additive and bio-diesel in commercial ULSD. The presence of the cetane improver 2-ethylhexylnitrate (2EHN) was shown to decrease the sulfur capacity by roughly 50%. The presence of bio-diesel (fatty acid methyl ester, abbreviated to FAME) was shown to completely disable the desulfurization process. This was confirmed by comparing BP Ultimate diesel with FAME (obtained in 2008) and without FAME (obtained in 2006). From this evaluation it turned out that the targeted breakthrough capacity of 1 mg S/g sorbent was within reach for commercial ULSD until late 2006 when adding bio-diesel to ULSD became common practice in Europe. Several attempts to remove the additives prior to desulfurization by using copper loaded zeolites, active carbon and silica gel proved unsuccessful to bring the sulfur adsorption capacity for current diesel to the level observed for 2EHN and FAME-free diesel. It is concluded that sorption in the liquid phase does not yet represent a viable desulfurization technology for ultra-low sulfur diesel.

  10. Experimental study on ZnO-TiO_2 sorbents for the removal of elemental mercury

    International Nuclear Information System (INIS)

    Qiu, Kunzan; Zhou, Jinsong; Qi, Pan; Zhou, Qixin; Gao, Xiang; Luo, Zhongyang

    2017-01-01

    ZnO-TiO_2 sorbents synthesized by an impregnation method were characterized through XRD (X-ray diffraction), XPS (X-ray photoelectron spectroscopy) and EDS (Energy dispersive spectrometer) analyses. An experiment concerning the adsorption of Hg0 by ZnO-TiO_2 under a simulated fuel gas atmosphere was then conducted in a benchscale fixed-bed reactor. The effects of ZnO loading amounts and reaction temperatures on Hg"0 removal performance were analyzed. The results showed that ZnO-TiO_2 sorbents exhibited excellent Hg removal capacity in the presence of H2S at 150 .deg. C and 200 .deg. C; 95.2% and 91.2% of Hg0 was removed, respectively, under the experimental conditions. There are two possible causes for the H_2S reacting on the surface of ZnO-TiO_2: (1) H_2S directly reacted with ZnO to form ZnS, (2) H_2S was oxidized to elemental sulfur (S_a_d) by means of active oxygen on the sorbent surface, and then Sad provided active absorption sites for Hg0 to form HgS. This study identifies three reasons why higher temperatures limit mercury removal. First, the reaction between Hg"0 and H_2S is inhibited at high temperatures. Second, HgS, as the resulting product in the reaction of mercury removal, becomes unstable at high temperatures. Third, the desulfurization reaction strengthens at higher temperatures, and it is likely that H_2S directly reacts with ZnO, thus decreasing the Sad on the sorbent surfaces.

  11. Sorbents for the oxidation and removal of mercury

    Science.gov (United States)

    Olson, Edwin S [Grand Forks, ND; Holmes, Michael J [Thompson, ND; Pavlish, John H [East Grand Forks, MN

    2008-10-14

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  12. Sorbents for the oxidation and removal of mercury

    Science.gov (United States)

    Olson, Edwin S [Grand Forks, ND; Holmes, Michael J [Thompson, ND; Pavlish, John H [East Grand Forks, MN

    2012-05-01

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  13. Sorbents for the oxidation and removal of mercur

    Science.gov (United States)

    Olson, Edwin S.; Holmes, Michael J.; Pavlish, John Henry

    2017-09-12

    A promoted activated carbon sorbent is described that is highly effective for the removal of mercury from flue gas streams. The sorbent comprises a new modified carbon form containing reactive forms of halogen and halides. Optional components may be added to increase reactivity and mercury capacity. These may be added directly with the sorbent, or to the flue gas to enhance sorbent performance and/or mercury capture. Mercury removal efficiencies obtained exceed conventional methods. The sorbent can be regenerated and reused. Sorbent treatment and preparation methods are also described. New methods for in-flight preparation, introduction, and control of the active sorbent into the mercury contaminated gas stream are described.

  14. Developing low-cost carbon-based sorbents for Hg capture from flue gas

    Energy Technology Data Exchange (ETDEWEB)

    Perry, R.; Lakatos, J.; Snape, C.E.; Sun, C. [University of Nottingham, Nottingham (United Kingdom). Nottingham Fuel and Energy Centre

    2005-07-01

    To help reduce the cost of Hg capture from flue gas a number of low-cost carbons are being investigated, including activated tyre char and PFA carbon, in conjunction with some of the pre-treatments that have been found to be effective for commercial actived carbons. Experimental conditions for screening the sorbents have been selected to determine breakthrough capacities rapidly. The unactivated carbons have low breakthrough capacities under the test conditions employed (around 0.1 mg g{sup -1}) but these improve upon steam activation (around 0.25 mg g{sup -1}) but are still lower than those of non-impregnated commercial activated carbons (around 0.4-0.7 mg g{sup -1}), due to their lower surface areas. Comparable improvements to the commercial carbons have been achieved for impregnation treatments, including sulfur and bromine. However, certain gasification chars do have much higher breakthrough capacities than commercial carbons used for flue gas injection. Manganese oxide impregnation with low concentration is particularly effective for the activated and unactivated carbons giving breakthrough capacities comparable to the commercial carbons. Pointers for further increasing breakthrough and equilibrium capacities for carbon-based sorbents are discussed. 7 refs., 1 fig., 3 tabs.

  15. Preparation and electrochemical performance of sulfur-alumina cathode material for lithium-sulfur batteries

    International Nuclear Information System (INIS)

    Dong, Kang; Wang, Shengping; Zhang, Hanyu; Wu, Jinping

    2013-01-01

    Highlights: ► Micron-sized alumina was synthesized as adsorbent for lithium-sulfur batteries. ► Sulfur-alumina material was synthesized via crystallizing nucleation. ► The Al 2 O 3 can provide surface area for the deposition of Li 2 S and Li 2 S 2 . ► The discharge capacity of the battery is improved during the first several cycles. - Abstract: Nano-sized sulfur particles exhibiting good adhesion with conducting acetylene black and alumina composite materials were synthesized by means of an evaporated solvent and a concentrated crystallization method for use as the cathodes of lithium-sulfur batteries. The composites were characterized and examined by X-ray diffraction, environmental scanning electron microscopy and electrochemical methods, such as cyclic voltammetry, electrical impedance spectroscopy and charge–discharge tests. Micron-sized flaky alumina was employed as an adsorbent for the cathode material. The initial discharge capacity of the cathode with the added alumina was 1171 mAh g −1 , and the remaining capacity was 585 mAh g −1 after 50 cycles at 0.25 mA cm −2 . Compared with bare sulfur electrodes, the electrodes containing alumina showed an obviously superior cycle performance, confirming that alumina can contribute to reducing the dissolution of polysulfides into electrolytes during the sulfur charge–discharge process

  16. Novel sorbents for environmental remediation

    Science.gov (United States)

    Manariotis, Ioannis D.; Karapanagioti, Hrissi K.; Werner, David

    2014-05-01

    Nowadays, one of the major environmental problems is the pollution of aquatic systems and soil by persistent pollutants. Persistent pollutants have been found widespread in sediments, surface waters, and drinking water supplies. The removal of pollutants can be accomplished prior to their discharge to receiving bodies or by immobilizing them onto soil. Sorption is the most commonly applied process, and activated carbons have been widely used. Rapid progress in nanotechnology and a new focus on biomass-based instead of non-renewable starting materials have produced a wide range of novel engineered sorbents including biosorbents, biochars, carbon-based nanoparticles, bio-nano hybrid materials, and iron-impregnated activated carbons. Sorbent materials have been used in environmental remediation processes and especially in agricultural soil, sediments and contaminated soil, water treatment, and industrial wastewater treatment. Furthermore, sorbents may enhance the synergistic action of other processes, such as volatilization and biodegradation. Novel sorbents have been employed for the removal or immobilization of persistent pollutants such as and include heavy metals (As, Cr, Cu, Pb, Cd, and Hg), halogenated organic compounds, endocrine disrupting chemicals, metalloids and non-metallic elements, and other organic pollutants. The development and evaluation of novel sorbents requires a multidisciplinary approach encompassing environmental, nanotechnology, physical, analytical, and surface chemistry. The necessary evaluations encompass not only the efficiency of these materials to remove pollutants from surface waters and groundwater, industrial wastewater, polluted soils and sediments, etc., but also the potential side-effects of their environmental applications. The aim of this work is to present the results of the use of biochar and impregnated carbon sorbents for the removal of organic pollutants and metals. Furthermore, the new findings from the forthcoming session

  17. Preparation and electrochemical performance of sulfur-alumina cathode material for lithium-sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Dong, Kang [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China); Wang, Shengping, E-mail: spwang@cug.edu.cn [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China); Zhang, Hanyu; Wu, Jinping [Faculty of Material Science and Chemistry, China University of Geosciences, 388 Lumo Road, 430074 Wuhan (China)

    2013-06-01

    Highlights: ► Micron-sized alumina was synthesized as adsorbent for lithium-sulfur batteries. ► Sulfur-alumina material was synthesized via crystallizing nucleation. ► The Al{sub 2}O{sub 3} can provide surface area for the deposition of Li{sub 2}S and Li{sub 2}S{sub 2}. ► The discharge capacity of the battery is improved during the first several cycles. - Abstract: Nano-sized sulfur particles exhibiting good adhesion with conducting acetylene black and alumina composite materials were synthesized by means of an evaporated solvent and a concentrated crystallization method for use as the cathodes of lithium-sulfur batteries. The composites were characterized and examined by X-ray diffraction, environmental scanning electron microscopy and electrochemical methods, such as cyclic voltammetry, electrical impedance spectroscopy and charge–discharge tests. Micron-sized flaky alumina was employed as an adsorbent for the cathode material. The initial discharge capacity of the cathode with the added alumina was 1171 mAh g{sup −1}, and the remaining capacity was 585 mAh g{sup −1} after 50 cycles at 0.25 mA cm{sup −2}. Compared with bare sulfur electrodes, the electrodes containing alumina showed an obviously superior cycle performance, confirming that alumina can contribute to reducing the dissolution of polysulfides into electrolytes during the sulfur charge–discharge process.

  18. Experimental study on ZnO-TiO{sub 2} sorbents for the removal of elemental mercury

    Energy Technology Data Exchange (ETDEWEB)

    Qiu, Kunzan; Zhou, Jinsong; Qi, Pan; Zhou, Qixin; Gao, Xiang; Luo, Zhongyang [Zhejiang University, Hangzhou (China)

    2017-09-15

    ZnO-TiO{sub 2} sorbents synthesized by an impregnation method were characterized through XRD (X-ray diffraction), XPS (X-ray photoelectron spectroscopy) and EDS (Energy dispersive spectrometer) analyses. An experiment concerning the adsorption of Hg0 by ZnO-TiO{sub 2} under a simulated fuel gas atmosphere was then conducted in a benchscale fixed-bed reactor. The effects of ZnO loading amounts and reaction temperatures on Hg{sup 0} removal performance were analyzed. The results showed that ZnO-TiO{sub 2} sorbents exhibited excellent Hg removal capacity in the presence of H2S at 150 .deg. C and 200 .deg. C; 95.2% and 91.2% of Hg0 was removed, respectively, under the experimental conditions. There are two possible causes for the H{sub 2}S reacting on the surface of ZnO-TiO{sub 2}: (1) H{sub 2}S directly reacted with ZnO to form ZnS, (2) H{sub 2}S was oxidized to elemental sulfur (S{sub ad}) by means of active oxygen on the sorbent surface, and then Sad provided active absorption sites for Hg0 to form HgS. This study identifies three reasons why higher temperatures limit mercury removal. First, the reaction between Hg{sup 0} and H{sub 2}S is inhibited at high temperatures. Second, HgS, as the resulting product in the reaction of mercury removal, becomes unstable at high temperatures. Third, the desulfurization reaction strengthens at higher temperatures, and it is likely that H{sub 2}S directly reacts with ZnO, thus decreasing the Sad on the sorbent surfaces.

  19. Sol-gel derived sorbents

    Science.gov (United States)

    Sigman, Michael E.; Dindal, Amy B.

    2003-11-11

    Described is a method for producing copolymerized sol-gel derived sorbent particles for the production of copolymerized sol-gel derived sorbent material. The method for producing copolymerized sol-gel derived sorbent particles comprises adding a basic solution to an aqueous metal alkoxide mixture for a pH.ltoreq.8 to hydrolyze the metal alkoxides. Then, allowing the mixture to react at room temperature for a precalculated period of time for the mixture to undergo an increased in viscosity to obtain a desired pore size and surface area. The copolymerized mixture is then added to an immiscible, nonpolar solvent that has been heated to a sufficient temperature wherein the copolymerized mixture forms a solid upon the addition. The solid is recovered from the mixture, and is ready for use in an active sampling trap or activated for use in a passive sampling trap.

  20. Sorbent-based Oxygen Production for Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Sethi, Vijay [Western Research Inst. (WRI), Laramie, WY (United States)

    2017-01-31

    Project DE-FE0024075 deals with the development of a moderate-temperature sorbent-based oxygen production technology. Sorbent-based oxygen production process utilizes oxygen-storage properties of Perovskites to (1) adsorb oxygen from air in a solid sorbent, and (2) release the adsorbed oxygen into a sweep gas such as CO2 and/or steam for gasification systems or recycled flue gas for oxy-combustion systems. Pure oxygen can be produced by the use of vacuum instead of a sweep gas to affect the pressure swing. By developing more efficient and stable, higher sorption capacity, newer class of materials operating at moderate temperatures this process represents a major advancement in air separation technology. Newly developed perovskite ceramic sorbent materials with order-disorder transition have a higher O2 adsorption capacity, potentially 200 °C lower operating temperatures, and up to two orders of magnitude faster desorption rates than those used in earlier development efforts. The performance advancements afforded by the new materials lead to substantial savings in capital investment and operational costs. Cost of producing oxygen using sorbents could be as much as 26% lower than VPSA and about 13% lower than a large cryogenic air separation unit. Cost advantage against large cryogenic separation is limited because sorbent-based separation numbers up sorbent modules for achieving the larger capacity.

  1. Crosslinked polymeric ionic liquids as solid-phase microextraction sorbent coatings for high performance liquid chromatography.

    Science.gov (United States)

    Yu, Honglian; Merib, Josias; Anderson, Jared L

    2016-03-18

    Neat crosslinked polymeric ionic liquid (PIL) sorbent coatings for solid-phase microextraction (SPME) compatible with high-performance liquid chromatography (HPLC) are reported for the first time. Six structurally different PILs were crosslinked to nitinol supports and applied for the determination of select pharmaceutical drugs, phenolics, and insecticides. Sampling conditions including sample solution pH, extraction time, desorption solvent, desorption time, and desorption solvent volume were optimized using design of experiment (DOE). The developed PIL sorbent coatings were stable when performing extractions under acidic pH and remained intact in various organic desorption solvents (i.e., methanol, acetonitrile, acetone). The PIL-based sorbent coating polymerized from the IL monomer 1-vinyl-3-(10-hydroxydecyl) imidazolium chloride [VC10OHIM][Cl] and IL crosslinker 1,12-di(3-vinylbenzylimidazolium) dodecane dichloride [(VBIM)2C12] 2[Cl] exhibited superior extraction performance compared to the other studied PILs. The extraction efficiency of pharmaceutical drugs and phenolics increased when the film thickness of the PIL-based sorbent coating was increased while many insecticides were largely unaffected. Satisfactory analytical performance was obtained with limits of detection (LODs) ranging from 0.2 to 2 μg L(-1) for the target analytes. The accuracy of the analytical method was examined by studying the relative recovery of analytes in real water samples, including tap water and lake water, with recoveries varying from 50.2% to 115.9% and from 48.8% to 116.6%, respectively. Copyright © 2016 Elsevier B.V. All rights reserved.

  2. LIFAC sorbent injection desulfurization demonstration project. Final report, volume II: Project performance and economics

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-01-01

    This publication discusses the demonstration of the LIFAC sorbent injection technology at Richmond Power and Light`s Whitewater Valley Unit No. 2, performed under the auspices of the U.S. Department of Energy`s (DOE) Clean Coal Technology Program. LIFAC is a sorbent injection technology capable of removing 75 to 85 percent of a power plant`s SO{sub 2} emissions using limestone at calcium to sulfur molar ratios of between 2 and 2.5 to 1. The site of the demonstration is a coal-fired electric utility power plant located in Richmond, Indiana. The project is being conducted by LIFAC North America (LIFAC NA), a joint venture partnership of Tampella Power Corporation and ICF Kaiser Engineers, in cooperation with DOE, RP&L, and Research Institute (EPRI), the State of Indiana, and Black Beauty Coal Company. The purpose of Public Design Report Volume 2: Project Performance and Economics is to consolidate, for public use, the technical efficiency and economy of the LIFAC Process. The report has been prepared pursuant to the Cooperative Agreement No. DE-FC22-90PC90548 between LIFAC NA and the U.S. Department of Energy.

  3. Sorption of methylxanthines by different sorbents

    Science.gov (United States)

    Dmitrienko, S. G.; Andreeva, E. Yu.; Tolmacheva, V. V.; Terent'eva, E. A.

    2013-05-01

    Sorption of caffeine, theophylline, theobromine, diprophylline, and pentoxyphylline on different sorbents (supercross-linked polystyrene, surface-modified copolymer of styrene and divinylbenzene Strata-X, and carbon nanomaterials Taunit and Diasorb-100-C16T) was studied in a static mode in an effort to find new sorbents suitable for sorption isolation and concentration of methylxanthines. The peculiarities of sorption of methylxanthines were explained in relation to the solution acidity, the nature of the sorbates and their concentration, the nature of the solvent, and the structural characteristics of the sorbents.

  4. Sandwich-Type Nitrogen and Sulfur Codoped Graphene-Backboned Porous Carbon Coated Separator for High Performance Lithium-Sulfur Batteries.

    Science.gov (United States)

    Chen, Feng; Ma, Lulu; Ren, Jiangang; Luo, Xinyu; Liu, Bibo; Zhou, Xiangyang

    2018-03-26

    Lithium-sulfur (Li-S) batteries have been identified as the greatest potential next- generation energy-storage systems because of the large theoretical energy density of 2600 Wh kg -1 . However, its practical application on a massive scale is impeded by severe capacity loss resulted from the notorious polysulfides shuttle. Here, we first present a novel technique to synthesize sandwich-type nitrogen and sulfur codoped graphene-backboned porous carbon (NSGPC) to modify the commercial polypropylene separator in Li-S batteries. The as-synthesized NSGPC exhibits a unique micro/mesoporous carbon framework, large specific surface area (2439.0 m² g -1 ), high pore volume (1.78 cm³ g -1 ), good conductivity, and in situ nitrogen (1.86 at %) and sulfur (5.26 at %) co-doping. Benefiting from the particular physical properties and chemical components of NSGPC, the resultant NSGPC-coated separator not only can facilitate rapid Li⁺ ions and electrons transfer, but also can restrict the dissolution of polysulfides to alleviate the shuttle effect by combining the physical absorption and strong chemical adsorption. As a result, Li-S batteries with NSGPC-coated separator exhibit high initial reversible capacity (1208.6 mAh g -1 at 0.2 C), excellent rate capability (596.6 mAh g -1 at 5 C), and superior cycling stability (over 500 cycles at 2 C with 0.074% capacity decay each cycle). Propelling our easy-designed pure sulfur cathode to a extremely increased mass loading of 3.4 mg cm -2 (70 wt. % sulfur), the Li-S batteries with this functional composite separator exhibit a superior high initial capacity of 1171.7 mAh g -1 , which is quite beneficial to commercialized applications.

  5. Sol-gel niobia sorbent with a positively charged octadecyl ligand providing enhanced enrichment of nucleotides and organophosphorus pesticides in capillary microextraction for online HPLC analysis.

    Science.gov (United States)

    Kesani, Sheshanka; Malik, Abdul

    2018-04-01

    A niobia-based sol-gel organic-inorganic hybrid sorbent carrying a positively charged C 18 ligand (Nb 2 O 5 -C 18 (+ve)) was synthesized to achieve enhanced enrichment capability in capillary microextraction of organophosphorus compounds (which include organophosphorus pesticides and nucleotides) before their online analysis by high-performance liquid chromatography. The sorbent was designed to simultaneously provide three different types of molecular level interactions: electrostatic, Lewis acid-base, and van der Waals interactions. To understand relative contributions of various molecular level analyte-sorbent interactions in the extraction process, two other sol-gel niobia sorbents were also created: (a) a purely inorganic sol-gel niobia sorbent (Nb 2 O 5 ) and (b) an organic-inorganic hybrid sol-gel niobia sorbent carrying an electrically neutral-bonded octadecyl ligand (Nb 2 O 5 -C 18 ). The extraction efficiency of the created sol-gel niobia sorbent (Nb 2 O 5 -C 18 (+ve)) was compared with that of analogously designed and synthesized titania-based sol-gel sorbent (TiO 2 -C 18 (+ve)), taking into consideration that titania-based sorbents present state-of-the-art extraction media for organophosphorus compounds. In capillary microextraction with high-performance liquid chromatography analysis, Nb 2 O 5 -C 18 (+ve) had shown 40-50% higher specific extraction values (a measure of extraction efficiency) over that of TiO 2 -C 18 (+ve). Compared to TiO 2 -C 18 (+ve), Nb 2 O 5 -C 18 (+ve) also provided superior analyte desorption efficiency (96 vs. 90%) during the online release of the extracted organophosphorus pesticides from the sorbent coating in the capillary microextraction capillary to the chromatographic column using reversed-phase high-performance liquid chromatography mobile phase. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. A Li+-conductive microporous carbon–sulfur composite for Li-S batteries

    International Nuclear Information System (INIS)

    Zhang, Wenhua; Qiao, Dan; Pan, Jiaxin; Cao, Yuliang; Yang, Hanxi; Ai, Xinping

    2013-01-01

    Highlights: ► A carbon–sulfur composite was prepared by vaporizing sulfur into the nanopores of Li + -conductive carbon microspheres. ► The redox reaction of S 8 molecules embedded in the nanopores of carbon microspheres proceeds through a solid–solid mechanism at the S/C interfaces. ► The carbon–sulfur composite exhibits a stable cycling performance and a superior high coulombic efficiency of 100%. - Abstract: In this paper, we propose a new strategy to develop high performance sulfur electrode by impregnating sulfur into the micropores of a Li + -insertable carbon matrix with the simultaneous use of a carbonate electrolyte, which does not dissolve polysulfides, to restrain the solution of the reaction intermediates of sulfur. To proof this concept, we prepared a Li + -insertable microporous carbon–sulfur composite by vaporizing sulfur into the micropores of the nanofiber-wired carbon microspheres. The experimental results demonstrate that, in the carbonate electrolyte of 1 M LiPF 6 /PC-EC-DEC, such S/C composite electrode exhibits not only stable cycling performance with a reversible capacity of 720 mAh g −1 after 100 cycles, but also superior high coulombic efficiency of ∼100% upon extended cycling (except the first three cycles). The structural and electrochemical analysis indicates that the improved electrochemical behaviors of the S/C composite arise from a new reaction mechanism, in which Li + ions and electrons transport through the carbon matrix into the interior of the cathode and then react with the embedded sulfur in the S/C solid–solid interfaces, avoiding the solution of the intermediates into the bulk electrolyte. More significantly, the structural design and working mechanism of such a sulfur cathode could be extended to a variety of poorly conductive and easily soluble redox-active materials for battery applications.

  7. Engineered sorbent barriers for low-level waste disposal

    International Nuclear Information System (INIS)

    Mitchell, S.J.; Freeman, H.D.; Buelt, J.L.

    1987-01-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Laboratory is developing sorbent materials to prevent the migration of radionuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Screening studies identified promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite of clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent, adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt%), activated charcoal (6 wt%), synthetic zeolite (20 wt%), and soil (73 wt%) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 2 references, 6 figures, 3 tables

  8. Engineered sorbent barriers for low-level waste disposal.

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Mitchell, S.J.; Buelt, J.L.

    1986-12-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Laboratory is investigating sorbent materials to prevent the migration of soluble radio nuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Laboratory studies identifield promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite or clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent and was adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt%), activated charcoal (6 wt%), synthetic zeolite (20 wt%), and local soil (73 wt%) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow-land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 7 refs., 14 figs., 12 tabs.

  9. Engineered sorbent barriers for low-level waste disposal

    International Nuclear Information System (INIS)

    Freeman, H.D.; Mitchell, S.J.; Buelt, J.L.

    1986-12-01

    The Engineered Sorbent Barriers Program at Pacific Northwest Laboratory is investigating sorbent materials to prevent the migration of soluble radio nuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Laboratory studies identifield promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite or clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent and was adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt%), activated charcoal (6 wt%), synthetic zeolite (20 wt%), and local soil (73 wt%) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow-land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 7 refs., 14 figs., 12 tabs

  10. Sequential SO{sub 2}/CO{sub 2} capture enhanced by steam reactivation of a CaO-based sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Vasilije Manovic; Edward J. Anthony [CANMET Energy Technology Centre-Ottawa, Ottawa, ON (Canada). Natural Resources Canada

    2008-07-15

    The steam hydration reactivation characteristics of three limestone samples after multiple CO{sub 2} looping cycles are presented here. The CO{sub 2} cycles were performed in a tube furnace (TF) and the resulting samples were hydrated by steam in a pressure reactor (PR). The reactivation was performed with spent samples after carbonation and calcination stages. The reactivation tests were done with a saturated steam pressure at 200{sup o}C and also at atmospheric pressure and 100 {sup o}C. The characteristics of the reactivation samples were examined using BET and BJH pore characterization (for the original and spent samples, and samples reactivated under different conditions) and also by means of a thermogravimetric analyzer (TGA). The levels of hydration achieved by the reactivated samples were determined as well as the conversions during sulphation and multiple carbonation cycles. It was found that the presence of a CaCO{sub 3} layer strongly hinders sorbent hydration and adversely affects the properties of the reactivated sorbent with regard to its behavior in sulphation and multiple carbonation cycles. Here, hydration of calcined samples under pressure is the most effective method to produce superior sulphur sorbents. However, reactivation of calcined samples under atmospheric conditions also produces sorbents with significantly better properties in comparison to those of the original sorbents. These results show that separate CO{sub 2} capture and SO{sub 2} retention in fluidized bed systems enhanced by steam reactivation is promising even for atmospheric conditions if the material for hydration is taken from the calciner. 49 refs., 5 figs., 3 tabs.

  11. Properties and reactivity of reactivated calcium-based sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Davini, P. [Pisa University, Pisa (Italy). Dept. of Chemical Engineering

    2002-04-01

    Calcium-based sorbents used in the process of high temperature desulfurisation of flue gases are partly regenerable by hydration with steam; the best results are obtained for treatment temperatures of approximately 300{degree}C. The regeneration process, and the consequent increase in the sorbent consumption can be correlated to the surface characteristics (BET surface area, porosity and pore size distribution) of the sorbents themselves. In particular, the presence of suitable pore structure, also having pores large enough to let molecules easily penetrate the inner part of the sorbent particles, is very important. 27 refs., 9 figs., 2 tabs.

  12. Enhancing the use of coals by gas reburning-sorbent injection: Volume 4 -- Gas reburning-sorbent injection at Lakeside Unit 7, City Water, Light and Power, Springfield, Illinois. Final report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1996-03-01

    A demonstration of Gas Reburning-Sorbent Injection (GR-SI) has been completed at a cyclone-fired utility boiler. The Energy and Environmental Research Corporation (EER) has designed, retrofitted and tested a GR-SI system at City Water Light and Power`s 33 MWe Lakeside Station Unit 7. The program goals of 60% NO{sub x} emissions reduction and 50% SO{sub 2} emissions reduction were exceeded over the long-term testing period; the NO{sub x} reduction averaged 63% and the SO{sub 2} reduction averaged 58%. These were achieved with an average gas heat input of 22% and a calcium (sorbent) to sulfur (coal) molar ratio of 1.8. GR-SI resulted in a reduction in thermal efficiency of approximately 1% at full load due to firing natural gas which forms more moisture in flue gas than coal and also results in a slight increase in air heater exit gas temperature. Minor impacts on other areas of unit performance were measured and are detailed in this report. The project at Lakeside was carried out in three phases, in which EER designed the GR-SI system (Phase 1), completed construction and start-up activities (Phase 2), and evaluated its performance with both short parametric tests and a long-term demonstration (Phase 3). This report contains design and technical performance data; the economics data for all sites are presented in Volume 5.

  13. Silica- and germania-based dual-ligand sol-gel organic-inorganic hybrid sorbents combining superhydrophobicity and π-π interaction. The role of inorganic substrate in sol-gel capillary microextraction.

    Science.gov (United States)

    Seyyal, Emre; Malik, Abdul

    2017-04-29

    Principles of sol-gel chemistry were utilized to create silica- and germania-based dual-ligand surface-bonded sol-gel coatings providing enhanced performance in capillary microextraction (CME) through a combination of ligand superhydrophobicity and π-π interaction. These organic-inorganic hybrid coatings were prepared using sol-gel precursors with bonded perfluorododecyl (PF-C 12 ) and phenethyl (PhE) ligands. Here, the ability of the PF-C 12 ligand to provide enhanced hydrophobic interaction was advantageously combined with π-π interaction capability of the PhE moiety to attain the desired sorbent performance in CME. The effect of the inorganic sorbent component on microextraction performance of was explored by comparing microextraction characteristics of silica- and germania-based sol-gel sorbents. The germania-based dual-ligand sol-gel sorbent demonstrated superior CME performance compared to its silica-based counterpart. Thermogravimetric analysis (TGA) of the created silica- and germania-based dual-ligand sol-gel sorbents suggested higher carbon loading on the germania-based sorbent. This might be indicative of more effective condensation of the organic ligand-bearing sol-gel-active chemical species to the germania-based sol-gel network (than to its silica-based counterpart) evolving in the sol solution. The type and concentration of the organic ligands were varied in the sol-gel sorbents to fine-tune extraction selectivity toward different classes of analytes. Specific extraction (SE) values were used for an objective comparison of the prepared sol-gel CME sorbents. The sorbents with higher content of PF-C 12 showed remarkable affinity for aliphatic hydrocarbons. Compared to their single-ligand sol-gel counterparts, the dual-ligand sol-gel coatings demonstrated significantly superior CME performance in the extraction of alkylbenzenes, providing up to ∼65.0% higher SE values. The prepared sol-gel CME coatings provided low ng L -1 limit of detections (LOD

  14. Sandwich-Type Nitrogen and Sulfur Codoped Graphene-Backboned Porous Carbon Coated Separator for High Performance Lithium-Sulfur Batteries

    Science.gov (United States)

    Chen, Feng; Ma, Lulu; Ren, Jiangang; Luo, Xinyu; Liu, Bibo; Zhou, Xiangyang

    2018-01-01

    Lithium-sulfur (Li-S) batteries have been identified as the greatest potential next- generation energy-storage systems because of the large theoretical energy density of 2600 Wh kg−1. However, its practical application on a massive scale is impeded by severe capacity loss resulted from the notorious polysulfides shuttle. Here, we first present a novel technique to synthesize sandwich-type nitrogen and sulfur codoped graphene-backboned porous carbon (NSGPC) to modify the commercial polypropylene separator in Li-S batteries. The as-synthesized NSGPC exhibits a unique micro/mesoporous carbon framework, large specific surface area (2439.0 m2 g−1), high pore volume (1.78 cm3 g−1), good conductivity, and in situ nitrogen (1.86 at %) and sulfur (5.26 at %) co-doping. Benefiting from the particular physical properties and chemical components of NSGPC, the resultant NSGPC-coated separator not only can facilitate rapid Li+ ions and electrons transfer, but also can restrict the dissolution of polysulfides to alleviate the shuttle effect by combining the physical absorption and strong chemical adsorption. As a result, Li-S batteries with NSGPC-coated separator exhibit high initial reversible capacity (1208.6 mAh g−1 at 0.2 C), excellent rate capability (596.6 mAh g−1 at 5 C), and superior cycling stability (over 500 cycles at 2 C with 0.074% capacity decay each cycle). Propelling our easy-designed pure sulfur cathode to a extremely increased mass loading of 3.4 mg cm−2 (70 wt. % sulfur), the Li-S batteries with this functional composite separator exhibit a superior high initial capacity of 1171.7 mAh g−1, which is quite beneficial to commercialized applications. PMID:29587467

  15. Sandwich-Type Nitrogen and Sulfur Codoped Graphene-Backboned Porous Carbon Coated Separator for High Performance Lithium-Sulfur Batteries

    Directory of Open Access Journals (Sweden)

    Feng Chen

    2018-03-01

    Full Text Available Lithium-sulfur (Li-S batteries have been identified as the greatest potential next- generation energy-storage systems because of the large theoretical energy density of 2600 Wh kg−1. However, its practical application on a massive scale is impeded by severe capacity loss resulted from the notorious polysulfides shuttle. Here, we first present a novel technique to synthesize sandwich-type nitrogen and sulfur codoped graphene-backboned porous carbon (NSGPC to modify the commercial polypropylene separator in Li-S batteries. The as-synthesized NSGPC exhibits a unique micro/mesoporous carbon framework, large specific surface area (2439.0 m2 g−1, high pore volume (1.78 cm3 g−1, good conductivity, and in situ nitrogen (1.86 at % and sulfur (5.26 at % co-doping. Benefiting from the particular physical properties and chemical components of NSGPC, the resultant NSGPC-coated separator not only can facilitate rapid Li+ ions and electrons transfer, but also can restrict the dissolution of polysulfides to alleviate the shuttle effect by combining the physical absorption and strong chemical adsorption. As a result, Li-S batteries with NSGPC-coated separator exhibit high initial reversible capacity (1208.6 mAh g−1 at 0.2 C, excellent rate capability (596.6 mAh g−1 at 5 C, and superior cycling stability (over 500 cycles at 2 C with 0.074% capacity decay each cycle. Propelling our easy-designed pure sulfur cathode to a extremely increased mass loading of 3.4 mg cm−2 (70 wt. % sulfur, the Li-S batteries with this functional composite separator exhibit a superior high initial capacity of 1171.7 mAh g−1, which is quite beneficial to commercialized applications.

  16. CO2 Capacity Sorbent Analysis Using Volumetric Measurement Approach

    Science.gov (United States)

    Huang, Roger; Richardson, Tra-My Justine; Belancik, Grace; Jan, Darrell; Knox, Jim

    2017-01-01

    In support of air revitalization system sorbent selection for future space missions, Ames Research Center (ARC) has performed CO2 capacity tests on various solid sorbents to complement structural strength tests conducted at Marshall Space Flight Center (MSFC). The materials of interest are: Grace Davison Grade 544 13X, Honeywell UOP APG III, LiLSX VSA-10, BASF 13X, and Grace Davison Grade 522 5A. CO2 capacity was for all sorbent materials using a Micromeritics ASAP 2020 Physisorption Volumetric Analysis machine to produce 0C, 10C, 25C, 50C, and 75C isotherms. These data are to be used for modeling data and to provide a basis for continued sorbent research. The volumetric analysis method proved to be effective in generating consistent and repeatable data for the 13X sorbents, but the method needs to be refined to tailor to different sorbents.

  17. Porous-Shell Vanadium Nitride Nanobubbles with Ultrahigh Areal Sulfur Loading for High-Capacity and Long-Life Lithium-Sulfur Batteries.

    Science.gov (United States)

    Ma, Lianbo; Yuan, Hao; Zhang, Wenjun; Zhu, Guoyin; Wang, Yanrong; Hu, Yi; Zhao, Peiyang; Chen, Renpeng; Chen, Tao; Liu, Jie; Hu, Zheng; Jin, Zhong

    2017-12-13

    Lithium-sulfur (Li-S) batteries hold great promise for the applications of high energy density storage. However, the performances of Li-S batteries are restricted by the low electrical conductivity of sulfur and shuttle effect of intermediate polysulfides. Moreover, the areal loading weights of sulfur in previous studies are usually low (around 1-3 mg cm -2 ) and thus cannot fulfill the requirement for practical deployment. Herein, we report that porous-shell vanadium nitride nanobubbles (VN-NBs) can serve as an efficient sulfur host in Li-S batteries, exhibiting remarkable electrochemical performances even with ultrahigh areal sulfur loading weights (5.4-6.8 mg cm -2 ). The large inner space of VN-NBs can afford a high sulfur content and accommodate the volume expansion, and the high electrical conductivity of VN-NBs ensures the effective utilization and fast redox kinetics of polysulfides. Moreover, VN-NBs present strong chemical affinity/adsorption with polysulfides and thus can efficiently suppress the shuttle effect via both capillary confinement and chemical binding, and promote the fast conversion of polysulfides. Benefiting from the above merits, the Li-S batteries based on sulfur-filled VN-NBs cathodes with 5.4 mg cm -2 sulfur exhibit impressively high areal/specific capacity (5.81 mAh cm -2 ), superior rate capability (632 mAh g -1 at 5.0 C), and long cycling stability.

  18. NIFSIL - a composite sorbent for caesium - properties and application

    International Nuclear Information System (INIS)

    Rajec, P.; Orechovska, J.

    1998-01-01

    Samples of the potassium-nickel ferrocyanides K 2 NiFe(CN) 6 , KNi 1,5 Fe(CN) 6 and Ni 2 Fe(CN) 6 were prepared and their properties studied with respect to their use as sorbents for caesium. Caesium is fixed on mixed alkaline-nickel ferrocyanide without structural change. The capacity of Cs retention never reached the theoretic value corresponding to a total release of the monovalent ions of the solid. High distribution coefficients (K D in the order of 10 4 cm 3 /g) determined in batch experiments show that these sorbents have a very high affinity for caesium ions, even in the presence of competing K + , Na + and Ca 2+ ions. The sorbents have a good chemical stability in a wide pH-range (2-12). The irradiation of some sorbent samples with high energy gamma-rays ( 60 Co) of a total dose of 1.10 5 Gy caused no remarkable changes in the sorbent properties (K D , sorption capacity and kinetics, mechanical stability). The sorbents were also tested for 85 Sr and 239 Pu and the results carried out under dynamic and batch experiments have shown that sorbents are not suitable for removal of these radionuclides. Potassium nickel hexacyanoferrate incorporated in silica-gel matrix could compete with others sorbents based on insoluble hexacyanoferrates, has the advantage of good radiation stability and suitable granulometry. The sorbent was prepared on a pilot scale with a capacity about 1000 kg per year with the prospect that it could be easily upgraded to an industrial scale

  19. Water purification from radionuclides with using fibroid sorbents

    International Nuclear Information System (INIS)

    Khaydarov, R. A.; Gapurova, O.U.; Khaydarov, R.R.

    2005-01-01

    Full text: Purification waste water and drinking water from radionuclides, heavy metal ions, organic contamination is one of the important problems today. For solving this problem we have created three types of fibroid sorbents on the base of Polyester: cationic and anionic exchange and carbonic. Main properties of these sorbents are described in this article. For example characteristics of the sorbents for removing radionuclides Co-60,57, Zn-65, Sr-89,90, Cs-134,137, etc., radionuclides containing organic molecules M-P-32, M-I-131, M-Mo-99+Tc-99m, M-C-14, etc., heavy metal ions Zn, Ni, Cu, Sb, Pb, Cd, Cr, U, etc., organic molecules (pesticides, phenols, dioxin, benzene, toluene, etc.) were investigated. Influence of pH on percent removal, influence of K, Na and another ions concentrations in the liquid on the percent removal, decreasing of the saturation capacity from number of regeneration and another characteristics are described. Static exchange capacity of the cationic sorbents is 1-2 mg-equ/g and anionic - 0.5-1 mg-equ/g. Capacity of the carbonic sorbents for benzene is 100 mg/g. Time of chemical balance setting is 1-2 s. The sorbents are effective in removing the low concentrations of contamination from the water (lower than 100-200 mg/l) and the air (lower than 100 mg/m 3 ). The use of sorbents in drinking water filters and mini-systems is described. The industrial water purification system consists of coagulating unit, sorbent unit and disinfectant unit. The systems are used in atomic power stations, electroplating plants, matches plants, leather and skin treating plants, car-washing stations, etc

  20. Sorbent selection and design considerations for uranium trapping

    International Nuclear Information System (INIS)

    Schultz, R.M.; Hobbs, W.E.; Norton, J.L.; Stephenson, M.J.

    1981-07-01

    The efficient removal of UF 6 from effluent streams can be accomplished through the selection of the best solid sorbent and the implementation of good design principles. Pressure losses, sorbent capacity, reaction kinetics, sorbent regeneration/uranium recovery requirements and the effects of other system components are the performance factors which are summarized. The commonly used uranium trapping materials highlighted are sodium fluoride, H-151 alumina, XF-100 alumina, and F-1 alumina. Sorbent selection and trap design have to be made on a case-by-case basis but the theoretical modeling studies and the evaluation of the performance factors presented can be used as a guide for other chemical trap applications

  1. Tributyl phosphate removal from reprocessing off-gas streams using a selected sorbent

    International Nuclear Information System (INIS)

    Parker, G.B.

    1980-01-01

    Laboratory experiments used small laboratory-scale columns packed with selected sorbent materials to remove tributyl phosphate (TBP) and iodine at conditions approaching those in actual reprocessing off-gas streams. The sorbent materials for TBP removal were placed upstream of iodine sorbent materials to protect the iodine sorbent from the deleterious effects of TBP. Methyl iodide in an airstream containing 30% TBP in normal paraffin hydrocarbons (NPH) and water vapor was metered to two packed columns of sorbents simultaneously (in parallel). One column contained a segment of 8-in. x 14-in. mesh alumina sorbent for TBP removal, the other did not. The measure of the effectiveness of TBP sorbent materials for TBP removal was determined by comparing the iodine retention of the iodine sorbent materials in the two parallel columns. Results from an 18 wt % Ag substituted mordenite iodine sorbent indicated that the iodine retention capacity of the sorbent was reduced 60% by the TBP and that the column containing iodine sorbent material protected by the alumina TBP sorbent retained 30 times more iodine than the column without TBP sorbent. TBP concentration was up to 500 mg/m 3 . Similar experiments using a 7 wt % Ag impregnated silica gel indicated that the TBP vapor had little effect on the iodine retention of the silica gel material. The stoichiometric maximum amount of iodine was retained by the silica gel material. Further experiments were conducted assessing the effects of NO 2 on iodine retention of this 7 wt % Ag sorbent. After the two columns were loaded with iodine in the presence of TBP (in NPH), one column was subjected to 2 vol % NO 2 in air. From visual comparison of the two columns, it appeared that the NO 2 regenerated the silica gel iodine sorbent and that iodine was washed off the silica gel iodine sorbent leaving the sorbent in the original state

  2. Assessment of spent mushroom substrate as sorbent of fungicides: influence of sorbent and sorbate properties.

    Science.gov (United States)

    Marín-Benito, Jesús M; Rodríguez-Cruz, M Sonia; Andrades, M Soledad; Sánchez-Martín, María J

    2012-01-01

    The capacity of spent mushroom substrate (SMS) as a sorbent of fungicides was evaluated for its possible use in regulating pesticide mobility in the environment. The sorption studies involved four different SMS types in terms of nature and treatment and eight fungicides selected as representative compounds from different chemical groups. Nonlinear sorption isotherms were observed for all SMS-fungicide combinations. The highest sorption was obtained by composted SMS from Agaricus bisporus cultivation. A significant negative and positive correlation was obtained between the K(OC) sorption constants and the polarity index values of sorbents and the K(OW) of fungicides, respectively. The statistic revealed that more than 77% of the variability in the K(OW) could be explained considering these properties jointly. The other properties of both the sorbent (total carbon, dissolved organic carbon, or pH) and the sorbate (water solubility) were nonsignificant. The hysteresis values for cyprodinil (log K(OW)= 4) were for all the sorbents much higher (>3) than for other fungicides. This was consistent with the remaining sorption after desorption considered as an indicator of the sorption efficiency of SMS for fungicides. Changes in the absorption bands of fungicides sorbed by SMS observed by FTIR permitted establishing the interaction mechanism of fungicides with SMS. The findings of this work provide evidence for the potential capacity of SMS as a sorbent of fungicides and the low desorption observed especially for some fungicides, although they suggest that more stabilized or humified organic substrates should be produced to enhance their efficiency in environmental applications. Copyright © by the American Society of Agronomy, Crop Science Society of America, and Soil Science Society of America, Inc.

  3. Engineered sorbent barriers for low-level waste disposal

    International Nuclear Information System (INIS)

    Mitchell, S.J.; Freeman, H.D.; Buelt, J.L.

    1986-01-01

    Pacific Northwest Laboratory is developing sorbent materials to prevent the migration of radionuclides from low-level waste sites. These materials would allow water to pass, preventing the bathtub effect at humid sites. Screening studies identified promising sorbent materials for three key radionuclides: for cesium, greensand; for cobalt, activated charcoal; and for strontium, synthetic zeolite or clinoptilolite. Mixtures of these sorbent materials were tested in 0.6-m-diameter columns using radioactive leachates. To simulate expected worst-case conditions, the leachate solution contained the radionuclides, competing cations, and a chelating agent, adjusted to a pH of 5. A sorbent barrier comprised of greensand (1 wt %), activated charcoal (6 wt %), synthetic zeolite (20 wt %), and soil (73 wt %) achieved the decontamination factors necessary to meet the regulatory performance requirements established for this study. Sorbent barriers can be applied to shallow land burial, as backfill around the waste or engineered structures, or as backup to other liner systems. 2 refs., 6 figs., 3 tabs

  4. Post-combustion carbon capture - solid sorbents and membranes

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, R.M.

    2009-01-15

    This report follows on from that on solvent scrubbing for post-combustion carbon capture from coal-fired power plants by considering the use of solid sorbents and membranes instead of solvents. First, mesoporous and microporous adsorbents are discussed: carbon-based adsorbents, zeolites, hydrotalcites and porous crystals. Attempts have been made to improve the performance of the porous adsorbent by functionalising them with nitrogen groups and specifically, amine groups to react with CO{sub 2} and thus enhance the physical adsorption properties. Dry, regenerable solid sorbents have attracted a good deal of research. Most of the work has been on the carbonation/calcination cycle of natural limestone but there have also been studies of other calcium-based sorbents and alkali metal-based sorbents. Membranes have also been studied as potential post-combustion capture devices. Finally, techno-economic studies predicting the economic performance of solid sorbents and membranes are discussed. 340 refs., 21 figs., 8 tabs.

  5. Influence of lignin on properties of wood-inorganic sorbents

    International Nuclear Information System (INIS)

    Remez, V.P.; Charina, M.V.; Klass, S.M.; Shubin, A.S.; Tkachev, K.V.; Isaeva, O.F.

    1986-01-01

    Present article is devoted to influence of lignin on properties of wood-inorganic sorbents. The influence of component composition of matrix on sorption properties of sorbents and their stability in different mediums is studied. The dependence of sorption capacity of sorbent on component matrix composition and its porous structure is defined.

  6. The antimicrobial efficiency of silver activated sorbents

    International Nuclear Information System (INIS)

    Đolić, Maja B.; Rajaković-Ognjanović, Vladana N.; Štrbac, Svetlana B.; Rakočević, Zlatko Lj.; Veljović, Đorđe N.; Dimitrijević, Suzana I.; Rajaković, Ljubinka V.

    2015-01-01

    Highlights: • Different sorbents were activated by Ag + -ions and modified sorbents were determined by sorption capacities, in range of values: 42.06–3.28 mg/g. • Granulated activated carbon (GAC), natural zeolit (Z) and titanium dioxide (T) activated by Ag + -ions were tested against E. coli, S. aureus and C. albicans. • The most successful bacteria removal was obtained using Ag/Z against S. aureus and E. coli, while the yeast cell reduction reached unsatisfactory effect for all three activated sorbents. • XRD, XPS and FE-SEM analysis showed that the chemical state of the silver activating agent affects the antimicrobial activity, as well as the structural properties of the material. • An overall microbial cell reduction, which is performed by separated antimicrobial tests on the Ag + -activated surface and Ag + -ions in aquatic solutions, is a consequence of both mechanisms. - Abstract: This study is focused on the surface modifications of the materials that are used for antimicrobial water treatment. Sorbents of different origin were activated by Ag + -ions. The selection of the most appropriate materials and the most effective activation agents was done according to the results of the sorption and desorption kinetic studies. Sorption capacities of selected sorbents: granulated activated carbon (GAC), zeolite (Z), and titanium dioxide (T), activated by Ag + -ions were following: 42.06, 13.51 and 17.53 mg/g, respectively. The antimicrobial activity of Ag/Z, Ag/GAC and Ag/T sorbents were tested against Gram-negative bacteria E. coli, Gram-positive bacteria S. aureus and yeast C. albicans. After 15 min of exposure period, the highest cell removal was obtained using Ag/Z against S. aureus and E. coli, 98.8 and 93.5%, respectively. Yeast cell inactivation was unsatisfactory for all three activated sorbents. The antimicrobial pathway of the activated sorbents has been examined by two separate tests – Ag + -ions desorbed from the activated surface to the

  7. Biodiesel as a lubricity additive for ultra low sulfur diesel

    Directory of Open Access Journals (Sweden)

    Subongkoj Topaiboul1 and 2,*

    2010-05-01

    Full Text Available With the worldwide trend to reduce emission from diesel engines, ultra low sulfur diesel has been introduced with thesulfur concentration of less than 10 ppm. Unfortunately, the desulfurization process inevitably reduces the lubricity of dieselfuel significantly. Alternatively, biodiesel, with almost zero sulfur content, has been added to enhance lubricity in an ultralow sulfur diesel. This work has evaluated the effectiveness of the biodiesel amount, sourced from palm and jatropha oil,and origin in ultra low sulfur diesel locally available in the market. Wear scar from a high-frequency reciprocating rig isbenchmarked to the standard value (460 m of diesel fuel lubricity. It was found that very small amount (less than 1% ofbiodiesel from either source significantly improves the lubricity in ultra low sulfur diesel, and the biodiesel from jatropha oilis a superior lubricity enhancer.

  8. Deep Bed Iodine Sorbent Testing FY 2011 Report

    International Nuclear Information System (INIS)

    Soelberg, Nick; Watson, Tony

    2011-01-01

    Nuclear fission results in the production of fission products (FPs) and activation products that increasingly interfere with the fission process as their concentrations increase. Some of these fission and activation products tend to evolve in gaseous species during used nuclear fuel reprocessing. Analyses have shown that I129, due to its radioactivity, high potential mobility in the environment, and high longevity (half life of 15.7 million years), can require control efficiencies of up to 1,000x or higher to meet regulatory emission limits. Deep-bed iodine sorption testing has been done to evaluate the performance of solid sorbents for capturing iodine in off-gas streams from nuclear fuel reprocessing plants. The objectives of the FY 2011 deep bed iodine sorbent testing are: (1) Evaluate sorbents for iodine capture under various conditions of gas compositions and operating temperature (determine sorption efficiencies, capacities, and mass transfer zone depths); and (2) Generate data for dynamic iodine sorption modeling. Three tests performed this fiscal year on silver zeolite light phase (AgZ-LP) sorbent are reported here. Additional tests are still in progress and can be reported in a revision of this report or a future report. Testing was somewhat delayed and limited this year due to initial activities to address some questions of prior testing, and due to a period of maintenance for the on-line GC. Each test consisted of (a) flowing a synthetic blend of gases designed to be similar to an aqueous dissolver off-gas stream over the sorbent contained in three separate bed segments in series, (b) measuring each bed inlet and outlet gas concentrations of iodine and methyl iodide (the two surrogates of iodine gas species considered most representative of iodine species expected in dissolver off-gas), (c) operating for a long enough time to achieve breakthrough of the iodine species from at least one (preferably the first two) bed segments, and (d) post-test purging

  9. Lime-Based Sorbents for High-Temperature CO2 Capture—A Review of Sorbent Modification Methods

    Science.gov (United States)

    Manovic, Vasilije; Anthony, Edward J.

    2010-01-01

    This paper presents a review of the research on CO2 capture by lime-based looping cycles undertaken at CanmetENERGY’s (Ottawa, Canada) research laboratories. This is a new and very promising technology that may help in mitigation of global warming and climate change caused primarily by the use of fossil fuels. The intensity of the anticipated changes urgently requires solutions such as more cost-effective technologies for CO2 capture. This new technology is based on the use of lime-based sorbents in a dual fluidized bed combustion (FBC) reactor which contains a carbonator—a unit for CO2 capture, and a calciner—a unit for CaO regeneration. However, even though natural materials are cheap and abundant and very good candidates as solid CO2 carriers, their performance in a practical system still shows significant limitations. These limitations include rapid loss of activity during the capture cycles, which is a result of sintering, attrition, and consequent elutriation from FBC reactors. Therefore, research on sorbent performance is critical and this paper reviews some of the promising ways to overcome these shortcomings. It is shown that reactivation by steam/water, thermal pre-treatment, and doping simultaneously with sorbent reforming and pelletization are promising potential solutions to reduce the loss of activity of these sorbents over multiple cycles of use. PMID:20948952

  10. Lime-Based Sorbents for High-Temperature CO2 Capture—A Review of Sorbent Modification Methods

    Directory of Open Access Journals (Sweden)

    Edward J. Anthony

    2010-08-01

    Full Text Available This paper presents a review of the research on CO2 capture by lime-based looping cycles undertaken at CanmetENERGY’s (Ottawa, Canada research laboratories. This is a new and very promising technology that may help in mitigation of global warming and climate change caused primarily by the use of fossil fuels. The intensity of the anticipated changes urgently requires solutions such as more cost-effective technologies for CO2 capture. This new technology is based on the use of lime-based sorbents in a dual fluidized bed combustion (FBC reactor which contains a carbonator—a unit for CO2 capture, and a calciner—a unit for CaO regeneration. However, even though natural materials are cheap and abundant and very good candidates as solid CO2 carriers, their performance in a practical system still shows significant limitations. These limitations include rapid loss of activity during the capture cycles, which is a result of sintering, attrition, and consequent elutriation from FBC reactors. Therefore, research on sorbent performance is critical and this paper reviews some of the promising ways to overcome these shortcomings. It is shown that reactivation by steam/water, thermal pre-treatment, and doping simultaneously with sorbent reforming and pelletization are promising potential solutions to reduce the loss of activity of these sorbents over multiple cycles of use.

  11. Post combustion carbon capture - solid sorbents and membranes

    Energy Technology Data Exchange (ETDEWEB)

    Davidson, R.M. [IEA Clean Coal Centre, London (United Kingdom)

    2009-04-15

    This report follows on from that on solvent scrubbing for post-combustion carbon capture from coal-fired power plants by considering the use of solid sorbents and membranes instead of solvents. First, mesoporous and microporous adsorbents are discussed: carbon-based adsorbents, zeolites, hydrotalcites and porous crystals. Attempts have been made to improve the performance of the porous adsorbent by functionalising them with nitrogen groups and specifically, amine groups to react with CO{sub 2} and thus enhance the physical adsorption properties. Dry, regenerable solid sorbents have attracted a good deal of research. Most of the work has been on the carbonation/calcination cycle of natural limestone but there have also been studies of other calcium-based sorbents and alkali metal-based sorbents. Membranes have also been studied as potential post-combustion capture devices. Finally, techno-economic studies predicting the economic performance of solid sorbents and membranes are discussed. The report is available from IEA Clean Coal Centre as report no. CCC/144. See Coal Abstracts entry April 2009 00406. 340 refs., 21 figs., 8 tabs.

  12. Ecologically pure sorbents for power system of Myanmar

    Science.gov (United States)

    Nikitina, I. S.; Moryganova, Y. A.; Maung, Ko Ko; Arefeva, E. A.

    2017-11-01

    Currently, one of the most important problems of the thermal power plant, and many industrial enterprises in different countries is a wastewater treatment for oil products. When choosing the good sorbents is necessary to consider not only the properties and efficiency of the recommended materials, but also the cost, the possibility of environmentally friendly disposal of used sorbents and the possibility of using secondary resources. The purpose of this paper is to study the possibility of using agricultural waste in Myanmar as the sorbents in wastewater treatment containing oil products. The results of experiments have confirmed that rice hulls, and coconut fiber can be effectively used as the sorbents in wastewater treatment containing oil products at concentrations up to 10 mg/l. According to comparative analysis with the conventional sorbent-activated birch carbon (BAC-A) in the Russian power industry has shown that coconut fiber has very good sorption capacity and it is available to use as the raw materials for industries, which does not require to regenerate after using it and can be directly recycled in the factory.

  13. Use of biomass sorbents for oil removal from gas station runoff.

    Science.gov (United States)

    Khan, Eakalak; Virojnagud, Wanpen; Ratpukdi, Thunyalux

    2004-11-01

    The use of biomass sorbents, which are less expensive and more biodegradable than synthetic sorbents, for oil removal from gas station runoff was investigated. A bench-scale flume experiment was conducted to evaluate the oil removal and retention capabilities of the biomass sorbents which included kapok fiber, cattail fiber, Salvinia sp., wood chip, rice husk, coconut husk, and bagasse. Polyester fiber, a commercial synthetic sorbent, was also experimented for comparison purpose. Oil sorption and desorption tests were performed at a water flow rate of 20 lmin-1. In the oil sorption tests, a 50 mgl(-1) of used engine oil-water mixture was synthesized to simulate the gas station runoff. The mass of oil sorbed for all sorbents, except coconut husk and bagasse, was greater than 70%. Cattail fiber and polyester fiber were the sorbents that provided the least average effluent oil concentrations. Oil selectivity (hydrophobic properties) and physical characteristics of the sorbents are the two main factors that influence the oil sorption capability. The used sorbents from the sorption tests were employed in the desorption tests. Results indicated that oil leached out of all the sorbents tested. Polyester fiber released the highest amount of oil, approximately 4% (mass basis) of the oil sorbed. copyright 2004 Elsevier Ltd.

  14. Detoxication and recycling of radioactive waters using selective mineral sorbents

    International Nuclear Information System (INIS)

    Berak, L.

    1980-01-01

    Activated BaSO 4 (designated AB 70) was proposed for use in decontaminating concentrated calcium salt solutions containing a small amount of 226 Ra. The AB 70 concentration factor amounts to 2x1a 3 . A sorption contactor for applying the powder sorbent was proposed and will be tested. The AB 70 sorbent liberates small amounts of sulphates into the decontaminated solution, and thus another suitable mineral sorbent was sought. A new sorbent could be synthetized and tested, called RAS-1 whose Ra/Ca selectivity is comparable to that of AB 70 while its Ra/Ba selectivity is considerably higher. The RAS-1 sorbent is also suitable for radiochemical separation in the analysis and concentration of Ra. (Ha)

  15. The corrosion protection of several aluminum alloys by chromic acid and sulfuric acid anodizing

    Science.gov (United States)

    Danford, M. D.

    1994-01-01

    The corrosion protection afforded 7075-T6, 7075-T3, 6061-T6, and 2024-T3 aluminum alloys by chromic acid and sulfuric acid anodizing was examined using electrochemical techniques. From these studies, it is concluded that sulfuric acid anodizing provides superior corrosion protection compared to chromic acid anodizing.

  16. Oil sorbents from plastic wastes and polymers: A review.

    Science.gov (United States)

    Saleem, Junaid; Adil Riaz, Muhammad; Gordon, McKay

    2018-01-05

    A large volume of the waste produced across the world is composed of polymers from plastic wastes such as polyethylene (HDPE or LDPE), polypropylene (PP), and polyethylene terephthalate (PET) amongst others. For years, environmentalists have been looking for various ways to overcome the problems of such large quantities of plastic wastes being disposed of into landfill sites. On the other hand, the usage of synthetic polymers as oil sorbents in particular, polyolefins, including polypropylene (PP) and polyethylene (PE) have been reported. In recent years, the idea of using plastic wastes as the feed for the production of oil sorbents has gained momentum. However, the studies undertaking such feasibility are rather scattered. This review paper is the first of its kind reporting, compiling and reviewing these various processes. The production of an oil sorbent from plastic wastes is being seen to be satisfactorily achievable through a variety of methods Nevertheless, much work needs to be done regarding further investigation of the numerous parameters influencing production yields and sorbent qualities. For example, differences in results are seen due to varying operating conditions, experimental setups, and virgin or waste plastics being used as feeds. The field of producing oil sorbents from plastic wastes is still very open for further research, and seems to be a promising route for both waste reduction, and the synthesis of value-added products such as oil sorbents. In this review, the research related to the production of various oil sorbents based on plastics (plastic waste and virgin polymer) has been discussed. Further oil sorbent efficiency in terms of oil sorption capacity has been described. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Study of CO2 cyclic absorption stability of CaO-based sorbents derived from lime mud purified by sucrose method.

    Science.gov (United States)

    Ma, AiHua; Jia, QingMing; Su, HongYing; Zhi, YunFei; Tian, Na; Wu, Jing; Shan, ShaoYun

    2016-02-01

    Using lime mud (LM) purified by sucrose method, derived from paper-making industry, as calcium precursor, and using mineral rejects-bauxite-tailings (BTs) from aluminum production as dopant, the CaO-based sorbents for high-temperature CO2 capture were prepared. Effects of BTs content, precalcining time, and temperature on CO2 cyclic absorption stability were illustrated. The cyclic carbonation behavior was investigated in a thermogravimetric analyzer (TGA). Phase composition and morphologies were analyzed by XRD and SEM. The results reflected that the as-synthesized CaO-based sorbent doped with 10 wt% BTs showed a superior CO2 cyclic absorption-desorption conversion during multiple cycles, with conversion being >38 % after 50 cycles. Occurrence of Ca12Al14O33 phase during precalcination was probably responsible for the excellent CO2 cyclic stability.

  18. Simple test guidelines for screening oilspill sorbents for toxicity

    International Nuclear Information System (INIS)

    Blenkinsopp, S.A.; Sergy, G.; Doe, K.; Jackman, P.; Huybers, A.

    1998-01-01

    Environment Canada's Emergencies Science Division has established a program to develop a standard test method suitable for evaluating the toxicity of common sorbent materials. Sorbents are used to absorb or adsorb spilled oil and other hazardous materials. They vary widely in composition and packaging. They are often treated with oleophilic and hydrophobic compounds to improve performance and have been used in large quantities during oil spills. Until now, their potential toxicity has never been considered. Three tests have been evaluated to determine how appropriate they are in screening the toxicity of sorbents. Seven toxicity test recommendations for sorbents were presented. 7 refs., 3 tabs., 2 figs

  19. Potential of Cogon Grass as an Oil Sorbent

    OpenAIRE

    Wiloso, Edi Iswanto; Barlianti, Vera; Anggraini, Irni Fitria; Hendarsyah, Hendris

    2012-01-01

    Experiments on the potential of Cogon grass (lmperata cylindrica), a weed harmful to other plants, for use as a low-cost and biodegradable oil sorbent were carried out under various spill conditions. Flowers of Cogon grass adsorbed much larger amount of high-viscosity lubricating oil (57.9 g-oil/g-sorbent) than that adsorbed by Peat Sorb (7.7 g-oil/g-sorbent), a commercial oilsorbent based on peat. However, the flowers adsorbed only 27.9 g of low-viscosity crude oillgsorbent. In an oil-water ...

  20. Sorption of Aromatic Compounds with Copolymer Sorbent Materials Containing β-Cyclodextrin.

    Science.gov (United States)

    Wilson, Lee D; Mohamed, Mohamed H; Berhaut, Christopher L

    2011-08-29

    Urethane copolymer sorbent materials that incorporate β-cyclodextrin (CD) have been prepared and their sorption properties with chlorinated aromatic compounds (i.e., pentachlorophenol, 2,4-dichlorophenol and 2,4-dichlorophenoxy acetic acid) have been evaluated. The sorption properties of granular activated carbon (GAC) were similarly compared in aqueous solution at variable pH conditions. The sorbents displayed variable BET surface areas as follows: MDI-X copolymers (granular activated carbon (GAC ~10³ m²/g). The sorption capacities for the copolymers sorbents are listed in descending order, as follows: GAC > CDI-3 copolymer ≈ MDI-3 copolymer. The sorption capacity for the aromatic adsorbates with each sorbent are listed in descending order, as follows: 2,4-dichlorophenol > 2,4-dichlorophenoxy acetic acid > pentachlorophenol. In general, the differences in the sorption properties of the copolymer sorbents with the chlorinated organics were related to the following factors: (i) surface area of the sorbent; (ii) CD content and accessibility; and (iii) and the chemical nature of the sorbent material.

  1. Synthesis and characterization of porous metal oxides and desulfurization studies of sulfur containing compounds

    Science.gov (United States)

    Garces Trujillo, Hector Fabian

    This thesis contains two parts: 1) synthesis and characterization of porous metal oxides that include zinc oxide and a porous mixed-valent manganese oxide with an amorphous structure (AMO) 2) the desulfurization studies for the removal of sulfur compounds. Zinc oxide with different nano-scale morphologies may result in various porosities with different adsorption capabilities. A tunable shape microwave synthesis of ZnO nano-spheres in a co-solvent mixture is presented. The ZnO nano-sphere material is investigated as a desulfurizing sorbent in a fixed bed reactor in the temperature range 200 to 400 °C and compared with ZnO nanorods and platelet-like morphologies. Fresh and sulfided materials were characterized by X-ray diffraction (XRD), BET specific surface area, pore volume, scanning electron microscopy (SEM), X-ray energy dispersive spectroscopy (SEM/EDX), Raman spectroscopy, and thermogravimetric analysis (TGA). The tunable shape microwave synthesis of ZnO presents a high sulfur sorption capacity at temperatures as low as 200 °C which accounts for a three and four fold enhancement over the other preparations presented in this work, and reached 76 % of the theoretical sulfur capacity (TSC) at 300 °C. Another ZnO material with a bimodal micro- and mesopore size distribution investigated as a desulfurizing sorbent presents a sorption capacity that reaches 87% of the theoretical value for desulfurization at 400 °C at breakthrough time. A deactivation model that considers the activity of the solid reactant was used to fit the experimental data. Good agreement between the experimental breakthrough curves and the model predictions are obtained. Manganese oxides are a type of metal oxide materials commonly used in catalytic applications. Little is known about the adsorption capabilities for the removal of sulfur compounds. One of these manganese oxides; amorphous manganese oxide (AMO) is highly promising material for low temperature sorption processes. Amorphous

  2. Different sorbents in calcium looping cycle for CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Cong; Zheng, Ying; Ding, Ning [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

    2013-07-01

    Cyclic CO{sub 2} capture using commercial pure micro CaCO{sub 3} and nano CaCO{sub 3} is investigated in this paper which focuses on the different characteristics two different sorbents during high temperature reactions. The results indicate that the nano CaCO{sub 3} sorbent has higher carbonation conversions and carbonation rates than the micro CaCO{sub 3} sorbent in the cyclic reactions. Furthermore, nano sorbent can retain its fast carbonation rates at the beginning dozens of seconds during each cycle. In contrast, the carbonation rates of micro sorbent diminish with the increase of cycle number. But, unfortunately, CaO derived from nano CaCO3 sorbent sinter much easily. Its grains, which are composed of numerous spherical nanocrystallites, experience dramatic morphological changes during high temperature reactions.

  3. Carbon-Containing Waste of Coal Enterprises in Magnetic Sorbents Technology

    Science.gov (United States)

    Kvashevaya, Ekaterina; Ushakova, Elena; Ushakov, Andrey

    2017-11-01

    The article shows the issues state of coal-mining enterprises carbonaceous wastes utilization, including by obtaining oil-sorbent. The characteristics of the feedstock are presented; experiment methods of obtaining a binder based on the livestock enterprises waste, of forming binder with filler (sawdust, coal waste); of pyrogenetic processing to obtain a sorbent are described. Possible options for the introduction of magnetite (a magnetic component) in the composition of the oil sorbent are considered: on the surface, in the volume of the granule and the magnetite core. In the course of the work it was found that the optimum content of coal dust in the sorbent granules is 75% by weight, and the most effective way of obtaining the magnetic sorbent is to apply the carbon material directly to the "core" of magnetite. However, in this case, the problem of finding an effective binder for magnetite arises. The option of applying magnetite on the surface of a carbon sorbent is not effective. Thus, at present, we use a mixture of coal waste, which binds to the uniform distribution of magnetite in the volume. The developed magnetic sorbents can be used in various weather conditions, including strong winds and icing of water bodies, as well as for small and medium currents.

  4. Study and modeling of the reduction of sulfur dioxide, nitrogen oxides and hydrogen chloride by dry injection technologies

    Energy Technology Data Exchange (ETDEWEB)

    Wang Wuyin

    1997-05-01

    The potential and mechanism to reduce acid gases, such as sulfur dioxide (SO{sub 2}), nitrogen oxides (NO{sub x}) and hydrogen chloride (HCl), by dry Ca-based sorbents have been studied to improve the efficiency of the process and sorbent utilization. Several natural limestones were tested for SO{sub 2} removal. Calcium conversion as high as 45 % was achieved in the first 0.3 s at 1000 deg C, 1000 ppm SO{sub 2} and Ca/S=1. A SO{sub 2} removal efficiency of 95 % was reached at Ca/S=2. Two models for estimating the sulfation of CaO at high temperature are presented. Short-residence-time sulfation is described by a pore size distribution model and long-residence-time sulfation by a particle expansion model. The pore size distribution model explains the effects of particle size, pore size distribution and partial pressure of SO{sub 2}, suggesting these three factors be the most important for CaO conversion. For particles larger than 1-2 {mu}m in furnace sorbent injection, pore diameters of 50-300 Aa are desirable. When large particles or long residence times are used, as in fluidized bed combustion, the particle expansion model shows the particle size and the sorbent type to be the main factors affecting the reaction. By using the selected limestone and additives the simultaneous SO{sub 2}/NO{sub x} removal was also measured. Several ammonium salts as well as urea were tested. Urea was found to give the highest NO{sub x} removal efficiency. To fully utilize the unreacted Ca-based sorbents, the spent sorbents from SO{sub 2} reduction processes were tested in a fixed-bed reactor to measure the capacity for HCl removal at 150-600 deg C. The results showed that all spent materials could react with HCl to some extent. After being calcined and slaked, they even showed the same reactivity as pure Ca(OH){sub 2}. A shrinking core model was derived for fixed-bed reactor. For the best sorbent tested, the multiple sorbent utilization reached about 80 %. 100 refs, 42 figs, 12 tabs

  5. Sorption of Aromatic Compounds with Copolymer Sorbent Materials Containing β-Cyclodextrin

    Directory of Open Access Journals (Sweden)

    Lee D. Wilson

    2011-08-01

    Full Text Available Urethane copolymer sorbent materials that incorporate β-cyclodextrin (CD have been prepared and their sorption properties with chlorinated aromatic compounds (i.e., pentachlorophenol, 2,4-dichlorophenol and 2,4-dichlorophenoxy acetic acid have been evaluated. The sorption properties of granular activated carbon (GAC were similarly compared in aqueous solution at variable pH conditions. The sorbents displayed variable BET surface areas as follows: MDI-X copolymers (< 101 m2/g, CDI-X copolymers (< 101 m2/g, and granular activated carbon (GAC ~103 m2/g. The sorption capacities for the copolymers sorbents are listed in descending order, as follows: GAC > CDI-3 copolymer ≈ MDI-3 copolymer. The sorption capacity for the aromatic adsorbates with each sorbent are listed in descending order, as follows: 2,4-dichlorophenol > 2,4-dichlorophenoxy acetic acid > pentachlorophenol. In general, the differences in the sorption properties of the copolymer sorbents with the chlorinated organics were related to the following factors: (i surface area of the sorbent; (ii CD content and accessibility; and (iii and the chemical nature of the sorbent material.

  6. Stabilized sulfur as cathodes for room temperature sodium-ion batteries.

    Energy Technology Data Exchange (ETDEWEB)

    Xu, Yunhua [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Liu, Yang [Sandia National Laboratories (SNL-NM), Albuquerque, NM (United States). Center for Integrated Nanotechnologies; Zhu, Yujie [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Zheng, Shiyou [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Liu, Yihang [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Luo, Chao [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering; Gaskell, Karen [Univ. of Maryland, College Park, MD (United States). Dept. of Chemistry and Biochemistry; Eichhorn, Bryan [Univ. of Maryland, College Park, MD (United States). Dept. of Chemistry and Biochemistry; Wang, Chunsheng [Univ. of Maryland, College Park, MD (United States). Dept. of Chemical and Biomolecular Engineering

    2013-05-01

    Sodium-sulfur batteries, offering high capacity and low cost, are promising alternative to lithium-ion batteries for large-scale energy storage applications. The conventional sodium-sulfur batteries, operating at a high temperature of 300–350°C in a molten state, could lead to severe safety problems. However, the room temperature sodium-sulfur batteries using common organic liuid electrolytes still face a significant challenge due to the dissolution of intermediate sodium polysulfides. For this study, we developed room temperatue sodium-sulfur batteries using a unique porous carbon/sulfur (C/S) composite cathode, which was synthesized by infusing sulfur vapor into porous carbon sphere particles at a high temperatrure of 600°C. The porous C/S composites delivered a reversible capacity of ~860 mAh/g and retained 83% after 300 cycles. The Coulombic efficiency of as high as 97% was observed over 300 cycles. The superior electrochemical performance is attrbuted to the super sulfur stability as evidenced by its lower sensitivity to probe beam irradiation in TEM, XPS and Raman charaterization and high evaperation temperature in TGA. The results make it promising for large-scale grid energy storage and electric vehicles.

  7. REMOVAL OF ANIONIC SURFACTANTS FROM WASTEWATER BY MAGNETIC MINERAL SORBENTS

    Directory of Open Access Journals (Sweden)

    Oksana Vladimirova Makarchuk

    2016-07-01

    Full Text Available The simplest and most effective method of removing low concentrations of anionic surfactants such as sodium dodecyl benzenesulfonate (SDBS and sodium lauryl sulfate (SLS is adsorption. Among adsorbents the natural clays are cheap and promising for these purposes. However, there are significant difficulties in removal of spent sorbent after the adsorption process. So, the creation of magnetic sorbents that can be effectively removed from water after sorption by magnetic separation will be a successful decision. The aim of this investigation is the creation of cheap and efficient magnetic sorbents based on natural clays and magnetite for anionic surfactant removal from wastewater. We have synthesized a series of magnetic sorbents from different natural clays with a content of magnetite from 2 to 10 wt%. The ability of magnetic sorbents to remove SDBS and SLS from aqueous solutions has been studied for different adsorbate concentrations by varying the amount of adsorbent, temperature and shaking time. Thermodynamic parameters were calculated from the slope and intercept of the linear plots of ln K against 1/T. Analysis of adsorption results obtained at different temperatures showed that the adsorption pattern on magnetic sorbents correspond to the Langmuir isotherm. It is shown that with increasing the content of magnetite in the magnetic sorbents improves not only their separation from water by magnetic separation, but adsorption capacity to SDBS and SLS. Thus, we obtained of cheap magnetic sorbents based on natural clays and magnetite by the easy way, which not only quickly separated from the solution by magnetic separation, but effectively remove anionic surfactants.

  8. Bench-scale studies on capture of mercury on mineral non-carbon based sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Li, Yang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion; Utah Univ., Salt Lake City, UT (United States). Dept. of Chemical Engineering; Wendt, Jost O.L. [Utah Univ., Salt Lake City, UT (United States). Dept. of Chemical Engineering; Zhang, Junying; Zheng, Chuguang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

    2013-07-01

    A new high-temperature, mineral non-carbon based dispersed sorbent derived from paper recycling products has been shown to capture mercury at high temperatures in excess of 600 C. The sorbent is consisted of kaolinite/calcite/lime mixtures. Experiments have been conducted on chemi-sorption of elemental mercury in air on a packed bed. The sorption occurs at temperatures between 600 and 1,100 C and requires activation of the minerals contained within the sorbents. Mercury capture is dominated by temperature and capture on sorbents over long time scales. The capture shows a maximum effectiveness at 1,000 C and increases monotonically with temperature. The presence of oxygen is also the required. Freshly activated sorbent is the most effective, and deactivation of sorbents occurs at high temperatures with long pre-exposure times. This activation is suspected to involve a solid-solid reaction between intimately mixed calcium oxide and silica that are both contained within the sorbent. Deactivation occurs at temperatures higher than 1,000 C, and this is due to melting of the substrate and pore closure. The situation in packed beds is complicated because the bed also shrinks, thus allowing channeling and by-passing, and consequent ambiguities in determining sorbent saturation. Sorbent A had significantly greater capacity for mercury sorption than did Sorbent B, for all temperatures and exposure time examined. The effect of SiO{sub 2} on poor Sorbent B is much larger than sorbent A.

  9. Application of inorganic sorbents for sewage purification from copper

    International Nuclear Information System (INIS)

    Yelizarova, I.A.; Tomchuk, T.K.; Kalinin, N.F.; Vol'khin, V.V.; Levichek, M.S.; Gulyaeva, E.I.

    1986-01-01

    Article presents the results of elaboration of synthesis methods of sorbent on the base of phosphate and magnesium hydroxide. As a result of study the technology of sorbent production with optimal properties was elaborated.

  10. Yolk-Shelled C@Fe3 O4 Nanoboxes as Efficient Sulfur Hosts for High-Performance Lithium-Sulfur Batteries.

    Science.gov (United States)

    He, Jiarui; Luo, Liu; Chen, Yuanfu; Manthiram, Arumugam

    2017-09-01

    Owing to the high theoretical specific capacity (1675 mA h g -1 ) and low cost, lithium-sulfur (Li-S) batteries offer advantages for next-generation energy storage. However, the polysulfide dissolution and low electronic conductivity of sulfur cathodes limit the practical application of Li-S batteries. To address such issues, well-designed yolk-shelled carbon@Fe 3 O 4 (YSC@Fe 3 O 4 ) nanoboxes as highly efficient sulfur hosts for Li-S batteries are reported here. With both physical entrapment by carbon shells and strong chemical interaction with Fe 3 O 4 cores, this unique architecture immobilizes the active material and inhibits diffusion of the polysulfide intermediates. Moreover, due to their high conductivity, the carbon shells and the polar Fe 3 O 4 cores facilitate fast electron/ion transport and promote continuous reactivation of the active material during the charge/discharge process, resulting in improved electrochemical utilization and reversibility. With these merits, the S/YSC@Fe 3 O 4 cathodes support high sulfur content (80 wt%) and loading (5.5 mg cm -2 ) and deliver high specific capacity, excellent rate capacity, and long cycling stability. This work provides a new perspective to design a carbon/metal-oxide-based yolk-shelled framework as a high sulfur-loading host for advanced Li-S batteries with superior electrochemical properties. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Peat hybrid sorbents for treatment of wastewaters and remediation of polluted environment

    Science.gov (United States)

    Klavins, Maris; Burlakovs, Juris; Robalds, Artis; Ansone-Bertina, Linda

    2015-04-01

    For remediation of soils and purification of polluted waters, wastewaters, sorbents might be considered as an prospective group of materials and amongst them peat have a special role due to low cost, biodegradability, high number of functional groups, well developed surface area and combination of hydrophilic/hydrophobic structural elements. Peat as sorbent have good application potential for removal of trace metals, and we have demonstrated peat sorption capacities, sorption kinetics, thermodynamics in respect to metals with different valencies - Tl(I), Cu(II), Cr(III). However peat sorption capacity in respect to nonmetallic (anionic species) elements is low. Also peat mechanical properties do not support application in large scale column processes. To expand peat application possibilities the approach of biomass based hybrid sorbents has been elaborated. The concept "hybrid sorbent" in our understanding means natural, biomass based sorbent modified, covered with another sorbent material, thus combining two types of sorbent properties, sorbent functionalities, surface properties etc. As the "covering layer" both inorganic substances, mineral phases (iron oxohydroxides, oxyapatite) both organic polymers (using graft polymerization) were used. The obtained sorbents were characterised by their spectral properties, surface area, elemental composition. The obtained hybrid sorbents were tested for sorption of compounds in anionic speciation forms, for example of arsenic, antimony, tellurium and phosphorous compounds in comparison with weakly basic anionites. The highest sorption capacity was observed when peat sorbents modified with iron compounds were used. Sorption of different arsenic speciation forms onto iron-modified peat sorbents was investigated as a function of pH and temperature. It was established that sorption capacity increases with a rise in temperature, and the calculation of sorption process thermodynamic parameters indicates the spontaneity of sorption

  12. Characterization of calcium carbonate sorbent particle in furnace environment

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Kang Soo [Aerosol and Particle Technology Laboratory, Department of Mechanical Engineering, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of); Jung, Jae Hee [Environment Sensor System Research Center, KIST 39-1 Hawolgok-dong, Seongbuk-gu, Seoul, 136-791 (Korea, Republic of); Keel, Sang In; Yun, Jin Han; Min, Tai Jin [Environmental Systems Research Division, KIMM 104 Sinseongno, Yuseong-gu, Daejeon, 305-343 (Korea, Republic of); Kim, Sang Soo, E-mail: sskim@kaist.ac.kr [Aerosol and Particle Technology Laboratory, Department of Mechanical Engineering, KAIST 291 Daehak-ro, Yuseong-gu, Daejeon, 305-701 (Korea, Republic of)

    2012-07-01

    The oxy-fuel combustion system is a promising technology to control CO{sub 2} and NO{sub X} emissions. Furthermore, sulfation reaction mechanism under CO{sub 2}-rich atmospheric condition in a furnace may lead to in-furnace desulfurization. In the present study, we evaluated characteristics of calcium carbonate (CaCO{sub 3}) sorbent particles under different atmospheric conditions. To examine the physical/chemical characteristics of CaCO{sub 3}, which is used as a sorbent particle for in-furnace desulfurization in the oxy-fuel combustion system, they were injected into high temperature drop tube furnace (DTF). Experiments were conducted at varying temperatures, residence times, and atmospheric conditions in a reactor. To evaluate the aerosolizing characteristics of the CaCO{sub 3} sorbent particle, changes in the size distribution and total particle concentration between the DTF inlet and outlet were measured. Structural changes (e.g., porosity, grain size, and morphology) of the calcined sorbent particles were estimated by BET/BJH, XRD, and SEM analyses. It was shown that sorbent particles rapidly calcined and sintered in the air atmosphere, whereas calcination was delayed in the CO{sub 2} atmosphere due to the higher CO{sub 2} partial pressure. Instead, the sintering effect was dominant in the CO{sub 2} atmosphere early in the reaction. Based on the SEM images, it was shown that the reactions of sorbent particles could be explained as a grain-subgrain structure model in both the air and CO{sub 2} atmospheres.

  13. Characterization of calcium carbonate sorbent particle in furnace environment

    International Nuclear Information System (INIS)

    Lee, Kang Soo; Jung, Jae Hee; Keel, Sang In; Yun, Jin Han; Min, Tai Jin; Kim, Sang Soo

    2012-01-01

    The oxy-fuel combustion system is a promising technology to control CO 2 and NO X emissions. Furthermore, sulfation reaction mechanism under CO 2 -rich atmospheric condition in a furnace may lead to in-furnace desulfurization. In the present study, we evaluated characteristics of calcium carbonate (CaCO 3 ) sorbent particles under different atmospheric conditions. To examine the physical/chemical characteristics of CaCO 3 , which is used as a sorbent particle for in-furnace desulfurization in the oxy-fuel combustion system, they were injected into high temperature drop tube furnace (DTF). Experiments were conducted at varying temperatures, residence times, and atmospheric conditions in a reactor. To evaluate the aerosolizing characteristics of the CaCO 3 sorbent particle, changes in the size distribution and total particle concentration between the DTF inlet and outlet were measured. Structural changes (e.g., porosity, grain size, and morphology) of the calcined sorbent particles were estimated by BET/BJH, XRD, and SEM analyses. It was shown that sorbent particles rapidly calcined and sintered in the air atmosphere, whereas calcination was delayed in the CO 2 atmosphere due to the higher CO 2 partial pressure. Instead, the sintering effect was dominant in the CO 2 atmosphere early in the reaction. Based on the SEM images, it was shown that the reactions of sorbent particles could be explained as a grain–subgrain structure model in both the air and CO 2 atmospheres.

  14. Sorption of agrochemical model compounds by sorbent materials containing beta-cyclodextrin.

    Science.gov (United States)

    Wilson, Lee D; Mohamed, Mohamed H; Guo, Rui; Pratt, Dawn Y; Kwon, Jae Hyuck; Mahmud, Sarker T

    2010-04-01

    Polymeric sorbent materials that incorporate beta-cyclodextrin (CD) have been prepared and their sorption behavior toward two model agrochemical contaminant compounds, p-nitrophenol (PNP) and methyl chloride examined. The sorption of PNP was studied in aqueous solution using ultraviolet-visible (UV-Vis) spectroscopy, whereas the sorption of methyl chloride from the gas phase was studied using a Langmuir adsorption method. The sorption results for PNP in solution were compared between granular activated carbon (GAC), modified GAC, CD copolymers, and CD-based mesoporous silica hybrid materials. Nitrogen porosimetry at 77 K was used to estimate the surface area and pore structure properties of the sorbent materials. The sorbents displayed variable surface areas as follows: copolymers (36.2-157 m(2)/g), CD-silica materials (307-906 m(2)/g), surface modified GAC (657 m(2)/g), and granular activated carbon (approximately 10(3) m(2)/g). The sorption capacities for PNP and methyl chloride with the different sorbents are listed in descending order as follows: GAC > copolymers > surface modified GAC > CD-silica hybrid materials. In general, the differences in the sorption properties of the sorbents were related to the following: (i) surface area of the sorbent, (ii) CD content and accessibility, (iii) and the chemical nature of the sorbent material.

  15. Desulfurization Sorbents for Transport-Bed Applications

    International Nuclear Information System (INIS)

    Gupta, Raghubir P.; Turk, Brian S.; Vierheilig, Albert A.

    1997-01-01

    This project extends the prior work on the development of fluidizable zinc titanate particles using a spray-drying technique to impart high reactivity and attrition resistance. The specific objectives are: (1) To develop highly reactive and attrition-resistant zinc titanate sorbents in 40- to 150-(micro)m particle size range for transport reactor applications; (2) To transfer sorbent production technology to private sector; and (3) To provide technical support to Sierra Pacific Clean Coal Technology Demonstration plant and FETC's Hot-Gas Desulfurization Process Development Unit (PDU), both employing a transport reactor system

  16. Simulation of mercury capture by sorbent injection using a simplified model.

    Science.gov (United States)

    Zhao, Bingtao; Zhang, Zhongxiao; Jin, Jing; Pan, Wei-Ping

    2009-10-30

    Mercury pollution by fossil fuel combustion or solid waste incineration is becoming the worldwide environmental concern. As an effective control technology, powdered sorbent injection (PSI) has been successfully used for mercury capture from flue gas with advantages of low cost and easy operation. In order to predict the mercury capture efficiency for PSI more conveniently, a simplified model, which is based on the theory of mass transfer, isothermal adsorption and mass balance, is developed in this paper. The comparisons between theoretical results of this model and experimental results by Meserole et al. [F.B. Meserole, R. Chang, T.R. Carrey, J. Machac, C.F.J. Richardson, Modeling mercury removal by sorbent injection, J. Air Waste Manage. Assoc. 49 (1999) 694-704] demonstrate that the simplified model is able to provide good predictive accuracy. Moreover, the effects of key parameters including the mass transfer coefficient, sorbent concentration, sorbent physical property and sorbent adsorption capacity on mercury adsorption efficiency are compared and evaluated. Finally, the sensitive analysis of impact factor indicates that the injected sorbent concentration plays most important role for mercury capture efficiency.

  17. Comparative DNA isolation behaviours of silica and polymer based sorbents in batch fashion: monodisperse silica microspheres with bimodal pore size distribution as a new sorbent for DNA isolation.

    Science.gov (United States)

    Günal, Gülçin; Kip, Çiğdem; Eda Öğüt, S; İlhan, Hasan; Kibar, Güneş; Tuncel, Ali

    2018-02-01

    Monodisperse silica microspheres with bimodal pore-size distribution were proposed as a high performance sorbent for DNA isolation in batch fashion under equilibrium conditions. The proposed sorbent including both macroporous and mesoporous compartments was synthesized 5.1 μm in-size, by a "staged shape templated hydrolysis and condensation method". Hydrophilic polymer based sorbents were also obtained in the form of monodisperse-macroporous microspheres ca 5.5 μm in size, with different functionalities, by a developed "multi-stage microsuspension copolymerization" technique. The batch DNA isolation performance of proposed material was comparatively investigated using polymer based sorbents with similar morphologies. Among all sorbents tried, the best DNA isolation performance was achieved with the monodisperse silica microspheres with bimodal pore size distribution. The collocation of interconnected mesoporous and macroporous compartments within the monodisperse silica microspheres provided a high surface area and reduced the intraparticular mass transfer resistance and made easier both the adsorption and desorption of DNA. Among the polymer based sorbents, higher DNA isolation yields were achieved with the monodisperse-macroporous polymer microspheres carrying trimethoxysilyl and quaternary ammonium functionalities. However, batch DNA isolation performances of polymer based sorbents were significantly lower with respect to the silica microspheres.

  18. Sulfur metabolism in phototrophic sulfur bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Dahl, Christiane

    2008-01-01

    Phototrophic sulfur bacteria are characterized by oxidizing various inorganic sulfur compounds for use as electron donors in carbon dioxide fixation during anoxygenic photosynthetic growth. These bacteria are divided into the purple sulfur bacteria (PSB) and the green sulfur bacteria (GSB......). They utilize various combinations of sulfide, elemental sulfur, and thiosulfate and sometimes also ferrous iron and hydrogen as electron donors. This review focuses on the dissimilatory and assimilatory metabolism of inorganic sulfur compounds in these bacteria and also briefly discusses these metabolisms...... in other types of anoxygenic phototrophic bacteria. The biochemistry and genetics of sulfur compound oxidation in PSB and GSB are described in detail. A variety of enzymes catalyzing sulfur oxidation reactions have been isolated from GSB and PSB (especially Allochromatium vinosum, a representative...

  19. Evaluation of 137Cs sorbents for fixation in concrete

    International Nuclear Information System (INIS)

    Plodinec, M.J.

    1976-01-01

    As part of the long-term waste management program at the Savannah River Laboratory, several 137 Cs sorbents were evaluated for incorporation into concrete. The sorbents studied were: Linde AW-300, AW-500, 13-X, and SK-40; Norton Zeolon 200, 500, and 900; clinoptilolite; and vermiculite. The parameters studied were sorption kinetics, leachability, and compressive strength of the concrete. The best sorbents identified were Linde AW-500 and Norton Zeolon 900. In all tests, these two sorbents performed almost identically; sorption kinetics were acceptable; both strengthened the concrete, and both gave relatively leach-resistant concrete. Vermiculite that had been heated to collapse its lattice around 137 Cs gave the most leach-resistant concrete. However, it sorbed cesium slowly, and the resulting concrete was very weak. When silica gel was added to concrete to react with free calcium, the addition had no effect on cesium leachability

  20. Dual layer hollow fiber sorbents: Concept, fabrication and characterization

    KAUST Repository

    Bhandari, Dhaval

    2013-02-01

    Hollow fiber sorbents are pseudo-monolithic separations materials created with fiber spinning technology using a polymer \\'binder\\', impregnated with high loadings of sorbent \\'fillers\\' [1]. To increase purified gas recovery during the sorption step and to ensure consistent sorption capacity over repeated cycles, a dense, thin polymer barrier layer on the fiber sorbents is needed to allow only thermal interactions between the sorbate loaded layer and the thermal regeneration fluid. This paper considers materials and methods to create delamination-free dual layer fiber sorbents, with a porous core and a barrier sheath layer formed using a simultaneous co-extrusion process. Low permeability polymers were screened for sheath layer creation, with the core layer comprising cellulose acetate polymer as binder and zeolite NaY as sorbent fillers. Appropriate core and sheath layer dope compositions were determined by the cloud-point method and rheology measurements. The morphology of the as-spun fibers was characterized in detail by SEM, EDX and gas permeation analysis. A simplified qualitative model is described to explain the observed fiber morphology. The effects of core, sheath spin dope and bore fluid compositions, spinning process parameters such as air-gap height, spin dope and coagulation bath temperatures, and elongation draw ratio are examined in detail. © 2012 Elsevier B.V. All rights reserved.

  1. Topical Report 5: Sorbent Performance Report

    Energy Technology Data Exchange (ETDEWEB)

    Krutka, Holly; Sjostrom, Sharon

    2011-05-31

    ADA-ES has completed an extensive sorbent screening program funded primarily through DOE NETL cooperative agreement DE-NT0005649 with support from EPRI and industry cost-share participants. Tests were completed on simulated and actual flue gas. The overall project objective is to address the viability and accelerate development of a solid-based postcombustion CO2 capture technology that can be retrofit to the existing fleet of coal-fired power plants. An important component of the viability assessment was to evaluate the state of development of sorbents and measure key performance characteristics under realistic operating conditions.

  2. Sorption of europium (3) by polymer sorbents with grafted heterocyclic nitrogen-containing groupings

    International Nuclear Information System (INIS)

    Bel'tyukova, S.V.; Kravchenko, T.B.; Balamtsarashvili, G.M.; Roska, A.S.

    1990-01-01

    On polymer sorbents (copolymer of styrene-divinylbenzene) with grafted heterocyclic nitrogen-containing functional groupings of tetrazole, triazole and imidazole (sorbents 1,2,3, respectively). It is stated that europium sorption takes place from neutral solutions in presence of organic solvents. Luminescent properties of europium on sorbent are used to develope methods of its determination in high purity lanthanide and yttrium oxides. Europium determination limits consist 7.5·10 -5 μg/ml on 1 and 3 sorbents and 1.5·10 -4 μg/ml on sorbent 2, S p value is 0.089 and 0.075, respectivaly

  3. Tunable polymeric sorbent materials for fractionation of model naphthenates.

    Science.gov (United States)

    Mohamed, Mohamed H; Wilson, Lee D; Headley, John V

    2013-04-04

    The sorption properties are reported for several examples of single-component carboxylic acids representing naphthenic acids (NAs) with β-cyclodextrin (β-CD) based polyurethane sorbents. Seven single-component examples of NAs were chosen with variable z values, carbon number, and chemical structure as follows: 2-hexyldecanoic acid (z = 0 and C = 16; S1), n-caprylic acid (z = 0 and C = 8; S2), trans-4-pentylcyclohexanecarboxylic acid (z = -2 and C = 12; S3), 4-methylcyclohexanecarboxylic acid (z = -2 and C = 8; S4), dicyclohexylacetic acid (z = -4; C = 14; S5), 4-pentylbicyclo[2.2.2]octane-1-carboxylic acid (z = -4; C = 14; S6), and lithocholic acid (z = -6; C = 24; S7). The copolymer sorbents were synthesized at three relative β-CD:diisocyanate mole ratios (i.e., 1:1, 1:2, and 1:3) using 4,4'-dicyclohexylmethane diisocyanate (CDI) and 4,4'-diphenylmethane diisocyanate (MDI). The sorption properties of the copolymer sorbents were characterized using equilibrium sorption isotherms in aqueous solution at pH 9.00 with electrospray ionization mass spectrometry. The equilibrium fraction of the unbound carboxylate anions was monitored in the aqueous phase. The sorption properties of the copolymer sorbents (i.e., Qm) were obtained from the Sips isotherm model. The Qm values generally decrease as the number of accessible β-CD inclusion sites in the copolymer framework decreases. The chemical structure of the adsorbates played an important role in their relative uptake, as evidenced by the adsorbate lipophilic surface area (LSA) and the involvement of hydrophobic effects. The copolymers exhibit molecular selective sorption of the single-component carboxylates in mixtures which suggests their application as sorbents for fractionation of mixtures of NAs. By comparison, granular activated carbon (GAC) and chitosan sorbents did not exhibit any significant molecular selective sorption relative to the copolymer materials; however, evidence of variable sorption capacity was

  4. Iron-montmorillonite clays as active sorbents for the decontamination of hazardous chemical warfare agents.

    Science.gov (United States)

    Carniato, F; Bisio, C; Evangelisti, C; Psaro, R; Dal Santo, V; Costenaro, D; Marchese, L; Guidotti, M

    2018-02-27

    A class of heterogeneous catalysts based on commercial bentonite from natural origin, containing at least 80 wt% of montmorillonite clay, was designed to transform selectively and under mild conditions toxic organosulfur and organophosphorus chemical warfare agents into non-noxious products with a reduced impact on health and environment. The bentonite from the natural origin was modified by introducing iron species and acid sites in the interlayer space, aiming to obtain a sorbent with strong catalytic oxidising and hydrolytic properties. The catalytic performance of these materials was evaluated in the oxidative abatement of (2-chloroethyl)ethyl sulfide (CEES), a simulant of sulfur mustard, in the presence of aqueous hydrogen peroxide as an oxidant. A new decontamination formulation was, moreover, proposed and obtained by mixing sodium perborate, as a solid oxidant, to iron-bentonite catalysts. Solid-phase decontamination tests, performed on a cotton textile support contaminated with organosulfide and organophosphonate simulant agents revealed the good activity of the solid formulation, especially in the in situ detoxification of blistering agents. Tests carried out on the real blistering warfare agent, sulfur mustard (HD agent), showed that, thanks to the co-presence of the iron-based clay together with the solid oxidant component, a good decontamination of the test surface from the real warfare agent could be achieved (80% contaminant degradation, under ambient conditions, in 24 h).

  5. Synthesis and test of sorbents based on calcium aluminates for SE-SR

    International Nuclear Information System (INIS)

    Barelli, L.; Bidini, G.; Di Michele, A.; Gallorini, F.; Petrillo, C.; Sacchetti, F.

    2014-01-01

    Highlights: • Synthesis strategy of CaO incorporation into calcium aluminates was approached. • Three innovative sorbents (M1, M2, M3) were synthesized and characterized. • Sorption capacity of developed sorbents was evaluated in multi-cycle processes. • M3 sorbent showed best performance, much higher than conventional CaO ones. • M3 sorbent functionality in SE-SR process was verified. - Abstract: Greenhouse gases emission of power generation plants will be continuously tightened to achieve European targets in terms of CO 2 emissions. In particular, the switching to a sustainable power generation using fossil fuels will be strongly encouraged in the future. In this context, sorption-enhanced steam reforming (SE-SR) is a promising process because it can be implemented as a CCS pre-combustion methodology. The purpose of this study is to develop and test innovative materials in order to overcome main limitations of standard CaO sorbent, usually used in the SE-SR process. The investigated innovative sorbents are based on incorporation of CaO particles into inert materials which significantly reduce the performance degradation. In particular, sorbent materials based on calcium aluminates were considered, investigating different techniques of synthesis. All synthesized materials were packed, together with the catalyst, in a fixed bed reactor and tested in sorption/regeneration cycles. Significant improvements were obtained respect to standard CaO regarding sorption capacity stability exhibited by the sorbent

  6. Cross-linked poly(tetrahydrofuran) as promising sorbent for organic solvent/oil spill

    Energy Technology Data Exchange (ETDEWEB)

    Yati, Ilker; Ozan Aydin, Gulsah; Bulbul Sonmez, Hayal, E-mail: hayalsonmez@gtu.edu.tr

    2016-05-15

    Highlights: • Poly(tetrahydrofuran) based sorbents were prepared. • PTHF sorbents demonstrate reusability at least for ten times. • PTHF based sorbents show fast and quick absorption-desorption process. • 19 g of oil can be absorbed by 1 g of PTHF based sorbent. - Abstract: In this study, a series of different molecular weights of poly(tetrahydrofuran) (PTHF), which is one of the most important commercial polymers around the world, was condensed with tris[3-(trimethoxysilyl)propyl]isocyanurate (ICS) to generate a cross-linked 3-dimensional network in order to obtain organic solvent/oil sorbents having high swelling capacity. The prepared sorbents show high and fast swelling capacity in oils such as dichloromethane (DCM), tetrahydrofuran (THF), acetone, t-butyl methyl ether (MTBE), gasoline, euro diesel, and crude oil. The recovery of the absorbed oils from contaminated surfaces, especially from water, and the regeneration of the sorbents after several applications are effective. The characterization and thermal properties of the sorbents are identified by Fourier transform infrared spectroscopy (FTIR), solid-state {sup 13}C and {sup 29}Si cross-polarization magic angle spinning (CPMAS) nuclear magnetic resonance (NMR), differential scanning calorimetry (DSC) and thermal gravimetric analyses (TGA), respectively. The new usage area of PTHF is emerged by the preparation of PTHF-based network structure with high oil absorption capacity and having excellent reusability as an oil absorbent for the removal of organic liquids from the spill site.

  7. IMMOBILIZATION OF MICROALGAE ON THE SURFACE OF NEW CROSS-LINKED POLYETHYLENIMINE-BASED SORBENTS.

    Science.gov (United States)

    Vasilieva, Svetlana; Shibzukhova, Karina; Morozov, Alexey; Solovchenko, Alexei; Bessonov, Ivan; Kopitsyna, Maria; Lukyanov, Alexander; Chekanov, Konstantin; Lobakova, Elena

    2018-04-11

    We report on the use of the polyethylenimine-based (PEI) sorbents for immobilization and harvesting of microalgae (MA) cells. Specific materials assessed were porous solid polymers from highly-branched PEI synthesized by cross-linking with epichlorohydrin (ECH) or diethylene glycol diglycidyl ether (DGDE). We estimated the effect of PEI/cross-linker ratio on the MA attachment and biocompatibility of the sorbents with the MA cells. A decrease in the cross-linker percentage resulted in the enhancement of the immobilization efficiency but impaired the cell viability as was manifested by inhibition of the photosynthetic activity of the MA cells. The rate of Chlorella vulgaris cell attachment to the sorbents with ECH was faster as compared to that of the PEI-DGDE-based polymers. The cells immobilized on the PEI-ECH sorbents showed a more profound decline in their viability (assessed via photosynthetic activity). The sorbents with 60% of DGDE were characterized by high immobilization efficiency. These sorbents supported a prolonged cultivation of the immobilized MA without impairing their viability and metabolic activity. We conclude that the sorbents with a lower percentage of DGDE (<30%) and sorbents with ECH are suitable for harvesting of the MA cells intended for immediate downstream processing, potentially without the cell desorption. To the best of our knowledge, this is the first report on successful application of PEI-based sorbents in microalgal biotechnology. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Adsorption of Ammonia on Regenerable Carbon Sorbents

    Science.gov (United States)

    Wójtowicz, Marek A.; Cosgrove, Jesph E.; Serio, Michael A..; Wilburn, Monique

    2015-01-01

    Results are presented on the development of reversible sorbents for the combined carbon dioxide, moisture, and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The currently available life support systems use separate units for carbon dioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Data on sorption and desorption of ammonia, which is a major TC of concern, are presented in this paper. The current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is non-regenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. In this study, several carbon sorbents were fabricated and tested for ammonia sorption. Ammonia-sorption capacity was related to carbon pore structure characteristics, and the temperature of oxidative carbon-surface treatment was optimized for enhanced ammonia-sorption performance.

  9. Oil spill sorbents: Testing protocol and certification listing program

    International Nuclear Information System (INIS)

    Cooper, D.; Gausemel, I.

    1993-01-01

    Environment Canada's Emergencies Engineering Division is spearheading a program in conjunction with the Canadian General Standards Board that would see the development of a certification and listing program in addition to a national standard for the testing of sorbent materials. Funding for this program is provided by Environment Canada (EC), Canadian Coast Guard (CCG), Marine Spill Response Corporation (MSRC), US Coast Guard (USCG), and US Minerals Management Service (MMS). The test methods are based upon those defined by the American Society for Testing and Materials and previous test methods developed by Environment Canada for our series of reports entitled Selection Criteria and Laboratory Evaluation of Oil Spill Sorbents. This series, which was started in 1975, encompasses a number of commercially available oil spill sorbents tested with different petroleum products and hydrocarbon solvents. The testing program will categorize the sorbents according to their operating characteristics. The main categories are oil spills on water, oil spills on land, and industrial use. The characteristics to be evaluated with the new test protocols include initial and maximum sorption capacities, water pickup, buoyancy, reuse potential, retention profile, disintegration (material integrity), and ease of application and retrieval. In the near future are plans to incorporate changes to the test that would involve increasing the list of test liquids to encompass spills in an industrial setting, in addition to testing sorbent booms and addressing the disposal problem

  10. Cheap carbon sorbents produced from lignite by catalytic pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Kuznetsov, B.N.; Schchipko, M.L. [Inst. of Chemistry of Natural Organic Materials, Akademgorodok, Krasnoyarsk (Russian Federation)

    1995-12-01

    Some data are presented describing the new technology of carbon sorbent production from powdered lignite in the installation with fluidized bed of catalyst. It was shown the different types of char products with extended pore structure and high sorption ability can be produced from cheap and accessible lignite of Kansk-Achinsk coal pit in pilot installation with fluidized bed of Al-Cu-Cr oxide catalyst or catalytically active slag materials. In comparison with the conventional technologies of pyrolysis the catalytic pyrolysis allows to increase by 3-5 times the process productivity and to decrease significantly the formation of harmful compounds. The latter is accomplished by complete oxidation of gaseous pyrolysis products in the presence of catalysts and by avoiding the formation of pyrolysis tars - the source of cancerogenic compounds. The technology of cheap powdered sorbent production from lignites makes possible to obtain from lignite during the time of pyrolysis only a few seconds char products with porosity up to 0.6 cm{sup 3} /g, and specific surface area more than 400 m{sup 3} /g. Some methods of powdered chars molding into carbon materials with the different shape were proved for producing of firmness sorbents. Cheap carbon sorbents obtained by thermocatalytic pyrolysis can be successfully used in purification of different industrial pollutants as one-time sorbent or as adsorbents of long-term application with periodic regeneration.

  11. Activation and characterization of waste coffee grounds as bio-sorbent

    Science.gov (United States)

    Mariana; Marwan; Mulana, F.; Yunardi; Ismail, T. A.; Hafdiansyah, M. F.

    2018-03-01

    As the city well known for its culture of coffee drinkers, modern and traditional coffee shops are found everywhere in Banda Aceh, Indonesia. High number of coffee shops in the city generates large quantities of spent coffee grounds as waste without any effort to convert them as other valuable products. In an attempt to reduce environmental problems caused by used coffee grounds, this research was conducted to utilize waste coffee grounds as an activated carbon bio-sorbent. The specific purpose of this research is to improve the performance of coffee grounds bio-sorbent through chemical and physical activation, and to characterize the produced bio-sorbent. Following physical activation by carbonization, a chemical activation was achieved by soaking the carbonized waste coffee grounds in HCl solvent and carbonization process. The activated bio-sorbent was characterized for its morphological properties using Scanning Electron Microscopy (SEM), its functional groups by Fourier Transform Infra-Red Spectrophotometer (FTIR), and its material characteristics using X-Ray Diffraction (XRD). Characterization of the activated carbon prepared from waste coffee grounds shows that it meets standard quality requirement in accordance with Indonesian National Standard, SNI 06-3730-1995. Activation process has modified the functional groups of the waste coffee grounds. Comparing to natural waste coffee grounds, the resulted bio-sorbent demonstrated a more porous surface morphology following activation process. Consequently, such bio-sorbent is a potential source to be used as an adsorbent for various applications.

  12. Chitosan-ferrocyanide sorbent for Cs-137 removal from mineralized alkaline media

    Energy Technology Data Exchange (ETDEWEB)

    Egorin, Andrei [Far Eastern Federal Univ., Vladivostok (Russian Federation); Institute of Chemistry FEBRAS, Vladivostok (Russian Federation); Ozyorsk Technical Institute MEPHI, Ozersk (Russian Federation); Tokar, Eduard [Far Eastern Federal Univ., Vladivostok (Russian Federation); Zemskova, Larisa [Institute of Chemistry FEBRAS, Vladivostok (Russian Federation)

    2016-11-01

    An organomineral sorbent based on mixed nickel-potassium ferrocyanide and chitosan to be used in removal of Cs-137 radionuclide from highly mineralized media with high pH has been fabricated. The synthesized sorbent was applied to remove Cs-137 from model solutions under static and dynamic conditions. The effects of contact time, pH, and presence of sodium ions and complexing agents in the process of Cs-137 removal have been investigated. The sorbent is distinguished by increased stability to the impact of alkaline media containing complexing agents, whereas the sorbent capacity in solutions with pH 11 exceeds 1000 bed volumes with the Cs-137 removal efficiency higher than 95%.

  13. Application of fibrous complexing sorbents for trace elements preconcentration and separation

    International Nuclear Information System (INIS)

    Zakhartchenko, E.A.; Myasoedova, G.V.

    2003-01-01

    This article demonstrates the application of the 'filled' fibrous sorbents for preconcentration and separation of platinum metals, as well as heavy metals and radionuclides. The POLYORGS complexing sorbents and ion-exchangers were used as fillers. Dynamic preconcentration conditions should be set for complete sorption of the elements: diameter and mass of the sorbent disk or the column as well as flow rate of the solution. These conditions depend on specific features of materials to be analysed and the requirements of the experimental task or detection method. Extensive alteration of features as well as perfect kinetic properties and high selectivity of the 'filled' sorbents confirm their applicability for trace elements preconcentration and separation in technology and analytical chemistry. (authors)

  14. Sorbent application on the base of chitosan for radionuclides separation

    International Nuclear Information System (INIS)

    Pivarciova, L.

    2016-01-01

    Radioactive waste contains enormous amounts of radionuclides, which pollute the environment and can cause serious chemical and radiological toxicity threats to lower and higher living organism. Alternative process for the removal of heavy metal ions and radionuclides is sorption, which utilizes various certain natural materials of biological origin. Amino-polysaccharide-based sorbents e.g. chitosan represent suitable materials for binding of metal oxo-anion species because of numerous functional groups -OH and -NH_2 because of their suitable H-bond donor and acceptor sites. The sorbents on the base chitosan prepared through chemical modification were used for removal and separation certain radionuclides from aqueous media. The aim of this work was the study of physicochemical properties of prepared sorbents. The specific surface of sorbents was characterized with BET methods. Point of zero charge was identified with potentiometric titration. The size of particles and shape of sorbents were determined by scanning electron microscope. The sorption experiments for selected radionuclides were conducted under static and dynamic conditions. The effect of various parameters on the sorption "9"9"mTc, "6"0Co and the effect of pH on the separation of radionuclide mixture in the solution were studied. (author)

  15. Synthesis of hydroxide type sorbents from industry high-iron wastes

    International Nuclear Information System (INIS)

    Stepanenko, E.K.; Smirnov, A.L.

    1986-01-01

    Article presents the results of studies on possibility of using of technological iron containing wastes for the obtaining of hydroxide type sorbents in granular form. The scheme of technology of synthesis of hydroxide type sorbents from high-iron wastes is elaborated.

  16. SORBENT/UREA SLURRY INJECTION FOR SIMULTANEOUS SO2/NOX REMOVAL

    Science.gov (United States)

    The combination of sorbent injection and selective noncatalytic reduction (SNCR) technologies has been investigated for simulataneous SO2/NOx removal. A slurry composed of a urea-based solution and various Ca-based sorbents was injected at a range of tempera...

  17. MERCURY CONTROL WITH CALCIUM-BASED SORBENTS AND OXIDIZING AGENTS

    Energy Technology Data Exchange (ETDEWEB)

    Thomas K. Gale

    2002-06-01

    The initial tasks of this DOE funded project to investigate mercury removal by calcium-based sorbents have been completed, and initial testing results have been obtained. Mercury monitoring capabilities have been obtained and validated. An approximately 1MW (3.4 Mbtu/hr) Combustion Research Facility at Southern Research Institute was used to perform pilot-scale investigations of mercury sorbents, under conditions representative of full-scale boilers. The initial results of ARCADIS G&M proprietary sorbents, showed ineffective removal of either elemental or oxidized mercury. Benchscale tests are currently underway to ascertain the importance of differences between benchscale and pilot-scale experiments. An investigation of mercury-capture temperature dependence using common sorbents has also begun. Ordinary hydrated lime removed 80 to 90% of the mercury from the flue gas, regardless of the temperature of injection. High temperature injection of hydrated lime simultaneously captured SO{sub 2} at high temperatures and Hg at low temperatures, without any deleterious effects on mercury speciation. Future work will explore alternative methods of oxidizing elemental mercury.

  18. Sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides

    Directory of Open Access Journals (Sweden)

    R.V. Smotraiev

    2016-05-01

    Full Text Available The actual problem of water supply in the world and in Ukraine, in particular, is a high level of pollution in water resources and an insufficient level of drinking water purification. With industrial wastewater, a significant amount of pollutants falls into water bodies, including suspended particles, sulfates, iron compounds, heavy metals, etc. Aim: The aim of this work is to determine the impact of aluminum and manganese ions additives on surface and sorption properties of zirconium oxyhydroxide based sorbents during their production process. Materials and Methods: The sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were prepared by sol-gel method during the hydrolysis of metal chlorides (zirconium oxychloride ZrOCl2, aluminum chloride AlCl3 and manganese chloride MnCl2 with carbamide. Results: The surface and sorption properties of sorbents based on xerogels of zirconium, aluminum and manganese oxyhydroxides were investigated. X-ray amorphous structure and evolved hydroxyl-hydrate cover mainly characterize the obtained xerogels. The composite sorbents based on xerogels of zirconium oxyhydroxide doped with aluminum oxyhydroxide (aS = 537 m2/g and manganese oxyhydroxide (aS = 356 m2/g have more developed specific surface area than single-component xerogels of zirconium oxyhydroxide (aS = 236 m2/g and aluminum oxyhydroxide (aS = 327 m2/g. The sorbent based on the xerogel of zirconium and manganese oxyhydroxides have the maximum SO42--ions sorption capacity. It absorbs 1.5 times more SO42–-ions than the industrial anion exchanger AN-221. The sorbents based on xerogels of zirconium oxyhydroxide has the sorption capacity of Fe3+-ions that is 1.5…2 times greater than the capacity of the industrial cation exchanger KU-2-8. The Na+-ions absorption capacity is 1.47…1.56 mmol/g for each sorbent. Conclusions: Based on these data it can be concluded that the proposed method is effective for sorbents production based on

  19. Development of New Potassium Carbonate Sorbent for CO2 Capture under Real Flue Gas Conditions

    Directory of Open Access Journals (Sweden)

    Javad Esmaili

    2014-07-01

    Full Text Available In this paper, the development of a new potassium carbonateon alumina support sorbent prepared by impregnating K2CO3 with an industrial grade of Al2O3 support was investigated. The CO2 capture capacity was measured using real flue gas with 8% CO2 and 12% H2O in a fixed-bed reactor at a temperature of 65 °C using breakthrough curves. The developed sorbent showed an adsorption capacity of 66.2 mgCO2/(gr sorbent. The stability of sorbent capture capacity was higher than the reference sorbent. The SO2 impurity decreased sorbent capacity about 10%. The free carbon had a small effect on sorbent capacity after 5 cycles. After 5 cycles of adsorption and regeneration, the changes in the pore volume and surface area were 0.020 cm3/gr and 5.5 m2/gr respectively. Small changes occurred in the pore size distribution and surface area of sorbent after 5 cycles.

  20. Regenerable sorbents for mercury capture in simulated coal combustion flue gas.

    Science.gov (United States)

    Rodríguez-Pérez, Jorge; López-Antón, M Antonia; Díaz-Somoano, Mercedes; García, Roberto; Martínez-Tarazona, M Rosa

    2013-09-15

    This work demonstrates that regenerable sorbents containing nano-particles of gold dispersed on an activated carbon are efficient and long-life materials for capturing mercury species from coal combustion flue gases. These sorbents can be used in such a way that the high investment entailed in their preparation will be compensated for by the recovery of all valuable materials. The characteristics of the support and dispersion of gold in the carbon surface influence the efficiency and lifetime of the sorbents. The main factor that determines the retention of mercury and the regeneration of the sorbent is the presence of reactive gases that enhance mercury retention capacity. The capture of mercury is a consequence of two mechanisms: (i) the retention of elemental mercury by amalgamation with gold and (ii) the retention of oxidized mercury on the activated carbon support. These sorbents were specifically designed for retaining the mercury remaining in gas phase after the desulfurization units in coal power plants. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Dual layer hollow fiber sorbents for trace H2S removal from gas streams

    KAUST Repository

    Bhandari, Dhaval A.; Bessho, Naoki; Koros, William J.

    2013-01-01

    Hollow fiber sorbents are pseudo monolithic materials with potential use in various adsorption based applications. Dual layer hollow fiber sorbents have the potential to allow thermal regeneration without direct contact of the regeneration fluid with the sorbent particles. This paper considers the application of dual layer hollow fiber sorbents for a case involving trace amounts of H2S removal from a simulated gas stream and offers a comparison with single layer hollow fiber sorbents. The effect of spin dope composition and core layer zeolite loading on the gas flux, H2S transient sorption capacity and pore structure are also studied. This work can be used as a guide to develop and optimize dual layer hollow fiber sorbent properties beyond the specific example considered here. © 2013 Elsevier Ltd.

  2. Dual layer hollow fiber sorbents for trace H2S removal from gas streams

    KAUST Repository

    Bhandari, Dhaval A.

    2013-05-01

    Hollow fiber sorbents are pseudo monolithic materials with potential use in various adsorption based applications. Dual layer hollow fiber sorbents have the potential to allow thermal regeneration without direct contact of the regeneration fluid with the sorbent particles. This paper considers the application of dual layer hollow fiber sorbents for a case involving trace amounts of H2S removal from a simulated gas stream and offers a comparison with single layer hollow fiber sorbents. The effect of spin dope composition and core layer zeolite loading on the gas flux, H2S transient sorption capacity and pore structure are also studied. This work can be used as a guide to develop and optimize dual layer hollow fiber sorbent properties beyond the specific example considered here. © 2013 Elsevier Ltd.

  3. CaO-Based CO2 Sorbents Effectively Stabilized by Metal Oxides.

    Science.gov (United States)

    Naeem, Muhammad Awais; Armutlulu, Andac; Imtiaz, Qasim; Müller, Christoph R

    2017-11-17

    Calcium looping (i.e., CO 2 capture by CaO) is a promising second-generation CO 2 capture technology. CaO, derived from naturally occurring limestone, offers an inexpensive solution, but due to the harsh operating conditions of the process, limestone-derived sorbents undergo a rapid capacity decay induced by the sintering of CaCO 3 . Here, we report a Pechini method to synthesize cyclically stable, CaO-based CO 2 sorbents with a high CO 2 uptake capacity. The sorbents synthesized feature compositional homogeneity in combination with a nanostructured and highly porous morphology. The presence of a single (Al 2 O 3 or Y 2 O 3 ) or bimetal oxide (Al 2 O 3 -Y 2 O 3 ) provides cyclic stability, except for MgO which undergoes a significant increase in its particle size with the cycle number. We also demonstrate a direct relationship between the CO 2 uptake and the morphology of the synthesized sorbents. After 30 cycles of calcination and carbonation, the best performing sorbent, containing an equimolar mixture of Al 2 O 3 and Y 2 O 3 , exhibits a CO 2 uptake capacity of 8.7 mmol CO 2  g -1 sorbent, which is approximately 360 % higher than that of the reference limestone. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Coating membranes for a sorbent-based artificial liver: adsorption characteristics

    NARCIS (Netherlands)

    de Koning, H. W.; Chamuleau, R. A.; Bantjes, A.

    1982-01-01

    Techniques are described for the coating of sorbents to be used in an artificial liver support system based on mixed sorbent bed hemoperfusion. Activated charcoal has been coated with cellulose acetate (CA) by solvent evaporation. With Amberlite XAD-4, the Wurster technique was used for coating with

  5. Application of magnetic sorbent in the removal of cadmium from soils

    Directory of Open Access Journals (Sweden)

    Michal Lovás

    2006-12-01

    Full Text Available A contamination of soil by heavy metals is a common problem at many metalliferous mining sites. There are various treatment processes for the cleanup of soil contaminated with heavy metals. A method designed for the decontamination of soil polluted by Cd is described. The method utilizes a magnetic sorbent – sludges from the hydrometallurgic processing of nickel mineral, activated by milling. The influence of sorbent concentration, pH and microwave energy on the sorption capacity and content of Cd ions in a soil was studed. The effectiveness of Cd desorption from the soil was 75 %, the maximal sorption capacity of sorbent was 9,8 mg/g. The content of Cd in water is function of pH and the concentration of sorbent. The influence of microwave energy (90 W was negligible.

  6. Sorbents based on carbonized rice peel

    International Nuclear Information System (INIS)

    Mansurova, R. M.; Taipova, R. A.; Zhylybaeva, N. K.; Mansurov, Z. A.; Bijsenbaev, M. A.

    2004-01-01

    The process receiving of sorbents based on carbonized rice peel (RP) was received and their sorption properties were investigated. Processing carbonization of samples leading on station, this was developed in laboratory of hybrid technology. Carbonization of samples was realized in nitric atmosphere on 400-8000 deg. C. On raising temperature of carbonization content of carbon in samples is rice, hydrogen and oxygen is reduce as a result isolation of volatility products is discover. The samples carbonized on 650 deg. C (910 m 2 /g) owners with maximum removed surface is discover. On carbonization temperature 600-800 deh. C the sorption of ions, which carbonized by sorbents based on rice peel is run to 95-100 %. Electron-microscopic investigation of samples leaded on EM-125 mechanism by accelerating pressure 100 kV. From electron-microscopic print of original samples of RP it is evident, that sample consists of carbonic fractions of different species: carbonic fiber of rounded fractions, fractions of ellipsoid form and of more thickly carbonic structure. Increasing sizes of pores and modification structure of synthesized sorbent is occur during carbonization process. The RP-samples, which carbonized by 650 deg. C has the higher specific surface. Samples consist of thin carbonic scum and reducing specific surface, by higher temperature

  7. Preparation and characterisation of a sorbent suitable for technetium separation from environmental matrices

    International Nuclear Information System (INIS)

    Bartosova, A.; Rajec, P.; Reich, M.

    2003-01-01

    A sorbent based on Aliquat 336 anchored on hydrophobised silica gel support as an ion exchanger was prepared. Prepared sorbent was suitable for separation of technetium-99 from environmental matrices. The sorbent properties, sorption characteristic and distribution coefficient of 99 mTcO 4 - in various medium was studied. The chemical yield of Tc during separation process was determined using 99m Tc tracer and gamma measurement. Typical sorption recoveries of Tc for this sorbent from 0.1 M HNO 3 were more than 98 %. Typical desorption recoveries using 8 M HNO 3 were in the range 92 - 96 %. The commercial TEVA Spec resin from Eichrom Industries for comparison purpose was used as well. It was found that the prepared sorbent is suitable for separation of technetium from environmental matrices. (authors)

  8. Low-Cost Sorbents: A Literature Summary

    National Research Council Canada - National Science Library

    Bailey, Susan

    1997-01-01

    The capital and regeneration costs of activated carbon and ion exchange media suggest that better process economics may be achieved with disposable sorbents for the treatment of metals-contaminated...

  9. Hydroxyapatite-based sorbents: elaboration, characterization and application for the removal of catechol from the aqueous phase.

    Science.gov (United States)

    Sebei, Haroun; Pham Minh, Doan; Lyczko, Nathalie; Sharrock, Patrick; Nzihou, Ange

    2017-10-01

    Hydroxyapatite (HAP) is highly considered as good sorbent for the removal of metals from the aqueous phase. However, soluble metals co-exist with organic pollutants in wastewaters. But little work has been devoted to investigate the reactivity of HAP for the removal of organic compounds. The main objective of this work is to study the reactivity of HAP-based sorbents for the removal of catechol as a model organic pollutant from an aqueous solution. Thus, HAP sorbents were firstly synthesized using calcium carbonate and potassium dihydrogen phosphate under moderate conditions (25-80°C, atmospheric pressure). A zinc-doped HAP was also used as sorbent, which was obtained from the contact of HAP with an aqueous solution of zinc nitrate. All the sorbents were characterized by different standard physico-chemical techniques. The sorption of catechol was carried out in a batch reactor under stirring at room temperature and pressure. Zinc-doped HAP sorbent was found to be more reactive than non-doped HAP sorbents for the fixation of catechol. The highest sorption capacity was of 15 mg of C per gram of zinc-doped HAP sorbent. The results obtained suggest the reaction scheme of HAP sorbents with metals and organic pollutants when HAP sorbents were used for the treatment of complex wastewaters.

  10. Itaconic acid based potential sorbent for uranium recovery

    International Nuclear Information System (INIS)

    Kalyan, Y.; Naidu, G.R.K.; Das, Sadananda; Pandey, A.K.; Reddy, A.V.R.

    2010-01-01

    Cross-linked hydrogels and adsorptive membranes containing Itaconic acid, Acrylamide, Penta erythritol tetra acrylate and α, α-dimethyl- α-phenyl aceto phenone were prepared by UV-initiated bulk polymerization. These hydrogels and adsorptive membranes were characterized for pH uptake, sorption and desorption kinetics and selectivity towards uranium. The sorption ability of the sorbents towards uranyl ion was thoroughly examined. The developed itaconic acid based sorbents were evaluated for the recovery of uranium from lean sources like sea water. (author)

  11. Experimental research on combustion fluorine retention using calcium-based sorbents during coal combustion (II)

    Energy Technology Data Exchange (ETDEWEB)

    Qi, Q.; Ma, X.; Liu, J.; Wu, X.; Zhou, J.; Cen, K. [Liaoning Technical University, Fuxin (China). College of Resource and Environment Engineering

    2008-12-15

    Fluoride pollution produced by coal burning can be controlled with the calcium-based sorbent combustion fluorine technique in which calcium-based sorbents are mixed with the coal or sprayed into the combustion chamber. In a fixed bed tube furnace combustion experiment using one calcium-based natural mineral, limestone and one calcium-based building material, it was shown that the calcium-based sorbent particle grain size and pore structure have a big influence on the combustion fluorine retention effect. Reducing the calcium-based sorbent particle grain size and improving the calcium sorbent structure characteristics at very high temperature to enhance the fluorine retention effect is the important approach to the fluorine retention agent development. 8 refs., 1 fig., 5 tabs.

  12. Dual functional MoS2/graphene interlayer as an efficient polysulfide barrier for advanced lithium-sulfur batteries

    International Nuclear Information System (INIS)

    Guo, Pengqian; Liu, Dequan; Liu, Zhengjiao; Shang, Xiaonan; Liu, Qiming; He, Deyan

    2017-01-01

    Highlights: •Dual functional MoS 2 /graphene interlayer was first used as an efficient polysulfide-trapping shield for lithium-sulfur batteries. •MoS 2 /graphene interlayer shows strong chemical interactions with LiPSs. •MoS 2 /graphene interlayer forms a 3D network to facilitate electron and ion transfer during the discharge-charge processes. •The resultant lithium-sulfur batteries exhibit a superior rate capacity and improved cycling capacity. -- Abstract: A dual functional interlayer consisted of composited two-dimensional MoS 2 and graphene has been developed as an efficient polysulfide barrier for lithium-sulfur batteries (LSBs). With such a configuration, LSBs show a superior rate capacity and improved cycling capacity. The excellent electrochemical performance can be attributed to the strong bonding interactions between the MoS 2 /graphene interlayer and the formed lithium polysulfides (LiPSs) as well as the good electrical conductivity of the MoS 2 /graphene composite. The MoS 2 /graphene interlayer can physically block LiPSs by the graphene nanosheets and chemically suppress the dissolution of LiPSs by the polar MoS 2 nanoflowers. Such a dual functional interlayer further provides a good contact with the surface of the sulfur cathode, acts as an upper current collector and greatly improves the sulfur utilization and the rate capability of LSBs.

  13. Inorganic sorbents for radiostrontium removal from waste solutions: selectivity and role of calixarenes

    International Nuclear Information System (INIS)

    Vijayan, S.; Belikov, K.; Drapailo, A.

    2011-01-01

    The challenge in the remediation of 90 Sr-contaminated waters arises from the need to achieve very high removal efficiencies to meet discharge targets from waste effluents containing relatively high concentrations of non-radioactive cations. Low-cost natural zeolites are not selective for strontium over other divalent cations, notably such ions as calcium; and produce low 90 Sr removal performance, and large volumes of spent sorbent waste. The synthesis and use of selective, synthetic inorganic sorbents could prove to be a feasible approach for high 90 Sr removal efficiencies, and much smaller volumes of secondary solid waste generation. The essential advantages of inorganic sorbents include their stability and resistance to radiation, and the potential for producing stable waste forms such as vitrified glass or ceramics for disposal. However, the cost of strontium-specific sorbents is prohibitive for large-scale applications at present. This paper is a review of the reported information on removal mechanisms and performance of Sr-specific inorganic sorbents. The analysis has revealed promising performance, efficiency and selectivity for strontium removal from solutions containing low and high concentrations of salts. The leading sorbents are crystalline silicotitanate and oxides of metals such as titanium. An initial assessment has also been made of the performance of calixarene-based macrocyclic compounds. These are known for their selectivity for strontium in solvent extraction processes. From the initial strontium removal results in bench-scale tests using different solid substrates, impregnated with calixarene derivatives, only sodium-mordenite impregnated with calyx[8]arene octamide gave an overall strontium removal efficiency in the range of 90 to 95% in the presence of 3.5 ppm calcium. There was no improvement observed for strontium-removal efficiency or selectivity over calcium in the calixarene-impregnated inorganic sorbent matrix. In several tests, the

  14. The hot gas cleaning with multifunctional sorbent technique at 1-20 bar pressure; Kaasujen kuumapuhdistus multifunktionaalisella sorbenttitekniikalla 1-20 bar:n paineessa

    Energy Technology Data Exchange (ETDEWEB)

    Jaanu, K.; Orjala, M.; Paakkinen, K.; Rantanen, J. [VTT Energy, Espoo (Finland)

    1996-12-01

    The aim of the research was to study the simultaneous hot gas cleanup of alkali metals and selected heavy metals under pressure of 1-20 bar using multifunctional sorbent technology, to investigate effects of it on sulfur and nitrogen emissions and to improve the total efficiency of the hot gas cleanup method by reducing the concentrations of harmful components to the level required by the gas turbines. The research has started in the year 1993. The optimization of the test facility at 900 deg C and 20 bar has been accomplished, as targeted. The main topics have been the alkali metals. The main targets of the year 1994 was to concentrate on the research of sorbent effectiveness to remove the impurities like alkalies etc. from the flue gas. Furthermore researches on kinetics and mechanisms were started. The results showed that the developed multifunctional sorbent are highly effective to remove alkalies from the flue gas. Also a mechanism for alkali and lead sorption was proposed. The main topics for 1995 were scheduled to be the completion of the kinetic and mechanical studies and the modelling and the estimation of the data for the pilot scale unit. The kinetic data for one sorbent has been completed and a model for that has also been developed. The measured and calculated results are indicating that the developed multifunctional sorption process is highly effective to remove alkalies and heavy metals such as lead and cadmium from high-temperature combustion gases. The tests are carried out mainly using the pressurized entrained flow reactor of VTT Energy, located in Jyvaeskylae, and in the university of Arizona, where the tests are conducted under atmospheric pressure. Some comparisons of the results might be made with those of Aabo Akademi during the future modelling. 3. The results are applied to purification of the hot gases in boilers, power and process industry. (Abstract Truncated)

  15. Predicting sorption of organic acids to a wide range of carbonized sorbents

    Science.gov (United States)

    Sigmund, Gabriel; Kah, Melanie; Sun, Huichao; Hofmann, Thilo

    2016-04-01

    Many contaminants and infochemicals are organic acids that undergo dissociation under environmental conditions. The sorption of dissociated anions to biochar and other carbonized sorbents is typically lower than that of neutral species. It is driven by complex processes that are not yet fully understood. It is known that predictive approaches developed for neutral compounds are unlikely to be suitable for organic acids, due to the effects of dissociation on sorption. Previous studies on the sorption of organic acids to soils have demonstrated that log Dow, which describes the decrease in hydrophobicity of acids upon dissociation, is a useful alternative to log Kow. The aim of the present study was to adapt a log Dow based approach to describe the sorption of organic acids to carbonized sorbents. Batch experiments were performed with a series of 9 sorbents (i.e., carbonized wood shavings, pig manure, and sewage sludge, carbon nanotubes and activated carbon), and four acids commonly used for pesticidal and biocidal purposes (i.e., 2,4-D, MCPA, 2,4-DB, and triclosan). Sorbents were comprehensively characterized, including by N2 and CO2 physisorption, Fourier transform infrared spectroscopy, and elemental analysis. The wide range of sorbents considered allows (i) discussing the mechanisms driving the sorption of neutral and anionic species to biochar, and (ii) their dependency on sorbate and sorbent properties. Results showed that the sorption of the four acids was influenced by factors that are usually not considered for neutral compounds (i.e., pH, ionic strength). Dissociation affected the sorption of the four compounds, and sorption of the anions ranged over five orders of magnitude, thus substantially contributing to sorption in some cases. For prediction purposes, most of the variation in sorption to carbonized sorbents (89%) could be well described with a two-parameter regression equation including log Dow and sorbent specific surface area. The proposed model

  16. Advanced Utility Mercury-Sorbent Field-Testing Program

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Landreth

    2007-12-31

    This report summarizes the work conducted from September 1, 2003 through December 31, 2007 on the project entitled Advanced Utility Mercury-Sorbent Field-Testing Program. The project covers the testing at the Detroit Edison St. Clair Plant and the Duke Power Cliffside and Buck Stations. The St. Clair Plant used a blend of subbituminous and bituminous coal and controlled the particulate emissions by means of a cold-side ESP. The Duke Power Stations used bituminous coals and controlled their particulate emissions by means of hot-side ESPs. The testing at the Detroit Edison St. Clair Plant demonstrated that mercury sorbents could be used to achieve high mercury removal rates with low injection rates at facilities that burn subbituminous coal. A mercury removal rate of 94% was achieved at an injection rate of 3 lb/MMacf over the thirty day long-term test. Prior to this test, it was believed that the mercury in flue gas of this type would be the most difficult to capture. This is not the case. The testing at the two Duke Power Stations proved that carbon- based mercury sorbents can be used to control the mercury emissions from boilers with hot-side ESPs. It was known that plain PACs did not have any mercury capacity at elevated temperatures but that brominated B-PAC did. The mercury removal rate varies with the operation but it appears that mercury removal rates equal to or greater than 50% are achievable in facilities equipped with hot-side ESPs. As part of the program, both sorbent injection equipment and sorbent production equipment was acquired and operated. This equipment performed very well during this program. In addition, mercury instruments were acquired for this program. These instruments worked well in the flue gas at the St. Clair Plant but not as well in the flue gas at the Duke Power Stations. It is believed that the difference in the amount of oxidized mercury, more at Duke Power, was the difference in instrument performance. Much of the equipment was

  17. Evaluation of inorganic sorbent treatment for LWR coolant process streams

    International Nuclear Information System (INIS)

    Roddy, J.W.

    1984-03-01

    This report presents results of a survey of the literature and of experience at selected nuclear installations to provide information on the feasibility of replacing organic ion exchangers with inorganic sorbents at light-water-cooled nuclear power plants. Radioactive contents of the various streams in boiling water reactors and pressurized water reactors were examined. In addition, the methods and performances of current methods used for controlling water quality at these plants were evaluated. The study also includes a brief review of the physical and chemical properties of selected inorganic sorbents. Some attributes of inorganic sorbents would be useful in processing light water reactor (LWR) streams. The inorganic resins are highly resistant to damage from ionizing radiation, and their exchange capacities are generally equivalent to those of organic ion exchangers. However, they are more limited in application, and there are problems with physical integrity, especially in acidic solutions. Research is also needed in the areas of selectivity and anion removal before inorganic sorbents can be considered as replacements for the synthetic organic resins presently used in LWRs. 11 figures, 14 tables

  18. Efficient CO2 sorbents based on silica foam with ultra-large mesopores

    KAUST Repository

    Qi, Genggeng; Fu, Liling; Choi, Brian Hyun; Giannelis, Emmanuel P.

    2012-01-01

    A series of high-capacity, amine impregnated sorbents based on a cost-effective silica foam with ultra-large mesopores is reported. The sorbents exhibit fast CO2 capture kinetics, high adsorption capacity (of up to 5.8 mmol g-1 under 1 atm of dry CO2), as well as good stability over multiple adsorption-desorption cycles. A simple theoretical analysis is provided relating the support structure to sorbent performance. © 2012 The Royal Society of Chemistry.

  19. Evaluation of Dry Sorbent Injection Technology for Pre-Combustion CO{sub 2} Capture

    Energy Technology Data Exchange (ETDEWEB)

    Richardson, Carl [URS Group, Inc., Austin, TX (United States); Steen, William [URS Group, Inc., Austin, TX (United States); Triana, Eugenio [URS Group, Inc., Austin, TX (United States); Machalek, Thomas [URS Group, Inc., Austin, TX (United States); Davila, Jenny [URS Group, Inc., Austin, TX (United States); Schmit, Claire [URS Group, Inc., Austin, TX (United States); Wang, Andrew [URS Group, Inc., Austin, TX (United States); Temple, Brian [URS Group, Inc., Austin, TX (United States); Lu, Yongqi [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Lu, Hong [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Zhang, Luzheng [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Ruhter, David [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Rostam-Abadi, Massoud [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Sayyah, Maryam [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Ito, Brandon [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States); Suslick, Kenneth [Illinois State Geological Survey - University of Illinois at Urbana-Champaign (United States)

    2013-09-30

    This document summarizes the work performed on Cooperative Agreement DE-FE0000465, “Evaluation of Dry Sorbent Technology for Pre-Combustion CO{sub 2} Capture,” during the period of performance of January 1, 2010 through September 30, 2013. This project involves the development of a novel technology that combines a dry sorbent-based carbon capture process with the water-gas-shift reaction for separating CO{sub 2} from syngas. The project objectives were to model, develop, synthesize and screen sorbents for CO{sub 2} capture from gasified coal streams. The project was funded by the DOE National Energy Technology Laboratory with URS as the prime contractor. Illinois Clean Coal Institute and The University of Illinois Urbana-Champaign were project co-funders. The objectives of this project were to identify and evaluate sorbent materials and concepts that were suitable for capturing carbon dioxide (CO{sub 2}) from warm/hot water-gas-shift (WGS) systems under conditions that minimize energy penalties and provide continuous gas flow to advanced synthesis gas combustion and processing systems. Objectives included identifying and evaluating sorbents that efficiently capture CO{sub 2} from a gas stream containing CO{sub 2}, carbon monoxide (CO), and hydrogen (H{sub 2}) at temperatures as high as 650 °C and pressures of 400-600 psi. After capturing the CO{sub 2}, the sorbents would ideally be regenerated using steam, or other condensable purge vapors. Results from the adsorption and regeneration testing were used to determine an optimal design scheme for a sorbent enhanced water gas shift (SEWGS) process and evaluate the technical and economic viability of the dry sorbent approach for CO{sub 2} capture. Project work included computational modeling, which was performed to identify key sorbent properties for the SEWGS process. Thermodynamic modeling was used to identify optimal physical properties for sorbents and helped down-select from the universe of possible sorbent

  20. Development of composite calcium hydroxide sorbent in mechanical operations and evaluation of its basic sorption properties

    Directory of Open Access Journals (Sweden)

    Gara Paweł

    2017-01-01

    Full Text Available This article presents the results of research carried out on the possibility of obtaining composite calcium hydroxide sorbent in the process of two-step granulation, containing additional compounds of Al, Mg and Fe, and their textural and sorption studies. For this purpose, attempts were undertaken to compact commercial calcium hydroxide powder with six additives in the laboratory roll press. The resulting compacts were crushed and sieved in order to achieve the assumed sieve fraction. Based on the obtained results, basic parameters of the process of formation of composite sorbent have been determined. Both, the selected composite sorbents fractions and additives were subsequently subjected to textural studies (determination of the specific surface area and porosity and sorption capacity performance. In addition, for the better interpretation of the results, thermogravimetric studies were carried out both for the additives and composite sorbents, as well as the grain size distribution of the additives. The results of the physicochemical tests of the obtained composite sorbents were compared with analogic results from the study on fine-grained hydroxide sorbent without additives and carbonate sorbent. The presented results showed that in a two-step granulation process it is possible to obtain the granular Ca(OH2 sorbent, as well as composite sorbents possessing better SO2 sorption capacity in comparison to the powder Ca(OH2 and/or to the calcium carbonate sorbent. This can be attributed to the combination of capability of the sorbent to appropriate thermal decomposition and the formation of a group of pores in the range of 0.07-0.3 microns.

  1. Graphene-sulfur nanocomposites for rechargeable lithium-sulfur battery electrodes

    Science.gov (United States)

    Liu, Jun; Lemmon, John P; Yang, Zhenguo; Cao, Yuiliang; Li, Xiaolin

    2014-06-17

    Rechargeable lithium-sulfur batteries having a cathode that includes a graphene-sulfur nanocomposite can exhibit improved characteristics. The graphene-sulfur nanocomposite can be characterized by graphene sheets with particles of sulfur adsorbed to the graphene sheets. The sulfur particles have an average diameter less than 50 nm..

  2. High capacity carbon dioxide sorbent

    Science.gov (United States)

    Dietz, Steven Dean; Alptekin, Gokhan; Jayaraman, Ambalavanan

    2015-09-01

    The present invention provides a sorbent for the removal of carbon dioxide from gas streams, comprising: a CO.sub.2 capacity of at least 9 weight percent when measured at 22.degree. C. and 1 atmosphere; an H.sub.2O capacity of at most 15 weight percent when measured at 25.degree. C. and 1 atmosphere; and an isosteric heat of adsorption of from 5 to 8.5 kilocalories per mole of CO.sub.2. The invention also provides a carbon sorbent in a powder, a granular or a pellet form for the removal of carbon dioxide from gas streams, comprising: a carbon content of at least 90 weight percent; a nitrogen content of at least 1 weight percent; an oxygen content of at most 3 weight percent; a BET surface area from 50 to 2600 m.sup.2/g; and a DFT micropore volume from 0.04 to 0.8 cc/g.

  3. Decontamination formulation with sorbent additive

    Science.gov (United States)

    Tucker; Mark D. , Comstock; Robert H.

    2007-10-16

    A decontamination formulation and method of making that neutralizes the adverse health effects of both chemical and biological compounds, especially chemical warfare (CW) and biological warfare (BW) agents, and toxic industrial chemicals. The formulation provides solubilizing compounds that serve to effectively render the chemical and biological compounds, particularly CW and BW compounds, susceptible to attack, and at least one reactive compound that serves to attack (and detoxify or kill) the compound. The formulation includes at least one solubilizing agent, a reactive compound, a bleaching activator, a sorbent additive, and water. The highly adsorbent, water-soluble sorbent additive (e.g., sorbitol or mannitol) is used to "dry out" one or more liquid ingredients, such as the liquid bleaching activator (e.g., propylene glycol diacetate or glycerol diacetate) and convert the activator into a dry, free-flowing powder that has an extended shelf life, and is more convenient to handle and mix in the field.

  4. DEVELOPMENT OF DISPOSABLE SORBENTS FOR CHLORIDE REMOVAL FROM HIGH TEMPERATURE COAL-DERIVED GASES

    Energy Technology Data Exchange (ETDEWEB)

    Gopala Krishnan; Raghubir Gupta

    1999-09-01

    Advanced integrated-gasification combined-cycle (IGCC) and integrated-gasification fuel cell (IGFC) systems require the development of high temperature sorbents for the removal of hydrogen chloride (HCl) vapor to less than 1 parts-per-million (ppm) levels. HCl is a highly reactive, corrosive, and toxic gas which must be removed to meet environmental regulations, to protect power generation equipment, and to minimize deterioration of hot gas desulfurization sorbents. The objective of this program was to develop disposable, alkali-based sorbents capable of reducing HCl vapor levels to less than 1 ppm in the temperature range from 400 to 750 C and pressures in the range from 1 to 20 atm. The primary areas of focus of this program were to investigate different methods of sorbent fabrication, testing their suitability for different reactor configurations, obtaining reaction kinetics data, and conducting a preliminary economic feasibility assessment. This program was a joint effort between SRI International (SRI), Research Triangle Institute (RTI), and General Electric Corporate Research and Development (GE-CRD). SRI, the prime contractor and RTI, a major subcontractor, performed most of the work in this program. Thermochemical calculations indicated that sodium-based sorbents were capable of reducing HCl vapor levels to less than 1 ppm at temperatures up to 650 C, but the regeneration of spent sorbents would require complex process steps. Nahcolite (NaHCO{sub 3}), a naturally-occurring mineral, could be used as an inexpensive sorbent to remove HCl vapor in hot coal gas streams. In the current program, nahcolite powder was used to fabricate pellets suitable for fixed-bed reactors and granules suitable for fluidized-bed reactors. Pilot-scale equipment were used to prepare sorbents in large batches: pellets by disk pelletization and extrusion techniques, and granules by granulation and spray-drying techniques. Bench-scale fixed- and fluidized-bed reactors were assembled at

  5. Thermochemical Characterizations of Novel Vermiculite-LiCl Composite Sorbents for Low-Temperature Heat Storage

    Directory of Open Access Journals (Sweden)

    Yannan Zhang

    2016-10-01

    Full Text Available To store low-temperature heat below 100 °C, novel composite sorbents were developed by impregnating LiCl into expanded vermiculite (EVM in this study. Five kinds of composite sorbents were prepared using different salt concentrations, and the optimal sorbent for application was selected by comparing both the sorption characteristics and energy storage density. Textural properties of composite sorbents were obtained by extreme-resolution field emission scanning electron microscopy (ER-SEM and an automatic mercury porosimeter. After excluding two composite sorbents which would possibly exhibit solution leakage in practical thermal energy storage (TES system, thermochemical characterizations were implemented through simulative sorption experiments at 30 °C and 60% RH. Analyses of thermogravimetric analysis/differential scanning calorimetry (TGA/DSC curves indicate that water uptake of EVM/LiCl composite sorbents is divided into three parts: physical adsorption of EVM, chemical adsorption of LiCl crystal, and liquid–gas absorption of LiCl solution. Energy storage potential was evaluated by theoretical calculation based on TGA/DSC curves. Overall, EVMLiCl20 was selected as the optimal composite sorbent with water uptake of 1.41 g/g, mass energy storage density of 1.21 kWh/kg, and volume energy storage density of 171.61 kWh/m3.

  6. Lead, Chromium and Cadmium Removal from Contaminated Water Using Phosphate Sorbents

    Directory of Open Access Journals (Sweden)

    Fariborz Riahi

    2010-06-01

    Full Text Available Sorption of 3 poisonous metal ions (Pb2+, Cd2+, Cr3+ in aqueous solutions by two phosphate sorbents under dynamic and static conditions was studied. Phosphate sorbents (MgNH4PO4. H2O, Mg3(PO42. 6H2O were synthesized by known procedures. The resulting crystalline samples were analyzed for the contents of Mg2+, Pb2+, P, N using spectrophotometric and elemental analysis methods. Likewise, the amounts of Pb2+, Cd2+, Cr3+ in solutions were determined before and after the sorption process using the atomic absorption method. The relative standard deviations for Pb2+, Cd2+, Cr3+ were 4.7%, 2.17%, and 1.61% and the detection limits were 5 g/L, 0.05 mg/L, and 0.1 mg/L, respectively. The sorbents showed a high performance in the purification of contaminated solutions under static conditions. The sorption capacity levels of Mg3 (PO42. 6H2O and MgNH4 PO4. H2O were 9.8m.mol/gr and 8.9m.mol/gr for Pb2+; 10.5m.mol/gr and 9m.mol/gr for Cd2+; and 6.6m.mol/gr and 5.3m.mol/gr for Cr3+, respectively. Pb2+ , Cd2+, Cr3+. sorption by inorganic phosphate sorbents from solutions is associated with complicated chemical transformations of the sorbents. A proper account of these transformations allows for the sorption process to be optimized. The data on Pb2+, Cd2+, Cr3+ sorption under static conditions (24-h contact of Mg3 (PO42. 6H2O, MgNH4PO4. H2O, with solutions at 20oC and under dynamic conditions were obtained and the sorption behaviors of the metal ions were investigated in response to the sorbents used. It was found that Mg3 (PO42. 6H2O was the best sorbent for Pb2+, Cd2+, Cr3+ under dynamic conditions.

  7. Sorption of short-lived radionuclides in a layer of sorbent with spherical granules

    International Nuclear Information System (INIS)

    Karlin, Yu.V.

    1993-01-01

    Sorption methods have found wide application in the purification of liquid radioactive wastes. The working element in sorption methods for this purpose is usually a sorption column with a fixed layer of sorbent. Continuous-action equipment with a moving layer of sorbent is very seldom used. When a fixed layer of sorbent is used its wear and prolonged mixing in the sorption column are reduced to a minimum, and maximum purification is achieved due to the advantages of the dynamic method of sorption over the static method. The time of protective action of the sorbent layer is determined by the time taken for the radionuclide to pass through the sorption column, and for the majority of radionuclides is determined by numerous parameters, including the type of sorbent and radionuclide, the rate of flow through the sorbent, the size of the sorbent granules, etc. The physical and chemical aspects of this process have been investigated in detail, and numerous methods for modeling it mathematically have been developed and have been used to develop methods of designing sorption column apparatus. The specific nature of the radionuclides as unstable materials enables the hypothetical case of a open-quotes perpetualclose quotes sorption filter to be represented. In fact, to achieve this it is only necessary to assume that the half-life of the radionuclide is so small that the rate of decay of the radionuclide in the sorption column (both in the sorbed state and in the aqueous phase of the sorption layer) is equal to the rate that it is fed into the column in the flow of liquid radioactive waste. In this case the sorption front of the radionuclide in the column wall remains fixed after a certain initial period. In this paper, a mathematical model of such a hypothetical filter for the case of spherical sorbent granules is considered

  8. High temperature CO2 capture using calcium oxide sorbent in a fixed-bed reactor

    International Nuclear Information System (INIS)

    Dou Binlin; Song Yongchen; Liu Yingguang; Feng Cong

    2010-01-01

    The gas-solid reaction and breakthrough curve of CO 2 capture using calcium oxide sorbent at high temperature in a fixed-bed reactor are of great importance, and being influenced by a number of factors makes the characterization and prediction of these a difficult problem. In this study, the operating parameters on reaction between solid sorbent and CO 2 gas at high temperature were investigated. The results of the breakthrough curves showed that calcium oxide sorbent in the fixed-bed reactor was capable of reducing the CO 2 level to near zero level with the steam of 10 vol%, and the sorbent in CaO mixed with MgO of 40 wt% had extremely low capacity for CO 2 capture at 550 deg. C. Calcium oxide sorbent after reaction can be easily regenerated at 900 deg. C by pure N 2 flow. The experimental data were analyzed by shrinking core model, and the results showed reaction rates of both fresh and regeneration sorbents with CO 2 were controlled by a combination of the surface chemical reaction and diffusion of product layer.

  9. Experimental investigation of adsorption of NO and SO2 on modified activated carbon sorbent from flue gases

    International Nuclear Information System (INIS)

    Zhu, J.L.; Wang, Y.H.; Zhang, J.C.; Ma, R.Y.

    2005-01-01

    It is indicated that modified carbon is a practical sorbent for removal of NO and SO 2 from waste gases by the adsorption method. The ideal compositions for the prepared sorbent were 4.0 wt.% and 2.5 wt.% Na 2 CO 3 and KOH at the experimental conditions, respectively, shortened as ACNaK 2.5 . Experimental investigation showed that the sorbent had a comparatively high breakthrough adsorption capacity of NO and SO 2 , about 5.8 g (NO + SO 2 )/100 g sorbent. It is indicated that a relatively high adsorption temperature would benefit the sorbent adsorption capacities on NO and SO 2 at a certain space velocity and pressure. Further study revealed that the ACNaK 2.5 sorbent had good regenerability at the experimental conditions, which implied that the ACNaK 2.5 sorbent would be a useful sorbent for simultaneous removal of NO and SO 2 from waste gases by adsorption

  10. Selective catalytic reduction of sulfur dioxide to elemental sulfur. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Liu, W.; Flytzani-Stephanopoulos, M.; Sarofim, A.F.

    1995-06-01

    This project has investigated new metal oxide catalysts for the single stage selective reduction of SO{sub 2} to elemental sulfur by a reductant, such as CO. Significant progress in catalyst development has been made during the course of the project. We have found that fluorite oxides, CeO{sub 2} and ZrO{sub 2}, and rare earth zirconates such as Gd{sub 2}Zr{sub 2}O{sub 7} are active and stable catalysts for reduction Of SO{sub 2} by CO. More than 95% sulfur yield was achieved at reaction temperatures about 450{degrees}C or higher with the feed gas of stoichiometric composition. Reaction of SO{sub 2} and CO over these catalysts demonstrated a strong correlation of catalytic activity with the catalyst oxygen mobility. Furthermore, the catalytic activity and resistance to H{sub 2}O and CO{sub 2} poisoning of these catalysts were significantly enhanced by adding small amounts of transition metals, such as Co, Ni, Co, etc. The resulting transition metal-fluorite oxide composite catalyst has superior activity and stability, and shows promise in long use for the development of a greatly simplified single-step sulfur recovery process to treat variable and dilute SO{sub 2} concentration gas streams. Among various active composite catalyst systems the Cu-CeO{sub 2} system has been extensively studied. XRD, XPS, and STEM analyses of the used Cu-CeO{sub 2} catalyst found that the fluorite crystal structure of ceria was stable at the present reaction conditions, small amounts of copper was dispersed and stabilized on the ceria matrix, and excess copper oxide particles formed copper sulfide crystals of little contribution to catalytic activity. A working catalyst consisted of partially sulfated cerium oxide surface and partially sulfided copper clusters. The overall reaction kinetics were approximately represented by a first order equation.

  11. Sorbent Nanotechnologies for Water Cleaning

    Science.gov (United States)

    Ahmed, Snober

    Despite decades of regulatory efforts to mitigate water pollution, many chemicals, particularly heavy metals, still present risks to human health. In addition to direct exposure, certain metals such as mercury threaten public health due to its persistence, bioaccumulation and bioamplification throughout the food chain. A number of U.S. Federal and State regulations have been established to reduce the levels of mercury in water. Activated carbon (AC) has been widely explored for the removal of mercury. However, AC suffers from many limitations inherent to its chemical properties, and it becomes increasingly challenging to meet current and future regulations by simply modifying AC to enhance its performance. Recently, the performance of nanosorbents have been studied in order to removal pollutants. Nanosorbents utilize the ultra-high reactive surface of nanoparticles for rapid, effective and even permanent sequestration of heavy metals from water and air, thus showed promising results as compared to AC. The goal of this thesis research is to develop nanomaterial-based sorbents for the removal of mercury from water. It describes the development of a new solid-support assisted growth of selenium nanoparticles, their use for water remediation, and the development of a new nanoselenium-based sorbent sponge for fast and efficient mercury removal. The nanoselenium sorbent not only shows irreversible interaction with mercury but also exhibits remarkable properties by overcoming the limitations of AC. The nanoselenium sponge was shown to remove mercury to undetectable levels within one minute. This new sponge technology would have an impact on inspiring new stringent regulations and lowering costs to help industries meet regulatory requirements, which will ultimately help improve air and water quality, aquatic life and public health.

  12. Qualification of the ALKASORB sorbent for the sorption-enhanced water-gas shift process

    Energy Technology Data Exchange (ETDEWEB)

    Van Selow, E.R.; Cobden, P.D.; Dijk, Van H.A.J.; Walspurger, S.; Verbraeken, P.A.; Jansen, D.

    2013-07-01

    For the sorption-enhanced water-gas shift (SEWGS) process, a new sorbent material has been qualified in a reactor of 2 m length under conditions close to industrial designs. The sorbent ALKASORB is a potassium-carbonate promoted hydrotalcite-based compound. ALKASORB is shown to have many favourable properties in comparison to the reference sorbent, in particular with respect to mechanical stability. The cyclic capacity of the new compound is substantially higher than the cyclic capacity of the reference sorbent, and it allows a reduction of the steam requirement of 50%. The sorbent has demonstrated catalytic activity for the water-gas shift reaction that is sufficient to omit a separate catalyst. It is demonstrated that the sorbent remains chemically and mechanically stable during operation of at least 2000 adsorption-desorption cycles, even in the presence of H2S in the feed. H2S is shown not to influence CO2 adsorption capacity and is co-captured with the CO2. In contrast to the reference material that showed mechanical degradation during extended adsorption-desorption cycles, the new material is stable and allows to obtain carbon capture levels exceeding 95% more efficiently and more economically since the required size of the vessels will be smaller.

  13. Water Utility Lime Sludge Reuse – An Environmental Sorbent ...

    Science.gov (United States)

    Lime sludge can be used as an environmental sorbent to remove sulfur dioxide (SO2) and acid gases, by the ultra-fine CaCO3 particles, and to sequester mercury and other heavy metals, by the Natural Organic Matter and residual activated carbon. The laboratory experimental set up included a simulated flue gas preparation unit, a lab-scale wet scrubber, and a mercury analyzer system. The influent mercury concentration was based on a range from 22 surveyed power plants. The reactivity of the lime sludge sample for acid neutralization was determined using a method similar to method ASTM C1318-95. Similar experiments were conducted using reagent calcium carbonate and calcium sulfate to obtain baseline data for comparing with the lime sludge test results. The project also evaluated the techno-economic feasibility and sustainable benefits of reusing lime softening sludge. If implemented on a large scale, this transformative approach for recycling waste materials from water treatment utilities at power generation utilities for environmental cleanup can save both water and power utilities millions of dollars. Huge amounts of lime sludge waste, generated from hundreds of water treatment utilities across the U.S., is currently disposed in landfills. This project evaluated a sustainable and economically-attractive approach to the use of lime sludge waste as a valuable resource for power generation utilities.

  14. Waste Derived Sorbents and Their Potential Roles in Heavy Metal Remediation Applications

    Directory of Open Access Journals (Sweden)

    Chiang Y. W.

    2013-04-01

    Full Text Available Inorganic waste materials that have the suitable inherent characteristics could be used as precursors for the synthesis of micro- and mesoporous materials, which present great potential to be re-utilized as sorbent materials for heavy metal remediation. Three inorganic waste materials were studied in the present work: water treatment residuals (WTRs from an integrated drinking water/wastewater treatment plant, and fly ash and bottom ash samples from a municipal solid waste incinerator (MSWI. These wastes were converted into three sorbent materials: ferrihydrite-like materials derived from drying of WTRs, hydroxyapatite-like material derived from ultrasound assisted synthesis of MSWI fly ash with phosphoric acid solution, and a zeolitic material derived from alkaline hydrothermal conversion of MSWI bottom ash. The performance of these materials, as well as their equivalent commercially available counterparts, was assessed for the adsorption of multiple heavy metals (As, Cd, Co, Ni, Pb, Zn from synthetic solutions, contaminated sediments and surface waters; and satisfactory results were obtained. In addition, it was observed that the combination of sorbents into sorbent mixtures enhanced the performance levels and, where applicable, stabilized inherently mobile contaminants from the waste derived sorbents.

  15. HYBRID SULFUR RECOVERY PROCESS FOR NATURAL GAS UPGRADING

    International Nuclear Information System (INIS)

    Girish Srinivas; Steven C. Gebhard; David W. DeBerry

    2001-01-01

    This first quarter report of 2001 describes progress on a project funded by the U.S. Department of Energy (DOE) to test a hybrid sulfur recovery process for natural gas upgrading. The process concept represents a low cost option for direct treatment of natural gas streams to remove H(sub 2)S in quantities equivalent to 0.2-25 metric tons (LT) of sulfur per day. This process is projected to have lower capital and operating costs than the competing technologies, amine/aqueous iron liquid redox and amine/Claus/tail gas treating, and have a smaller plant footprint, making it well suited to both on-shore and offshore applications. CrystaSulf(trademark) (service mark of Gas Research Institute) is a new nonaqueous sulfur recovery process that removes hydrogen sulfide (H(sub 2)S) from gas streams and converts it into elemental sulfur. CrystaSulf features high sulfur recovery similar to aqueous-iron liquid redox sulfur recovery processes, but differs from the aqueous processes in that CrystaSulf controls the location where elemental sulfur particles are formed. In the hybrid process, approximately 1/3 of the total H(sub 2)S in the natural gas is first oxidized to SO(sub 2) at low temperatures over a heterogeneous catalyst. Low temperature oxidation is done so that the H(sub 2)S can be oxidized in the presence of methane and other hydrocarbons without oxidation of the hydrocarbons. The project involves the development of a catalyst using laboratory/bench-scale catalyst testing, and then demonstration of the catalyst at CrystaTech's pilot plant in west Texas. During this reporting periods new catalyst formulations were tested. The experiments showed that the newest catalyst has slightly better performance, but catalyst TDA No.2 is still superior overall for use with the hybrid CrystaSulf process due to lower costs. Plans for catalyst pelletization and continued testing are described

  16. Evaluation of Carbon Dioxide Capture From Existing Coal Fired Plants by Hybrid Sorption Using Solid Sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Steven [Univ. of North Dakota, Grand Forks, ND (United States); Srinivasachar, Srivats [Envergex LLC, Sturbridge, MA (United States); Laudal, Daniel [Univ. of North Dakota, Grand Forks, ND (United States); Browers, Bruce [Barr Engineering, Minneapolis, MN (United States)

    2014-12-31

    A novel hybrid solid sorbent technology for CO₂ capture and separation from coal combustion-derived flue gas was evaluated. The technology – Capture of CO₂ by Hybrid Sorption (CACHYS™) – is a solid sorbent technology based on the following ideas: 1) reduction of energy for sorbent regeneration, 2) utilization of novel process chemistry, 3) contactor conditions that minimize sorbent-CO₂ heat of reaction and promote fast CO₂ capture, and 4) low-cost method of heat management. This report provides key information developed during the course of the project that includes sorbent performance, energy for sorbent regeneration, physical properties of the sorbent, the integration of process components, sizing of equipment, and overall capital and operational cost of the integrated CACHYS™ system. Seven sorbent formulations were prepared and evaluated at the lab-scale for energy requirements and CO₂ capture performance. Sorbent heat of regeneration ranged from 30-80 kJ/mol CO₂ and was found to be dependent on process conditions. Two sorbent formulations (designated HCK-4 & HCK-7) were down-selected for additional fixed-bed testing. Additional testing involved subjecting the sorbents to 100 continuous cycles in the fixed-bed reactor to determine performance as a function of time. The working capacity achieved for HCK-4 sorbent ranged from 5.5-8.0 g CO₂/100 g sorbent, while the HCK-7 typically ranged from 8.0-10.0 g CO₂/100 g sorbent. Overall, there was no deterioration in capacity with continuous cycling for either sorbent. The CACHYS™ bench-scale testing system designed and fabricated under this award consists of a dual circulating fluidized-bed adsorber and a moving-bed regenerator. The system takes a flue gas slipstream from the University of North Dakota’s coal-fired steam plant. Prior to being sent to the adsorber, the flue gas is scrubbed to remove SO₂ and particulate. During parametric testing of the adsorber, CO₂ capture achieved using

  17. New polymer bounces into sorbent market

    International Nuclear Information System (INIS)

    Roy, K.A.

    1991-01-01

    Spectacular spills like the Exxon Valdez capture headlines and dominate conversation, but most releases involve quantities too small to attract media attention. For these spills, companies often rely on sorbents to collect the oil and dispose it. These devices come in a variety of shapes, sizes and absorbent materials, including a new generation of products that offers solid results-literally. This paper reports on the Solidifier which absorbs oil, as well as chlorinated solvents, hydrocarbons and PCBs, and, as the name implies, solidifies into a rubber-like material. A polymer used extensively in the rubber industry is the key to the sorbent's success. Oil and other contaminants, act like catalysts. They dissolve into the polymer, causing its molecules to bond together and form a rubber-like mass. No. 2 diesel fuel oil can be bounced on the floor after it solidifies

  18. AIR SEPARATION BY PRESSURE SWING ADSORPTION USING SUPERIOR ADSORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    Ralph T. Yang

    2001-08-31

    Li-X zeolite (Si/Al = 1.0) is currently the best sorbent for use in the separation of air by adsorption processes. In particular, pressure swing adsorption (PSA) using zeolite sorbents is being increasingly used for air separation. Silver is also known to strongly affect the adsorptive properties of zeolites; and it is known that thermal vacuum dehydration of silver zeolites leads to the formation of silver clusters within the zeolite. In this work we have synthesized type X zeolites containing Ag and also varying mixtures of Li and Ag. In this project, we developed the Ag-containing zeolite as the best sorbent for air separation. We have also studied Co-ligand compounds as oxygen-selective sorbents. Syntheses, structural characterization and adsorption properties have been performed on all sorbents. The results are described in detail in 5 chapters.

  19. Performance analysis of K-based KEP-CO2P1 solid sorbents in a bench-scale continuous dry-sorbent CO{sub 2} capture process

    Energy Technology Data Exchange (ETDEWEB)

    Park, Young Cheol; Jo, Sung-Ho; Lee, Seung-Yong; Moon, Jong-Ho; Yi, Chang-Keun [Korea Institute of Energy Research, 152, Gajeong-ro, Yuseong-gu, Daejeon (Korea, Republic of); Ryu, Chong Kul; Lee, Joong Beom [Korea Electric Power Corporation Research Institute, Daejeon (Korea, Republic of)

    2016-01-15

    Korea Institute of Energy Research (KIER) and Korea Electric Power Corporation Research Institute (KEPCORI) have been developing a CO{sub 2} capture technology using dry sorbents. In this study, KEP-CO2P1, a potassium-based dry sorbent manufactured by a spray-drying method, was used. We employed a bench-scale dry-sorbent CO{sub 2} capture fluidized-bed process capable of capturing 0.5 ton CO{sub 2}/day at most. We investigated the sorbent performance in continuous operation mode with solid circulation between a fast fluidized-bed-type carbonator and a bubbling fluidizedbed- type regenerator. We used a slip stream of a real flue gas from 2MWe coal-fired circulating fluidized-bed (CFB) power facilities installed at KIER. Throughout more than 50 hours of continuous operation, the temperature of the carbonator was maintained around 70-80 .deg. C using a jacket-type heat exchanger, while that of the regenerator was kept above 180 .deg. C using an electric furnace. The differential pressure of both the carbonator and regenerator was maintained at a stable level. The maximum CO{sub 2} removal was greater than 90%, and the average CO{sub 2} removal was about 83% during 50 hours of continuous operation.

  20. Silver nanoparticles embedded polymer sorbent for preconcentration of uranium from bio-aggressive aqueous media

    International Nuclear Information System (INIS)

    Das, Sadananda; Pandey, Ashok K.; Athawale, Anjali A.; Subramanian, M.; Seshagiri, T.K.; Khanna, Pawan K.; Manchanda, Vijay K.

    2011-01-01

    Adsorptive sorbent for bio-aggressive natural aqueous media like seawater was developed by one pot simultaneous synthesis of silver nanoparticles (Ag nps) and poly(ethylene glycol methacrylate phosphate) (PEGMP) by UV-initiator induced photo-polymerization. The photo-polymerization was carried out by irradiating N,N'-dimethylformamide (DMF) solution containing appropriate amounts of the functional monomer (ethylene glycol methacrylate phosphate), UV initiator (α,α'-dimethoxy-α-phenyl acetophenone), and Ag + ions with 365 nm UV light in a multilamps photoreactor. To increase mechanical strength, nano-composite sorbent (Ag-PEGMP) was also reinforced with thermally bonded non-woven poly(propylene) fibrous sheet. Transmission electron microscopy (TEM) of the nano-composite sorbent showed uniform distribution of spherical Ag nanoparticles with particles size ranging from 3 to 6 nm. The maximum amount of Ag 0 that could be anchored in the form of nanoparticles were 5 ± 1 and 10 ± 1 wt.% in self-supported PEGMP and poly(propylene) reinforced PEGMP matrices, respectively. Ag-PEGMP sorbent was found to be stable under ambient conditions for a period of six months. Ag-PEGMP composite sorbent did not exhibit growth at all after incubation with pre-grown Escherichia coli cells, and showed non-adherence of this bacteria to the composite. This indicated that composite sorbent has the bio-resistivity due to bacterial repulsion and bactericidal properties of Ag nanoparticles embedded in the PEGMP. Sorption of U(VI) in PEGMP and Ag-PEGMP nano-composite sorbents from well-stirred seawater was studied to explore the possibility of using it for uranium preconcentration from bio-aggressive aqueous streams. The nano-composite sorbent was used to preconcentrate U(VI) from a process aqueous waste stream.

  1. SO{sub 2} Retention by CaO-Based Sorbent Spent in CO{sub 2} Looping Cycles

    Energy Technology Data Exchange (ETDEWEB)

    Manovic, V.; Anthony, E.J.; Loncarevic, D.

    2009-07-15

    CaO-based looping cycles are promising processes for CO{sub 2} Capture from both syngas and flue gas. The technology is based on cyclical carbonation of CaO and regeneration of CaCO{sub 3} in a dual fluidized-bed reactor to produce a pure CO{sub 2} stream suitable for sequestration. Use of spent sorbent from CO{sub 2} looping cycles for SO{sub 2} capture is investigated. Three limestones were investigated: Kelly Rock (Canada), La Blanca (Spain), and Katowice (Poland, Upper Silesia). Carbonation/calcination cycles were performed in a tube furnace with both the original limestones and samples thermally pretreated for different times (i.e., sintered). The spent sorbent samples were sulfated in a thermogravimetric analyzer (TGA). The changes in the resulting sorbent pore structure were then investigated using mercury porosimetry. It has been shown that the sulfation rates of both thermally pretreated and spent sorbent samples are lower in comparison with those of the original samples. However, final conversions of both spent and pretreated sorbents after longer sulfation time were comparable or higher than those observed for the original sorbents under comparable conditions. Maximum sulfation levels strongly depend on sorbent porosity and pore surface area. The results showed that spent sorbent samples from CO{sub 2} looping cycles can be used as sorbents for SO{sub 2} retention in cases where significant porosity loss does not occur during CO{sub 2} reaction cycles. In the case of spent Kelly Rock and Katowice samples, sorbent particles are practically uniformly sulfated, achieving final conversions that are determined by the total pore volume available for the bulky CaSO{sub 4} product.

  2. Technology assessment guide for application of engineered sorbent barriers to low-level radioactive waste disposal sites

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Jones, E.O.; Depner, J.P.

    1989-06-01

    An engineered sorbent barrier (ESB) uses sorbent materials (such as activated carbon or natural zeolites) to restrict migration of radionuclides from low-level waste sites. The permeability of the ESB allows moisture to pass while the sorbent material traps or absorbs contaminants. In contrast, waste sites with impermeable barriers could fill with water, especially those waste sites in humid climates. A sorbent barrier can be a simple, effective, and inexpensive method for restricting radionuclide migration. This report provides information and references to be used in assessing the sorbent barrier technology for low-level waste disposal. The ESB assessment is based on sorbent material and soil properties, site conditions, and waste properties and inventories. These data are used to estimate the thickness of the barrier needed to meet all performance requirements for the waste site. This document addresses the following areas: (1) site information required to assess the need and overall performance of a sorbent barrier; (2) selection and testing of sorbent materials and underlying soils; (3) use of radionuclide transport models to estimate the required barrier thickness and long-term performance under a variety of site conditions; (4) general considerations for construction and quality assurance; and (5) cost estimates for applying the barrier. 37 refs., 6 figs., 2 tabs.

  3. Cleanup of Savannah River Plant solvent using solid sorbents

    International Nuclear Information System (INIS)

    Mailen, J.C.; Tallent, O.K.

    1985-04-01

    The degradation products produced in Purex solvent by exposure to nitric acid and radiation can be divided into two groups: those which are removed by scrubbing with sodium carbonate solutions and those which are not; these latter materials are called secondary degradation products. This study investigated the use of solid sorbents for removal of the secondary degradation products from first-cycle Savannah River Plant solvent that had been previously washed with sodium carbonate solution. Silica gel, activated charcoal, macroreticular resin, attapulgite clay and activated alumina were the sorbents investigated in preliminary testing. Activated alumina was found to be most effective for improving phase separation of the solvent from sodium carbonate solutions and for increasing the interfacial tension. The activated alumina was also the sorbent most useful for removing complexants which retain plutonium at low acidity, but it was less effective in removing anionic surfactants and ruthenium. We found that the capacity of the activated alumina was greatly improved by drying the solvent before treatment

  4. Radon adsorption in fibrous carbon sorbents

    International Nuclear Information System (INIS)

    Anshakov, O.M.; Kish, A.O.; Chudakov, V.A.; Matvejchuk, S.V.; Sokolovskij, A.S.; Ugolev, I.I.

    2006-01-01

    Radon sorption in woven fibrous sorbents 'AUT-M' and 'Busofit' and nonwoven fiber in the temperature range 0-50 degrees centigrade was studied. Adsorption heat of radon from the ambient air in different types of carbon fiber was determined. (authors)

  5. Experimental investigation of various vegetable fibers as sorbent materials for oil spills.

    Science.gov (United States)

    Annunciado, T R; Sydenstricker, T H D; Amico, S C

    2005-11-01

    Oil spills are a global concern due to their environmental and economical impact. Various commercial systems have been developed to control these spills, including the use of fibers as sorbents. This research investigates the use of various vegetable fibers, namely mixed leaves residues, mixed sawdust, sisal (Agave sisalana), coir fiber (Cocos nucifera), sponge-gourd (Luffa cylindrica) and silk-floss as sorbent materials of crude oil. Sorption tests with crude oil were conducted in deionized and marine water media, with and without agitation. Water uptake by the fibers was investigated by tests in dry conditions and distillation of the impregnated sorbent. The silk-floss fiber showed a very high degree of hydrophobicity and oil sorption capacity of approximately 85goil/g sorbent (in 24hours). Specific gravity measurements and buoyancy tests were also used to evaluate the suitability of these fibers for the intended application.

  6. Experimental investigation of various vegetable fibers as sorbent materials for oil spills

    Energy Technology Data Exchange (ETDEWEB)

    Annunciado, T.R.; Sydenstricker, T.H.D.; Amico, S.C. [Federal University of Parana, Curitiba, (Brazil). Department of Mechanical Engineering

    2005-11-15

    Oil spills are a global concern due to their environmental and economical impact. various commercial systems have been developed to control these spills, including the use of fibers as sorbents. This research investigates the use of various vegetable fibers, namely mixed leaves residues, mixed sawdust, sisal (Agave sisalana), coir fiber (Cocos nucifera), sponge-gourd (Luffa cylindrica) and silk-floss as sorbent materials of crude oil. Sorption tests with crude oil were conducted in deionized and marine water media, with and without agitation. Water uptake by the fibers was investigated by tests in dry conditions and distillation of the impregnated sorbent. The silk-floss fiber showed a very high degree of hydrophobicity and oil sorption capacity of approximately 85 g oil/g sorbent (in 24 hours). Specific gravity measurements and buoyancy tests were also used to evaluate the suitability of these fibers for the intended application. (author)

  7. Effectiveness of liquid radioactive waste purification by inorganic granulated sorbents

    International Nuclear Information System (INIS)

    Komarevskij, V.M.; Stepanets, O.V.; Sharygin, L.M.; Matveev, S.A.

    1995-01-01

    Study results on purification of simulative and real liquid radioactive wastes from fission products radionuclides and by inorganic corrosion-nature sorbents 'Thermoxide' are presented. Properties by sorption of cesium, strontium and cobalt are studied; results of experiments on purification of weakly-salted water solutions (waste waters, ships drainage tanks, showers and laundries) of the Beloyarsk NPP are presented. Sorbents source characteristics are determined. 4 refs., 2 figs., 3 tabs

  8. Application of engineered sorbent barriers Summary of Laboratory Data for FY 1988

    Energy Technology Data Exchange (ETDEWEB)

    Freeman, H.D.; Jones, E.O.

    1989-09-01

    Laboratory studies were conducted in FY 1988 Pacific Northwest Laboratory to determine the effect of contact time, pH, solution to solid ratio, and particle size on the performance of a number of materials in adsorbing radioactive cobalt, strontium, and cesium. The laboratory studies were conducted to provide background information useful in designing an engineered sorbent barrier, which restricts the migration of radionuclides from low-level waste sites. Understanding how the variables affect the adsorption of ions on the sorbent materials is the key to estimating the performance of sorbent barriers under a variety of conditions. The scope of the studies was limited to three radionuclides and four sorbent materials, but the general approach can be used to evaluate other radionuclides and conditions. The sorbent materials evaluated in this study included clinoptilolite, activated carbon, bentonite clay, and Savannah River soil. The clinoptilolite and activated carbon were identified in previous studies as the most cost-effective materials for sorption of the three radionuclides under consideration. The bentonite clay was evaluated as a component of the barrier that could be used to modify the permeability of the barrier system. The Savannah River soil was used to represent soil from a humid site. 3 refs., 14 figs., 1 tab.

  9. Improved CO_2 adsorption capacity and cyclic stability of CaO sorbents incorporated with MgO

    International Nuclear Information System (INIS)

    Farah Diana Mohd Daud; Kumaravel Vignesh; Srimala Sreekantan; Abdul Rahman Mohamed

    2016-01-01

    Calcium oxide (CaO) sorbents incorporated with magnesium oxide (MgO) were synthesized using a co-precipitation route. The sorbents were prepared with different MgO concentrations (from 5 wt% to 30 wt%). The as-prepared sorbents were characterized using X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), energy dispersive X-ray spectroscopy (EDX) and BET surface area analysis techniques. The sintering effect of CaO sorbents was decreased after the incorporation of MgO. The sorbents with 5 wt% and 10 wt% of MgO retained their CO_2 adsorption capacity over multiple cycles. Most importantly, CaO with 10 wt% MgO showed constant CO_2 adsorption capacity over 30 carbonation cycles. The results revealed that CaO with 10 wt% MgO is sufficient to produce sorbents with high surface area, good structural stability and enhanced CO_2 adsorption capacity. (authors)

  10. Ionic liquids: solvents and sorbents in sample preparation.

    Science.gov (United States)

    Clark, Kevin D; Emaus, Miranda N; Varona, Marcelino; Bowers, Ashley N; Anderson, Jared L

    2018-01-01

    The applications of ionic liquids (ILs) and IL-derived sorbents are rapidly expanding. By careful selection of the cation and anion components, the physicochemical properties of ILs can be altered to meet the requirements of specific applications. Reports of IL solvents possessing high selectivity for specific analytes are numerous and continue to motivate the development of new IL-based sample preparation methods that are faster, more selective, and environmentally benign compared to conventional organic solvents. The advantages of ILs have also been exploited in solid/polymer formats in which ordinarily nonspecific sorbents are functionalized with IL moieties in order to impart selectivity for an analyte or analyte class. Furthermore, new ILs that incorporate a paramagnetic component into the IL structure, known as magnetic ionic liquids (MILs), have emerged as useful solvents for bioanalytical applications. In this rapidly changing field, this Review focuses on the applications of ILs and IL-based sorbents in sample preparation with a special emphasis on liquid phase extraction techniques using ILs and MILs, IL-based solid-phase extraction, ILs in mass spectrometry, and biological applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Biologically produced sulfur

    NARCIS (Netherlands)

    Kleinjan, W.E.; Keizer, de A.; Janssen, A.J.H.

    2003-01-01

    Sulfur compound oxidizing bacteria produce sulfur as an intermediate in the oxidation of hydrogen sulfide to sulfate. Sulfur produced by these microorganisms can be stored in sulfur globules, located either inside or outside the cell. Excreted sulfur globules are colloidal particles which are

  12. Methods and sorbents for utilizing a hot-side electrostatic precipitator for removal of mercury from combustion gases

    Science.gov (United States)

    Nelson, Sidney [Hudson, OH

    2011-02-15

    Methods are provided for reducing emission of mercury from a gas stream by treating the gas with carbonaceous mercury sorbent particles to reduce the mercury content of the gas; collecting the carbonaceous mercury sorbent particles on collection plates of a hot-side ESP; periodically rapping the collection plates to release a substantial portion of the collected carbonaceous mercury sorbent particles into hoppers; and periodically emptying the hoppers, wherein such rapping and emptying are done at rates such that less than 70% of mercury adsorbed onto the mercury sorbent desorbs from the collected mercury sorbent into the gas stream.

  13. Reactivity improvement of Ca(OH)2 sorbent using diatomaceous earth (DE) from Aceh Province

    Science.gov (United States)

    Mariana, M.; Mahidin, M.; Mulana, F.; Agam, T.; Hafdiansyah, F.

    2018-04-01

    In this study, the diatomaceous earth (DE) from Aceh Province was used to increase the reactivity of Ca(OH)2sorbent. The high silica (SiO2) content of about 97% in the diatomaceous earth allows the increasing reactivity of Ca(OH)2sorbent by forming calcium silicate hydrate (CSH). The CSH improved the porosity characteristic of the sorbent. The improvement process was performed by mixing Ca(OH)2sorbent, diatomaceous earth and water in a beaker glass at the Ca(OH)2/DE weight ratio of 1:10 for 2 hand then dried at 120 °C for 24 h. The dried sorbent was calcined at 500 °C and 800 °C for 2 h. The activated sorbent was characterized using Scanning Electron Microscopy (SEM) for the morphological properties; X- Ray Diffraction (XRD) for the materials characteristics. The adsorption capacity of thesorbent was tested by methylene blue adsorption. The results showed that the Ca(OH)2/DEsorbent had a higher porosity than the Ca(OH)2 adsorbent.The results also showed that Ca(OH)2/DE which was calcined at higher temperature of 800 °C had a higher adsorption capacity compared to Ca(OH)2/DE which was calcined at lower temperature of 500 °C.

  14. Synergy effect of naphthenic acid corrosion and sulfur corrosion in crude oil distillation unit

    Energy Technology Data Exchange (ETDEWEB)

    Huang, B.S., E-mail: yinwenfeng2010@163.com [College of Materials Science and Engineering, Southwest Petroleum University, Sichuan, Chengdu, 610500 (China); Yin, W.F. [College of Mechatronic Engineering, Southwest Petroleum University, Sichuan, Chengdu, 610500 (China); Sang, D.H. [Sheng Li Construction Group International Engineering Department, Shandong, Dongying, 257000 (China); Jiang, Z.Y. [College of Materials Science and Engineering, Southwest Petroleum University, Sichuan, Chengdu, 610500 (China)

    2012-10-15

    Highlights: Black-Right-Pointing-Pointer The corrosion of a carbon-manganese steel and a stainless steel in sulfur and/or naphthenic acid media was investigated. Black-Right-Pointing-Pointer The corrosion rate of the carbon-manganese steel increased with the increase of the acid value and sulfur content. Black-Right-Pointing-Pointer The critical values of the concentration of sulfur and acid for corrosion rate of the stainless steel were ascertained respectively. Black-Right-Pointing-Pointer The stainless steel is superior to the carbon-manganese steel in corrosion resistance because of the presence of stable Cr{sub 5}S{sub 8} phases. - Abstract: The synergy effect of naphthenic acid corrosion and sulfur corrosion at high temperature in crude oil distillation unit was studied using Q235 carbon-manganese steel and 316 stainless steel. The corrosion of Q235 and 316 in corrosion media containing sulfur and/or naphthenic acid at 280 Degree-Sign C was investigated by weight loss, scanning electron microscope (SEM), EDS and X-ray diffractometer (XRD) analysis. The results showed that in corrosion media containing only sulfur, the corrosion rate of Q235 and 316 first increased and then decreased with the increase of sulfur content. In corrosion media containing naphthenic acid and sulfur, with the variations of acid value or sulfur content, the synergy effect of naphthenic acid corrosion and sulfur corrosion has a great influence on the corrosion rate of Q235 and 316. It was indicated that the sulfur accelerated naphthenic acid corrosion below a certain sulfur content but prevented naphthenic acid corrosion above that. The corrosion products on two steels after exposure to corrosion media were investigated. The stable Cr{sub 5}S{sub 8} phases detected in the corrosion products film of 316 were considered as the reason why 316 has greater corrosion resistance to that of Q235.

  15. Effect of Iron Oxides (Ordinary and Nano and Municipal Solid Waste Compost (MSWC Coated Sulfur on Wheat (Triticum aestivum L. Plant Iron Concentration and Growth

    Directory of Open Access Journals (Sweden)

    S Mazaherinia

    2011-02-01

    Full Text Available Abstract A greenhouse study was conducted to compare the effects of ordinary iron oxide (0.02-0.06 mm and nano iron oxide (25-250 nm and five levels of both iron oxides (0, 0.05, 0.1, 0.5, and 1.0 %w/w and two levels of sulfurous granular compost (MSW (0 and 2% w/w on plant height, spike length, grain weight per spike, total plant dry matter weight and thousands grain weight of wheat. The experimental factors were combined in factorial arrangement in a completely randomized design with 3 replications. Results showed that nano iron oxide was superior over ordinary iron oxide in all parameters studied. Fe concentration, spike length, plant height, grain weight per spike, total plant dry weight and thousands grain weight showed increasing trend per increase in both of iron oxides levels. Also, all parameters studied in sulfurous granular compost (MSW treatment were superior over granular compost without sulfurous (MSW. This increase in all parameters were significantly higher when urban solid waste compost coated with sulfur coupled with nano iron oxide compared to urban sulfurous granular compost (MSW along with ordinary iron oxide. Keywords: Sulfurous granular compost (MSW, Nano and ordinary iron oxides, Wheat

  16. Arsenic removal from aqueous solutions by sorption onto zirconium- and titanium-modified sorbents

    Directory of Open Access Journals (Sweden)

    Ignjatović Ljubiša

    2011-01-01

    Full Text Available Arsenic reduction in drinking water can include treatment by adsorption, switching to alternative water sources, or blending with water that has a lower arsenic concentration. Commercial sorbents MTM, Greensand and BIRM (Clack Corporation were modified with zirconium and titanium after activation. The modifications were performed with titanium tetrachloride and zirconium tetrachloride. The modified sorbents were dried at different temperatures. The sorption of arsenate and arsenite dissolved in drinking water (200μg L-1 onto the sorbents were tested using a batch procedure. After removal of the sorbent, the concentration of arsenic was determined by HG-AAS. Zirconium-modified BIRM showed the best performance for the removal of both arsenite and arsenate. Modification of the greensand did not affect arsenic sorption ability. Zirconium-modified BIRM diminished the concentration of total As to below 5 μg L-1.

  17. Effect of sulfur content in a sulfur-activated carbon composite on the electrochemical properties of a lithium/sulfur battery

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin-Woo; Kim, Changhyeon; Ryu, Ho-Suk; Cho, Gyu-Bong; Cho, Kwon-Koo; Kim, Ki-Won [School of Materials Science and Engineering, Gyeongsang National University, Jinju (Korea, Republic of); Ahn, Jou-Hyeon [Department of Chemical & Biological Engineering, Gyeongsang National University, Jinju (Korea, Republic of); Wang, Guoxiu [School of Chemistry and Forensic Science, University of Technology Sydney, Sydney, NSW 2007 (Australia); Ahn, Jae-Pyeung [Advanced Analysis Center, Research Planning & Coordination Division, KIST, Seoul (Korea, Republic of); Ahn, Hyo-Jun, E-mail: ahj@gnu.ac.kr [School of Materials Science and Engineering, Gyeongsang National University, Jinju (Korea, Republic of)

    2015-09-15

    Highlights: • The content of sulfur in activated carbon was controlled by solution process. • The sulfur electrode with low sulfur content shows the best performance. • The Li/S battery has capacity of 1360 mAh/g at 1 C and 702 mAh/g at 10 C. - Abstract: The content of sulfur in sulfur/activated carbon composite is controlled from 32.37 wt.% to 55.33 wt.% by a one-step solution-based process. When the sulfur content is limited to 41.21 wt.%, it can be loaded into the pores of an activated carbon matrix in a highly dispersed state. On the contrary, when the sulfur content is 55.33 wt.%, crystalline sulfur can be detected on the surface of the activated carbon matrix. The best electrochemical performance can be obtained for a sulfur electrode with the lowest sulfur content. The sulfur/activated carbon composite with 32.37 wt.% sulfur afforded the highest first discharge capacity of 1360 mAh g{sup −1} at 1 C rate and a large reversible capacity of 702 mAh g{sup −1} at 10 C (16.75 A/g)

  18. Removal of H/sub 2/S from hot gas in the presence of Cu-containing sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Kyotani, T.; Kawashima, H.; Tomita, A.; Palmer, A.; Furimsky, E.

    1989-01-01

    Three solids containing Cu oxides were tested as sorbents for H/sub 2/S removal from hot gas at 600 degrees C. The formation of a surface layer of sulphides on pellet exterior affected Cu utilization for the sorbent prepared from Cu oxides alone. This improved for the sorbent prepared by impregnation of zeolite with Cu oxides, although complete utilization of Cu was not achieved. The combination of Cu oxides with SiO/sub 2/ gave the most efficient sorbent. Oxidation of H/sub 2/S to SO/sub 2/ on admission of hot gas to the fixed bed was a common observation for all sorbents. The addition of steam to hot gas suppressed the SO/sub 2/ formation. 9 refs., 6 figs., 4 tabs.

  19. Data summary report for M.W. Kellogg Z-sorb sorbent tests. CRADA 92-008 Final report

    Energy Technology Data Exchange (ETDEWEB)

    Everett, C E; Monaco, S J

    1994-05-01

    A series of tests were undertaken from August 6, 1992 through July 6, 1993 at METC`s High Pressure Bench-Scale Hot Gas Desulfurization Unit to support a Cooperative Research and Development Agreement (CRADA) between METC`s Sorbent Development Cluster and M.W. Kellogg. The M.W. Kellogg Company is currently developing a commercial offering of a hot gas clean-up system to be used in Integrated Gasification Combined Cycle (IGCC) systems. The intent of the CRADA agreement was to identify a suitable zinc-based desulfurization sorbent for the Sierra Pacific Power Company Clean Coal Technology Project, to identify optimum operating conditions for the sorbent, and to estimate potential sorbent loss per year. This report presents results pertaining to Phillips Petroleum`s Z-Sorb III sorbent.

  20. Performance Evaluation of Engineered Structured Sorbents for Atmosphere Revitalization Systems On Board Crewed Space Vehicles and Habitats

    Science.gov (United States)

    Howard, David F.; Perry, Jay L.; Knox, James C.; Junaedi, Christian; Roychoudhury, Subir

    2011-01-01

    Engineered structured (ES) sorbents are being developed to meet the technical challenges of future crewed space exploration missions. ES sorbents offer the inherent performance and safety attributes of zeolite and other physical adsorbents but with greater structural integrity and process control to improve durability and efficiency over packed beds. ES sorbent techniques that are explored include thermally linked and pressure-swing adsorption beds for water-save dehumidification and sorbent-coated metal meshes for residual drying, trace contaminant control, and carbon dioxide control. Results from sub-scale performance evaluations of a thermally linked pressure-swing adsorbent bed and an integrated sub-scale ES sorbent system are discussed.

  1. Performance of a novel synthetic Ca-based solid sorbent suitable for desulfurizing flue gases in a fluidized bed

    Energy Technology Data Exchange (ETDEWEB)

    Pacciani, R.; Muller, C.R.; Davidson, J.F.; Dennis, J.S.; Hayhurst, A.N. [University of Cambridge, Cambridge (United Kingdom). Dept. of Chemical Engineering & Biotechnology

    2009-08-05

    The extent and mechanism of sulfation and carbonation of limestone, dolomite, and chalk, were compared with a novel, synthetic sorbent (85 wt % CaO and 15 wt % Ca{sub 12}A{sub l14}O{sub 33}), by means of experiments undertaken in a small, electrically heated fluidized bed. The sorbent particles were used either (I) untreated, sieved to two particle sizes and reacted with two different concentrations of SO{sub 2}, or (ii) after being cycled 20 times between carbonation, in 15 vol % CO{sub 2} in N2, and calcination, in pure N2, at 750 degrees C. The uptake of untreated limestone and dolomite was generally low (<0.2 g(SO{sub 2})/g(sorbent)), confirming previous results, However, the untreated chalk and the synthetic sorbent were found to be substantially more reactive with SO{sub 2}, and their final uptake was significantly higher (>0.5 g(SO{sub 2})/g(sorbent)) and essentially independent of the particle size. Here, comparisons are made on the basis of the sorbents in the calcined state. The capacities for the uptake of SO{sub 2}, on a basis of unit mass of calcined sorbent, were comparable for the chalk and the synthetic sorbent. However, previous work has demonstrated the ability of the synthetic sorbent to retain its capacity for CO{sub 2} over many cycles of carbonation and calcination: much more so than natural sorbents such as chalk and limestone. Accordingly, the advantage of the synthetic sorbent is that it could be used to remove CO{sub 2} from flue gases and, at the end of its life, to remove SO{sub 2} on a once-through basis.

  2. EVALUATION OF SOLID SORBENTS AS A RETROFIT TECHNOLOGY FOR CO2 CAPTURE FROM COAL-FIRED POWER PLANTS

    Energy Technology Data Exchange (ETDEWEB)

    Holly Krutka; Sharon Sjostrom

    2011-07-31

    Through a U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) funded cooperative agreement DE-NT0005649, ADA Environmental Solutions (ADA) has begun evaluating the use of solid sorbents for CO{sub 2} capture. The project objective was to address the viability and accelerate development of a solid-based CO{sub 2} capture technology. To meet this objective, initial evaluations of sorbents and the process/equipment were completed. First the sorbents were evaluated using a temperature swing adsorption process at the laboratory scale in a fixed-bed apparatus. A slipstream reactor designed to treat flue gas produced by coal-fired generation of nominally 1 kWe was designed and constructed, which was used to evaluate the most promising materials on a more meaningful scale using actual flue gas. In a concurrent effort, commercial-scale processes and equipment options were also evaluated for their applicability to sorbent-based CO{sub 2} capture. A cost analysis was completed that can be used to direct future technology development efforts. ADA completed an extensive sorbent screening program funded primarily through this project, DOE NETL cooperative agreement DE-NT0005649, with support from the Electric Power Research Institute (EPRI) and other industry participants. Laboratory screening tests were completed on simulated and actual flue gas using simulated flue gas and an automated fixed bed system. The following types and quantities of sorbents were evaluated: 87 supported amines; 31 carbon based materials; 6 zeolites; 7 supported carbonates (evaluated under separate funding); and 10 hydrotalcites. Sorbent evaluations were conducted to characterize materials and down-select promising candidates for further testing at the slipstream scale. More than half of the materials evaluated during this program were supported amines. Based on the laboratory screening four supported amine sorbents were selected for evaluation at the 1 kW scale at two different

  3. AIR SEPARATION BY PRESSURE SWING ADSORPTION USING SUPERIOR ADSORBENTS; FINAL

    International Nuclear Information System (INIS)

    Ralph T Yang

    2001-01-01

    Li-X zeolite (Si/Al= 1.0) is currently the best sorbent for use in the separation of air by adsorption processes. In particular, pressure swing adsorption (PSA) using zeolite sorbents is being increasingly used for air separation. Silver is also known to strongly affect the adsorptive properties of zeolites; and it is known that thermal vacuum dehydration of silver zeolites leads to the formation of silver clusters within the zeolite. In this work we have synthesized type X zeolites containing Ag and also varying mixtures of Li and Ag. In this project, we developed the Ag-containing zeolite as the best sorbent for air separation. We have also studied Co-ligand compounds as oxygen-selective sorbents. Syntheses, structural characterization and adsorption properties have been performed on all sorbents. The results are described in detail in 5 chapters

  4. Sulfur-Kβ /sub emission studies on sulfur-bearing heterocycles

    International Nuclear Information System (INIS)

    Phillips, D.R.; Andermann, G.G.; Fujiwara, F.

    1986-01-01

    Sulfur-K/β /sub x-ray fluorescence spectroscopy (XFS) has been used to study the electronic structure and bonding in sulfur-bearing heterocycles. XFS not only has the capability of experimentally measuring valence electron energies in molecular species, but can also provide intensity data which can help define the nature of the molecular orbitals defined by the electrons. This report discusses the feasibility of using XFS as an analytical tool for the determination of total and specific sulfur heterocycle content in samples. A variety of compounds were studied. These include thiophene, thiophene derivatives, tetranydrothiophene, several more complex saturated and unsaturated sulfur heterocycles, and heterocycles containing both sulfur and nitrogen. The sulfur-K/β /sub spectra were obtained using a double crystal spectrometer which provided an instrumental resolution of about 0.7 eV

  5. Adsorption of Polycyclic Aromatic Hydrocarbons (PAHS from Aqueous Solutions on Different Sorbents

    Directory of Open Access Journals (Sweden)

    Smol Marzena

    2014-12-01

    Full Text Available This paper presents the results of the possibility and effectiveness of PAHs removal from a model aqueous solution, during the sorption on the selected sorbents. Six PAHs (naphthalene, acenaphthylene, acenaphthene, fluorene, phenanthrene, anthracene listed by EPA for the analysis in the environmental samples were determined. Model aqueous solution was prepared with RESTEK 610 mix PAHs standard. After the sorption process, decrease in the concentration of individual hydrocarbons was observed. The removal percentage was dependent on the type of sorbent (quartz sand, mineral sorbent, activated carbon. The highest efficiency (98.1% was observed for activated carbon.. The results shows that the sorption processes can be used in aqueous solutions treatment procedures.

  6. Graphene-wrapped sulfur nanospheres with ultra-high sulfur loading for high energy density lithium–sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Ya; Guo, Jinxin; Zhang, Jun, E-mail: zhangjun@zjnu.cn; Su, Qingmei; Du, Gaohui, E-mail: gaohuidu@zjnu.edu.cn

    2015-01-01

    Graphical abstract: - Highlights: • A graphene-wrapped sulfur nanospheres composite with 91 wt% S is prepared. • It shows highly improved electrochemical performance as cathode for Li–S cell. • The PVP coating and conductive graphene minimize polysulfides dissolution. • The flexible coatings with void space accommodate the volume expansion of sulfur. - Abstract: Lithium–sulfur (Li–S) battery with high theoretical energy density is one of the most promising energy storage systems for electric vehicles and intermittent renewable energy. However, due to the poor conductivity of the active material, considerable weight of the electrode is occupied by the conductive additives. Here we report a graphene-wrapped sulfur nanospheres composite (S-nanosphere@G) with sulfur content up to 91 wt% as the high energy density cathode material for Li–S battery. The sulfur nanospheres with diameter of 400–500 nm are synthesized through a solution-based approach with the existence of polyvinylpyrrolidone (PVP). Then the sulfur nanospheres are uniformly wrapped by conductive graphene sheets through the electrostatic interaction between graphene oxide and PVP, followed by reducing of graphene oxide with hydrazine. The design of graphene wrapped sulfur nanoarchitecture provides flexible conductive graphene coating with void space to accommodate the volume expansion of sulfur and to minimize polysulfide dissolution. As a result, the S-nanosphere@G nanocomposite with 91 wt% sulfur shows a reversible initial capacity of 970 mA h g{sup −1} and an average columbic efficiency > 96% over 100 cycles at a rate of 0.2 C. Taking the total mass of electrode into account, the S-nanosphere@G composite is a promising cathode material for high energy density Li–S batteries.

  7. Multiple-heteroatom-containing sulfur compounds in a high sulfur coal

    International Nuclear Information System (INIS)

    Winans, R.E.; Neill, P.H.

    1990-01-01

    Flash vacuum pyrolysis of a high sulfur coal has been combined with high resolution mass spectrometry yielding information on aromatic sulfur compounds containing an additional heteroatom. Sulfur emission from coal utilization is a critical problem and in order to devise efficient methods for removing organic sulfur, it is important to know what types of molecules contain sulfur. A high sulfur Illinois No. 6 bituminous coal (Argonne Premium Coal Sample No. 3) was pyrolyzed on a platinum grid using a quartz probe inserted into a modified all glass heated inlet system and the products characterized by high resolution mass spectrometry (HRMS). A significant number of products were observed which contained both sulfur and an additional heteroatom. In some cases two additional heteroatoms were observed. These results are compared to those found in coal extracts and liquefaction products

  8. KINETICS OF DIRECT OXIDATION OF H2S IN COAL GAS TO ELEMENTAL SULFUR; F

    International Nuclear Information System (INIS)

    K.C. Kwon

    2002-01-01

    Removal of hydrogen sulfide (H(sub 2)S) from coal gasifier gas and sulfur recovery are key steps in the development of Department of Energy's (DOE's) advanced Vision 21 plants that employ coal and natural gas and produce electric power and clean transportation fuels. These Vision 21 plants will require highly clean coal gas with H(sub 2)S below 1 ppm and negligible amounts of trace contaminants such as hydrogen chloride, ammonia, alkali, heavy metals, and particulate. The conventional method of sulfur removal and recovery employing amine, Claus, and tail-gas treatment is very expensive. A second generation approach developed under DOE's sponsorship employs hot-gas desulfurization (HGD) using regenerable metal oxide sorbents followed by Direct Sulfur Recovery Process (DSRP). However, this process sequence does not remove trace contaminants and is targeted primarily towards the development of advanced integrated gasification combined cycle (IGCC) plants that produce electricity (not both electricity and transportation fuels). There is an immediate as well as long-term need for the development of cleanup processes that produce highly clean coal gas for next generation Vision 21 plants. To this end, a novel process is now under development at Research Triangle Institute (RTI) in which the H(sub 2)S in coal gas is directly oxidized to elemental sulfur over a selective catalyst. Such a process is ideally suited for coal gas from commercial gasifiers with a quench system to remove essentially all the trace contaminants except H(sub 2)S. This direct oxidation process has the potential to produce a super clean coal gas more economically than both conventional amine-based processes and HGD/DSRP. The objective of this research is to support the near- and long-term DOE efforts to commercialize this direct oxidation technology. Specifically, we aim to: Measure the kinetics of direct oxidation of H(sub 2)S to elemental sulfur over selective catalysts in the presence of major

  9. Insight into the loading temperature of sulfur on sulfur/carbon cathode in lithium-sulfur batteries

    International Nuclear Information System (INIS)

    Ye, Huan; Yin, Ya-Xia; Guo, Yu-Guo

    2015-01-01

    Highlights: • A cost-effective chemical activation method to prepare porous carbon nanospheres. • Carbon nanospheres with bimodal microporous structure show high specific area and large micropore volume. • The S/C composite cathodes with in-situformed S−C bond exhibit high sulfur activity with a reversible capacity of 1000 mA h g −1 . • S−C bond enables well confinement on sulfur and polysulfides. - Abstract: Lithium–sulfur batteries are highly desired because of their characteristics such as high energy density. However, the applications of Li-S batteries are limited because they exist dissolution of polysulfides into electrolytes. This study reports the preparation of sulfur cathodes by using bimodal microporous (0.5 nm and 0.8 nm to 2.0 nm) carbon spheres with high specific area (1992 m 2 g −1 ) and large micropore volume (1.2 g cm −1 ), as well as the encapsulation of polysulfides via formation of carbon–sulfur bonds in a sealed vacuum glass tube at high temperature. Given that sulfur and polysulfides are well confined by the S−C bond, the shuttle effect is effectively suppressed. The prepared S/C cathodes with a sulfur loading of up to 75% demonstrate high sulfur activity with reversible capacity of 1000 mA h g −1 at the current density of 0.1 A g −1 and good cycling stability (667 mA h g −1 after 100 cycles).

  10. Effect of precursor and preparation method on manganese based activated carbon sorbents for removing H2S from hot coal gas.

    Science.gov (United States)

    Wang, Jiancheng; Qiu, Biao; Han, Lina; Feng, Gang; Hu, Yongfeng; Chang, Liping; Bao, Weiren

    2012-04-30

    Activated carbon (AC) supported manganese oxide sorbents were prepared by the supercritical water impregnation (SCWI) using two different precursor of Mn(NO(3))(2) (SCW(N)) and Mn(Ac)(2)·4H(2)O (SCW(A)). Their capacities of removing H(2)S from coal gas were evaluated and compared to the sorbents prepared by the pore volume impregnation (PVI) method. The structure and composition of different sorbents were characterized by XRD, SEM, TEM, XPS and XANES techniques. It is found that the precursor of active component plays the crucial role and SCW(N) sorbents show much better sulfidation performance than the SCW(A) sorbents. This is because the Mn(3)O(4) active phase of the SCW(N) sorbents are well dispersed on the AC support, while the Mn(2)SiO(4)-like species in the SCW(A) sorbent can be formed and seriously aggregated. The SCW(N) sorbents with 2.80% and 5.60% manganese are favorable for the sulfidation reaction, since the Mn species are better dispersed on the SCW(N) sorbents than those on the PV(N) sorbents and results in the better sulfidation performance of the SCW(N) sorbents. As the Mn content increases to 11.20%, the metal oxide particles on AC supports aggregate seriously, which leads to poorer sulfidation performance of the SCW(N)11.20% sorbents than that of the PV(N)11.20% sorbents. Copyright © 2012 Elsevier B.V. All rights reserved.

  11. Research on using Mineral Sorbents for A Sorption Process in the Environment Contaminated with Petroleum Substances

    Directory of Open Access Journals (Sweden)

    Pijarowski Piotr Marek

    2014-06-01

    Full Text Available A research on diatomite sorbents was carried out to investigate their ability to remove hazardous substances from oil spillages. We used two types of sorbents available on the market with differences in material density and particles size of composition. As sorbents we used Ekoterm oil and unleaded petrol 95 coming from refinery PKN Orlen S.A. Two types of sorbents with similar chemical composition but different granulometric composition were used. They are marked as D1 and C1 samples. The fastest absorbent was C1, but D1 sample was the most absorptive.

  12. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, or ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. This quarter, five cycle thermogravimetric tests were conducted at the Louisiana State University (LSU) with sodium bicarbonate Grade 3 (SBC(number s ign)3) which showed that carbonation activity declined slightly over 5 cycles following severe calcination conditions of 200 C in pure CO(sub 2). Three different sets of calcination conditions were tested. Initial carbonation activity (as measured by extent of reaction in the first 25 minutes) was greatest subsequent to calcination at 120 C in He, slightly less subsequent to calcination in 80% CO(sub 2)/20% H(sub 2)O, and lowest subsequent to calcination in pure CO(sub 2) at 200 C. Differences in the extent of reaction after 150 minutes of carbonation, subsequent to calcination under the same conditions followed the same trend but were less significant. The differences between fractional carbonation under the three calcination conditions declined with increasing cycles. A preliminary fixed bed reactor test was also conducted at LSU. Following calcination, the sorbent removed approximately 19% of the CO(sub 2) in the simulated flue gas. CO(sub 2) evolved during subsequent calcination was consistent with an extent of carbonation of approximately 49%. Following successful testing of SBC(number s ign)3 sorbent at RTI reported in the last quarter, a two cycle fluidized bed reactor test was conducted with trona as the sorbent precursor, which was calcined to sodium carbonate. In the first carbonation cycle, CO

  13. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO{sub 2} as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbent being used in this project is sodium carbonate which is converted to sodium bicarbonate, or ''baking soda,'' through reaction with carbon dioxide and water vapor. Sodium bicarbonate is regenerated to sodium carbonate when heated, producing a nearly pure CO{sub 2} stream after condensation of water vapor. This quarter, five cycle thermogravimetric tests were conducted at the Louisiana State University (LSU) with sodium bicarbonate Grade 3 (SBC{number_sign}3) which showed that carbonation activity declined slightly over 5 cycles following severe calcination conditions of 200 C in pure CO{sub 2}. Three different sets of calcination conditions were tested. Initial carbonation activity (as measured by extent of reaction in the first 25 minutes) was greatest subsequent to calcination at 120 C in He, slightly less subsequent to calcination in 80% CO{sub 2}/20% H{sub 2}O, and lowest subsequent to calcination in pure CO{sub 2} at 200 C. Differences in the extent of reaction after 150 minutes of carbonation, subsequent to calcination under the same conditions followed the same trend but were less significant. The differences between fractional carbonation under the three calcination conditions declined with increasing cycles. A preliminary fixed bed reactor test was also conducted at LSU. Following calcination, the sorbent removed approximately 19% of the CO{sub 2} in the simulated flue gas. CO{sub 2} evolved during subsequent calcination was consistent with an extent of carbonation of approximately 49%. Following successful testing of SBC{number_sign}3 sorbent at RTI reported in the last quarter, a two cycle fluidized bed reactor test was conducted with trona as the sorbent precursor, which was calcined to sodium carbonate. In the first

  14. Improved method for minimizing sulfur loss in analysis of particulate organic sulfur.

    Science.gov (United States)

    Park, Ki-Tae; Lee, Kitack; Shin, Kyoungsoon; Jeong, Hae Jin; Kim, Kwang Young

    2014-02-04

    The global sulfur cycle depends primarily on the metabolism of marine microorganisms, which release sulfur gas into the atmosphere and thus affect the redistribution of sulfur globally as well as the earth's climate system. To better quantify sulfur release from the ocean, analysis of the production and distribution of organic sulfur in the ocean is necessary. This report describes a wet-based method for accurate analysis of particulate organic sulfur (POS) in the marine environment. The proposed method overcomes the considerable loss of sulfur (up to 80%) that occurs during analysis using conventional methods involving drying. Use of the wet-based POS extraction procedure in conjunction with a sensitive sulfur analyzer enabled accurate measurements of cellular POS. Data obtained using this method will enable accurate assessment of how rapidly sulfur can transfer among pools. Such information will improve understanding of the role of POS in the oceanic sulfur cycle.

  15. Calcium looping technology using improved stability nanostructured sorbent for cyclic CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Luo, Cong; Zheng, Ying; Ding, Ning; Zheng, Chu-guang [Huazhong Univ. of Science and Technology, Wuhan (China). State Key Lab. of Coal Combustion

    2013-07-01

    One of the post-combustion CO{sub 2} capture technologies that have sufficiently been proved to be the best candidates for practical large scale post-combustion application is the calcium looping cycle. However, the CO{sub 2} capture capacity of a calcium-based sorbent derived from natural limestone decays through long-term cyclic utilization; thus, the development of novel sorbents to achieve a high CO{sub 2} capture capacity is an critical challenge for the calcium looping cycle technology. In this paper, we report the preparation and character of a new calcium-based sorbent produced via the combustion of a dry gel. The results show that the novel calcium-based sorbent has a much higher residual carbonation conversion as well as a better performance of anti-sintering when compared with the calcium-based sorbent derived from commercial micrometer grade CaCO{sub 3} and nanometer grade CaCO{sub 3}. It is reasonable to propose that the different final carbonation performances are induced by their different pore structures and BET surface areas rather than by different particle sizes. Compared with the commercial nano CaO, the morphology of the new sorbent shows a more rough porous appearance with hollow nanostructure. During carbonation, CO{sub 2} diffused more easily through the hollow structure than through a solid structure to reach the unreacted CaO. Besides, there is less chance for the hollow nanostructured particles to be merged together during the high temperature reactions.

  16. Release of iodine radionuclides from gas media in a system of selective block sorbents

    International Nuclear Information System (INIS)

    Moskvin, L.N.; Miroshnikov, V.S.; Mel'nikov, V.A.; Chetverikov, V.V.

    1979-01-01

    A scheme of extracting iodine radionuclides from gas flows in a system of selective sorbents has been developed. The method provides separation of three forms of iodine: the aerosol component, the elementary iodine and organic-iodine compounds. Aerosols are trapped by a mechanical filter made of porous polytetrafluoroethylene with pores of no more than 1 μm. Silver-based sorbents for the elementary iodine are made by sintering the granular polytetrafluoroethylene (the size of granules is 0.1-0.5 mm) with of finely dispersed solver (5% mass). Organic iodine compounds are extracted by a silica sorbent impregnated with silver nitrate. The efficiency of sorbents was tested in gas flows with a known content of 131 I in the form of elementary iodine and methyl iodide. The results of experiments show that the efficiency of sorption of elementary iodine by a metallic-silver sorbent and of methyl iodide by a SiO 2 /AgNO 3 sorbent constitutes no less than 99% at a flow rate of up to 200 l/h. The iodine has been extracted at a flow rate of 100 l/h during 100 hours and for that time the efficiency of the iodine sorbtion has not changed. The suggested variant of extracting iodine radionuclides from gaseous media can be used both for fast control of iodine content in gas blowoffs and for researches aimed at studying the distribution of iodine forms in steam-and-gas media depending on nuclear plant operating conditions

  17. Sorption of Aromatic Compounds with Copolymer Sorbent Materials Containing β-Cyclodextrin

    OpenAIRE

    Wilson, Lee D.; Mohamed, Mohamed H.; Berhaut, Christopher L.

    2011-01-01

    Urethane copolymer sorbent materials that incorporate β-cyclodextrin (CD) have been prepared and their sorption properties with chlorinated aromatic compounds (i.e., pentachlorophenol, 2,4-dichlorophenol and 2,4-dichlorophenoxy acetic acid) have been evaluated. The sorption properties of granular activated carbon (GAC) were similarly compared in aqueous solution at variable pH conditions. The sorbents displayed variable BET surface areas as follows: MDI-X copolymers (< 101 m2/g), CDI-X cop...

  18. Warm Cleanup of Coal-Derived Syngas: Multicontaminant Removal Process Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Spies, Kurt A.; Rainbolt, James E.; Li, Xiaohong S.; Braunberger, Beau; Li, Liyu; King, David L.; Dagle, Robert A.

    2017-02-15

    Warm cleanup of coal- or biomass-derived syngas requires sorbent and catalytic beds to protect downstream processes and catalysts from fouling. Sulfur is particularly harmful because even parts-per-million amounts are sufficient to poison downstream synthesis catalysts. Zinc oxide (ZnO) is a conventional sorbent for sulfur removal; however, its operational performance using real gasifier-derived syngas and in an integrated warm cleanup process is not well reported. In this paper, we report the optimal temperature for bulk desulfurization to be 450oC, while removal of sulfur to parts-per-billion levels requires a lower temperature of approximately 350oC. Under these conditions, we found that sulfur in the form of both hydrogen sulfide and carbonyl sulfide could be absorbed equally well using ZnO. For long-term operation, sorbent regeneration is desirable to minimize process costs. Over the course of five sulfidation and regeneration cycles, a ZnO bed lost about a third of its initial sulfur capacity, however sorbent capacity stabilized. Here, we also demonstrate, at the bench-scale, a process and materials used for warm cleanup of coal-derived syngas using five operations: 1) Na2CO3 for HCl removal, 2) regenerable ZnO beds for bulk sulfur removal, 3) a second ZnO bed for trace sulfur removal, 4) a Ni-Cu/C sorbent for multi-contaminant inorganic removal, and 5) a Ir-Ni/MgAl2O4 catalyst employed for ammonia decomposition and tar and light hydrocarbon steam reforming. Syngas cleanup was demonstrated through successful long-term performance of a poison-sensitive, Cu-based, water-gas-shift catalyst placed downstream of the cleanup process train. The tar reformer is an important and necessary operation with this particular gasification system; its inclusion was the difference between deactivating the water-gas catalyst with carbon deposition and successful 100-hour testing using 1 LPM of coal-derived syngas.

  19. High efficiency nanocomposite sorbents for CO2 capture based on amine-functionalized mesoporous capsules

    KAUST Repository

    Qi, Genggeng; Wang, Yanbing; Estevez, Luis; Duan, Xiaonan; Anako, Nkechi; Park, Ah-Hyung Alissa; Li, Wen; Jones, Christopher W.; Giannelis, Emmanuel P.

    2011-01-01

    A novel high efficiency nanocomposite sorbent for CO2 capture has been developed based on oligomeric amine (polyethylenimine, PEI, and tetraethylenepentamine, TEPA) functionalized mesoporous silica capsules. The newly synthesized sorbents exhibit extraordinary capture capacity up to 7.9 mmol g-1 under simulated flue gas conditions (pre-humidified 10% CO 2). The CO2 capture kinetics were found to be fast and reached 90% of the total capacities within the first few minutes. The effects of the mesoporous capsule features such as particle size and shell thickness on CO2 capture capacity were investigated. Larger particle size, higher interior void volume and thinner mesoporous shell thickness all improved the CO2 capacity of the sorbents. PEI impregnated sorbents showed good reversibility and stability during cyclic adsorption-regeneration tests (50 cycles). © 2011 The Royal Society of Chemistry.

  20. Adsorption of H2O and CO2 on supported amine sorbents

    NARCIS (Netherlands)

    Veneman, Rens; Frigka, Natalia; Zhao, Wenying; Li, Zhenshan; Kersten, Sascha R.A.; Brilman, Derk Willem Frederik

    2015-01-01

    In this work the adsorption of H2O and CO2 on Lewatit VP OC 1065 was studied in view of the potential application of this sorbent in post combustion CO2 capture. Both CO2 and H2O were found to adsorb on the amine active sites present on the pore surface of the sorbent material. However, where the

  1. Synthesis and Application of Iron Oxide/Silica Gel Nanocomposite for Removal of Sulfur Dyes from Aqueous Solutions

    Directory of Open Access Journals (Sweden)

    Naser Tavassoli

    2017-03-01

    Full Text Available Background & Aims of the Study: water pollution by synthetic organic dyes is mainly regarded as environmental and ecological critical issues worldwide. In this research, magnetite iron oxide/silica gel nanocomposite (termed as Fe3O4/SG was synthesized chemically and then used as an effective adsorbent for removal of sulfur dyes from aqueous solution. Materials and Methods: The various parameters such as pH, sorbent dosage, initial dye concentration, contact time and dye solution temperature were investigated in a batch system. The equilibrium data were analyzed by Langmuir and Freundlich isotherm models. Results: The experimental data fit well with pseudo-second-order kinetic model (R2≥0.998 and conformed better to Langmuir isotherm model (R2≥0.997. The maximum adsorption capacity for Fe3O4/SG obtained from the Langmuir model was 11.1mg/g. Evaluation of thermodynamic parameters proved that the adsorption process was normally feasible, spontaneous and exothermic. Conclusion: It can be concluded that the Fe3O4/SG can be considered as a cost-effective and an environmental friendly adsorbent for efficient removal of sulfur dyes from aqueous solutions.

  2. Sulfur isotope studies of biogenic sulfur emissions at Wallops Island, Virginia

    International Nuclear Information System (INIS)

    Hitchcock, D.R.; Black, M.S.; Herbst, R.P.

    1978-03-01

    This research attempted to determine whether it is possible to measure the stable sulfur isotope distributions of atmospheric particulate and gaseous sulphur, and to use this information together with measurements of the ambient levels of sulfur gases and particulate sulfate and sodium in testing certain hypotheses. Sulfur dioxide and particulate sulfur samples were collected at a coastal marine location and their delta (34)S values were determined. These data were used together with sodium concentrations to determine the presence of biogenic sulfur and the identity of the biological processes producing it. Excess (non-seasalt) sulfate levels ranged from 2 to 26 micrograms/cu m and SO2 from 1 to 9 ppb. Analyses of air mass origins and lead concentrations indicated that some anthropogenic contaminants were present on all days, but the isotope data revealed that most of the atmospheric sulfur originated locally from the metabolism of bacterial sulfate reducers on all days, and that the atmospheric reactions leading to the production of sulfate from this biogenic sulfur source are extremely rapid. Delta 34 S values of atmospheric sulfur dioxide correlated well with those of excess sulfate, and implied little or no sulfur isotope fractionation during the oxidation of sulfur gases to sulfate

  3. Novel nanoporous sorbent for solid-phase extraction in petroleum fingerprinting

    Science.gov (United States)

    Alayande, S. Oluwagbemiga; Hlengilizwe, Nyoni; Dare, E. Olugbenga; Msagati, Titus A. M.; Akinlabi, A. Kehinde; Aiyedun, P. O.

    2016-04-01

    Sample preparation is crucial in the analysis of petroleum and its derivatives. In this study, developing affordable sorbent for petroleum fingerprinting analysis using polymer waste such expanded polystyrene was explored. The potential of electrospun expanded polystyrene (EPS) as a sorbent for the solid-phase extraction (SPE) technique was investigated, and its efficiency was compared with commercial cartridges such as alumina, silica and alumina/silica hybrid commercial for petroleum fingerprinting analysis. The chromatograms showed that the packed electrospun EPS fibre demonstrated excellent properties for SPE applications relative to the hybrid cartridges.

  4. Sulfur-Containing Agrochemicals.

    Science.gov (United States)

    Devendar, Ponnam; Yang, Guang-Fu

    2017-10-09

    Modern agricultural chemistry has to support farmers by providing innovative agrochemicals. In this context, the introduction of sulfur atoms into an active ingredient is still an important tool in modulating the properties of new crop-protection compounds. More than 30% of today's agrochemicals contain at least one sulfur atom, mainly in fungicides, herbicides and insecticides. A number of recently developed sulfur-containing agrochemical candidates represent a novel class of chemical compounds with new modes of action, so we intend to highlight the emerging interest in commercially active sulfur-containing compounds. This chapter gives a comprehensive overview of selected leading sulfur-containing pesticidal chemical families namely: sulfonylureas, sulfonamides, sulfur-containing heterocyclics, thioureas, sulfides, sulfones, sulfoxides and sulfoximines. Also, the most suitable large-scale synthetic methods of the recently launched or provisionally approved sulfur-containing agrochemicals from respective chemical families have been highlighted.

  5. Regeneration dynamics of potassium-based sediment sorbents for CO{sub 2} capture

    Energy Technology Data Exchange (ETDEWEB)

    Wang, Li-wei; Diao, Yong-fa; Wang, Lin-lin; Shi, Xiao-fang; Tai, Xiao-yan [Donghua University, Shanghai (China)

    2013-08-15

    Simulating regeneration tests of Potassium-Based sorbents that supported by Suzhou River Channel Sediment were carried out in order to obtain parameters of regeneration reaction. Potassium-based sediment sorbents have a better morphology with the surface area of 156.73 m{sup 2}·g{sup −1}, the pore volume of 357.5x10{sup −3} cm{sup 3}·g{sup −1} and the distribution of pore diameters about 2-20 nm. As a comparison, those of hexagonal potassium-based sorbents are only 2.83 m{sup 2}g{sup −1}, 7.45x10{sup −3} cm{sup 3}g{sup −1} and 1.72-5.4 nm, respectively. TGA analysis shows that the optimum final temperature of regeneration is 200 and the optimum loading is about 40%, with the best heating rate of 10 .deg. C·min{sup −1}. By the modified Coats-Redfern integral method, the activation energy of 40% KHCO{sub 3} sorbents is 102.43 kJ·mol{sup −1}. The results obtained can be used as basic data for designing and operating CO{sub 2} capture process.

  6. Development and thermochemical characterizations of vermiculite/SrBr_2 composite sorbents for low-temperature heat storage

    International Nuclear Information System (INIS)

    Zhang, Y.N.; Wang, R.Z.; Zhao, Y.J.; Li, T.X.; Riffat, S.B.; Wajid, N.M.

    2016-01-01

    Novel EVM/SrBr_2 composite sorbents with different salt contents were developed for low-temperature thermal energy storage (TES). Simulative sorption experiment was conducted to obtain the sorption kinetics diagram and identify threshold salt content that composite sorbents can hold without solution leakage. Distribution of salt embedded in EVM was observed by extreme-resolution scanning electron microscopy (ER-SEM). Thermochemical characterizations including desorption performance and desorption heat were fully investigated by analyzing simultaneous thermal analyzer (STA) results. Results reveal that sorption process of composite sorbents is divided into three parts: water adsorption of EVM, water adsorption of SrBr_2 crystal and liquid-gas absorption of SrBr_2 solution. Since SrBr_2 solution can be hold in macrospores of EVM, water uptake and energy storage density are greatly increased. It appears that the composite sorbent of EVMSrBr_240 is a promising material for thermal energy storage, with water uptake of 0.53 g/g, mass energy storage density of 0.46 kWh/kg and volume energy storage density of 105.36 kWh/m"3. - Highlights: • Vermiculite/SrBr_2 composite sorbents were developed for thermal energy storage. • Water uptake of composite sorbents is divided into three phases. • Energy storage density of each sorption phase is evaluated via calculations. • EVMSrBr_240 is chosen as optimal sorbent without solution leakage.

  7. Removal of dissolved textile dyes from wastewater by a compost sorbent

    Science.gov (United States)

    Tsui, L.S.; Roy, W.R.; Cole, M.A.

    2003-01-01

    The objective of this study was to evaluate the potential for treating dye-contaminated waste streams by sorption using compost as a low-cost sorbent. A mature, thermophilic compost sample was used to sorb CI Acid Black 24, CI Acid Orange 74, CI Basic Blue 9, CI Basic Green 4, CI Direct Blue 71, CI Direct Orange 39, CI Reactive Orange 16 and CI Reactive Red 2 from solution using a batch-sorption method. With the exception of the two reactive dyes, the sorption kinetics were favourable for a continuous-flow treatment process with the compost-dye mixtures reaching a steady state within 3-5 h. Based on limited comparisons, the affinity of the compost for each dye appeared to be competitive with other non-activated carbon sorbents. The results suggest that additional research on using compost as a sorbent for dye-contaminated solutions is warranted.

  8. Aerosol Formation during the Combustion of Straw with Addition of Sorbents

    DEFF Research Database (Denmark)

    Zeuthen, Frederik Jacob; Jensen, Peter Arendt; Jensen, Jørgen P.

    2007-01-01

    , calcium phosphate, Bentonite, ICA5000, and clay. The addition of chalk increased the aerosol mass concentration by 24%. Experiments in a laminar flow aerosol condenser with the six sorbents were carried out in the laboratory using a synthetic flue gas to avoid fluctuations in the alkali feeding......The influence of six sorbents on aerosol formation during the combustion of straw in a 100 MW boiler on a Danish power plant has been studied in full-scale. The following sorbents were studied: ammonium sulfate, monocalcium phosphate, Bentonite, ICA5000, clay, and chalk. Bentonite and ICA5000...... are mixtures of clay minerals and consist mainly of the oxides from Fe, Al, and Si. The straw used was Danish wheat and seed grass. Measurements were also made with increased flow of primary air. The experiments showed between 46% and 70% reduction in particle mass concentrations when adding ammonium sulfate...

  9. Influence of high-temperature steam on the reactivity of CaO sorbent for CO₂ capture.

    Science.gov (United States)

    Donat, Felix; Florin, Nicholas H; Anthony, Edward J; Fennell, Paul S

    2012-01-17

    Calcium looping is a high-temperature CO(2) capture technology applicable to the postcombustion capture of CO(2) from power station flue gas, or integrated with fuel conversion in precombustion CO(2) capture schemes. The capture technology uses solid CaO sorbent derived from natural limestone and takes advantage of the reversible reaction between CaO and CO(2) to form CaCO(3); that is, to achieve the separation of CO(2) from flue or fuel gas, and produce a pure stream of CO(2) suitable for geological storage. An important characteristic of the sorbent, affecting the cost-efficiency of this technology, is the decay in reactivity of the sorbent over multiple CO(2) capture-and-release cycles. This work reports on the influence of high-temperature steam, which will be present in flue (about 5-10%) and fuel (∼20%) gases, on the reactivity of CaO sorbent derived from four natural limestones. A significant increase in the reactivity of these sorbents was found for 30 cycles in the presence of steam (from 1-20%). Steam influences the sorbent reactivity in two ways. Steam present during calcination promotes sintering that produces a sorbent morphology with most of the pore volume associated with larger pores of ∼50 nm in diameter, and which appears to be relatively more stable than the pore structure that evolves when no steam is present. The presence of steam during carbonation reduces the diffusion resistance during carbonation. We observed a synergistic effect, i.e., the highest reactivity was observed when steam was present for both calcination and carbonation.

  10. CNTs reinforced super-hydrophobic-oleophilic electrospun polystyrene oil sorbent for enhanced sorption capacity and reusability

    KAUST Repository

    Wu, Jingya

    2016-12-05

    To meet the challenges of global oil spills and oil-water contamination, the development of a low-cost and reusable sorbents with good hydrophobicity and oleophilic nature is crucial. In this study, functionalized carbon nanotubes (CNTs) were wrapped in polystyrene (PS) polymer (PS-CNTs) and electrospun to create an effective and rigid sorbent for oil. Covalent modification and fluorination of CNTs improved their dispersibility and interfacial interaction with the polymer, resulting in a well-aligned CNTs configuration inside the porous fiber structure. Interestingly, the oil sorption process using PS-CNTs was observed to have two phases. First, the oil swiftly entered the membrane pores formed by interconnected nanofibers due to oleophilic properties of the micro-sized void. In the second phase, the oil not only moved to nano interior spaces of the fibers by capillary forces but also adsorbed on the surface of fibers where the latter was retained due to Van der Waals force. The sorption process fits well with the intra particle diffusion model. Maximum oil sorption capacity of the PS-CNTs sorbent for sunflower oil, peanut oil, and motor oils were 116, 123, and 112 g/g, respectively, which was 65% higher than that of the PS sorbent without CNTs. Overall, a significant increase in the porosity, surface area, water contact angle, and oleophilic nature was observed for the PS-CNTs composite sorbents. Not only did the PS-CNTs sorbents exhibited a promising oil sorption capacity but also showed potential for reusability, which is an important factor to be considered in determining the overall performance of the sorbent and its environmental impacts.

  11. CNTs reinforced super-hydrophobic-oleophilic electrospun polystyrene oil sorbent for enhanced sorption capacity and reusability

    KAUST Repository

    Wu, Jingya; Kyoungjin An, Alicia; Guo, Jiaxin; Lee, Eui-Jong; Usman Farid, Muhammad; Jeong, Sanghyun

    2016-01-01

    To meet the challenges of global oil spills and oil-water contamination, the development of a low-cost and reusable sorbents with good hydrophobicity and oleophilic nature is crucial. In this study, functionalized carbon nanotubes (CNTs) were wrapped in polystyrene (PS) polymer (PS-CNTs) and electrospun to create an effective and rigid sorbent for oil. Covalent modification and fluorination of CNTs improved their dispersibility and interfacial interaction with the polymer, resulting in a well-aligned CNTs configuration inside the porous fiber structure. Interestingly, the oil sorption process using PS-CNTs was observed to have two phases. First, the oil swiftly entered the membrane pores formed by interconnected nanofibers due to oleophilic properties of the micro-sized void. In the second phase, the oil not only moved to nano interior spaces of the fibers by capillary forces but also adsorbed on the surface of fibers where the latter was retained due to Van der Waals force. The sorption process fits well with the intra particle diffusion model. Maximum oil sorption capacity of the PS-CNTs sorbent for sunflower oil, peanut oil, and motor oils were 116, 123, and 112 g/g, respectively, which was 65% higher than that of the PS sorbent without CNTs. Overall, a significant increase in the porosity, surface area, water contact angle, and oleophilic nature was observed for the PS-CNTs composite sorbents. Not only did the PS-CNTs sorbents exhibited a promising oil sorption capacity but also showed potential for reusability, which is an important factor to be considered in determining the overall performance of the sorbent and its environmental impacts.

  12. Extraction of trace nitrophenols in environmental water samples using boronate affinity sorbent

    International Nuclear Information System (INIS)

    Zhang, Yong; Mei, Meng; Huang, Xiaojia; Yuan, Dongxing

    2015-01-01

    In this research, the applicability of a new sorbent based on boronate affinity material is demonstrated. For this purpose, six strong polar nitrophenols were selected as models which are difficult to be extracted in neutral form (only based on hydrophobic interactions). The extracted nitrophenols were separated and determined by high-performance liquid chromatography with diode array detection. The sorbent was synthesized by in situ copolymerization of 3-acrylamidophenylboronic acid and divinylbenzene using dimethyl sulfoxide and azobisisobutyronitrile as porogen solvent and initiator, respectively. The effect of the preparation parameters in the polymerization mixture on extraction performance was investigated in detail. The size and morphology of the sorbent have been characterized via different techniques such as infrared spectroscopy, elemental analysis, scanning electron microscopy and mercury intrusion porosimetry. The important parameters influencing the extraction efficiency were studied and optimized thoroughly. Under the optimum extraction conditions, the limits of detection (S/N = 3) and limits of quantification (S/N = 10) for the target nitrophenols were 0.097–0.28 and 0.32–0.92 μg/L, respectively. The precision of the proposed method was evaluated in terms of intra- and inter-assay variability calculated as RSD, and it was found that the RSDs were all below 9%. Finally, the developed method was successfully applied for environmental water samples such as wastewater, tap, lake and river water. The recoveries varied within the range of 71.2–115% with RSD below 11% in all cases. The results well demonstrate that the new boronate affinity sorbent can extract nitrophenols effectively through multi-interactions including boron–nitrogen coordination, hydrogen-bond and hydrophobic interactions between sorbent and analytes. - Highlights: • A new boronate affinity sorbent (BAS) was prepared. • The BAS was used as the extractive medium of stir

  13. A Nacre-Like Carbon Nanotube Sheet for High Performance Li-Polysulfide Batteries with High Sulfur Loading.

    Science.gov (United States)

    Pan, Zheng-Ze; Lv, Wei; He, Yan-Bing; Zhao, Yan; Zhou, Guangmin; Dong, Liubing; Niu, Shuzhang; Zhang, Chen; Lyu, Ruiyang; Wang, Cong; Shi, Huifa; Zhang, Wenjie; Kang, Feiyu; Nishihara, Hirotomo; Yang, Quan-Hong

    2018-06-01

    Lithium-sulfur (Li-S) batteries are considered as one of the most promising energy storage systems for next-generation electric vehicles because of their high-energy density. However, the poor cyclic stability, especially at a high sulfur loading, is the major obstacles retarding their practical use. Inspired by the nacre structure of an abalone, a similar configuration consisting of layered carbon nanotube (CNT) matrix and compactly embedded sulfur is designed as the cathode for Li-S batteries, which are realized by a well-designed unidirectional freeze-drying approach. The compact and lamellar configuration with closely contacted neighboring CNT layers and the strong interaction between the highly conductive network and polysulfides have realized a high sulfur loading with significantly restrained polysulfide shuttling, resulting in a superior cyclic stability and an excellent rate performance for the produced Li-S batteries. Typically, with a sulfur loading of 5 mg cm -2 , the assembled batteries demonstrate discharge capacities of 1236 mAh g -1 at 0.1 C, 498 mAh g -1 at 2 C and moreover, when the sulfur loading is further increased to 10 mg cm -2 coupling with a carbon-coated separator, a superhigh areal capacity of 11.0 mAh cm -2 is achieved.

  14. High Purity Hydrogen Production with In-Situ Carbon Dioxide and Sulfur Capture in a Single Stage Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Nihar Phalak; Shwetha Ramkumar; Daniel Connell; Zhenchao Sun; Fu-Chen Yu; Niranjani Deshpande; Robert Statnick; Liang-Shih Fan

    2011-07-31

    Enhancement in the production of high purity hydrogen (H{sub 2}) from fuel gas, obtained from coal gasification, is limited by thermodynamics of the water gas shift (WGS) reaction. However, this constraint can be overcome by conducting the WGS in the presence of a CO{sub 2}-acceptor. The continuous removal of CO{sub 2} from the reaction mixture helps to drive the equilibrium-limited WGS reaction forward. Since calcium oxide (CaO) exhibits high CO{sub 2} capture capacity as compared to other sorbents, it is an ideal candidate for such a technique. The Calcium Looping Process (CLP) developed at The Ohio State University (OSU) utilizes the above concept to enable high purity H{sub 2} production from synthesis gas (syngas) derived from coal gasification. The CLP integrates the WGS reaction with insitu CO{sub 2}, sulfur and halide removal at high temperatures while eliminating the need for a WGS catalyst, thus reducing the overall footprint of the hydrogen production process. The CLP comprises three reactors - the carbonator, where the thermodynamic constraint of the WGS reaction is overcome by the constant removal of CO{sub 2} product and high purity H{sub 2} is produced with contaminant removal; the calciner, where the calcium sorbent is regenerated and a sequestration-ready CO{sub 2} stream is produced; and the hydrator, where the calcined sorbent is reactivated to improve its recyclability. As a part of this project, the CLP was extensively investigated by performing experiments at lab-, bench- and subpilot-scale setups. A comprehensive techno-economic analysis was also conducted to determine the feasibility of the CLP at commercial scale. This report provides a detailed account of all the results obtained during the project period.

  15. Investigation on gasoline deep desulfurization for fuel cell applications

    International Nuclear Information System (INIS)

    Zhang, J.C.; Song, L.F.; Hu, J.Y.; Ong, S.L.; Ng, W.J.; Lee, L.Y.; Wang, Y.H.; Zhao, J.G.; Ma, R.Y.

    2005-01-01

    The effect of adding some amounts of cerium into Zn-Fe-O/Al 2 O 3 sorbent on its performance of removal of organic sulfur compounds from gasoline by adsorption was studied in this paper. It showed that the ideal compositions for the preparation of Zn-Fe-Ce-O/Al 2 O 3 consisted of 4.54 wt.% ZnO, 2.25 wt.% Fe 2 O 3 and 2.5 wt.% CeO 2 , respectively, shortened as AZFC 0.52 . Further study indicated that this sorbent could be well regenerated at 250 deg. C with gas mixtures containing 6.0 vol.% steam + air and 2400 ml h -1 ml -1 gas space velocity. At those regenerated conditions and 60 deg. C adsorption temperature, the AZFC 0.52 sorbent had better desulfurization stability, which was confirmed by typical characterization results using BET, XRD and SEM apparatus. This implied that the AZFC 0.52 sorbent could be an ideal sorbent for removal of organic sulfur compounds from gasoline

  16. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    International Nuclear Information System (INIS)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; William J. McMichael; Douglas P. Harrison; Ya Liang

    2002-01-01

    The objective of this project is to develop a simple, inexpensive process to separate CO(sub 2) as an essentially pure stream from a fossil fuel combustion system using a regenerable, sodium-based sorbent. The sorbents being investigated in this project are primarily alkali carbonates, and particularly sodium carbonate and potassium carbonate, which are converted to bicarbonates, through reaction with carbon dioxide and water vapor. Bicarbonates are regenerated to carbonates when heated, producing a nearly pure CO(sub 2) stream after condensation of water vapor. This quarter, electrobalance tests conducted at LSU indicated that exposure of sorbent to water vapor prior to contact with carbonation gas does not significantly increase the reaction rate. Calcined fine mesh trona has a greater initial carbonation rate than calcined sodium bicarbonate, but appears to be more susceptible to loss of reactivity under severe calcination conditions. The Davison attrition indices for Grade 5 sodium bicarbonate, commercial grade sodium carbonate and extra fine granular potassium carbonate were, as tested, outside of the range suitable for entrained bed reactor testing. Fluidized bed testing at RTI indicated that in the initial stages of reaction potassium carbonate removed 35% of the carbon dioxide in simulated flue gas, and is reactive at higher temperatures than sodium carbonate. Removals declined to 6% when 54% of the capacity of the sorbent was exhausted. Carbonation data from electrobalance testing was correlated using a shrinking core reaction model. The activation energy of the reaction of sodium carbonate with carbon dioxide and water vapor was determined from nonisothermal thermogravimetry

  17. Heat recovery from sorbent-based CO.sub.2 capture

    Science.gov (United States)

    Jamal, Aqil; Gupta, Raghubir P

    2015-03-10

    The present invention provides a method of increasing the efficiency of exothermic CO.sub.2 capture processes. The method relates to withdrawing heat generated during the exothermic capture of CO.sub.2 with various sorbents via heat exchange with a working fluid. The working fluid is provided at a temperature and pressure such that it is in the liquid state, and has a vaporization temperature in a range such that the heat arising from the reaction of the CO.sub.2 and the sorbent causes a phase change from liquid to vapor state in whole or in part and transfers heat from to the working fluid. The resulting heated working fluid may subsequently be used to generate power.

  18. Arsenic removal using natural biomaterial-based sorbents.

    Science.gov (United States)

    Ansone, Linda; Klavins, Maris; Viksna, Arturs

    2013-10-01

    Arsenic contamination of water is a major problem worldwide. A possible solution can be approached through developing new sorbents based on cost-effective and environmentally friendly natural biomaterials. We have developed new sorbents based on biomaterial impregnation with iron oxyhydroxide. In this study, raw peat material, iron-modified peat, iron-modified biomass (shingles, straw, sands, cane and moss) as well as iron humate were used for the removal of arsenate from contaminated water. The highest sorption capacity was observed in iron-modified peat, and kinetic studies indicated that the amount of arsenic sorbed on this material exceeds 90 % in 5 h. Arsenate sorption on iron-modified peat is characterised by the pseudo-second-order mechanism. The results of arsenic sorption in the presence of competing substances indicated that sulphate, nitrate, chloride and tartrate anions have practically no influence on As(V) sorption onto Fe-modified peat, whereas the presence of phosphate ions and humic acid significantly lowers the arsenic removal efficiency.

  19. Super-Hydrophobic High Throughput Electrospun Cellulose Acetate (CA) Nanofibrous Mats as Oil Selective Sorbents

    Science.gov (United States)

    Han, Chao

    The threat of oil pollution increases with the expansion of oil exploration and production activities, as well as the industrial growth around the world. Use of sorbents is a common method to deal with the oil spills. In this work, an advanced sorbent technology is described. A series of non-woven Cellulose Acetate (CA) nanofibrous mats with a 3D fibrous structure were synthesized by a novel high-throughput electrospinning technique. The precursor was solutions of CA/ acetic acid-acetone in various concentrations. Among them, 15.0% CA exhibits a superhydrophobic surface property, with a water contact angle of 128.95°. Its oil sorption capacity is many times higher the oil sorption capacity of the best commercial sorbent available in the market. Also, it showed good buoyancy properties on the water both as dry-mat and oil-saturated mat. In addition, it is biodegradable, easily available, easily manufactured, so the CA nanofibrous mat is an excellent candidate as oil sorbent for oil spill in water treatment.

  20. Catalyst for the reduction of sulfur dioxide to elemental sulfur

    Science.gov (United States)

    Jin, Y.; Yu, Q.; Chang, S.G.

    1996-02-27

    The inventive catalysts allow for the reduction of sulfur dioxide to elemental sulfur in smokestack scrubber environments. The catalysts have a very high sulfur yield of over 90% and space velocity of 10,000 h{sup {minus}1}. They also have the capacity to convert waste gases generated during the initial conversion into elemental sulfur. The catalysts have inexpensive components, and are inexpensive to produce. The net impact of the invention is to make this technology practically available to industrial applications. 21 figs.

  1. Effect of cerium oxide doping on the performance of CaO-based sorbents during calcium looping cycles.

    Science.gov (United States)

    Wang, Shengping; Fan, Shasha; Fan, Lijing; Zhao, Yujun; Ma, Xinbin

    2015-04-21

    A series of CaO-based sorbents were synthesized through a sol-gel method and doped with different amounts of CeO2. The sorbent with a Ca/Ce molar ratio of 15:1 showed an excellent absorption capacity (0.59 gCO2/g sorbent) and a remarkable cycle durability (up to 18 cycles). The admirable capture performance of CaCe-15 was ascribed to its special morphology formed by the doping of CeO2 and the well-distributed CeO2 particles. The sorbents doped with CeO2 possessed a loose shell-connected cross-linking structure, which was beneficial for the contact between CaO and CO2. CaO and CeO2 were dispersed homogeneously, and the existence of CeO2 also decreased the grain size of CaO. The well-dispersed CeO2, which could act as a barrier, effectively prevented the CaO crystallite from growing and sintering, thus the sorbent exhibited outstanding stability. The doping of CeO2 also improved the carbonation rate of the sorbent, resulting in a high capacity in a short period of time.

  2. Anionic sorbents for arsenic and technetium species

    International Nuclear Information System (INIS)

    Lucero, Daniel A.; Moore, Robert Charles; Bontchev, Ranko Panayotov; Hasan, Ahmed Ali Mohamed; Zhao, Hongting; Salas, Fred Manuel; Holt, Kathleen Caroline

    2003-01-01

    Two sorbents, zirconium coated zeolite and magnesium hydroxide, were tested for their effectiveness in removing arsenic from Albuquerque municipal water. Results for the zirconium coated zeolite indicate that phosphate present in the water interfered with the sorption of arsenic. Additionally, there was a large quantity of iron and copper present in the water, corrosion products from the piping system, which may have interfered with the uptake of arsenic by the sorbent. Magnesium hydroxide has also been proven to be a strong sorbent for arsenic as well as other metals. Carbonate, present in water, has been shown to interfere with the sorption of arsenic by reacting with the magnesium hydroxide to form magnesium carbonate. The reaction mechanism was investigated by FT-IR and shows that hydrogen bonding between an oxygen on the arsenic species and a hydrogen on the Mg(OH)2 is most likely the mechanism of sorption. This was also confirmed by RAMAN spectroscopy and XRD. Technetium exists in multiple oxidation states (IV and VII) and is easily oxidized from the relatively insoluble Tc(IV) form to the highly water soluble and mobile Tc(VII) form. The two oxidation states exhibit different sorption characteristics. Tc(VII) does not sorb to most materials whereas Tc(IV) will strongly sorb to many materials. Therefore, it was determined that it is necessary to first reduce the Tc (using SnCl2) before sorption to stabilize Tc in the environment. Additionally, the effect of carbonate and phosphate on the sorption of technetium by hydroxyapatite was studied and indicated that both have a significant effect on reducing Tc sorption

  3. Mixed and Doped Solid Sorbents for CO2 Capture Applications

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Yuhua [National Energy Technology Lab. (NETL), Albany, OR (United States)

    2016-06-14

    The objectives of this presentation are to capture CO2 we need materials with optimal performance and low costs; establish a theoretical procedure to identify most potential candidates of CO2 solid sorbents from a large solid material databank; computational synthesis new materials to fit industrial needs; and explore the optimal working conditions for the promised CO2 solid sorbents, especially from room to warm T ranges with optimal energy usage.

  4. Sulfur-binding in recent environments: II. Speciation of sulfur and iron and implications for the occurrence of organo-sulfur compounds

    Science.gov (United States)

    Hartgers, Walter A.; Lòpez, Jordi F.; Sinninghe Damsté, Jaap S.; Reiss, Christine; Maxwell, James R.; Grimalt, Joan O.

    1997-11-01

    Speciation of iron and sulfur species was determined for two recent sediments (La Trinitat and Lake Cisó) which were deposited in environments with a high biological productivity and sulfate-reducing activity. In sediments from calcite ponds of La Trinitat an excess of reactive iron species (iron monosulfides, iron hydroxides) results in a depletion of reactive sulfur which is accompanied by a virtual absence of organo-sulfur compounds, both in low (LMW) and high molecular-weight (HMW) fractions. Small amounts of phytanyl and highly branched isoprenoid (HBI) thiophenes in the extract demonstrate that these molecules exhibit a higher reactivity towards reduced sulfur species as compared to detrital iron. Euxinic sediments from Lake Cisó are characterised by an excess of reduced sulfur species which can rapidly trap reactive iron. High concentrations of H 2S results in the formation of organo-sulfur compounds which were encountered in both LMW and HMW fractions. The major part of the organic sulfur is bound to the carbohydrate portion of woody tissues, whose presence was revealed by a specific alkylthiophene distribution in the flash pyrolysate and by Li/EtNH 2 desulfurisation of the kerogen which resulted in the solubilisation of the sulfur-enriched hemicellulose fraction. Relatively high amounts of sulfurised C 25 HBI compounds in the sediment extract of Lake Cisó reflect the incorporation of sulfur into algal derived organic matter upon early diagenesis. The combined approach of the speciation of iron and sulfur species and the molecular analysis of sedimentary fractions demonstrates that abiotic sulfur binding to organic matter occurs at the earliest stages of diagenesis under specific depositional conditions (anoxic, stratified water column) in which an excess of reduced sulfur species relative to the amount of reactive iron is a controlling factor.

  5. CO{sub 2} capture efficiency and energy requirement analysis of power plant using modified calcium-based sorbent looping cycle

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.J.; Zhao, C.S.; Chen, H.C.; Ren, Q.Q.; Duan, L.B. [Southeast University, Nanjing (China). School of Energy & Environment

    2011-03-15

    This paper examines the average carbonation conversion, CO{sub 2} capture efficiency and energy requirement for post-combustion CO{sub 2} capture system during the modified calcium-based sorbent looping cycle. The limestone modified with acetic acid solution, i.e. calcium acetate is taken as an example of the modified calcium-based sorbents. The modified limestone exhibits much higher average carbonation conversion than the natural sorbent under the same condition. The CO{sub 2} capture efficiency increases with the sorbent flow ratios. Compared with the natural limestone, much less makeup mass flow of the recycled and the fresh sorbent is needed for the system when using the modified limestone at the same CO{sub 2} capture efficiency. Achieving 0.95 of CO{sub 2} capture efficiency without sulfation, 272 kJ/mol CO{sub 2} is required in the calciner for the natural limestone, whereas only 223 kJ/mol CO{sub 2} for the modified sorbent. The modified limestone possesses greater advantages in CO{sub 2} capture efficiency and energy consumption than the natural sorbent. When the sulfation and carbonation of the sorbents take place simultaneously, more energy is required. It is significantly necessary to remove SO{sub 2} from the flue gas before it enters the carbonator in order to reduce energy consumption in the calciner.

  6. Lithium sulfur batteries and electrolytes and sulfur cathodes thereof

    Science.gov (United States)

    Visco, Steven J.; Goncharenko, Nikolay; Nimon, Vitaliy; Petrov, Alexei; Nimon, Yevgeniy S.; De Jonghe, Lutgard C.; Katz, Bruce D.; Loginova, Valentina

    2017-05-23

    Lithium sulfur battery cells that use water as an electrolyte solvent provide significant cost reductions. Electrolytes for the battery cells may include water solvent for maintaining electroactive sulfur species in solution during cell discharge and a sufficient amount of a cycle life-enhancing compound that facilitates charging at the cathode. The combination of these two components enhances one or more of the following cell attributes: energy density, power density and cycle life. For instance, in applications where cost per Watt-Hour (Wh) is paramount, such as grid storage and traction applications, the use of an aqueous electrolyte in combination with inexpensive sulfur as the cathode active material can be a key enabler for the utility and automotive industries, for example, providing a cost effective and compact solution for load leveling, electric vehicles and renewable energy storage. Sulfur cathodes, and methods of fabricating lithium sulfur cells, in particular for loading lithium sulfide into the cathode structures, provide further advantages.

  7. Optimizing the Costs of Solid Sorbent-Based CO2 Capture Process Through Heat Integration

    Energy Technology Data Exchange (ETDEWEB)

    Sjostrom, Sharon [Ada-Es, Inc., Highlands Ranch, CO (United States)

    2016-03-18

    The focus of this project was the ADAsorb™ CO2 Capture Process, a temperature-swing adsorption process that incorporates a three-stage fluidized bed as the adsorber and a single-stage fluidized bed as the regenerator. ADAsorb™ system was designed, fabricated, and tested under DOE award DEFE0004343. Two amine-based sorbents were evaluated in conjunction with the ADAsorb™ process: “BN”, an ion-exchange resin; and “OJ”, a metal organic framework (MOF) sorbent. Two cross heat exchanger designs were evaluated for use between the adsorber and regenerator: moving bed and fluidized bed. The fluidized bed approach was rejected fairly early in the project because the additional electrical load to power blowers or fans to overcome the pressure drop required for fluidization was estimated to be nominally three times the electrical power that could be generated from the steam saved through the use of the cross heat exchanger. The Energy Research Center at Lehigh University built and utilized a process model of the ADAsorb™ capture process and integrated this model into an existing model of a supercritical PC power plant. The Lehigh models verified that, for the ADAsorb™ system, the largest contributor to parasitic power was lost electrical generation, which was primarily electric power which the host plant could not generate due to the extraction of low pressure (LP) steam for sorbent heating, followed by power for the CO2 compressor and the blower or fan power required to fluidize the adsorber and regenerator. Sorbent characteristics such as the impacts of moisture uptake, optimized adsorption and regeneration temperature, and sensitivity to changes in pressure were also included in the modeling study. Results indicate that sorbents which adsorb more than 1-2% moisture by weight are unlikely to be cost competitive unless they have an extremely high CO2 working capacity that well exceeds 15% by weight. Modeling also revealed

  8. Comments on "Ceria-Zirconia High-Temperature Desulfurization Sorbents".

    Czech Academy of Sciences Publication Activity Database

    Hartman, Miloslav; Trnka, Otakar

    2006-01-01

    Roč. 45, č. 4 (2006), s. 1548-1549 ISSN 0888-5885 Institutional research plan: CEZ:AV0Z40720504 Keywords : hydrogen sulfide * desulfurization * cerium sorbent Subject RIV: CI - Industrial Chemistry, Chemical Engineering Impact factor: 1.518, year: 2006

  9. Analysis of Ethane and Diethylbenzene Bridged Sorbents

    Science.gov (United States)

    2017-12-13

    Textiles modified in this manner have been shown to reduce or eliminate transport of chemical warfare agents and simulants across the fabric barrier...B.J. Johnson; B.J. Melde; M.H. Moore; A.P. Malanoski; J.R. Taft, "Improving sorbents for glycerol capture in biodiesel refinement," Materials 10

  10. Capillary Columns with a Sorbent Based on Functionalized Poly(1-Trimethylsilyl-1-Propyne) for the Elution Analysis of Natural Gas

    Science.gov (United States)

    Yakovleva, E. Yu.; Patrushev, Yu. V.; Pai, Z. P.

    2018-05-01

    The chromatographic properties of capillary columns prepared using functionalized poly(1- trimethylsilyl-1-propyne) (PTMSP) are evaluated and compared with the performance of a commercial column with divinylbenzene polymer sorbent. The loading capacity of a PTMSP column with dimensions of 30 m × 0.53 mm × 0.8 μm is shown to be about 2.5 times higher than that of a divinylbenzene polymer column with a diameter of 0.32 mm and a film thickness of 10 μm. The increased value of the background current for PTMSP columns at 220°C is explained by the presence of non-polar bulky substituents in the polymer chain. Differences in the order of elution are found for the following pairs of compounds: acetylene-ethylene; ethane-water; butene-1-isobutane; and sulfur dioxide-carbonyl sulfide. On a column with the functionalized PTMC, analysis of a mixture composition close to natural gas is found to be complete within 27 min.

  11. Graphene oxide as a sulfur immobilizer in high performance lithium/sulfur cells

    Science.gov (United States)

    Zhang, Yuegang; Cairns, Elton J.; Ji, Liwen; Rao, Mumin

    2017-06-06

    The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Embodiments of the invention use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach obtains a uniform and thin (.about.tens of nanometers) sulfur coating on graphene oxide sheets by a chemical reaction-deposition strategy and a subsequent low temperature thermal treatment process. Strong interaction between graphene oxide and sulfur or polysulfides demonstrate lithium/sulfur cells with a high reversible capacity of 950-1400 mAh g.sup.-1, and stable cycling for more than 50 deep cycles at 0.1 C.

  12. Graphene oxide as a sulfur immobilizer in high performance lithium/sulfur cells

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, Yuegang; Cairns, Elton J.; Ji, Liwen; Rao, Mumin

    2017-12-26

    The loss of sulfur cathode material as a result of polysulfide dissolution causes significant capacity fading in rechargeable lithium/sulfur cells. Embodiments of the invention use a chemical approach to immobilize sulfur and lithium polysulfides via the reactive functional groups on graphene oxide. This approach obtains a uniform and thin (.about.tens of nanometers) sulfur coating on graphene oxide sheets by a chemical reaction-deposition strategy and a subsequent low temperature thermal treatment process. Strong interaction between graphene oxide and sulfur or polysulfides demonstrate lithium/sulfur cells with a high reversible capacity of 950-1400 mAh g.sup.-1, and stable cycling for more than 50 deep cycles at 0.1 C.

  13. The use of lightweight expanded clay aggregate (LECA) as sorbent for PAHs removal from water

    International Nuclear Information System (INIS)

    Nkansah, Marian Asantewah; Christy, Alfred A.; Barth, Tanja; Francis, George William

    2012-01-01

    Highlights: ► Effect of contact time on sorption PAH by LECA. ► Effect of mass of sorbent (LECA) on sorption of PAH. ► Sorption Isotherms for PAH-LECA interaction. - Abstract: Lightweight expanded clay aggregate (LECA) has been explored as a sorbent for the removal of PAHs (phenanthrene, fluoranthene and pyrene) from water. The efficacy of LECA as a sorbent for PAHs was assessed using contact time, mass of sorbent and sorption isotherms in a series of batch experiments. Maximum (optimum) sorption was reached at 21 h after which the amount of PAHs sorbed remained almost constant. Batch experiments were conducted by shaking a 100 ml solution mixture of individual PAHs (containing 0.02 mg/L) with LECA. The maximum sorption was 70.70, 70.82 and 72.12%, respectively for phenanthrene, fluoranthene and pyrene when a mass of 0.2 g of sorbent was used. There was an increase in sorption as a result of an increase in mass of sorbent until a maximum was reached at a mass of 4.0 g LECA with 92.61, 93.91 and 94.15% sorption of phenanthrene, fluoranthene and pyrene respectively. Sorption data were fitted to the linearised forms of the Freundlich and Langmuir isotherm models to determine the water-LECA partitioning coefficient. Physical sorption caused by the aromatic nature of the compounds was the main mechanism that governed the removal process while the hydrophobicity of the PAHs also influenced the sorption capacity. LECA can be used as an alternative method for aqueous PAHs removal.

  14. Preparation and investigation of ion exchange properties of sorbent based on activated carbon BAU and zirconium hydroxide

    International Nuclear Information System (INIS)

    Blokhin, A.A.; Semenov, M.I.; Taushkanov, V.P.; Andronov, E.A.

    1978-01-01

    The method of obtaining the sorbent based on the activated carbon and zirconium hydroxide, performed by carbon soaking by zirconium salt solution, hydrolytic decomposition, being in salt pores by ammonia solution and drying of the obtained sorbet in the air at the temperature of 105-115 deg. The kinetic characteristics of the obtained sorbent in the wide range of pH value of solutions are studied; sodium, chloride, fluoride and phosphate ion sorbtion taken as examples. A high selectivity of the sorbent to phosphate and fluoride ions has been established. The usefullness of the obtained sorbent for extraction of phosphorus microquantities from 1M sodium chloride solution and its concentration at the elution stage is shown

  15. Lanthanide Selective Sorbents: Self-Assembled Monolayers on Mesoporous Supports (SAMMS)

    Energy Technology Data Exchange (ETDEWEB)

    Fryxell, Glen E.; Wu, Hong; Lin, Yuehe; Shaw, Wendy J.; Birnbaum, Jerome C.; Linehan, John C.; Nie, Zimin; Kemner, K. M.; Kelly, Shelley

    2004-11-01

    Through the marriage of mesoporous ceramics with self-assembled monolayer chemistry, the genesis of a powerful new class of environmental sorbent materials has been realized. By coating the mesoporous ceramic backbone with a monolayer terminated with a lanthanide-specific ligand, it is possible to couple high lanthanide binding affinity with the high loading capacity (resulting from the extremely high surface area of the support). This lanthanide-specific ligand field is created by pairing a ''hard'' anionic Lewis base with a suitable synergistic ligand, in a favorable chelating geometry. Details of the synthesis, characterization, lanthanide binding studies, binding kinetics, competition experiments and sorbent regeneration studies are summarized

  16. Lanthanide Selective Sorbents: Self-Assembled Monolayers on Mesoporous Supports (SAMMS)

    Energy Technology Data Exchange (ETDEWEB)

    Fryxell, Glen E.; Wu, Hong; Lin, Yuehe; Shaw, Wendy J.; Birnbaum, Jerome C.; Linehan, John C.; Nie, Zimin; Kemner, Kenneth M.; Kelly, Shelley

    2004-11-01

    Through the marriage of mesoporous ceramics with self-assembled monolayer chemistry, the genesis of a powerful new class of environmental sorbent materials has been realized. By coating the mesoporous ceramic backbone with a monolayer terminated with a lanthanide-specific ligand, it is possible to couple high lanthanide binding affinity with the high loading capacity (resulting from the extremely high surface area of the support). This lanthanide-specific ligand field is created by pairing a “hard” anionic Lewis base with a suitable synergistic ligand, in a favorable chelating geometry. Details of the synthesis, characterization, lanthanide binding studies, binding kinetics, competition experiments and sorbent regeneration studies are summarized.

  17. Theoretical Predictions of the thermodynamic Properties of Solid Sorbents Capture CO2 Applications

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Yuhua; Sorescu, Dan; Luebke David; Pennline, Henry

    2012-05-02

    We are establishing a theoretical procedure to identify most potential candidates of CO{sub 2} solid sorbents from a large solid material databank to meet the DOE programmatic goal for energy conversion; and to explore the optimal working conditions for the promising CO{sub 2} solid sorbents, especially from room to warm T ranges with optimal energy usage, used for both pre- and post-combustion capture technologies.

  18. Method of removing and recovering elemental sulfur from highly reducing gas streams containing sulfur gases

    Science.gov (United States)

    Gangwal, Santosh K.; Nikolopoulos, Apostolos A.; Dorchak, Thomas P.; Dorchak, Mary Anne

    2005-11-08

    A method is provided for removal of sulfur gases and recovery of elemental sulfur from sulfur gas containing supply streams, such as syngas or coal gas, by contacting the supply stream with a catalyst, that is either an activated carbon or an oxide based catalyst, and an oxidant, such as sulfur dioxide, in a reaction medium such as molten sulfur, to convert the sulfur gases in the supply stream to elemental sulfur, and recovering the elemental sulfur by separation from the reaction medium.

  19. Effects of O{sub 2} and SO{sub 2} on the Capture Capacity of a Primary-Amine Based Polymeric CO{sub 2} Sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Hallenbeck, Alexander P; Kitchin, John R

    2013-08-01

    Post combustion CO{sub 2} capture is most commonly carried out using an amine solution that results in a high parasitic energy cost in the stripper unit due to the need to heat the water which comprises a majority of the amine solution. It is also well known that amine solvents suffer from stability issues due to amine leaching and poisoning by flue gas impurities. Solid sorbents provide an alternative to solvent systems that would potentially reduce the energy penalty of carbon capture. However, the cost of using a particular sorbent is greatly affected by the usable lifetime of the sorbent. This work investigated the stability of a primary amine-functionalized ion exchange resin in the presence of O{sub 2} and SO{sub 2}, both of which are constituents of flue gas that have been shown to cause degradation of various amines in solvent processes. The CO{sub 2} capture capacity was measured over multiple capture cycles under continuous exposure to two simulated flue gas streams, one containing 12 vol% CO{sub 2}, 4% O{sub 2}, 84% N{sub 2}, and the other containing 12.5 vol% CO{sub 2}, 4% O{sub 2}, 431 ppm SO{sub 2}, balance N{sub 2} using a custom-built packed bed reactor. The resin maintained its CO{sub 2} capture capacity of 1.31 mol/kg over 17 capture cycles in the presence of O{sub 2} without SO{sub 2}. However, the CO{sub 2} capture capacity of the resin decreased rapidly under exposure to SO{sub 2} by an amount of 1.3 mol/kg over 9 capture cycles. Elemental analysis revealed the resin adsorbed 1.0 mol/kg of SO{sub 2}. Thermal regeneration was determined to not be possible. The poisoned resin was, however, partially regenerated with exposure to 1.5M NaOH for 3 days resulting in a 43% removal of sulfur, determined through elemental analysis, and a 35% recovery of CO{sub 2} capture capacity. Evidence was also found for amine loss upon prolonged (7 days) continuous exposure to high temperatures (120 C) in air. It is concluded that desulfurization of the flue gas

  20. Microbial consortia in mesocosm bioremediation trial using oil sorbents, slow-release fertilizer and bioaugmentation.

    Science.gov (United States)

    Gertler, Christoph; Gerdts, Gunnar; Timmis, Kenneth N; Golyshin, Peter N

    2009-08-01

    An experimental prototype oil boom including oil sorbents, slow-release fertilizers and biomass of the marine oil-degrading bacterium, Alcanivorax borkumensis, was applied for sorption and degradation of heavy fuel oil in a 500-L mesocosm experiment. Fingerprinting of DNA and small subunit rRNA samples for microbial activity conducted to study the changes in microbial communities of both the water body and on the oil sorbent surface showed the prevalence of A. borkumensis on the surface of the oil sorbent. Growth of this obligate oil-degrading bacterium on immobilized oil coincided with a 30-fold increase in total respiration. A number of DNA and RNA signatures of aromatic hydrocarbon-degrading bacteria were detected both in samples of water body and on oil sorbent. Ultimately, the heavy fuel oil in this mesocosm study was effectively removed from the water body. This is the first study to successfully investigate the fate of oil-degrading microbial consortia in an experimental prototype for a bioremediation strategy in offshore, coastal or ship-bound oil spill mitigation using a combination of mechanical and biotechnological techniques.

  1. The life sulfuric: microbial ecology of sulfur cycling in marine sediments.

    Science.gov (United States)

    Wasmund, Kenneth; Mußmann, Marc; Loy, Alexander

    2017-08-01

    Almost the entire seafloor is covered with sediments that can be more than 10 000 m thick and represent a vast microbial ecosystem that is a major component of Earth's element and energy cycles. Notably, a significant proportion of microbial life in marine sediments can exploit energy conserved during transformations of sulfur compounds among different redox states. Sulfur cycling, which is primarily driven by sulfate reduction, is tightly interwoven with other important element cycles (carbon, nitrogen, iron, manganese) and therefore has profound implications for both cellular- and ecosystem-level processes. Sulfur-transforming microorganisms have evolved diverse genetic, metabolic, and in some cases, peculiar phenotypic features to fill an array of ecological niches in marine sediments. Here, we review recent and selected findings on the microbial guilds that are involved in the transformation of different sulfur compounds in marine sediments and emphasise how these are interlinked and have a major influence on ecology and biogeochemistry in the seafloor. Extraordinary discoveries have increased our knowledge on microbial sulfur cycling, mainly in sulfate-rich surface sediments, yet many questions remain regarding how sulfur redox processes may sustain the deep-subsurface biosphere and the impact of organic sulfur compounds on the marine sulfur cycle. © 2017 The Authors. Environmental Microbiology published by Society for Applied Microbiology and John Wiley & Sons Ltd.

  2. Sulfur Removal by Adding Iron During the Digestion Process of High-sulfur Bauxite

    Science.gov (United States)

    Zhanwei, Liu; Hengwei, Yan; Wenhui, Ma; Keqiang, Xie; Dunyong, Li; Licong, Zheng; Pengfei, Li

    2018-04-01

    This paper proposes a novel approach to sulfur removal by adding iron during the digestion process. Iron can react with high-valence sulfur (S2O3 2-, SO3 2-, SO4 2-) to generate S2- at digestion temperature, and then S2- enter red mud in the form of Na3FeS3 to be removed. As iron dosage increases, high-valence sulfur concentration decreases, but the concentration of S2- increases; sulfur digestion rate decreases while sulfur content in red mud markedly increases; the alumina digestion rate, conversely, remains fairly stable. So sulfur can be removed completely by adding iron in digestion process, which provide a theoretical basis for the effective removal of sulfur in alumina production process.

  3. Nanostructured sulfur cathodes

    KAUST Repository

    Yang, Yuan

    2013-01-01

    Rechargeable Li/S batteries have attracted significant attention lately due to their high specific energy and low cost. They are promising candidates for applications, including portable electronics, electric vehicles and grid-level energy storage. However, poor cycle life and low power capability are major technical obstacles. Various nanostructured sulfur cathodes have been developed to address these issues, as they provide greater resistance to pulverization, faster reaction kinetics and better trapping of soluble polysulfides. In this review, recent developments on nanostructured sulfur cathodes and mechanisms behind their operation are presented and discussed. Moreover, progress on novel characterization of sulfur cathodes is also summarized, as it has deepened the understanding of sulfur cathodes and will guide further rational design of sulfur electrodes. © 2013 The Royal Society of Chemistry.

  4. Evaluation of hydrous ferric oxide loaded activated carbon as a granular composite sorbent for radiostrontium

    International Nuclear Information System (INIS)

    Samanta, S.K.

    1997-01-01

    A composite sorbent was prepared in granular form by depositing hydrous ferric oxide inside the pores of activated carbon. The composite sorbent was found to show excellent sorption of radiostrontium in the presence of high sodium concentration under alkaline conditions. (author). 3 refs., 2 figs., 1 tab

  5. Enhanced capture of elemental mercury by bamboo-based sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Tan, Zengqiang [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Xiang, Jun, E-mail: xiangjun@mail.hust.edu.cn [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Su, Sheng, E-mail: susheng_sklcc@hotmail.com [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China); Zeng, Hancai; Zhou, Changsong; Sun, Lushi; Hu, Song; Qiu, Jianrong [State Key Laboratory of Coal Combustion, Huazhong University of Science and Technology, Wuhan, Hubei 430074 (China)

    2012-11-15

    Highlights: Black-Right-Pointing-Pointer The KI-modified BC has excellent capacity for elemental mercury removal. Black-Right-Pointing-Pointer The chemisorption plays a dominant role for the modified BC materials. Black-Right-Pointing-Pointer The BC-I has strong anti-poisoning ability with the presence of NO or SO{sub 2}. - Abstract: To develop cost-effective sorbent for gas-phase elemental mercury removal, the bamboo charcoal (BC) produced from renewable bamboo and KI modified BC (BC-I) were used for elemental mercury removal. The effect of NO, SO{sub 2} on gas-phase Hg{sup 0} adsorption by KI modified BC was evaluated on a fixed bed reactor using an online mercury analyzer. BET surface area analysis, temperature programmed desorption (TPD) and X-ray photoelectron spectroscopy (XPS) were used to determine the pore structure and surface chemistry of the sorbents. The results show that KI impregnation reduced the sorbents' BET surface area and total pore volume compared with that of the original BC. But the BC-I has excellent adsorption capacity for elemental mercury at a relatively higher temperature of 140 Degree-Sign C and 180 Degree-Sign C. The presence of NO or SO{sub 2} could inhibit Hg{sup 0} capture, but BC-I has strong anti-poisoning ability. The specific reaction mechanism has been further analyzed.

  6. Mechanochemically Activated, Calcium Oxide-Based, Magnesium Oxide-Stabilized Carbon Dioxide Sorbents.

    Science.gov (United States)

    Kurlov, Alexey; Broda, Marcin; Hosseini, Davood; Mitchell, Sharon J; Pérez-Ramírez, Javier; Müller, Christoph R

    2016-09-08

    Carbon dioxide capture and storage (CCS) is a promising approach to reduce anthropogenic CO2 emissions and mitigate climate change. However, the costs associated with the capture of CO2 using the currently available technology, that is, amine scrubbing, are considered prohibitive. In this context, the so-called calcium looping process, which relies on the reversible carbonation of CaO, is an attractive alternative. The main disadvantage of naturally occurring CaO-based CO2 sorbents, such as limestone, is their rapid deactivation caused by thermal sintering. Here, we report a scalable route based on wet mechanochemical activation to prepare MgO-stabilized, CaO-based CO2 sorbents. We optimized the synthesis conditions through a fundamental understanding of the underlying stabilization mechanism, and the quantity of MgO required to stabilize CaO could be reduced to as little as 15 wt %. This allowed the preparation of CO2 sorbents that exceed the CO2 uptake of the reference limestone by 200 %. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Sulfur removal from low-sulfur gasoline and diesel fuel by metal-organic frameworks

    Energy Technology Data Exchange (ETDEWEB)

    Hagen, G.; Haemmerle, M.; Moos, R. [Functional Materials, University of Bayreuth, Bayreuth (Germany); Malkowsky, I.M.; Kiener, C. [BASF SE, Ludwigshafen (Germany); Achmann, S.

    2010-02-15

    Several materials in the class of metal-organic frameworks (MOF) were investigated to determine their sorption characteristics for sulfur compounds from fuels. The materials were tested using different model oils and common fuels such as low-sulfur gasoline or diesel fuel at room temperature and ambient pressure. Thiophene and tetrahydrothiophene (THT) were chosen as model substances. Total-sulfur concentrations in the model oils ranged from 30 mg/kg (S from thiophene) to 9 mg/kg (S from tetrahydrothiophene) as determined by elementary analysis. Initial sulfur contents of 8 mg/kg and 10 mg/kg were identified for low-sulfur gasoline and for diesel fuel, respectively, by analysis of the common liquid fuels. Most of the MOF materials examined were not suitable for use as sulfur adsorbers. However, a high efficiency for sulfur removal from fuels and model oils was noticed for a special copper-containing MOF (copper benzene-1,3,5-tricarboxylate, Cu-BTC-MOF). By use of this material, 78 wt % of the sulfur content was removed from thiophene containing model oils and an even higher decrease of up to 86 wt % was obtained for THT-based model oils. Moreover, the sulfur content of low-sulfur gasoline was reduced to 6.5 mg/kg, which represented a decrease of more than 22 %. The sulfur level in diesel fuel was reduced by an extent of 13 wt %. Time-resolved measurements demonstrated that the sulfur-sorption mainly occurs in the first 60 min after contact with the adsorbent, so that the total time span of the desulfurization process can be limited to 1 h. Therefore, this material seems to be highly suitable for sulfur reduction in commercial fuels in order to meet regulatory requirements and demands for automotive exhaust catalysis-systems or exhaust gas sensors. (Abstract Copyright [2010], Wiley Periodicals, Inc.)

  8. Analysis of Volatile Organic and Sulfur Compounds in Air Near a Pulp Paper Mill in North-Central Idaho

    Science.gov (United States)

    Johnston, N. A. C.; Bundy, B. A.; Andrew, J. P.; Grimm, B. K.; Ketcherside, D.; Rivero-Zevallos, J. A.; Uhlorn, R. P.

    2017-12-01

    Lewiston, Idaho is a small city in the Snake River Valley bordering North-Central Idaho and Southeastern Washington, with a population of over 40,000 including the surrounding areas. One of the main industries and employers in the region is a kraft paper mill in North Lewiston, which results in odorous levels of sulfur air pollutants there. The Idaho Department of Environmental Quality has an air monitoring station in Lewiston but measures only air particulate matter (PM). Surprisingly, not much long-term data exists on this area for specific air constituents such as volatile organics, hazardous air pollutants, and sulfur compounds. One year-long study conducted in 2006-2007 by the Nez Perce Tribe found high formaldehyde levels in the area, and warranted further study in July of 2016-2017. Our ongoing study began in the fall of 2016 and investigates the seasonal air composition in the Lewiston area. Specifically, active air sampling via sorbent tubes and analysis by thermal desorption gas chromatography-mass spectrometry (TD-GC-MS). was utilized to measure over 50 volatile organic compounds, hazardous air pollutants, and sulfurous compounds in ambient air (adapted from EPA Method TO-17). Seasonal, diurnal, and spatial variations in air composition were explored with weekly to monthly grab sampling. Dimethyl sulfide (DMS) and dimethyl disulfide (DMDS) were the primary sulfur compounds detected, and these varied considerably depending on time of day, season, location and meteorology. DMS was more prevalent in the summer months, while DMDS was more prevalent in the spring. Elevated concentrations of benzene and chloroform were found in the region during 2017, with average values of short term grab samples over three times the acceptable ambient concentrations in Idaho. These levels did not persist during longer term sampling of 12-hours, however further monitoring is needed to assess a potential health concern.

  9. Determining total sulfur content in coal by MSC radiometric sulfur meter

    Energy Technology Data Exchange (ETDEWEB)

    Czerw, B; Sikora, T; Golebiowski, W

    1976-01-01

    The MSC radiometric sulfur meter is used to determine total sulfur content in brown and black coals. Sulfur content is determined by measuring intensity of radiation beam which has travelled through a coal sample with the optimum constant surface mass. Construction of the MSC, consisting of a measuring head and the electronic measuring system, is shown in a scheme. AM-241 (with activity of 50 mCi) is the source of radiation. Energy of 25.3 keV (tin disc) is selected as the optimum. The SSU-70 probe with NaJ/Tl crystal is the radiation detector. The black coal sample weighs 10 g and the brown coal sample weighs 18 g. Duration of sulfur determination is 10 min. Error of sulfur determination ranges from plus or minus 0.2% to 0.3%. The results of operational tests of MSC radiometric sulfur meters in black and brown coal mines are discussed. Accuracy of measurement is shown in 5 tables. (8 refs.)

  10. Potential for preparation of hot gas cleanup sorbents from spent hydroprocessing catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; Biagini, M. [Canada Centre for Mineral and Energy Technology, Ottawa, ON (Canada). Energy Research Labs.

    1996-01-01

    Three spent-decoked hydroprocessing catalysts and two corresponding fresh catalysts were tested as hot gas clean-up sorbents and compared with the zinc ferrite using a simulated coal gasification gas mixture. The catalysts deposited only by coke exhibited relatively good cleaning efficiency. The catalyst deposited by coke and metals such as vanadium and nickel was less efficient. The useful life of the spent hydroprocessing catalysts may be extended if utilized as hot gas clean-up sorbents. 12 refs., 3 figs., 4 tabs.

  11. Thermodynamics of organic molecule adsorption on sorbents modified with 5-hydroxy-6-methyluracil by inverse gas chromatography.

    Science.gov (United States)

    Gus'kov, Vladimir Yu; Gainullina, Yulia Yu; Ivanov, Sergey P; Kudasheva, Florida Kh

    2014-08-22

    The thermodynamic features of organic molecule adsorption from the gaseous phase of sorbents modified with 5-hydroxy-6-methyluracil (HMU) were studied. Molar internal energy and entropy of adsorption variation analyses showed that with every type surface, except for silica gel, layers of supramolecular structure have cavities equal in size with the ones revealed in HMU crystals by X-ray diffraction. Adsorption thermodynamics on HMU-modified sorbents depended on the amount of impregnated HMU and on the polarity, but not the porosity, of the initial sorbent. Polarity of the modified surface increased as a function of HMU quantity and initial sorbent mean pore size, but become appreciably lower if the initial surface is capable of hydrogen bonding. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Sorbents for effective removal of radioactive antimony during chemical decontamination

    International Nuclear Information System (INIS)

    Nishad, Padala Abdul; Bhaskarapillai, Anupkumar; Velmurugan, Sankaralingam

    2014-01-01

    Removal of radioactive antimony is a challenging problem. Often, during decontamination, they get mobilized around the system and redeposit in different areas thus offsetting the reduction in the radiation field obtained by removing other activities such as 60 Co. Thus, there is a clear need for better antimony removing materials/strategies for effective reactor decontamination. In this regard, six commercially available sorbents namely, Tulsion A33 (strong base anion (-OH) resin), Amberlite IRC-718 (chelating resin), Radex ® Sb-1000, nano TiO 2 -special grade (Inorganic type IX), Chitosan (biosorbent) and Aeroxide p25 (nano TiO 2 , Inorganic type IX) were evaluated for their antimony sorption properties. Radex ® and TiO 2 based materials were found to be more effective in removing both Sb(V) and Sb(III). Solution pH was seen to significantly influence the antimony sorption and the effect was more prominent in anion resin, when tested under column conditions. Apart from the commercial sorbents, we have synthesised a robust high performing sorbent (TA-Chitosan beads) in the form of stable beads, using nano-TiO 2 and chitosan. The beads were found to retain the antimony sorption properties of the nano-TiO 2 , while adapting a physical format suitable for large scale operations. The sorbent exhibited almost complete sorption of antimony both in low (ppb level) as well as high concentrations of antimony. The suitability of the beads for use in column mode has been established and its radiation stability was probed in detail. The beads were found to be stable to irradiations as ascertained from the TOC values and unchanged sorption properties. The sorption properties of the CHITA beads in typical decontamination formulation containing mixture of complexing agents have been investigated in detail. (author)

  13. A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent

    International Nuclear Information System (INIS)

    Waysbort, Daniel; McGarvey, David J.; Creasy, William R.; Morrissey, Kevin M.; Hendrickson, David M.; Durst, H. Dupont

    2009-01-01

    A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Green TM , has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO 4 -2 ) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t 1/2 ≤ 4 min), 1:10 for HD (t 1/2 1/2 < 2 min). The vapor concentrations of GD above the dry sorbent and the sorbent with decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD

  14. Strategic Design and Optimization of Inorganic Sorbents for Cesium, Strontium and Actinides

    International Nuclear Information System (INIS)

    Maginn, Edward J.

    2009-01-01

    The primary objective of the Notre Dame component of the project was computational in nature. The goal was to provide a design tool for the synthesis of optimized sorbents for the removal of cesium, strontium and actinides from nuclear waste solutions. Molecular modeling enables us to observe and better understand the molecular level interactions that govern the selectivity of specific radionuclides in a particular sorbent. The research focused on the development and validation of a suitable and transferable model for all the cations and ion exchangers of interest, nd then subsequent simulations which determined the siting and mobility of water and cations. Speciic accomplishments include: (1) improving existing intermolecular force fields to accurately model the sorbents of interest; (2) utilizing energy-minimizations and molecular dynamics simulations for structural prediction of CST and niobium-substituted CST materials; (3) determining Na+/water positions in polyoxoniobate materials using molecular dynamics simulations; and (4) developing Hybrid Monte Carlo methods for improved structural prediction.

  15. Colloid stable sorbents for cesium removal: Preparation and application of latex particles functionalized with transition metals ferrocyanides

    Energy Technology Data Exchange (ETDEWEB)

    Avramenko, Valentin [Institute of Chemistry, Far Eastern Branch, Russian Academy of Sciences, 159 ave 100-letiya Vladivostoka, Vladivostok 690022 (Russian Federation); Bratskaya, Svetlana, E-mail: sbratska@ich.dvo.ru [Institute of Chemistry, Far Eastern Branch, Russian Academy of Sciences, 159 ave 100-letiya Vladivostoka, Vladivostok 690022 (Russian Federation); Zheleznov, Veniamin; Sheveleva, Irina [Institute of Chemistry, Far Eastern Branch, Russian Academy of Sciences, 159 ave 100-letiya Vladivostoka, Vladivostok 690022 (Russian Federation); Voitenko, Oleg [Far Eastern Federal University, Laboratory of Electron Microscopy and Image Processing, 27, Oktyabr' skaya Street, Vladivostok 690950 (Russian Federation); Sergienko, Valentin [Institute of Chemistry, Far Eastern Branch, Russian Academy of Sciences, 159 ave 100-letiya Vladivostoka, Vladivostok 690022 (Russian Federation)

    2011-02-28

    In this paper we suggest a principally new approach to preparation of colloid stable selective sorbents for cesium uptake using immobilization of transition metals (cobalt, nickel, and copper) ferrocyanides in nanosized carboxylic latex emulsions. The effects of ferrocyanide composition, pH, and media salinity on the sorption properties of the colloid stable sorbents toward cesium ions were studied in solutions containing up to 200 g/L of sodium nitrate or potassium chloride. The sorption capacities of the colloid sorbents based on mixed potassium/transition metals ferrocyanides were in the range 1.3-1.5 mol Cs/mol ferrocyanide with the highest value found for the copper ferrocyanide. It was shown that the obtained colloid-stable sorbents were capable to penetrate through bulk materials without filtration that made them applicable for decontamination of solids, e.g. soils, zeolites, spent ion-exchange resins contaminated with cesium radionuclides. After decontamination of liquid or solid radioactive wastes the colloid-stable sorbents can be easily separated from solutions by precipitation with cationic flocculants providing localization of radionuclides in a small volume of the precipitates formed.

  16. Ecologically friendly ways to clean up oil spills in harbor water areas: crude oil and diesel sorption behavior of natural sorbents.

    Science.gov (United States)

    Paulauskiene, Tatjana

    2018-04-01

    This work aimed to evaluate the sorption capacity of natural sorbents (wool, moss, straw, peat) and their composites during the sorption of crude oil and of diesel overspread on the water surface. The work presents the research results of the maximum sorption capacity of the sorbents/their composites using crude oil/diesel; the sorption capacity of the sorbents/their composites when crude oil/diesel is spilled on the water surface; and the research results of the unrealized part of the crude oil/diesel in the sorbents. The results of the analysis showed that all the sorbents and their composites have their selectivity to crude oil less than 50%. Also the results showed that the distribution of diesel and water in the sorbents and their composites is very different compared with the distribution of crude oil during the sorption analyses. In total, the diesel in the liquid mass absorbed by the straw and the peat amounted to 17 and 20%, respectively. This shows that these sorbents are much more selective for water but not for diesel. A larger part of the diesel was in the liquid amount absorbed by the composites-up to 33%. Accordingly, the use of these composites in watery environments is much more effective than the use of individual sorbents. The composition of sorbents in the composite enhanced both the hydrophobic and the oleophilic properties; as a result, a more effective removal of the diesel and oil from the water surface was achieved.

  17. Investigation on gasoline deep desulfurisation for fuel cell applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, J.C.; Song, L.F.; Hu, J.Y.; Ong, S.L.; Ng, W.J.; Lee, L.Y. [National University of Singapore (Singapore). Dept. of Civil Engineering; Wang, Y.H.; Zhao, J.G.; Ma, R.Y. [Beijing University of Chemical Technology (China). Ministry of Education

    2005-01-01

    The effect of adding some amounts of cerium into Zn-Fe-O/Al{sub 2}O{sub 3} sorbent on its performance of removal of organic sulfur compounds from gasoline by adsorption was studied in this paper. It showed that the ideal compositions for the preparation of Zn-Fe-Ce-O/Al{sub 2}O{sub 3} consisted of 4.54 wt.% ZnO, 2.25 wt.% Fe{sub 2}O{sub 3} and 2.5 wt.% CeO{sub 2}, respectively, shortened as AZFCO{sub 0.52} Further study indicated that this sorbent could be well regenerated at 250{sup o}C with gas mixtures containing 6.0 vol.% steam + air and 2400 ml h{sup -1} ml {sup -1} gas space velocity. At those regenerated conditions and 60{sup o}C adsorption temperature, the AZFCO{sub 0.52} sorbent had better desulfurization stability, which was confirmed by typical characterization results using BET, XRD and SEM apparatus. This implied that the AZFCO{sub 0.52} sorbent could be an ideal sorbent for removal of organic sulfur compounds from gasoline. (author)

  18. Genomic Insights into the Sulfur Metabolism of Phototrophic Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Bryant, Donald A.

    2008-01-01

    Green sulfur bacteria (GSB) utilize various combinations of sulfide, elemental sulfur, thiosulfate, ferrous iron, and hydrogen for anaerobic photoautotrophic growth. Genome sequence data is currently available for 12 strains of GSB. We present here a genome-based survey of the distribution...... and phylogenies of genes involved in oxidation of sulfur compounds in these strains. Sulfide:quinone reductase, encoded by sqr, is the only known sulfur-oxidizing enzyme found in all strains. All sulfide-utilizing strains contain the dissimilatory sulfite reductase dsrABCEFHLNMKJOPT genes, which appear...... to be involved in elemental sulfur utilization. All thiosulfate-utilizing strains have an identical sox gene cluster (soxJXYZAKBW). The soxCD genes found in certain other thiosulfate-utilizing organisms like Paracoccus pantotrophus are absent from GSB. Genes encoding flavocytochrome c (fccAB), adenosine-5...

  19. Capital cost: high and low sulfur coal plants-1200 MWe. [High sulfur coal

    Energy Technology Data Exchange (ETDEWEB)

    1977-01-01

    This Commercial Electric Power Cost Study for 1200 MWe (Nominal) high and low sulfur coal plants consists of three volumes. The high sulfur coal plant is described in Volumes I and II, while Volume III describes the low sulfur coal plant. The design basis and cost estimate for the 1232 MWe high sulfur coal plant is presented in Volume I, and the drawings, equipment list and site description are contained in Volume II. The reference design includes a lime flue gas desulfurization system. A regenerative sulfur dioxide removal system using magnesium oxide is also presented as an alternate in Section 7 Volume II. The design basis, drawings and summary cost estimate for a 1243 MWe low sulfur coal plant are presented in Volume III. This information was developed by redesigning the high sulfur coal plant for burning low sulfur sub-bituminous coal. These coal plants utilize a mechanical draft (wet) cooling tower system for condenser heat removal. Costs of alternate cooling systems are provided in Report No. 7 in this series of studies of costs of commercial electrical power plants.

  20. Immobilized humic substances and immobilized aggregates of humic substances as sorbent for solid phase extraction.

    Science.gov (United States)

    Erny, Guillaume L; Gonçalves, Bruna M; Esteves, Valdemar I

    2013-09-06

    In this work, humic substances (HS) immobilized, as a thin layer or as aggregates, on silica gel were tested as material for solid phase extraction. Some triazines (simazine, atrazine, therbutylazine, atrazine-desethyl-desisopropyl-2-hydroxy, ametryn and terbutryn), have been selected as test analytes due to their environmental importance and to span a large range of solubility and octanol/water partition coefficient (logP). The sorbent was obtained immobilizing a thin layer of HS via physisorption on a pre-coated silica gel with a cationic polymer (polybrene). While the sorbent could be used as it is, it was demonstrated that additional HS could be immobilized, via weak interactions, to form stable humic aggregates. However, while a higher quantity of HS could be immobilized, no significant differences were observed in the sorption parameters. This sorbent have been tested for solid phase extraction to concentrate triazines from aqueous matrixes. The sorbent demonstrated performances equivalent to commercial alternatives as a concentration factor between 50 and 200, depending on the type of triazines, was obtained. Moreover the low cost and the high flow rate of sample through the column allowed using high quantity of sorbent. The analytical procedure was tested with different matrixes including tap water, river water and estuarine water. Copyright © 2013 Elsevier B.V. All rights reserved.

  1. Evaluation of Solid Sorbents As A Retrofit Technology for CO{sub 2} Capture from Coal-Fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Krutka, Holly; Sjostrom, Sharon

    2011-07-31

    Through a U.S. Department of Energy (DOE) National Energy Technology Laboratory (NETL) funded cooperative agreement DE-NT0005649, ADA Environmental Solutions (ADA) has begun evaluating the use of solid sorbents for CO{sub 2} capture. The project objective was to address the viability and accelerate development of a solid-based CO{sub 2} capture technology. To meet this objective, initial evaluations of sorbents and the process / equipment were completed. First the sorbents were evaluated using a temperature swing adsorption process at the laboratory scale in a fixed-bed apparatus. A slipstream reactor designed to treat flue gas produced by coal-fired generation of nominally 1 kWe was designed and constructed, which was used to evaluate the most promising materials on a more meaningful scale using actual flue gas. In a concurrent effort, commercial-scale processes and equipment options were also evaluated for their applicability to sorbent-based CO{sub 2} capture. A cost analysis was completed that can be used to direct future technology development efforts. ADA completed an extensive sorbent screening program funded primarily through this project, DOE NETL cooperative agreement DE-NT0005649, with support from the Electric Power Research Institute (EPRI) and other industry participants. Laboratory screening tests were completed on simulated and actual flue gas using simulated flue gas and an automated fixed bed system. The following types and quantities of sorbents were evaluated: 87 supported amines, 31 carbon based materials, 6 zeolites, 7 supported carbonates (evaluated under separate funding), 10 hydrotalcites. Sorbent evaluations were conducted to characterize materials and down-select promising candidates for further testing at the slipstream scale. More than half of the materials evaluated during this program were supported amines. Based on the laboratory screening four supported amine sorbents were selected for evaluation at the 1 kW scale at two different

  2. Characterization of desulfurization, denitrogenation and process sulfur transfer during hydropyrolysis of Chinese high sulfur coals

    Energy Technology Data Exchange (ETDEWEB)

    Sun Chenggong; Li Baoqing [Chinese Academy of Sciences, Taiyuan (China). State Key Lab. of Coal Conversion; Snape, C.E. [Strathclyde Univ., Glasgow (United Kingdom). Dept. of Pure and Applied Chemistry

    1997-12-31

    The process desulphurization and denitrogenation of Chinese high sulfur coals and the characteristics of sulfur transformation during non-catalytic hydropyrolysis were investigated by a 10 g fixed-bed reactor and a small-scaled reactor with online spectrometry respectively. It was indicated that more than 70% of the total sulfur of the two high sulfur coals and almost all pyritic sulfur are removed as H{sub 2}S, leaving the char and tar products with much less sulfur distribution. The liability of sulfur transformation to tar products is closely related to the thiophenic structure forms rather than sulfidic forms. At the same time, the formation of trace amount of sulfur dioxide indicates the presence of inherent sulfur oxidation reactions inside coal frame structures even under H{sub 2} pressure. (orig.)

  3. Sulfation diffusion model for SO{sub 2} capture on the T-T sorbent at moderate temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Li, Y.R.; Yang, L.Z.; You, C.F.; Qi, H.Y. [Tsinghua University, Beijing (China)

    2009-07-15

    A sulfation model was developed for dry flue gas desulfurization (FGD) at moderate temperatures to describe the reaction characteristics of the T-T sorbent clusters and the fine CaO particles that fall off the sorbent grains in a circulating fluidized bed (CFB) reactor. The cluster model describes the calcium conversion and reaction rate for various size sorbent clusters. The sulfation reaction is first order with respect to the SO{sub 2} concentration above 973 K. The calcium conversion and reaction rate for the CaO particles were obtained by extrapolation. In the model for CaO particle, the reaction rate is linearly related to the calcium conversion and the SO{sub 2} concentration in the rapid reaction stage and linearly related only with the calcium conversion after the product layer forms. The sulfation model accurately describes the sulfation of the T-T sorbent flowing through a CFB reactor.

  4. PROTOTYPE SCALE TESTING OF LIMB TECHNOLOGY FOR A PULVERIZED-COAL-FIRED BOILER

    Science.gov (United States)

    The report summarizes results of an evaluation of furnace sorbent injection (FSI) to control sulfur dioxide (SO2) emissions from coal-fired utility boilers. (NOTE: FSI of calcium-based sorbents has shown promise as a moderate SO2 removal technology.) The Electric Power Research I...

  5. High temperature capture of CO2 on lithium-based sorbents from rice husk ash.

    Science.gov (United States)

    Wang, Ke; Guo, Xin; Zhao, Pengfei; Wang, Fanzi; Zheng, Chuguang

    2011-05-15

    Highly efficient Li(4)SiO(4) (lithium orthosilicate)-based sorbents for CO(2) capture at high temperature, was developed using waste materials (rice husk ash). Two treated rice husk ash (RHA) samples (RHA1 and RHA2) were prepared and calcined at 800°C in the presence of Li(2)CO(3). Pure Li(4)SiO(4) and RHA-based sorbents were characterized by X-ray fluorescence, X-ray diffraction, scanning electron microscopy, nitrogen adsorption, and thermogravimetry. CO(2) sorption was tested through 15 carbonation/calcination cycles in a fixed bed reactor. The metals of RHA were doped with Li(4)SiO(4) resulting to inhibited growth of the particles and increased pore volume and surface area. Thermal analyses indicated a much better CO(2) absorption in Li(4)SiO(4)-based sorbent prepared from RHA1 (higher metal content sample) because the activation energies for the chemisorption process and diffusion process were smaller than that of pure Li(4)SiO(4). RHA1-based sorbent also maintained higher capacities during the multiple cycles. Copyright © 2011 Elsevier B.V. All rights reserved.

  6. Sulfur polymer cement, a new stabilization agent for mixed and low- level radioactive waste

    International Nuclear Information System (INIS)

    Darnell, G.R.

    1991-01-01

    Solidification and stabilization agents for radioactive, hazardous, and mixed wastes are failing to pass governmental tests at alarming rates. The Department of Energy's National Low-Level Waste Management Program funded testing of Sulfur Polymer Cement (SPC) by Brookhaven National Laboratory during the 1980s. Those tests and tests by the US Bureau of Mines (the original developer of SPC), universities, states, and the concrete industry have shown SPC to be superior to hydraulic cements in most cases. Superior in what wastes can be successfully combined and in the quantity of waste that can be combined and still pass the tests established by the US Environmental Protection Agency and the US Nuclear Regulatory Commission

  7. The cleaning of the soils polluted by oil and radionuclides by natural sorbents

    International Nuclear Information System (INIS)

    Farajov, M.F.; Shamilov, E.N.; Abdullayev, A.S.; Huseynov, V.I.

    2005-01-01

    Full text : Problem of environmental pollution in oil extracting areas of Absheron peninsula became the very important discussion object lately. It this areas for many years oil and well waters were flowed to environmental areas caused a lot of pools in that areas and at the result the soil and plants were polluted with oil and radionuclides. By last years researches it was revealed that amount of radium 226 oil well water contains 10 - 500 Bq/l. Sometimes amount of radium 226 in polluted soils is increasing to 2000--5000 Bq/l and at the result it is raising probability of entering radionuclides by the way of migration from ground to plants into the nutrition chain cycle. Thus the polluted areas with oil and radionuclides and also when oil spills from oil-pipes by an accident the deactivation of soils is one of the main and most actual problems. In researches for cleaning of polluted soils with radionuclides for the first time were used the phyto sorbent modified breccias forms taken from Chaildag, Gobu, and Lokbatan mud volcano areas. The mineral contain of volcano mud generally consists of clay rocks -(kaolinit, montmorillonit, zeolite, chlorite, biotit) pyrite, and i.e.[2]. The polluted soil samples were taken in Surakhani region from area with the 150 mikroroentgen per hour radiation background. The contain and amount of radionuclides were determined with the radio spectrometer P rogress - Beta - Gamma . Polluted soil samples firstly are washed by hot water and HCl solution by mixing for 3-5 hours. At the next level by adding pieced sorbent into the solution is intensively mixing by mixer and putting for sedimentation for 24 hours. After sedimentation the stiring process is repeated by adding HCl on the sediment again. The soil is stirred by water for last time. Decomposed solutions from soil are adhering and are maked with sorbent again. Thus the soil is quite cleaned from oil and radionuclides by the sorbents we offer. At the same time this sorbents may be

  8. Strong Capillarity, Chemisorption, and Electrocatalytic Capability of Crisscrossed Nanostraws Enabled Flexible, High-Rate, and Long-Cycling Lithium-Sulfur Batteries.

    Science.gov (United States)

    Ma, Lianbo; Zhang, Wenjun; Wang, Lei; Hu, Yi; Zhu, Guoyin; Wang, Yanrong; Chen, Renpeng; Chen, Tao; Tie, Zuoxiu; Liu, Jie; Jin, Zhong

    2018-05-22

    The development of flexible lithium-sulfur (Li-S) batteries with high energy density and long cycling life are very appealing for the emerging flexible, portable, and wearable electronics. However, the progress on flexible Li-S batteries was limited by the poor flexibility and serious performance decay of existing sulfur composite cathodes. Herein, we report a freestanding and highly flexible sulfur host that can simultaneously meet the flexibility, stability, and capacity requirements of flexible Li-S batteries. The host consists of a crisscrossed network of carbon nanotubes reinforced CoS nanostraws (CNTs/CoS-NSs). The CNTs/CoS-NSs with large inner space and high conductivity enable high loading and efficient utilization of sulfur. The strong capillarity effect and chemisorption of CNTs/CoS-NSs to sulfur species were verified, which can efficiently suppress the shuttle effect and promote the redox kinetics of polysulfides. The sulfur-encapsulated CNTs/CoS-NSs (S@CNTs/CoS-NSs) cathode in Li-S batteries exhibits superior performance, including high discharge capacity, rate capability (1045 mAh g -1 at 0.5 C and 573 mAh g -1 at 5.0 C), and cycling stability. Intriguingly, the soft-packed Li-S batteries based on S@CNTs/CoS-NSs cathode show good flexibility and stability upon bending.

  9. A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent

    Energy Technology Data Exchange (ETDEWEB)

    Waysbort, Daniel [Israel Institute for Biological Research, PO Box 19, Ness-Ziona 74100 (Israel); McGarvey, David J. [R and T Directorate, Edgewood Chemical and Biological Center (ECBC), Aberdeen Proving Ground-Edgewood Area, MD 21010 (United States)], E-mail: david.mcgarvey@us.army.mil; Creasy, William R.; Morrissey, Kevin M.; Hendrickson, David M. [SAIC, P.O. Box 68, Gunpowder Branch, Aberdeen Proving Ground, MD 21010 (United States); Durst, H. Dupont [R and T Directorate, Edgewood Chemical and Biological Center (ECBC), Aberdeen Proving Ground-Edgewood Area, MD 21010 (United States)

    2009-01-30

    A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Green{sup TM}, has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO{sub 4}{sup -2}) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t{sub 1/2} {<=} 4 min), 1:10 for HD (t{sub 1/2} < 2 min with molybdate), and 1:10 for GD (t{sub 1/2} < 2 min). The vapor concentrations of GD above the dry sorbent and the sorbent with decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD.

  10. The significance of elemental sulfur dissolution in liquid electrolyte lithium sulfur batteries

    NARCIS (Netherlands)

    Harks, Peter Paul R.M.L.; Robledo, Carla B.; Verhallen, Tomas W.; Notten, Peter H.L.; Mulder, Fokko M.

    2017-01-01

    It is shown that the dissolution of elemental sulfur into, and its diffusion through, the electrolyte allows cycling of lithium–sulfur batteries in which the sulfur is initially far removed and electrically insulated from the current collector. These findings help to understand why liquid

  11. Interfacial and electrical properties of HfAlO/GaSb metal-oxide-semiconductor capacitors with sulfur passivation

    International Nuclear Information System (INIS)

    Tan Zhen; Zhao Lian-Feng; Wang Jing; Xu Jun

    2014-01-01

    Interfacial and electrical properties of HfAlO/GaSb metal-oxide-semiconductor capacitors (MOSCAPs) with sulfur passivation were investigated and the chemical mechanisms of the sulfur passivation process were carefully studied. It was shown that the sulfur passivation treatment could reduce the interface trap density D it of the HfAlO/GaSb interface by 35% and reduce the equivalent oxide thickness (EOT) from 8 nm to 4 nm. The improved properties are due to the removal of the native oxide layer, as was proven by x-ray photoelectron spectroscopy measurements and high-resolution cross-sectional transmission electron microscopy (HRXTEM) results. It was also found that GaSb-based MOSCAPs with HfAlO gate dielectrics have interfacial properties superior to those using HfO 2 or Al 2 O 3 dielectric layers. (condensed matter: electronic structure, electrical, magnetic, and optical properties)

  12. Concentration and immobilization of 137Cs from liquid radioactive waste using sorbents based on hydrated titanium and zirconium oxides

    Science.gov (United States)

    Voronina, A. V.; Noskova, A. Y.; Gritskevich, E. Y.; Mashkovtsev, M. A.; Semenishchev, V. S.

    2017-09-01

    The possibility of use of sorbents based on hydrated titanium and zirconium oxides (T-3A, T-35, NPF-HTD) for concentration and immobilization of 137Cs from liquid radioactive waste of various chemical composition (fresh water, seawater, solutions containing NaNO3, ammonium acetate, EDTA) was evaluated. It was shown that the NPF-HTD and T-35 sorbents separate 137Cs from fresh water and seawater with distribution coefficients as high as 6.2.104 and 6.1.104, 4.0.105 and 1.6.105 L kg-1 respectively; in 1 M ammonium acetate these values were 2.0.103 and 1.0.103 L kg-1. The NPF-HTD sorbent showed the highest selectivity for cesium in NaNO3 solution: cesium distribution coefficients in 1M NaNO3 was 1.4.106 L kg-1. All studied sorbents are suitable for deactivation of solutions containing EDTA. Cesium distribution coefficients were around 102-103 L kg-1 depending on EDTA concentration. Chemical stability of the sorbents was also studied. It was shown that 137Cs leaching rate from all sorbents meet the requirements for matrix materials.

  13. LOW CONCENTRATION MERCURY SORPTION MECHANISMS AND CONTROL BY CALCIUM-BASED SORBENTS; APPLICATION IN COAL-FIRED PROCESSES

    Science.gov (United States)

    The capture of elemental mercury (Hgo) and mercuric chloride (HgCl2) by three types of calcium (Ca)-based sorbents was examined in this bench-scale study under conditions prevalent in coal fired utilities. Ca-based sorbent performances were compared to that of an activated carbon...

  14. Phosphorus removal from aqueous solution using iron coated natural and engineered sorbents

    International Nuclear Information System (INIS)

    Boujelben, N.; Bouzid, J.; Elouear, Z.; Feki, M.; Jamoussi, F.; Montiel, A.

    2008-01-01

    New filtration materials covered with metallic oxides are good adsorbents for both cation and anion forms of pollutants. Sfax is one of the most important industrial towns in Tunisia. Its phosphate manufacture in particular is causing considerable amounts of water pollution. Therefore, there is a need to find out a new way of getting rid of this excessive phosphate from water. This work is aimed to examining the potential of three sorbent materials (synthetic iron oxide coated sand (SCS), naturally iron oxide coated sand (NCS) and iron oxide coated crushed brick (CB)) for removing phosphate ions from aqueous solutions. According to our literature survey CB was not used as adsorbent previously. Phosphate ions are used here as species model for the elimination of other similar pollutants (arsenates, antimonates). Optical microscope and scanning electron microscope (SEM) analyses were used to investigate the surface properties and morphology of the coated sorbents. Infra-red spectroscopy and X-ray diffraction techniques were also used to characterize the sorbent structures. Results showed that iron coated crushed brick possess more micro pores and a higher surface area owing to its clay nature. The comparative sorption of PO 4 3- from aqueous solutions by SCS, CB and NCS was investigated by batch experiments. The estimated optimum pH of phosphate ion retention for the considered sorbents was 5. The equilibrium data were analysed using the Langmuir and Freundlich isotherms. The sorption capacities of PO 4 3- at pH 5 were 1.5 mg/g for SCS, 1.8 mg/g for CB and 0.88 mg/g for NCS. The effect of temperature on sorption phenomenon was also investigated. The results indicated that adsorption is an endothermic process for phosphate ions removal. This study demonstrates that all the considered sorbents can be used as an alternative emerging technology for water treatment without any side effect or treatment process alteration

  15. Self-assembled peptides for coating of active sulfur nanoparticles in lithium–sulfur battery

    International Nuclear Information System (INIS)

    Jewel, Yead; Yoo, Kisoo; Liu, Jin; Dutta, Prashanta

    2016-01-01

    Development of lithium–sulfur (Li–S) battery is hindered by poor cyclability due to the loss of sulfur, although Li–S battery can provide high energy density. Coating of sulfur nanoparticles can help maintain active sulfur in the cathode of Li–S battery, and hence increase the cyclability. Among myriad of coating materials, synthetic peptides are very attractive because of their spontaneous self-assembly as well as electrical conductive characteristics. In this study, we explored the use of various synthetic peptides as a coating material for sulfur nanoparticles. Atomistic simulations were carried out to identify optimal peptide structure and density for coating sulfur nanoparticles. Three different peptide models, poly-proline, poly(leucine–lysine) and poly-histidine, are selected for this study based on their peptide–peptide and peptide-sulfur interactions. Simulation results show that both poly-proline and poly(leucine–lysine) can form self-assembled coating on sulfur nanoparticles (2–20 nm) in pyrrolidinone, a commonly used solvent for cathode slurry. We also studied the structural integrity of these synthetic peptides in organic [dioxolane (DOL) and dimethoxyethane (DME)] electrolyte used in Li–S battery. Both peptides show stable structures in organic electrolyte (DOL/DME) used in Li–S battery. Furthermore, the dissolution of sulfur molecules in organic electrolyte is investigated in the absence and presence of these peptide coatings. It was found that only poly(leucine–lysine)-based peptide can most effectively suppress the sulfur loss in electrolyte, suggesting its potential applications in Li–S battery as a coating material.Graphical abstract

  16. Dual layer hollow fiber sorbents: Concept, fabrication and characterization

    KAUST Repository

    Bhandari, Dhaval; Olanrewaju, Kayode O.; Bessho, Naoki; Breedveld, Victor; Koros, William J.

    2013-01-01

    and to ensure consistent sorption capacity over repeated cycles, a dense, thin polymer barrier layer on the fiber sorbents is needed to allow only thermal interactions between the sorbate loaded layer and the thermal regeneration fluid. This paper considers

  17. Sulfur-carbon nanocomposites and their application as cathode materials in lithium-sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Liang, Chengdu; Dudney, Nancy J.; Howe, Jane Y.

    2017-08-01

    The invention is directed in a first aspect to a sulfur-carbon composite material comprising: (i) a bimodal porous carbon component containing therein a first mode of pores which are mesopores, and a second mode of pores which are micropores; and (ii) elemental sulfur contained in at least a portion of said micropores. The invention is also directed to the aforesaid sulfur-carbon composite as a layer on a current collector material; a lithium ion battery containing the sulfur-carbon composite in a cathode therein; as well as a method for preparing the sulfur-composite material.

  18. Thermally moderated hollow fiber sorbent modules in rapidly cycled pressure swing adsorption mode for hydrogen purification

    KAUST Repository

    Lively, Ryan P.; Bessho, Naoki; Bhandari, Dhaval A.; Kawajiri, Yoshiaki; Koros, William J.

    2012-01-01

    We describe thermally moderated multi-layered pseudo-monolithic hollow fiber sorbents entities, which can be packed into compact modules to provide small-footprint, efficient H2 purification/CO2 removal systems for use in on-site steam methane reformer product gas separations. Dual-layer hollow fibers are created via dry-jet, wet-quench spinning with an inner "active" core of cellulose acetate (porous binder) and zeolite NaY (69 wt% zeolite NaY) and an external sheath layer of pure cellulose acetate. The co-spun sheath layer reduces the surface porosity of the fiber and was used as a smooth coating surface for a poly(vinyl-alcohol) post-treatment, which reduced the gas permeance through the fiber sorbent by at least 7 orders of magnitude, essentially creating an impermeable sheath layer. The interstitial volume between the individual fibers was filled with a thermally-moderating paraffin wax. CO2 breakthrough experiments on the hollow fiber sorbent modules with and without paraffin wax revealed that the "passively" cooled paraffin wax module had 12.5% longer breakthrough times than the "non-isothermal" module. The latent heat of fusion/melting of the wax offsets the released latent heat of sorption/desorption of the zeolites. One-hundred rapidly cycled pressure swing adsorption cycles were performed on the "passively" cooled hollow fiber sorbents using 25 vol% CO2/75 vol% He (H2 surrogate) at 60 °C and 113 psia, resulting in a product purity of 99.2% and a product recovery of 88.1% thus achieving process conditions and product quality comparable to conventional pellet processes. Isothermal and non-isothermal dynamic modeling of the hollow fiber sorbent module and a traditional packed bed using gPROMS® indicated that the fiber sorbents have sharper fronts (232% sharper) and longer adsorbate breakthrough times (66% longer), further confirming the applicability of the new fiber sorbent approach for H2 purification. © 2012, Hydrogen Energy Publications, LLC

  19. Thermally moderated hollow fiber sorbent modules in rapidly cycled pressure swing adsorption mode for hydrogen purification

    KAUST Repository

    Lively, Ryan P.

    2012-10-01

    We describe thermally moderated multi-layered pseudo-monolithic hollow fiber sorbents entities, which can be packed into compact modules to provide small-footprint, efficient H2 purification/CO2 removal systems for use in on-site steam methane reformer product gas separations. Dual-layer hollow fibers are created via dry-jet, wet-quench spinning with an inner "active" core of cellulose acetate (porous binder) and zeolite NaY (69 wt% zeolite NaY) and an external sheath layer of pure cellulose acetate. The co-spun sheath layer reduces the surface porosity of the fiber and was used as a smooth coating surface for a poly(vinyl-alcohol) post-treatment, which reduced the gas permeance through the fiber sorbent by at least 7 orders of magnitude, essentially creating an impermeable sheath layer. The interstitial volume between the individual fibers was filled with a thermally-moderating paraffin wax. CO2 breakthrough experiments on the hollow fiber sorbent modules with and without paraffin wax revealed that the "passively" cooled paraffin wax module had 12.5% longer breakthrough times than the "non-isothermal" module. The latent heat of fusion/melting of the wax offsets the released latent heat of sorption/desorption of the zeolites. One-hundred rapidly cycled pressure swing adsorption cycles were performed on the "passively" cooled hollow fiber sorbents using 25 vol% CO2/75 vol% He (H2 surrogate) at 60 °C and 113 psia, resulting in a product purity of 99.2% and a product recovery of 88.1% thus achieving process conditions and product quality comparable to conventional pellet processes. Isothermal and non-isothermal dynamic modeling of the hollow fiber sorbent module and a traditional packed bed using gPROMS® indicated that the fiber sorbents have sharper fronts (232% sharper) and longer adsorbate breakthrough times (66% longer), further confirming the applicability of the new fiber sorbent approach for H2 purification. © 2012, Hydrogen Energy Publications, LLC

  20. Sulfurized carbon: a class of cathode materials for high performance lithium/sulfur batteries

    Directory of Open Access Journals (Sweden)

    Sheng S. Zhang

    2013-12-01

    Full Text Available Liquid electrolyte lithium/sulfur (Li/S batteries cannot come into practical applications because of many problems such as low energy efficiency, short cycle life, and fast self-discharge. All these problems are related to the dissolution of lithium polysulfide, a series of sulfur reduction intermediates, in the liquid electrolyte, and resulting parasitic reactions with the Li anode. Covalently binding sulfur onto carbon surface is a solution to completely eliminate the dissolution of lithium polysulfide and make the Li/S battery viable for practical applications. This can be achieved by replacing elemental sulfur with sulfurized carbon as the cathode material. This article reviews the current efforts on this subject and discusses the syntheses, electrochemical properties, and prospects of the sulfurized carbon as a cathode material in the rechargeable Li/S batteries.

  1. CO_2 capture with solid sorbent: CFD model of an innovative reactor concept

    International Nuclear Information System (INIS)

    Barelli, L.; Bidini, G.; Gallorini, F.

    2016-01-01

    Highlights: • A new reactor solution based on rotating fixed beds was presented. • The preliminary design of the reactor was approached. • A CFD model of the reactor, including CO_2 capture kinetic, was developed. • The CFD model is validated with experimental results. • Sorbent exploitation increasing is possible thanks to the new reactor. - Abstract: In future decarbonization scenarios, CCS with particular reference to post-combustion technologies will be an important option also for energy intensive industries. Nevertheless, today CCS systems are rarely installed due to high energy and cost penalties of current technology based on chemical scrubbing with amine solvent. Therefore, innovative solutions based on new/optimized solvents, sorbents, membranes and new process designs, are R&D priorities. Regarding the CO_2 capture through solid sorbents, a new reactor solution based on rotating fixed beds is presented in this paper. In order to design the innovative system, a suitable CFD model was developed considering also the kinetic capture process. The model was validated with experimental results obtained by the authors in previous research activities, showing a potential reduction of energy penalties respect to current technologies. In the future, the model will be used to identify the control logic of the innovative reactor in order to verify improvements in terms of sorbent exploitation and reduction of system energy consumption.

  2. Effect of different sulfur levels from various sources on brassica napus growth and soil sulfur fractions

    International Nuclear Information System (INIS)

    Khalid, R.; Khan, K.S.; Islam, M.; Yousaf, M.; Shabbir, G.

    2012-01-01

    A two year field study was conducted at two different locations in northern rain fed Punjab, Pakistan to assess the effect of different rates of sulfur application from various sources on soil sulfur fractions and growth of Brassica napus. The treatments included three sulfur sources i. e., single super phosphate, ammonium sulfate and gypsum each applied at five different rates (0, 10, 20, 30 and 40 kg S ha/sup -1/ ). Sulfur application had a significant positive effect on the growth and yield parameters of Brassica napus. Among the sulfur sources ammonium sulfate resulted in maximum increase in plant growth and yield parameters, followed by single super phosphate. Sulfur content and uptake by crop plants was significantly higher with ammonium sulfate application as compared to other two sulfur sources. Sulfur application also exerted a significant positive effect on different S fractions in the soils. On an average, 18.0% of the applied sulfur got incorporated into CaCl/sub 2/ extractable sulfur fraction, while 15.6% and 35.5% entered into adsorbed and organic sulfur fractions in the soils, respectively. The value cost ratio increased significantly by sulfur application up to 30 kg ha/sup -1/. Among sulfur sources, ammonium sulfate performed best giving the highest net return. (author)

  3. Sulfur nanocrystals anchored graphene composite with highly improved electrochemical performance for lithium-sulfur batteries

    Science.gov (United States)

    Zhang, Jun; Dong, Zimin; Wang, Xiuli; Zhao, Xuyang; Tu, Jiangping; Su, Qingmei; Du, Gaohui

    2014-12-01

    Two kinds of graphene-sulfur composites with 50 wt% of sulfur are prepared using hydrothermal method and thermal mixing, respectively. Transmission Electron Microscopy (TEM) and Energy Dispersive X-ray Spectra mapping show that sulfur nanocrystals with size of ∼5 nm dispersed on graphene sheets homogeneously for the sample prepared by hydrothermal method (NanoS@G). While for the thermal mixed graphene-sulfur composite (S-G mixture), sulfur shows larger and uneven size (50-200 nm). X-ray Photoelectron Spectra (XPS) reveals the strong chemical bonding between the sulfur nanocrystals and graphene. Comparing with the S-G mixture, the NanoS@G composite shows highly improved electrochemical performance as cathode for lithium-sulfur (Li-S) battery. The NanoS@G composite delivers an initial capacity of 1400 mAh g-1 with the sulfur utilization of 83.7% at a current density of 335 mA g-1. The capacity keeps above 720 mAh g-1 over 100 cycles. The strong adherence of the sulfur nanocrystals on graphene immobilizes sulfur and polysulfides species and suppressed the "shuttle effect", resulting higher coulombic efficiency and better capacity retention. Electrochemical impedance also suggests that the strong bonding enabled rapid electronic/ionic transport and improved electrochemical kinetics, therefore good rate capability is obtained. These results demonstrate that the NanoS@G composite is a very promising candidate for high-performance Li-S batteries.

  4. Multifunctional humate-based magnetic sorbent: Preparation, properties and sorption of Cu (II), phosphates and selected pesticides

    Czech Academy of Sciences Publication Activity Database

    Janoš, P.; Kormunda, M.; Novák, František; Životský, O.; Fuitová, J.; Pilařová, V.

    2013-01-01

    Roč. 73, č. 1 (2013), s. 46-52 ISSN 1381-5148 Grant - others:GA ČR(CZ) GAP106/12/1116 Program:GA Institutional support: RVO:60077344 Keywords : magnetic sorbent * humate-based sorbent * heavy metals * phosphate * pesticides Subject RIV: CD - Macromolecular Chemistry Impact factor: 2.822, year: 2013

  5. Research and application of inorganic selective sorbents at Mayak PA; Recherches et applications sur l'utilisation de sorbants specifiques a Mayak

    Energy Technology Data Exchange (ETDEWEB)

    Logunov, M.V.; Skobtsov, A.S.; Soldatov, B.V.; Pazdnikov, A.P.; Voroshilov, Y.A.; Rovny, S.I. [Mayak Production Association, Chelyabinsk Region (Russian Federation)

    2004-12-01

    This work has been performed in order to identify selective inorganic sorbents for caesium and strontium. Thin-layer sorbents with nickel ferrocyanide embedded in an inert matrix were found to be the best for caesium. Sorbents including non-stoichiometric manganese dioxide were selected for strontium. Bench tests have been carried out on the purification of desalted water of SNF storage-pool from {sup 137}Cs, and on the purification of contaminated natural water from {sup 90}Sr. The facility for synthesizing the ferrocyanide sorbent with the registered mark 'Seleks-CFN' has been brought into operation. The sorbent ISM-S seems promising for {sup 90}Sr decontamination. (authors)

  6. Nanosilica supported CaO: A regenerable and mechanically hard CO2 sorbent at Ca-looping conditions

    International Nuclear Information System (INIS)

    Sanchez-Jimenez, P.E.; Perez-Maqueda, L.A.; Valverde, J.M.

    2014-01-01

    Highlights: • A synthetic CO 2 sorbent is prepared by impregnation of calcium nitrate on a nanosilica matrix. • Sintering of the nascent CaO in the calcination stage of carbonation/calcination cycles is hindered. • CaO conversion reaches a stable value well above the residual conversion of natural limestone. • Particle fragmentation as caused by ultrasonic irradiation in a liquid dispersion is hindered. - Abstract: This work presents a CO 2 sorbent that may be synthesized from low-cost and widely available materials following a simple method basically consisting of impregnation of a nanostructured silica support with a saturated solution of calcium nitrate. In a first impregnation stage, the use of a stoichiometric CaO/SiO 2 ratio serves to produce a calcium silicate matrix after calcination. This calcium silicate matrix acts as a thermally stable and mechanically hard support for CaO deposited on it by further impregnation. The CaO-impregnated sorbent exhibits a stable CaO conversion at Ca-looping conditions whose value depends on the CaO wt% deposited on the calcium silicate matrix, which can be increased by successive reimpregnations. A 10 wt% CaO impregnated sorbent reaches a stable conversion above 0.6 whereas the stable conversion of a 30 wt% CaO impregnated sorbent is around 0.3, which is much larger than the residual conversion of CaO derived from natural limestone (between 0.07 and 0.08). Moreover, particle size distribution measurements of samples predispersed in a liquid and subjected to high energy ultrasonic waves indicate that the CaO-impregnated sorbent has a relatively high mechanical strength as compared to limestone derived CaO

  7. Laboratory study on the high-temperature capture of HCl gas by dry-injection of calcium-based sorbents.

    Science.gov (United States)

    Shemwell, B; Levendis, Y A; Simons, G A

    2001-01-01

    This is a laboratory study on the reduction of combustion-generated hydrochloric acid (HCl) emissions by in-furnace dry-injection of calcium-based sorbents. HCl is a hazardous gaseous pollutant emitted in significant quantities by municipal and hazardous waste incinerators, coal-fired power plants, and other industrial furnaces. Experiments were conducted in a laboratory furnace at gas temperatures of 600-1000 degrees C. HCl gas diluted with N2, and sorbent powders fluidized in a stream of air were introduced into the furnace concurrently. Chlorination of the sorbents occurred in the hot zone of the furnace at gas residence times approximately 1 s. The sorbents chosen for these experiments were calcium formate (CF), calcium magnesium acetate (CMA), calcium propionate (CP), calcium oxide (CX), and calcium carbonate (CC). Upon release of organic volatiles, sorbents calcine to CaO at approximately 700 degrees C, and react with the HCl according to the reaction CaO + 2HCl CaCl2 + H2O. At the lowest temperature case examined herein, 600 degrees C, direct reaction of HCl with CaCO3 may also be expected. The effectiveness of the sorbents to capture HCl was interpreted using the "pore tree" mathematical model for heterogeneous diffusion reactions. Results show that the thin-walled, highly porous cenospheres formed from the pyrolysis and calcination of CF, CMA, and CP exhibited high relative calcium utilization at the upper temperatures of this study. Relative utilizations under these conditions reached 80%. The less costly low-porosity sorbents, calcium carbonate and calcium oxide also performed well. Calcium carbonate reached a relative utilization of 54% in the mid-temperature range, while the calcium oxide reached an 80% relative utilization at the lowest temperature examined. The data matched theoretical predictions of sorbent utilization using the mathematical model, with activation energy and pre-exponential factors for the calcination reaction of 17,000 K and 300

  8. Adsorption of Carbon Dioxide, Ammonia, Formaldehyde, and Water Vapor on Regenerable Carbon Sorbents

    Science.gov (United States)

    Wojtowicz, Marek A.; Cosgrove, Joseph E.; Serio, Michael A.; Wilburn, Monique

    2015-01-01

    Results are presented on the development of reversible sorbents for the combined carbon dioxide, moisture, and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The currently available life support systems use separate units for carbon dioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Furthermore, the current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is nonregenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. In this study, several carbon sorbents were fabricated and tested for simultaneous carbon dioxide, ammonia, formaldehyde, and water sorption. Multiple adsorption/vacuum-regeneration cycles were demonstrated at room temperature, and also the enhancement of formaldehyde sorption by the presence of ammonia in the gas mixture.

  9. Recovery of Lithium from Geothermal Brine with Lithium-Aluminum Layered Double Hydroxide Chloride Sorbents.

    Science.gov (United States)

    Paranthaman, Mariappan Parans; Li, Ling; Luo, Jiaqi; Hoke, Thomas; Ucar, Huseyin; Moyer, Bruce A; Harrison, Stephen

    2017-11-21

    We report a three-stage bench-scale column extraction process to selectively extract lithium chloride from geothermal brine. The goal of this research is to develop materials and processing technologies to improve the economics of lithium extraction and production from naturally occurring geothermal and other brines for energy storage applications. A novel sorbent, lithium aluminum layered double hydroxide chloride (LDH), is synthesized and characterized with X-ray powder diffraction, scanning electron microscopy, inductively coupled plasma optical emission spectrometry (ICP-OES), and thermogravimetric analysis. Each cycle of the column extraction process consists of three steps: (1) loading the sorbent with lithium chloride from brine; (2) intermediate washing to remove unwanted ions; (3) final washing for unloading the lithium chloride ions. Our experimental analysis of eluate vs feed concentrations of Li and competing ions demonstrates that our optimized sorbents can achieve a recovery efficiency of ∼91% and possess excellent Li apparent selectivity of 47.8 compared to Na ions and 212 compared to K ions, respectively in the brine. The present work demonstrates that LDH is an effective sorbent for selective extraction of lithium from brines, thus offering the possibility of effective application of lithium salts in lithium-ion batteries leading to a fundamental shift in the lithium supply chain.

  10. Possibilities of analyzing dump and sewage gas, and determination of halogen and sulfur compounds

    Energy Technology Data Exchange (ETDEWEB)

    Eisenmann, R

    1985-01-01

    In connection with the utilization of refuse and sewage gas efficacions analytical methods are gaining increasing importance especially with regard to halogen and sulfur compounds. The paper describes various possibilities to determine those substances. Besides gas chromatography it takes into account classic analytical methods which can be superior in biogas analytics to modern physical processes. The advantages and disadvantages of each method are discussed and practical experiences obtained by their application reported.

  11. Biological – chemical regeneration of desulphurization sorbents based on zinc ferrite

    Directory of Open Access Journals (Sweden)

    Šepelák Vladimír

    2002-03-01

    Full Text Available One of the main sources of air pollution is the combustion of fuels by various thermal and power plants, transport facilities, and metallurgical plants. Main components of industrial gases that pollute air are carbon oxides, nitrogen oxides, sulphur oxides and hydrogen sulphide. Sulphur has received a more attention than any other contaminant, because the sulphur released into the atmosphere in the form of sulphur dioxide or hydrogen sulphide is a precursor of the “acid rain” formation. To meet environmental emission regulations, sulphur and other contaminant species released during the gasification of coal must be removed from the fuel gas stream. The removal of contaminat at high temperatures is referred to as hot-gas cleanup in general and hot-gas desulphurization in particular when sulphur species are the primary contaminants to be remove. In recent years, zinc ferrite is the leading candidate for hot-gas desulphurization, capable of removing sulphur-containing species from coal gas at gasifier exit temperatures. It can also be of being regenerated for a continuous use. The conventional methods of the regeneration of sulphurized sorbents are based on oxidizing pyrolysis of sulphides or on the pressure leaching of sulphides in the water environment at high temperatures. The first results of the experiments using the biological-chemical leaching, as a new way of regeneration of sulphurized sorbent based on zinc ferrite, are presented in this paper. The results show that the biological-chemical leaching leads to the removal of sulphides layers (á-ZnS, â-ZnS from the surface of the sorbent at room temperature. The biological-chemical leaching process results in the increase of the active surface area of the regenerated sorbent.

  12. Quaternary ammonium-functionalized silica sorbents for the solid-phase extraction of aromatic amines under normal phase conditions.

    Science.gov (United States)

    Vidal, Lorena; Robin, Orlane; Parshintsev, Jevgeni; Mikkola, Jyri-Pekka; Riekkola, Marja-Liisa

    2013-04-12

    Quaternary ammonium-functionalized silica materials were synthesized and applied for solid-phase extraction (SPE) of aromatic amines, which are classified as priority pollutants by US Environmental Protection Agency. Hexamethylenetetramine used for silica surface modification for the first time was employed as SPE sorbent under normal phase conditions. Hexaminium-functionalized silica demonstrated excellent extraction efficiencies for o-toluidine, 4-ethylaniline and quinoline (recoveries 101-107%), while for N,N-dimethylaniline and N-isopropylaniline recoveries were from low to moderate (14-46%). In addition, the suitability of 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica as SPE sorbent was tested under normal phase conditions. The recoveries achieved for the five aromatic amines ranged from 89 to 99%. The stability of the sorbent was evaluated during and after 150 extractions. Coefficients of variation between 4.5 and 10.2% proved a high stability of the synthesized sorbent. Elution was carried out using acetonitrile in the case of hexaminium-functionalized silica and water for 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent. After the extraction the analytes were separated and detected by liquid chromatography ultraviolet detection (LC-UV). The retention mechanism of the materials was primarily based on polar hydrogen bonding and π-π interactions. Comparison made with activated silica proved the quaternary ammonium-functionalized materials to offer different selectivity and better extraction efficiencies for aromatic amines. Finally, 1-alkyl-3-(propyl-3-sulfonate) imidazolium-functionalized silica sorbent was successfully tested for the extraction of wastewater and soil samples. Copyright © 2013 Elsevier B.V. All rights reserved.

  13. Co-Adsorption of Ammonia and Formaldehyde on Regenerable Carbon Sorbents for the Primary Life Support System (PLSS)

    Science.gov (United States)

    Wojtowicz, Marek A.; Cosgrove, Joseph E.; Serio, Michael A.; Wilburn, Monique S.

    2016-01-01

    Results are presented on the development of a reversible carbon sorbent for trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs), and more specifically in the Primary Life Support System (PLSS). The current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is deemed non-regenerable, while the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. Data on concurrent sorption and desorption of ammonia and formaldehyde, which are major TCs of concern, are presented in this paper. A carbon sorbent was fabricated by dry impregnation of a reticulated carbon-foam support with polyvinylidene chloride, followed by carbonization and thermal oxidation in air. Sorbent performance was tested for ammonia and formaldehyde sorption and vacuum regeneration, with and without water present in the gas stream. It was found that humidity in the gas phase enhanced ammonia-sorption capacity by a factor larger than two. Co-adsorption of ammonia and formaldehyde in the presence of water resulted in strong formaldehyde sorption (to the point that it was difficult to saturate the sorbent on the time scales used in this study). In the absence of humidity, adsorption of formaldehyde on the carbon surface was found to impair ammonia sorption in subsequent runs; in the presence of water, however, both ammonia and formaldehyde could be efficiently removed from the gas phase by the sorbent. The efficiency of vacuum regeneration could be enhanced by gentle heating to temperatures below 60 deg.

  14. Development of disposal sorbents for chloride removal from high-temperature coal-derived gases

    Energy Technology Data Exchange (ETDEWEB)

    Krishnan, G.N.; Wood, B.J.; Canizales, A. [and others

    1995-11-01

    The objective of this program is to develop alkali-based disposable sorbents capable of reducing HCl vapor concentrations to less than 1 ppmv in coal gas streams at temperatures in the range 400{degrees} to 750{degrees}C and pressures in the range 1 to 20 atm. The primary areas of focus of this program are investigation of different processes for fabricating the sorbents, testing their suitability for different reactor configurations, obtaining kinetic data for commercial reactor design, and updating the economics of the process.

  15. INFLUENCE OF SOLVENT AND SORBENT CHARACTERISTICS ON DISTRIBUTION OF PENTACHLOROPHENOL IN OCTANOL-WATER AND SOIL-WATER SYSTEMS

    Science.gov (United States)

    Sorbent and solvent characteristics influencing sorption of pentachlorophenol (PCP) were investigated. Analysis of aqueous sorption data for several sorbents over a broad pH range suggested hydrophobic sorption of neutral PCP predominates at pH 7. At pH > 7, sorption of the penta...

  16. Enteric virus removal from water by coal-based sorbents: development of low-cost water filters

    Energy Technology Data Exchange (ETDEWEB)

    Chaudhuri, M.; Sattar, S.A.

    1986-01-01

    Using poliovirus type 1 (Sabin) and dechlorinated tap water, several coal-based sorbents were tested for their capacity to remove viruses from water. The sorbents included bituminous coal from Giridih, India, pretreated/impregnated with either alum, ferric hydroxide, lime or manganese dioxide. Filtrasorb-400, commercially available active carbon, was used as a reference. In batch tests, with input virus concentration of 2.34-2.83x10/sup 6/ PFU/1 and sorbent concentration of 10 g/l, alum pretreated coal removed about 96% of the virus when pH of the water was between 6.3 and 8.9. Virus sorption was rapid and a plateau was reached in 30 min. Compared with the active carbon, alum pretreated coal exhibited greater sorption energy and about one log higher limiting poliovirus sorption capacity. Downflow column study indicated the potential of alum pretreated coal as a filter media for removing enteric viruses from water. A previous study showed this sorbent to be capable of removing enteric bacteria as well. Water filters prepared from such low-cost material may prove useful for domestic use in rural areas of India and other developing countries. 19 refs.

  17. Efficiency of Oil Removal from Real Storm Water With Different Sorbents

    Directory of Open Access Journals (Sweden)

    Aušra Mažeikienė

    2011-12-01

    Full Text Available Suspended solids and oil products are considered as the most important pollutants in storm water. Surface water flow and changes in pollutant concentration complicate conventional matching techniques and prolong the duration of technological processes; therefore, a comprehensive study on this area is necessary. For this reason, the research and analysis of three different sorbents (“FIBROIL®”, “Duck”, “Reo-dry” were performed in the laboratory. According to the results of the conducted experiment, all three sorbents have similar treatment efficiency: “FIBROIL®” – 99%, “Reo-dry” – 95%, “Duck” – 98%. Filtering rate had an influence on the effectiveness of removing petrol products (slower speed increases effectiveness.Article in Lithuanian

  18. Extractive de-sulfurization and de-ashing of high sulfur coals by oxidation with ionic liquids

    International Nuclear Information System (INIS)

    Saikia, Binoy K.; Khound, Kakoli; Baruah, Bimala P.

    2014-01-01

    Highlights: • Extractive de-sulfurization and de-ashing process for cleaning high sulfur coals. • The process removes inorganic as well as organic sulfur components from high sulfur coals. • The process has less risk to chemists and other surroundings. - Abstract: The environmental consequences of energy production from coals are well known, and are driving the development of desulfurization technologies. In this investigation, ionic liquids were examined for extractive desulfurization and de-ashing in industrially important high sulfur sub-bituminous Indian coals. The ionic liquids, namely, 1-n-butyl-3-methylimidazolium tetrafluoroborate (IL1) and 1-n-butyl 3-methylimidazolium chloride (IL2) were employed for desulfurization of a few Indian coal samples in presence of HCOOH/H 2 O 2 and V 2 O 5 . Results show the maximum removal of 50.20% of the total sulfur, 48.00% of the organic sulfur, and 70.37 wt% of the ash in this process. The ionic liquids were recovered and subsequently used for further desulfurization. FT-IR spectra reveal the transformation of organic sulfur functionalities into the sulfoxides (S=O) and sulfones (-SO 2 ) due to the oxidative reactions. The sulfate, pyrite and sulfides (aryls) signals in the near edge X-ray absorption fine structure (NEXAFS) of the oxidized coal samples showed sulfur transformation during the desulfurization process. The study demonstrates the removal of significant amount of inorganic as well as organic sulfur (aryls) components from the original high sulfur coal samples to make them cleaner

  19. Novel composite sorbent AAm/MA hydrogels containing starch and ...

    Indian Academy of Sciences (India)

    A novel polymer/clay composite sorbent based on acrylamide/maleic acid, starch and clay such as kaolin was synthesized with free radical solution polymerization by using ammonium persulfate/,,','-tetramethylethylenediamine as redox initiating pair in the presence of poly(ethylene glycol)diacrylate as a crosslinker.

  20. Conductive framework of inverse opal structure for sulfur cathode in lithium-sulfur batteries.

    Science.gov (United States)

    Jin, Lu; Huang, Xiaopeng; Zeng, Guobo; Wu, Hua; Morbidelli, Massimo

    2016-09-07

    As a promising cathode inheritor for lithium-ion batteries, the sulfur cathode exhibits very high theoretical volumetric capacity and energy density. In its practical applications, one has to solve the insulating properties of sulfur and the shuttle effect that deteriorates cycling stability. The state-of-the-art approaches are to confine sulfur in a conductive matrix. In this work, we utilize monodisperse polystyrene nanoparticles as sacrificial templates to build polypyrrole (PPy) framework of an inverse opal structure to accommodate (encapsulate) sulfur through a combined in situ polymerization and melting infiltration approach. In the design, the interconnected conductive PPy provides open channels for sulfur infiltration, improves electrical and ionic conductivity of the embedded sulfur, and reduces polysulfide dissolution in the electrolyte through physical and chemical adsorption. The flexibility of PPy and partial filling of the inverse opal structure endure possible expansion and deformation during long-term cycling. It is found that the long cycling stability of the cells using the prepared material as the cathode can be substantially improved. The result demonstrates the possibility of constructing a pure conductive polymer framework to accommodate insulate sulfur in ion battery applications.

  1. Phosphate Adsorption using Modified Iron Oxide-based Sorbents in Lake Water: Kinetics, Equilibrium, and Column Tests

    Science.gov (United States)

    Adsorption behavior of Bayoxide ® E33 (E33) and three E33-modified sorbents for the removal of phosphate from lake water was investigated in this study. E33-modified sorbents were synthesized by coating with manganese (E33/Mn) and silver (E33/AgI and E33/AgII) nanoparticles. Adso...

  2. The role of graphene-based sorbents in modern sample preparation techniques.

    Science.gov (United States)

    de Toffoli, Ana Lúcia; Maciel, Edvaldo Vasconcelos Soares; Fumes, Bruno Henrique; Lanças, Fernando Mauro

    2018-01-01

    The application of graphene-based sorbents in sample preparation techniques has increased significantly since 2011. These materials have good physicochemical properties to be used as sorbent and have shown excellent results in different sample preparation techniques. Graphene and its precursor graphene oxide have been considered to be good candidates to improve the extraction and concentration of different classes of target compounds (e.g., parabens, polycyclic aromatic hydrocarbon, pyrethroids, triazines, and so on) present in complex matrices. Its applications have been employed during the analysis of different matrices (e.g., environmental, biological and food). In this review, we highlight the most important characteristics of graphene-based material, their properties, synthesis routes, and the most important applications in both off-line and on-line sample preparation techniques. The discussion of the off-line approaches includes methods derived from conventional solid-phase extraction focusing on the miniaturized magnetic and dispersive modes. The modes of microextraction techniques called stir bar sorptive extraction, solid phase microextraction, and microextraction by packed sorbent are discussed. The on-line approaches focus on the use of graphene-based material mainly in on-line solid phase extraction, its variation called in-tube solid-phase microextraction, and on-line microdialysis systems. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  3. Importance Role of Low-Cost Sorbent Produced from rice husk in Separation of zirconium from yttrium

    International Nuclear Information System (INIS)

    Kandil, S.A.

    2013-01-01

    The agricultural waste, rice husk, was used as a precursor for the production of low-cost sorbent. Rice husk, a by-product of the rice milling industry, accounts for about 20 % of the whole rice. The argro-residue sorbent extracted from rice husk was employed in separation of zirconium from yttrium. The separation of Zr from the binary systems (Zr-Y) was achieved in batch and column modes. In a batch mode, the adsorption behavior was studied in deferent media, namely, hydrochloric acid, 0.1 M citrate buffer and 0.1 M acetate buffer. In addition, other factors affecting the sorption process of each metal e.g. ph-value of the medium and metal ion concentration were also studied. The breakthrough experiments were carried in the form of mini-column with different bed depths of sorbent at flow rates of 20 ml/min and 40 ml/min. These studies were performed to elucidate the valuable of use of locally, available, agro-residue for separation of Zr from Y target as a promising sorbent for purification of 88 Zr, 89 Zr from Y.

  4. Poly(styrene-co-N-methacryloyl-l-phenylalanine methyl ester)-functionalized magnetic nanoparticles as sorbents for the analysis of sodium benzoate in beverages.

    Science.gov (United States)

    Ji, Shilei; Li, Nan; Qi, Li; Wang, Minglin

    2017-01-01

    In this study, poly(styrene-co-N-methacryloyl-l-phenylalanine methyl ester)-functionalized magnetic nanoparticles were constructed and used as magnetic solid-phase extraction sorbents for analysis of food preservatives in beverages. To prepare the poly(amino acid)-based sorbents, N-methacryloyl-l-phenylalanine methyl ester, and styrene served as the functional monomers and modified onto the magnetic nanoparticles via free radical polymerization. Interestingly, compared with propylparaben and potassium sorbate, the proposed poly(amino acid)-based sorbents showed a good selectivity to sodium benzoate. The adsorption capacity of the sorbents to sodium benzoate was 6.08 ± 0.31 mg/g. Moreover, the fast adsorption equilibrium could be reached within 5 min. Further, the resultant poly(amino acid)-based sorbents were applied in the analysis of sodium benzoate in real beverage samples. The results proved that the proposed magnetic solid-phase extraction sorbents have a great potential for the analysis of preservatives in food samples. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Silica-Silver Nanocomposites as Regenerable Sorbents for Hg0 Removal from Flue Gases.

    Science.gov (United States)

    Cao, Tiantian; Li, Zhen; Xiong, Yong; Yang, Yue; Xu, Shengming; Bisson, Teresa; Gupta, Rajender; Xu, Zhenghe

    2017-10-17

    Silica-silver nanocomposites (Ag-SBA-15) are a novel class of multifunctional materials with potential applications as sorbents, catalysts, sensors, and disinfectants. In this work, an innovative yet simple and robust method of depositing silver nanoparticles on a mesoporous silica (SBA-15) was developed. The synthesized Ag-SBA-15 was found to achieve a complete capture of Hg 0 at temperatures up to 200 °C. Silver nanoparticles on the SBA-15 were shown to be the critical active sites for the capture of Hg 0 by the Ag-Hg 0 amalgamation mechanism. An Hg 0 capture capacity as high as 13.2 mg·g -1 was achieved by Ag(10)-SBA-15, which is much higher than that achievable by existing Ag-based sorbents and comparable with that achieved by commercial activated carbon. Even after exposure to more complex simulated flue gas flow for 1 h, the Ag(10)-SBA-15 could still achieve an Hg 0 removal efficiency as high as 91.6% with a Hg 0 capture capacity of 457.3 μg·g -1 . More importantly, the spent sorbent could be effectively regenerated and reused without noticeable performance degradation over five cycles. The excellent Hg 0 removal efficiency combined with a simple synthesis procedure, strong tolerance to complex flue gas environment, great thermal stability, and outstanding regeneration capability make the Ag-SBA-15 a promising sorbent for practical applications to Hg 0 capture from coal-fired flue gases.

  6. Sulfur poisoning in cattle

    Energy Technology Data Exchange (ETDEWEB)

    Julian, R J; Harrison, K B

    1975-01-01

    A case of sulfur poisoning is described in which 12 of 20 cattle died following the feeding of sulfur. Respiratory distress and abdominal pain were the prominent signs. Examination of one animal revealed vasculitis and necrosis of the rumen and abomasal wall. The possible toxic effects of sulfur are discussed.

  7. Moderate temperature gas purification system: Application to high calorific coal-derived fuel

    Energy Technology Data Exchange (ETDEWEB)

    Kobayashi, M.; Shirai, H.; Nunokawa, M. [Central Research Institute of Electric Power Industry, Kanagawa (Japan)

    2008-01-15

    Simultaneous removal of dust, alkaline and alkaline-earth metals, halides and sulfur compounds is required to enlarge application of coal-derived gas to the high-temperature fuel cells and the fuel synthesis through chemical processing. Because high calorific fuel gas, such as oxygen-blown coal gas, has high carbon monoxide content, high-temperature (above 450{sup o}C) gas purification system is always subjected to the carbon deposition. We suggest moderate temperature (around 300{sup o}C) operation of the gas purification system to avoid the harmful disproportionation reaction and efficient removal of the various contaminants. Because the reaction rate is predominant to the performance of contaminant removal in the moderate temperature gas purification system, we evaluated the chemical removal processes; performance of the removal processes for halides and sulfur compounds was experimentally evaluated. The halide removal process with sodium aluminate sorbent had potential performance at around 300{sup o}C. The sulfur removal process with zinc ferrite sorbent was also applicable to the temperature range, though the reaction kinetics of the sorbent is essential to be approved.

  8. A Comprehensive Model of the Dry Desulphurisation Process Une modélisation non empirique du procédé de désulfuration par voie sèche

    Directory of Open Access Journals (Sweden)

    Flament P.

    2006-11-01

    Full Text Available Due to the high investment cost of the wet scrubbing, the dry desulphurisation process remains an attractive way to remove sulphur dioxide when reduction level should not be higher than 90%. In this technique, the SO2 is removed from flue gases by direct injection of small calcium based sorbents such as calcium carbonate (CaCO3 or calcium hydroxide (Ca(OH² . The sorbent is first transformed into calcium oxide (CaO before reacting with SO2 to form a stable calcium sulphate (CaSO4. Although the global reactions are rather simple, a full description of the mechanism requires the knowledge of both, the initial physical properties of the sorbent and the evolution of these properties during the reaction. Furthermore, the way how particles are injected and dispersed into the SO2 containing gases is also a major issue of the dry desulphurisation process. Both aspects are considered in this paper since a specialised routine was build to describe the calcination-sulphation process and coupled with the KIVA code to perform 3D calculations under real industrial conditions. The desulphurisation model was first tested alone using the kinetic data of the International Flame Research Foundation and then, coupled with KIVA to simulate the desulphurisation process in a new type of boiler which is developed by BABCOCK Entreprise and the Institut Français du Pétrole (the AUDE boiler. In this last case, the objective was to determine the sorbent injection locations leading to the highest desulphurisation efficiencies. As the dispersion of particles is an important parameter of the desulphurisation process, an example of validation of the KIVA dispersion model is also presented in this paper. For the selected test case, i. e: particle dispersion in a plane mixing layer, a good agreement was found between the experimental results of Ando et al (1990 and the calculations performed with KIVA. Par suite du coût d'investissement très élevé du procédé de lavage

  9. Sulfur Earth

    Science.gov (United States)

    de Jong, B. H.

    2007-12-01

    Variations in surface tension affect the buoyancy of objects floating in a liquid. Thus an object floating in water will sink deeper in the presence of dishwater fluid. This is a very minor but measurable effect. It causes for instance ducks to drown in aqueous solutions with added surfactant. The surface tension of liquid iron is very strongly affected by the presence of sulfur which acts as a surfactant in this system varying between 1.9 and 0.4 N/m at 10 mass percent Sulfur (Lee & Morita (2002), This last value is inferred to be the maximum value for Sulfur inferred to be present in the liquid outer core. Venting of Sulfur from the liquid core manifests itself on the Earth surface by the 105 to 106 ton of sulfur vented into the atmosphere annually (Wedepohl, 1984). Inspection of surface Sulfur emission indicates that venting is non-homogeneously distributed over the Earth's surface. The implication of such large variation in surface tension in the liquid outer core are that at locally low Sulfur concentration, the liquid outer core does not wet the predominantly MgSiO3 matrix with which it is in contact. However at a local high in Sulfur, the liquid outer core wets this matrix which in the fluid state has a surface tension of 0.4 N/m (Bansal & Doremus, 1986), couples with it, and causes it to sink. This differential and diapiric movement is transmitted through the essentially brittle mantle (1024 Pa.s, Lambeck & Johnson, 1998; the maximum value for ice being about 1030 Pa.s at 0 K, in all likely hood representing an upper bound of viscosity for all materials) and manifests itself on the surface by the roughly 20 km differentiation, about 0.1 % of the total mantle thickness, between topographical heights and lows with concomitant lateral movement in the crust and upper mantle resulting in thin skin tectonics. The brittle nature of the medium though which this movement is transmitted suggests that the extremes in topography of the D" layer are similar in range to

  10. Using sorbent waste materials to enhance treatment of micro-point source effluents by constructed wetlands

    Science.gov (United States)

    Green, Verity; Surridge, Ben; Quinton, John; Matthews, Mike

    2014-05-01

    Sorbent materials are widely used in environmental settings as a means of enhancing pollution remediation. A key area of environmental concern is that of water pollution, including the need to treat micro-point sources of wastewater pollution, such as from caravan sites or visitor centres. Constructed wetlands (CWs) represent one means for effective treatment of wastewater from small wastewater producers, in part because they are believed to be economically viable and environmentally sustainable. Constructed wetlands have the potential to remove a range of pollutants found in wastewater, including nitrogen (N), phosphorus (P), biochemical oxygen demand (BOD) and carbon (C), whilst also reducing the total suspended solids (TSS) concentration in effluents. However, there remain particular challenges for P and N removal from wastewater in CWs, as well as the sometimes limited BOD removal within these treatment systems, particularly for micro-point sources of wastewater. It has been hypothesised that the amendment of CWs with sorbent materials can enhance their potential to treat wastewater, particularly through enhancing the removal of N and P. This paper focuses on data from batch and mesocosm studies that were conducted to identify and assess sorbent materials suitable for use within CWs. The aim in using sorbent material was to enhance the combined removal of phosphate (PO4-P) and ammonium (NH4-N). The key selection criteria for the sorbent materials were that they possess effective PO4-P, NH4-N or combined pollutant removal, come from low cost and sustainable sources, have potential for reuse, for example as a fertiliser or soil conditioner, and show limited potential for re-release of adsorbed nutrients. The sorbent materials selected for testing were alum sludge from water treatment works, ochre derived from minewater treatment, biochar derived from various feedstocks, plasterboard and zeolite. The performance of the individual sorbents was assessed through

  11. Ionic liquid-functionalized mesoporous sorbents and their use in the capture of polluting gases

    Science.gov (United States)

    Lee, Jong Suk; Koros, William J.; Bhuwania, Nitesh; Hillesheim, Patrick C.; Dai, Sheng

    2016-01-12

    A composite structure for capturing a gaseous electrophilic species, the composite structure comprising mesoporous refractory sorbent particles on which an ionic liquid is covalently attached, wherein said ionic liquid includes an accessible functional group that is capable of binding to said gaseous electrophilic species. In particular embodiments, the mesoporous sorbent particles are contained within refractory hollow fibers. Also described is a method for capturing a gaseous electrophilic species by use of the above-described composite structure, wherein the gaseous electrophilic species is contacted with the composite structure. In particular embodiments thereof, cooling water is passed through the refractory hollow fibers containing the IL-functionalized sorbent particles in order to facilitate capture of the gaseous electrophilic species, and then steam is passed through the refractory hollow fibers to facilitate release of the gaseous electrophilic species such that the composite structure can be re-used to capture additional gas.

  12. Sulphation of calcium-based sorbents in circulating fluidised beds under oxy-fuel combustion conditions

    Energy Technology Data Exchange (ETDEWEB)

    Francisco Garcia-Labiano; Luis F. de Diego; Alberto Abad; Pilar Gayan; Margarita de las Obras-Loscertales; Aranzazu Rufas; Juan Adanez [Instituto de Carboquimica (CSIC), Zaragoza (Spain). Dept. Energy and Environment

    2009-07-01

    Sulphur Retention (SR) by calcium-based sorbents is a process highly dependent on the temperature and CO{sub 2} concentration. In circulating fluidised beds combustors (CFBC's) operating under oxy-fuel conditions, the sulphation process takes place in atmospheres enriched in CO{sub 2} with bed concentrations that can vary from 40 to 95%. Under so high CO{sub 2} concentrations, very different from that in conventional coal combustion atmosphere with air, the calcination and sulphation behaviour of the sorbent must be defined to optimise the SR process in the combustor. The objective of this work was to determine the SO{sub 2} retention capacity of a Spanish limestone at typical oxy-fuel conditions in CFBC's. Long term duration tests of sulphation (up to 24 h), to simulate the residence time of sorbents in CFBC's, were carried out by thermogravimetric analysis (TGA). Clear behaviour differences were found under calcining and non-calcining conditions. Especially relevant was the result obtained at calcining conditions but close to the thermodynamic temperature given for sorbent calcination. This situation must be avoided in CFBC's because the CO{sub 2} produced inside the particle during calcination can destroy the particles if a non-porous sulphate product layer has been formed around the particle. The effect of the main variables on the sorbent sulphation such as SO{sub 2} concentration, temperature, and particle size were analysed in the long term TGA tests. These data were also used to determine the kinetic parameters for the sulphation under oxy-fuel combustion conditions, which were able to adequately predict the sulphation conversion values in a wide range of operating conditions. 20 refs., 5 figs., 2 tabs.

  13. Natural sorbents for decontamination of objects of urban territories

    International Nuclear Information System (INIS)

    Movchan, N.; Fedorenko, Yu.; Zlobenko, B.; Spigoun, A.

    1996-01-01

    This paper gives an information about the use of film coverings, based on natural sorbents, in decontamination of buildings, contaminated after the Chernobyl accident. This method has incontrovertible advantages in the beginning period after the accident and can be used for cleaning considerable areas of urban territories

  14. The Relative Influence of Turbulence and Turbulent Mixing on the Adsorption of Mercury within a Gas-Sorbent Suspension

    Science.gov (United States)

    Our previous investigations demonstrated that entrained flow or in-flight adsorption can be a more effective and flexible approach to trace gas adsorption than fixed sorbent beds. The present investigation establishes the turbulent mixing that accompanies sorbent injection is an ...

  15. Sulfur problems in Swedish agriculture

    Energy Technology Data Exchange (ETDEWEB)

    Johansson, O

    1959-01-01

    The present paper deals with some aspects of the sulfur situation in Swedish agriculture with special emphasis on the importance of and relationships among various sources of sulfur supply. An inventory of the sulfur content of Swedish soils and hay crops includes 649 soil samples and a corresponding number of hay samples from 59 locations. In a special investigation the samples were found to be representative of normal Swedish farm land. It is concluded that the amount of sulfur compounds in the air is the primary factor which determines the amount of sulfur added to the soil from the atmosphere. Compared with values obtained in other countries, the amount of sulfur added by the precipitation in Sweden is very low. The distribution in air and precipitation of sulfur from an industrial source was studied in a special investigation. An initial reason for the present study was the damage to vegetation caused by smoke from an industrial source. It was concluded that the average conditions in the vicinity of the industrial source with respect to smoke constituents in the air and precipitation were unfavorable only to the plants directly within a very narrow region. Relationships among the sulfur contents of air, of precipitation, of soils and of plants have been subject to special investigations. In the final general discussion and conclusions it is pointed out that the results from these investigations indicate evident differences in the sulfur status of Swedish soils. The present trend toward the use of more highly concentrated fertilizers poor in sulfur may be expected to cause a considerable change in the sulfur situation in Swedish agriculture. 167 references, 40 figures, 44 tables.

  16. Sorbent materials for rapid remediation of wash water during radiological event relief

    Energy Technology Data Exchange (ETDEWEB)

    Jolin, William C.; Kaminski, Michael

    2016-11-01

    Procedures for removing harmful radiation from interior and exterior surfaces of homes and businesses after a nuclear or radiological disaster may generate large volumes of radiologically contaminated waste water. Rather than releasing this waste water to potentially contaminate surrounding areas, it is preferable to treat it onsite. Retention barrels are a viable option because of their simplicity in preparation and availability of possible sorbent materials. This study investigated the use of aluminosilicate clay minerals as sorbent materials to retain 137Cs, 85Sr, and 152Eu. Vermiculite strongly retained 137Cs, though other radionuclides displayed diminished affinity for the surface. Montmorillonite exhibited increased affinity to sorb 85Sr and 152Eu in the presence of higher concentrations of 137Cs. To simulate flow within retention barrels, vermiculite was mixed with sand and used in small-scale column experiments. The GoldSim contaminate fate module was used to model breakthrough and assess the feasibility of using clay minerals as sorbent materials in retention barrels. The modeled radionuclide breakthrough profiles suggest that vermiculite-sand and montmorillonite-sand filled barrels could be used for treatment of contaminated water generated from field operations.

  17. Biogenic sulfur compounds and the global sulfur cycle

    International Nuclear Information System (INIS)

    Aneja, V.P.; Aneja, A.P.; Adams, D.F.

    1982-01-01

    Field measurements of biogenic sulfur compounds shows a great variation in concentrations and emission rates for H 2 S, DMS, CS 2 and COS. Measurements by the chamber method and estimates from micrometeorological sampling are employed to determine the earth-atmosphere flux of these gases. Much of the variation can be attributed to differences of climate and surface conditions, with marshes being a large source of biogenic sulfur (mean contribution 4 x 10 to the 6th ton/year maximum contribution 142 x 10 to the 6th ton/year). Considering that the estimated biogenic contribution needed to balance the global sulfur cycle ranges from 40- 230 x 10 to the 6th tons/year, the mean values are not sufficient to balance this cycle. Further experimental investigations are suggested in order to characterize the biogenic processes adequately

  18. Sorption characteristics of honeycomb type sorption element composed of organic sorbent; Yukikei shuchakuzai wo tofushita honeycomb jo shuchaku element nio shuchaku tokuse

    Energy Technology Data Exchange (ETDEWEB)

    Inaba, H.; Horibe, A. [Okayama University, Okayama (Japan); Kida, T.; Kaneda, M. [Japan Exlan Co. Ltd., Osaka (Japan)

    2000-12-25

    This paper has dealt with the sorption characteristics of honeycomb shape type sorbent element composed of new organic sorbent which was composed of the bridged complex of sodium polyacrylate. The transient experiments in which the moist air was passed into the honeycomb type sorbent element were conducted under various conditions of air velocity, temperature, relative-humidity and honeycomb length. As a result, the effective mass transfer coefficient of the organic sorbent sorbing the water-vapor was non-dimensionalized as a function of Reynolds number, modified Stefan number and non-dimensional honeycomb length. (author)

  19. A regenerable potassium and phosphate sorbent system to enhance dialysis efficacy and device portability: an in vitro study.

    Science.gov (United States)

    Wester, Maarten; Simonis, Frank; Gerritsen, Karin G; Boer, Walther H; Wodzig, Will K; Kooman, Jeroen P; Joles, Jaap A

    2013-09-01

    Continuous dialysis could provide benefit by constant removal of potassium and phosphate. This study investigates the suitability of specific potassium and phosphate sorbents for incorporation in an extracorporeal device by capacity and regenerability testing. Capacity testing was performed in uraemic plasma. Regenerability was tested for potassium sorbents, with adsorption based on cationic exchange for sodium, with 0.1 M and 1.0 M NaCl. To regenerate phosphate sorbents, with adsorption based on anionic exchange, 0.1 M and 1.0 M NaHCO3 and NaOH were used. Subsequently, sodium polystyrene divinylbenzene sulphonate (RES-A) and iron oxide hydroxide (FeOOH) beads were incorporated in a cartridge for testing in bovine blood using a recirculating blood circuit and a dialysis circuit separated by a high-flux dialyzer (dynamic setup). Preloading was tested to assess whether this could limit calcium and magnesium adsorption. In the batch-binding assays, zirconium phosphate most potently adsorbed potassium (0.44 ± 0.05 mmol/g) and RES-A was the best regenerable potassium sorbent (92.9 ± 5.7% with 0.1 M NaCl). Zirconium oxide hydroxide (ZIR-hydr) most potently adsorbed phosphate (0.23 ± 0.05 mmol/g) and the polymeric amine sevelamer carbonate was the best regenerable sorbent (85.7 ± 5.2% with 0.1 M NaHCO3). In the dynamic setup, a potassium adsorption of 10.72 ± 2.06 mmol in 3 h was achieved using 111 g of RES-A and a phosphate adsorption of 4.73 ± 0.53 mmol in 3 h using 55 g of FeOOH. Calcium and magnesium preloading was shown to reduce the net adsorption in 3 h from 3.57 ± 0.91 to -0.29 ± 1.85 and 1.02 ± 0.05 to -0.31 ± 0.18 mmol, respectively. RES-A and FeOOH are suitable, regenerizable sorbents for potassium and phosphate removal in dialysate regeneration. Use of zirconium carbonate and ZIR-hydr may further increase phosphate adsorption, but may compromise sorbent regenerability. Use of polymeric amines for phosphate adsorption may enhance sorbent

  20. 21 CFR 876.5600 - Sorbent regenerated dialysate delivery system for hemodialysis.

    Science.gov (United States)

    2010-04-01

    ... dialyzer. The device is used with the extracorporeal blood system and the dialyzer of the hemodialysis... dialysate conditions. The sorbent cartridge may include absorbent, ion exchange and catalytic materials. (b...

  1. Preparation of diatomite/Ca(OH){sub 2} sorbents and modelling their sulphation reaction Istanbul Technical University, Istanbul (Turkey). Chemical and Metallurgical Engineering Faculty

    Energy Technology Data Exchange (ETDEWEB)

    Nilgun Karatepe; Nilufer Erdoan; Aysegul Ersoy-Mericboyu; Sadriye Kucukbayrak

    2004-09-01

    Mixtures of Ca(OH){sub 2} and diatomite were hydrated at different conditions to produce reactive SO{sub 2} sorbents. Two different hydration techniques were used; namely, atmospheric and pressure hydration. The effect of the hydration temperature, time and diatomite/Ca(OH){sub 2} weight ratio on the physical properties of the activated sorbents were investigated. In atmospheric hydration, it was found that increasing the temperature and hydration time caused an increase in the total surface area of the sorbents. However, surface area values of the sorbents prepared from mixtures which have different diatomite/Ca(OH){sub 2} weight ratio were generally not changed significantly. In pressure hydration, the surface area of the activated sorbents was positively affected from the hydration temperature and pressure. Finally, Ca(OH){sub 2} and two diatomite/Ca(OH){sub 2} sorbents were sulphated at constant temperature (338 K) using a synthetic gaseous mixture consisting of 5% O{sub 2}, 10% CO{sub 2}, 5000 ppm SO{sub 2} and the balance of nitrogen with a 55% relative humidity. The sulphation reaction of these sorbents were investigated and modelled. The unreacted shrinking core model was chosen to describe this non-catalytic solid/gas (hydrated sorbent/SO{sub 2}) reaction mechanism. The experimental results were found to be correlated successfully by this model.

  2. Sorption-enhanced steam reforming of ethanol: thermodynamic comparison of CO{sub 2} sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Wu, Y.J.; Santos, J.C.; Cunha, A.F.; Rodrigues, A.E. [University of Porto, Faculty of Engineering, Department of Chemical Engineering, Associated Laboratory LSRE/LCM, Laboratory of Separation and Reaction Engineering, Porto (Portugal); Diaz Alvarado, F.; Gracia, F. [Universidad de Chile, Facultad de Ingenieria, Departamento de Ingenieria Quimica y Biotecnologia, Laboratorio de Catalisis, Santiago (Chile)

    2012-05-15

    A thermodynamic analysis is performed with a Gibbs free energy minimization method to compare the conventional steam reforming of ethanol (SRE) process and sorption-enhanced SRE (SE-SRE) with three different sorbents, namely, CaO, Li{sub 2}ZrO{sub 3}, and hydrotalcite-like compounds (HTlc). As a result, the use of a CO{sub 2} adsorbent can enhance the hydrogen yield and provide a lower CO content in the product gas at the same time. The best performance of SE-SRE is found to be at 500 C with an HTlc sorbent. Nearly 6 moles hydrogen per mole ethanol can be produced, when the CO content in the vent stream is less than 10 ppm, so that the hydrogen produced via SE-SRE with HTlc sorbents can be directly used for fuel cells. Higher pressures do not favor the overall SE-SRE process due to lower yielding of hydrogen, although CO{sub 2} adsorption is enhanced. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  3. Bench-scale Development of an Advanced Solid Sorbent-based CO2 Capture Process for Coal-fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Nelson, Thomas [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Kataria, Atish [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Soukri, Mustapha [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Farmer, Justin [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Mobley, Paul [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Tanthana, Jak [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Wang, Dongxiang [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Wang, Xiaoxing [Research Triangle Institute (RTI), Research Triangle Park, NC (United States); Song, Chunshan [Research Triangle Institute (RTI), Research Triangle Park, NC (United States)

    2015-12-31

    It is increasingly clear that CO2 capture and sequestration (CCS) must play a critical role in curbing worldwide CO2 emissions to the atmosphere. Development of these technologies to cost-effectively remove CO2 from coal-fired power plants is very important to mitigating the impact these power plants have within the world’s power generation portfolio. Currently, conventional CO2 capture technologies, such as aqueous-monoethanolamine based solvent systems, are prohibitively expensive and if implemented could result in a 75 to 100% increase in the cost of electricity for consumers worldwide. Solid sorbent CO2 capture processes – such as RTI’s Advanced Solid Sorbent CO2, Capture Process – are promising alternatives to conventional, liquid solvents. Supported amine sorbents – of the nature RTI has developed – are particularly attractive due to their high CO2 loadings, low heat capacities, reduced corrosivity/volatility and the potential to reduce the regeneration energy needed to carry out CO2 capture. Previous work in this area has failed to adequately address various technology challenges such as sorbent stability and regenerability, sorbent scale-up, improved physical strength and attrition-resistance, proper heat management and temperature control, proper solids handling and circulation control, as well as the proper coupling of process engineering advancements that are tailored for a promising sorbent technology. The remaining challenges for these sorbent processes have provided the framework for the project team’s research and development and target for advancing the technology beyond lab- and bench-scale testing. Under a cooperative agreement with the US Department of Energy, and part of NETL’s CO2 Capture Program, RTI has led an effort to address and mitigate the challenges associated with solid sorbent CO2 capture. The overall objective

  4. The effect of the synthesis method on the parameters of pore structure and selectivity of ferrocyanide sorbents based on natural minerals

    International Nuclear Information System (INIS)

    Voronina, A.V.; Gorbunova, T.V.; Semenishchev, V.S.

    2017-01-01

    Ferrocyanide sorbents were obtained via thin-layer and surface modification of natural clinoptilolite and marl. The effect of modification method on surface characteristics of these sorbents and their selectivity for cesium was studied. It was shown that the modification resulted in an increase of selectivity of modified ferrocyanide sorbents to cesium as compared with the natural clinoptilolite in presence of Na + , as well as in an increase of cesium distribution coefficients in presence of K + . The nickel-potassium ferrocyanide based on the clinoptilolite showed the highest selectivity for cesium at sodium concentrations of 10 -4 -2 mol L -1 : cesium distribution coefficient was lg K d = 4.5 ± 0.4 L kg -1 and cesium/sodium separation factor was α(Cs/Na) = 250. In the presence of NH 4 + , all modified sorbents showed approximately equal selectivity for 137 Cs. Probable applications of the sorbents were suggested. (author)

  5. Sulfur dimers adsorbed on Au(111) as building blocks for sulfur octomers formation: A density functional study

    International Nuclear Information System (INIS)

    Hernandez-Tamargo, Carlos E.; Montero-Alejo, Ana Lilian; Pujals, Daniel Codorniu; Mikosch, Hans; Hernández, Mayra P.

    2014-01-01

    Experimental scanning tunneling microscopy (STM) studies have shown for more than two decades rectangular formations when sulfur atoms are deposited on Au(111) surfaces. The precursors have ranged from simple molecules or ions, such as SO 2 gas or sulfide anions, to more complex organosulfur compounds. We investigated, within the framework of the Density Functional Theory, the structure of these rectangular patterns assuming them entirely composed of sulfur atoms as the experimental evidence suggests. The sulfur coverage at which the simulations were carried out (0.67 ML or higher) provoked that the sulfur-sulfur association had to be taken into account for achieving a good agreement between the sets of simulated and experimental STM images. A combination of four sulfur dimers per rectangular formation properly explained the trends obtained by the experimental STM analysis which were related with the rectangles' size and shape fluctuations together with sulfur-sulfur distances within these rectangles. Finally, a projected density of states analysis showed that the dimers were capable of altering the Au(5d) electronic states at the same level as atomic sulfur adsorbed at low coverage. Besides, sulfur dimers states were perfectly distinguished, whose presence near and above the Fermi level can explain both: sulfur-sulfur bond elongation and dimers stability when they stayed adsorbed on the surface at high coverage

  6. Sulfur dimers adsorbed on Au(111) as building blocks for sulfur octomers formation: A density functional study

    Energy Technology Data Exchange (ETDEWEB)

    Hernandez-Tamargo, Carlos E.; Montero-Alejo, Ana Lilian [Laboratory of Computational and Theoretical Chemistry (LQCT), Faculty of Chemistry, Havana University, Havana 10400 (Cuba); Pujals, Daniel Codorniu [Higher Institute of Technologies and Applied Sciences (InSTEC), Havana 10400 (Cuba); Mikosch, Hans [Institute of Chemical Technologies and Analytics, Vienna University of Technology, Getreidemarkt 9/E164-EC, 1060 Vienna (Austria); Hernández, Mayra P., E-mail: mayrap@imre.oc.uh.cu [Instituto de Ciencias y Tecnologías de Materiales (IMRE), Havana 10400 (Cuba)

    2014-07-28

    Experimental scanning tunneling microscopy (STM) studies have shown for more than two decades rectangular formations when sulfur atoms are deposited on Au(111) surfaces. The precursors have ranged from simple molecules or ions, such as SO{sub 2} gas or sulfide anions, to more complex organosulfur compounds. We investigated, within the framework of the Density Functional Theory, the structure of these rectangular patterns assuming them entirely composed of sulfur atoms as the experimental evidence suggests. The sulfur coverage at which the simulations were carried out (0.67 ML or higher) provoked that the sulfur-sulfur association had to be taken into account for achieving a good agreement between the sets of simulated and experimental STM images. A combination of four sulfur dimers per rectangular formation properly explained the trends obtained by the experimental STM analysis which were related with the rectangles' size and shape fluctuations together with sulfur-sulfur distances within these rectangles. Finally, a projected density of states analysis showed that the dimers were capable of altering the Au(5d) electronic states at the same level as atomic sulfur adsorbed at low coverage. Besides, sulfur dimers states were perfectly distinguished, whose presence near and above the Fermi level can explain both: sulfur-sulfur bond elongation and dimers stability when they stayed adsorbed on the surface at high coverage.

  7. Efficacy of the Molded Carbon Sorbent VNIITU-1 Used in Obstetric Practice

    Directory of Open Access Journals (Sweden)

    V. T. Dolgikh

    2015-01-01

    Full Text Available Objective: to develop a technology for obtaining the molded sorbent VNIITU1, to study its physicochemical and biomedical properties, and to evaluate its efficacy in preventing and treating pyoinflammatory complications in obstetrics.Materials and methods. The molded sorbent VNIITU-1 was designed from the carbon porous material based on nanodispersed carbon by mixing with a vehicle, extruding the mixture, drying the extrudate in an inert atmosphere, thermally treating and activating by steam, followed by washing with distilled water and drying (TU 9398043710698342013. The molded sorbent VNIITU-1 is apyrogenic and nontoxic (Toxicity Study Conclusion No. 1998.013.P dated 14.08.2013; Engineering Testing Assessment No. 12.404 ORTI/2013 dated 26.08.2013, it is destined for single administration, sterile, placed in a removable thread capron mesh container, and used to treat and prevent pyoseptic complications in puerperas at risk for infection, such as acute nonspecific postpartum endometritis. A total of 52 puerperas were examined and treated. They had been divided into 2 groups: a study group (n=37 and a comparison group (n=15. In the study group, the hemosorbent VNIITU1 as a porous carbon applicator was postpartum inserted into the uterine cavity, by concurrently performing traditional antibiotic therapy to prevent infectious complications. The comparison group received only traditional antibiotic therapy. The uterine cavity aspirate was examined for IL1β and IL6 levels, its microbial profile, and microbial growth patterns in culture media. The data were processed using a package of applied STATISTICA6.1 programs and standard mathematical tables in Microsoft Excel. Descriptive and variation statistical methods were applied. The data were presented as Me [low quartilehigh quartile (LQHQ]; two pre and posttreatment dependent variables were compared using the Wilcoxon and Mann-Whitney tests.Results. The molded carbon sorbent VNIITU1 was

  8. Genomic and Evolutionary Perspectives on Sulfur Metabolism in Green Sulfur Bacteria

    DEFF Research Database (Denmark)

    Frigaard, Niels-Ulrik; Bryant, Donald A.

    2008-01-01

    Green sulfur bacteria (GSB) are anaerobic photoautotrophs that oxidize sulfide, elemental sulfur, thiosulfate, ferrous iron, and hydrogen for growth. We present here an analysis of the distribution and evolution of enzymes involved in oxidation of sulfur compounds in GSB based on genome sequence......, in combination with phylogenetic analyses, suggests that the Dsr system in GSB could be a recent acquisition, which was obtained by lateral gene transfer in part from sulfideoxidizing bacteria and in part from sulfate-reducing bacteria. All thiosulfate-utilizing GSB strains have an identical sox gene cluster...

  9. Acidithiobacillus caldus sulfur oxidation model based on transcriptome analysis between the wild type and sulfur oxygenase reductase defective mutant.

    Directory of Open Access Journals (Sweden)

    Linxu Chen

    Full Text Available Acidithiobacillus caldus (A. caldus is widely used in bio-leaching. It gains energy and electrons from oxidation of elemental sulfur and reduced inorganic sulfur compounds (RISCs for carbon dioxide fixation and growth. Genomic analyses suggest that its sulfur oxidation system involves a truncated sulfur oxidation (Sox system (omitting SoxCD, non-Sox sulfur oxidation system similar to the sulfur oxidation in A. ferrooxidans, and sulfur oxygenase reductase (SOR. The complexity of the sulfur oxidation system of A. caldus generates a big obstacle on the research of its sulfur oxidation mechanism. However, the development of genetic manipulation method for A. caldus in recent years provides powerful tools for constructing genetic mutants to study the sulfur oxidation system.An A. caldus mutant lacking the sulfur oxygenase reductase gene (sor was created and its growth abilities were measured in media using elemental sulfur (S(0 and tetrathionate (K(2S(4O(6 as the substrates, respectively. Then, comparative transcriptome analysis (microarrays and real-time quantitative PCR of the wild type and the Δsor mutant in S(0 and K(2S(4O(6 media were employed to detect the differentially expressed genes involved in sulfur oxidation. SOR was concluded to oxidize the cytoplasmic elemental sulfur, but could not couple the sulfur oxidation with the electron transfer chain or substrate-level phosphorylation. Other elemental sulfur oxidation pathways including sulfur diooxygenase (SDO and heterodisulfide reductase (HDR, the truncated Sox pathway, and the S(4I pathway for hydrolysis of tetrathionate and oxidation of thiosulfate in A. caldus are proposed according to expression patterns of sulfur oxidation genes and growth abilities of the wild type and the mutant in different substrates media.An integrated sulfur oxidation model with various sulfur oxidation pathways of A. caldus is proposed and the features of this model are summarized.

  10. Supported modified hydrotalcites as sorbent for CO2 capture

    Energy Technology Data Exchange (ETDEWEB)

    Meis, N.

    2010-02-15

    The average concentration of CO2 in the atmosphere has been increasing since the start of the industrial revolution in the 18th century from 280 ppm to 385 ppm nowadays, and continues to increase because of the enormous human usage of fossil fuels (oil, gas, coal). This can strongly affect the climate, causing the Earth's surface to warm up, the so called 'amplified greenhouse effect'. To alleviate these environmental concerns regarding the current CO2 emissions into the atmosphere, Carbon Capture and Storage (CCS) is investigated as one of the possible routes. Due to the acidic character of CO2, basic oxides are expected to be suitable sorbents. Hydrotalcite, a natural clay, is specifically suitable for pre-combustion capture (250- 400{sup o}C), due to its acceptable sorption capacity and facile regeneration. The influence of lateral platelet size ({+-}40 nm - 2 {mu}m), the use of a support (carbon nanofibers, CNF) and addition of a promoter (alkali carbonate: K{sub 2}CO{sub 3}/Na{sub 2}CO{sub 3}) on the CO2 capture properties of HT was investigated. There was no significant difference in the CO2 sorption capacities at 523K for all unsupported HTs, regardless the platelet size of the HT precursor ({+-}0.1 mmol.g{sup -1}). The use of activated, promoted (alkali carbonate) hydrotalcites showed a much higher capacity ({+-}0.3 mmol.g{sup -1}) at 523K. In addition, the capacities of the activated supported HT at 523K were significantly increased compared to the activated unsupported HT (1.3-2.5 mmol.g{sup -1} HT). The alkali-loaded supported HTs showed capacities slightly higher than the capacity of supported unpromoted HT. The increase in capacity for the promoted and/or supported HTs points to a higher concentration of defects (low-coordination of oxygen sites) on the surface of the activated (alkali-)loaded HTs compared to the unloaded and unsupported HT. The higher concentration of adsorption for the promoted (supported) HTs, might be caused by the

  11. Carbon-Based Regenerable Sorbents for the Combined Carbon Dioxide and Ammonia Removal for the Primary Life Support System (PLSS)

    Science.gov (United States)

    Wojtowicz, Marek A.; Cosgrove, Joseph E.; Serio, Michael A.; Manthina, Venkata; Singh, Prabhakar; Chullen, Cinda

    2014-01-01

    Results are presented on the development of reversible sorbents for the combined carbon dioxide and trace-contaminant (TC) removal for use in Extravehicular Activities (EVAs). Since ammonia is the most important TC to be captured, data on TC sorption presented in this paper are limited to ammonia, with results relevant to other TCs to be reported at a later time. The currently available life support systems use separate units for carbon dioxide, trace contaminants, and moisture control, and the long-term objective is to replace the above three modules with a single one. Furthermore, the current TC-control technology involves the use of a packed bed of acid-impregnated granular charcoal, which is non-regenerable, and the carbon-based sorbent under development in this project can be regenerated by exposure to vacuum at room temperature. The objective of this study was to demonstrate the feasibility of using carbon sorbents for the reversible, concurrent sorption of carbon dioxide and ammonia. Several carbon sorbents were fabricated and tested, and multiple adsorption/vacuum-regeneration cycles were demonstrated at room temperature, and also a carbon surface conditioning technique that enhances the combined carbon dioxide and ammonia sorption without impairing sorbent regeneration.

  12. Application of Taguchi method for separation of uranium from acetate bearing wastewater using hydroxamic acid based sorbent

    International Nuclear Information System (INIS)

    Satpati, S.K.; Hareendran, K.; Roy, S.B.; Vaidya, A.; Bankar, V.; Dasgupta, K.; Pal, S.

    2016-01-01

    Separation and recovery of uranium from effluent of nuclear facility has drawn immense attention in separation science research. The acetic acid based uranium solution effluent generated in uranium metal powder production facility was targeted for the study. Solid state separation technique has been employed using hydroxamic acid based chelating sorbent because of several advantages. In the study, the sorbent performances have been evaluated for its important parameters like isotherm, efficiency and kinetics. The equilibrium adsorption capacity (q e ) and distribution coefficient (K d ) of U(VI) have been evaluated as 3.24 mg/g sorbent and 805 ml/g sorbent respectively. Uranium has been recovered using HCl solution. Uranium removal from the feed was found to be more than 95% and the recovery of uranium was more than 99% from the adsorbed phase. Elution process is faster than sorption process. Taguchi optimization method has been applied for designing experimental study and also to identify the optimum operational conditions for uranium separation process.The developed process is useful for separation and recovery of uranium from acetate bearing wastewater generated in uranium processing facilities

  13. Grafting the sol-gel based sorbents by diazonium salts: a novel approach toward unbreakable capillary microextraction.

    Science.gov (United States)

    Bagheri, Habib; Bayat, Parisa; Piri-Moghadam, Hamed

    2013-11-29

    The present work deals with a novel approach for grafting a sol-gel based sorbent, using diazonium salts for preparation of an unbreakable capillary microextraction (CME) device in on-line combination with high performance liquid chromatography (HPLC). The use of diazonium salts modifier allowed all types of metallic and non-metallic substrates to be used without any limitation. Substrates including copper, brass, stainless steel and polytetrafluoroethylene (PTFE) were chosen to be functionalized by chemical or electrochemical reduction of 4-amino phenyl acetic acid. Then, 3-(trimethoxysilyl)propylamine (3TMSPA) was selected as the precursor and the only reagent for preparation of the desired surface chemical bonded sorbent. The presence of chemical bond between substrate, diazonium salts and 3TMSPA is more probably responsible for thermal and solvent stability and long lifetime of the prepared sorbent. Characterization of the aryl group formation on the various substrates along with the prepared sorbents was thoroughly investigated by scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR) and thermogravimetry analysis (TGA). Typically, one of the prepared sorbents, deposited on the inner surface of the copper tube, was selected for assessing the developed method. The CME device was used for on-line extraction of atrazine, ametryn and terbutryn, as model compounds, from the aquatic media. After extraction, the HPLC mobile phase was used for on-line desorption and elution of the extracted analytes from the CME loop, containing the grafted sol-gel based sorbent, through the HPLC column. Figures of merit of the developed method were also obtained in which the linearity for the analytes was in the range of 30-1000μgL(-1). The value of LOD (S/N=3) for all analytes was 10μgL(-1) and the RSD% values (n=5) were all below 9.4% at the 500μgL(-1) level. Applicability of the developed method was examined by analyzing some real water samples in

  14. Biomimetic Ant-Nest Electrode Structures for High Sulfur Ratio Lithium-Sulfur Batteries.

    Science.gov (United States)

    Ai, Guo; Dai, Yiling; Mao, Wenfeng; Zhao, Hui; Fu, Yanbao; Song, Xiangyun; En, Yunfei; Battaglia, Vincent S; Srinivasan, Venkat; Liu, Gao

    2016-09-14

    The lithium-sulfur (Li-S) rechargeable battery has the benefit of high gravimetric energy density and low cost. Significant research currently focuses on increasing the sulfur loading and sulfur/inactive-materials ratio, to improve life and capacity. Inspired by nature's ant-nest structure, this research results in a novel Li-S electrode that is designed to meet both goals. With only three simple manufacturing-friendly steps, which include slurry ball-milling, doctor-blade-based laminate casting, and the use of the sacrificial method with water to dissolve away table salt, the ant-nest design has been successfully recreated in an Li-S electrode. The efficient capabilities of the ant-nest structure are adopted to facilitate fast ion transportation, sustain polysulfide dissolution, and assist efficient precipitation. High cycling stability in the Li-S batteries, for practical applications, has been achieved with up to 3 mg·cm(-2) sulfur loading. Li-S electrodes with up to a 85% sulfur ratio have also been achieved for the efficient design of this novel ant-nest structure.

  15. Aminosilane-Functionalized Hollow Fiber Sorbents for Post-Combustion CO 2 Capture

    KAUST Repository

    Li, Fuyue Stephanie

    2013-07-03

    Increasing carbon dioxide emissions are generally believed to contribute to global warming. Developing new materials for capturing CO2 emitted from coal-fired plants can potentially mitigate the effect of these CO 2 emissions. In this study, we developed and optimized porous hollow fiber sorbents with both improved sorption capacities and rapid sorption kinetics by functionalizing aminosilane (N-(2-aminoethyl)-3- aminoisobutyldimethylmethoxysilane) to cellulose acetate hollow fibers as a "proof of concept". A lumen-side barrier layer was also developed in the aminosilane-functionalized cellulose acetate fiber sorbent to allow for facile heat exchange without significant mass transfer with the bore-side heat transfer fluid. The functionalized cellulose acetate fiber sorbents were characterized by pressure decay sorption measurements, multicomponent column chromatography, FT-IR, elemental analysis, and scanning electron microscopy. The carbon dioxide sorption capacity at 1 atm is 0.73 mmol/g by using the pressure decay apparatus. Multicomponent column chromatography measurements showed that aminosilane functionalized cellulose acetate fiber sorbent has a CO2 sorption capacity of 0.23 mmol/g at CO2 partial pressure 0.1 atm and 35 C in simulated flue gas. While this capacity is low, our proof of concept positions the technology to move forward to higher capacity with work that is underway. The presence of silicon and nitrogen elements in the elemental analysis confirmed the success of grafting along with FT-IR spectra which showed the absorbance peak (∼810 cm-1) for Si-C stretching. A cross-linked Neoprene material was used to form the lumen-side barrier layer. Preliminary data showed the required reduction in gas permeance to eliminate mixing between shell side and bore side fluid flows. Specifically the permeance was reduced from 10 000 GPUs for the neat fibers to 6.6 ± 0.1 and 3.3 ± 0.3 GPUs for the coated fibers. The selected lumen layer formation materials

  16. Aminosilane-Functionalized Hollow Fiber Sorbents for Post-Combustion CO 2 Capture

    KAUST Repository

    Li, Fuyue Stephanie; Lively, Ryan P.; Lee, Jong Suk; Koros, William J.

    2013-01-01

    Increasing carbon dioxide emissions are generally believed to contribute to global warming. Developing new materials for capturing CO2 emitted from coal-fired plants can potentially mitigate the effect of these CO 2 emissions. In this study, we developed and optimized porous hollow fiber sorbents with both improved sorption capacities and rapid sorption kinetics by functionalizing aminosilane (N-(2-aminoethyl)-3- aminoisobutyldimethylmethoxysilane) to cellulose acetate hollow fibers as a "proof of concept". A lumen-side barrier layer was also developed in the aminosilane-functionalized cellulose acetate fiber sorbent to allow for facile heat exchange without significant mass transfer with the bore-side heat transfer fluid. The functionalized cellulose acetate fiber sorbents were characterized by pressure decay sorption measurements, multicomponent column chromatography, FT-IR, elemental analysis, and scanning electron microscopy. The carbon dioxide sorption capacity at 1 atm is 0.73 mmol/g by using the pressure decay apparatus. Multicomponent column chromatography measurements showed that aminosilane functionalized cellulose acetate fiber sorbent has a CO2 sorption capacity of 0.23 mmol/g at CO2 partial pressure 0.1 atm and 35 C in simulated flue gas. While this capacity is low, our proof of concept positions the technology to move forward to higher capacity with work that is underway. The presence of silicon and nitrogen elements in the elemental analysis confirmed the success of grafting along with FT-IR spectra which showed the absorbance peak (∼810 cm-1) for Si-C stretching. A cross-linked Neoprene material was used to form the lumen-side barrier layer. Preliminary data showed the required reduction in gas permeance to eliminate mixing between shell side and bore side fluid flows. Specifically the permeance was reduced from 10 000 GPUs for the neat fibers to 6.6 ± 0.1 and 3.3 ± 0.3 GPUs for the coated fibers. The selected lumen layer formation materials

  17. Desulfurization of AL-Ahdab Crude Oil using Oxidative Processes

    Directory of Open Access Journals (Sweden)

    Neran Khalel Ibrahim

    2015-07-01

    Full Text Available Two different oxidative desulfurization strategies based on oxidation/adsorption or oxidation/extraction were evaluated for the desulfurization of AL-Ahdab (AHD sour crude oil (3.9wt% sulfur content. In the oxidation process, a homogenous oxidizing agent comprising of hydrogen peroxide and formic acid was used. Activated carbons were used as sorbent/catalyst in the oxidation/adsorption process while acetonitrile was used as an extraction solvent in the oxidation/extraction process. For the oxidation/adsorption scheme, the experimental results indicated that the oxidation desulfurization efficiency was enhanced on using activated carbon as catalyst/sorbent. The effects of the operating conditions (contact time, temperature, mixing speed and sorbent dose on the desulfurization efficiency were examined. The desulfurization efficiency measured at the best operating conditions(optimum conditions: 60 , 500rpm, 60min contact time and sorbent dose of 0.7g AC/100 ml AHD crude, was 32.8% corresponding to a sulfur content of 2.6 wt%. Applying the same optimum operating conditions and at 3:1 solvent/oil ratio, the oxidation/extraction method gave comparable desulfurization efficiency of 31.5%.

  18. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir Gupta; Alejandro Lopez-Ortiz

    2001-01-01

    Four grades of sodium bicarbonate and two grades of trona were characterized in terms of particle size distribution, surface area, pore size distribution, and attrition. Surface area and pore size distribution determinations were conducted after calcination of the materials. The sorbent materials were subjected to thermogravimetric testing to determine comparative rates and extent of calcination (in inert gas) and sorption (in a simulated coal combustion flue gas mixture). Selected materials were exposed to five calcination/sorption cycles and showed no decrease in either sorption capacity or sorption rate. Process simulations were conducted involving different heat recovery schemes. The process is thermodynamically feasible. The sodium-based materials appear to have suitable physical properties for use as regenerable sorbents and, based on thermogravimetric testing, are likely to have sorption and calcination rates that are rapid enough to be of interest in full-scale carbon sequestration processes.

  19. Final Project Report for DOE/EERE High-Capacity and Low-Cost Hydrogen-Storage Sorbents for Automotive Applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, Hong-Cai [Texas A & M Univ., College Station, TX (United States); Liu, Di-Jia [Texas A & M Univ., College Station, TX (United States)

    2017-12-01

    This report provides a review of the objectives, progress, and milestones of the research conducted during this project on the topic of developing innovative metal-organic frameworks (MOFs) and porous organic polymers (POPs) for high-capacity and low-cost hydrogen-storage sorbents in automotive applications.1 The objectives of the proposed research were to develop new materials as next-generation hydrogen storage sorbents that meet or exceed DOE’s 2017 performance targets of gravimetric capacity of 0.055 kg H2/kgsystem and volumetric capacity of 0.040 kg H2/Lsystem at a cost of $400/kg H2 stored. Texas A&M University (TAMU) and Argonne National Laboratory (ANL) collaborated in developing low-cost and high-capacity hydrogen-storage sorbents with appropriate stability, sorption kinetics, and thermal conductivity. The research scope and methods developed to achieve the project’s goals include the following: Advanced ligand design and synthesis to construct MOF sorbents with optimal hydrogen storage capacities, low cost and high stability; Substantially improve the hydrogen uptake capacity and chemical stability of MOF-based sorbents by incorporating high valent metal ions during synthesis or through the post-synthetic metal metathesis oxidation approach; Enhance sorbent storage capacity through material engineering and characterization; Generate a better understanding of the H2-sorbent interaction through advanced characterization and simulation. Over the course of the project 5 different MOFs were developed and studied: PCN-250, PCN-12, PCN-12’, PCN-608 and PCN-609.2-3 Two different samples were submitted to the National Renewable Energy Laboratory (NREL) in order to validate their hydrogen adsorption capacity, PCN-250 and PCN-12. Neither of these samples reached the project’s Go/No-Go requirements but the data obtained did further prove the hypothesis that the presence of open metal

  20. Capacity Fade Analysis of Sulfur Cathodes in Lithium–Sulfur Batteries

    Science.gov (United States)

    Yan, Jianhua; Liu, Xingbo

    2016-01-01

    Rechargeable lithium–sulfur (Li–S) batteries are receiving ever‐increasing attention due to their high theoretical energy density and inexpensive raw sulfur materials. However, their rapid capacity fade has been one of the key barriers for their further improvement. It is well accepted that the major degradation mechanisms of S‐cathodes include low electrical conductivity of S and sulfides, precipitation of nonconductive Li2S2 and Li2S, and poly‐shuttle effects. To determine these degradation factors, a comprehensive study of sulfur cathodes with different amounts of electrolytes is presented here. A survey of the fundamentals of Li–S chemistry with respect to capacity fade is first conducted; then, the parameters obtained through electrochemical performance and characterization are used to determine the key causes of capacity fade in Li–S batteries. It is confirmed that the formation and accumulation of nonconductive Li2S2/Li2S films on sulfur cathode surfaces are the major parameters contributing to the rapid capacity fade of Li–S batteries. PMID:27981001

  1. Rubidium extraction using an organic polymer encapsulated potassium copper hexacyanoferrate sorbent

    KAUST Repository

    Naidu, Gayathri; Loganathan, Paripurnanda; Jeong, Sanghyun; Johir, Md.Abu Hasan; To, Vu Hien Phuong; Kandasamy, Jaya; Vigneswaran, Saravanamuthu

    2016-01-01

    Sea water reverse osmosis (SWRO) brine contains significant quantity of Rb. As an economically valuable metal, extracting Rb using a suitable and selective extraction method would be beneficial. An inorganic sorbent, copper based potassium

  2. Sulfur contents and sulfur-isotope compositions of thiotrophic symbioses in bivalve molluscs and vestimentiferan worms

    Science.gov (United States)

    Vetter, R.D.; Fry, B.

    1998-01-01

    Total sulfur (S(TOT)), elemental sulfur (S??) and sulfur-isotope compositions (??34S) of marine animals were analyzed to determine whether these chemical characteristics could help distinguish animals with a sulfur-based, thiotrophic nutrition from animals whose nutrition is based on methanotrophy or on more normal consumption of phytoplankton-derived organic matter. The presence of S??was almost entirely confined to the symbiont-containing tissues of thiotrophs, but was sometimes undetectable in thiotrophic species where sulfide availability was probably low. When S??contents were subtracted, the remaining tissue-sulfur concentrations were similar for all nutritional groups. ??34S values were typically lower for thiotrophs than for other groups, although there was overlap in methanotroph and thiotroph values at some sites. Field evidence supported the existence of small to moderate (1 to 10???)34S fractionations in the uptake of sulfides and metabolism of thiosulfate. In general, a total sulfur content of >3% dry weight, the presence of elemental sulfur, and ??34S values less than + 5??? can be used to infer a thiotrophic mode of nutrition.

  3. Layered sulfur/PEDOT:PSS nano composite electrodes for lithium sulfur cell applications

    Science.gov (United States)

    Anilkumar, K. M.; Jinisha, B.; Manoj, M.; Pradeep, V. S.; Jayalekshmi, S.

    2018-06-01

    Lithium-Sulfur (Li-S) cells are emerging as the next generation energy storage devices owing to their impressive electrochemical properties with high theoretical specific capacity of 1675 mAh/g. Lack of electronic conductivity of sulfur, its volume expansion during high lithium intake and the shuttling effect due to the formation of soluble polysulfides are the main limitations, delaying the commercialization of this technology. To address these challenges, in the present work, the conducting polymer PEDOT:PSS is used as the covering matrix over the sulfur particles to improve their Li storage properties. The sulfur/PEDOT:PSS nanocomposite is synthesised using the hydrothermal process and its formation with the polymer coating over sulfur nanoparticles is established from the XRD, Raman spectroscopy, FE-SEM and TEM studies. The electrochemical studies show that the cells assembled using the sulfur/PEDOT:PSS nanocomposite as the cathode, with the components taken in the weight ratio of 9:1, offer a reversible capacity of 1191 mAh g-1 at 0.1C rate. These cells display stable electrochemical capacities over 200 cycles at gradually increasing current rates. The polymer layer facilitates electronic conduction and suppresses the polysulfide formation and the volume expansion of sulfur. A reversible capacity of 664 mAh g-1 is observed after 200 cycles at 1C rate with the capacity retention of 75 % of the initial stable capacity. The highlight of the present work is the possibility to achieve high discharge capacities at high C rates and the retention of a good percentage of the initial capacity over 200 cycles, for these Li-S cells.

  4. Demand outlook for sulfur and high-sulfur petroleum coke

    Energy Technology Data Exchange (ETDEWEB)

    Koshkarov, V.Ya.; Danil' yan, P.G.; Feotov, V.E.; Gimaev, R.N.; Koshkarova, M.E.; Sadykova, S.R.; Vodovichenko, N.S.

    1980-01-01

    The feasibility of using sulfur and high-sulfur petroleum coke fines in pyrometallurgical processes and also in the chemical and coal-tar chemical industry is examined. Results of industrial tests on briquetting fines of petroleum coke with a petroleum binder are presented. The feasibility of using the obtained briquets in shaft furnace smelting of oxidized nickel ores, production of anode stock, and also in the chemical industry are demonstrated.

  5. SULFUR POLYMER ENCAPSULATION

    International Nuclear Information System (INIS)

    KALB, P.

    2001-01-01

    Sulfur polymer cement (SPC) is a thermoplastic polymer consisting of 95 wt% elemental sulfur and 5 wt% organic modifiers to enhance long-term durability. SPC was originally developed by the U.S. Bureau of Mines as an alternative to hydraulic cement for construction applications. Previous attempts to use elemental sulfur as a construction material in the chemical industry failed due to premature degradation. These failures were caused by the internal stresses that result from changes in crystalline structure upon cooling of the material. By reacting elemental sulfur with organic polymers, the Bureau of Mines developed a product that successfully suppresses the solid phase transition and significantly improves the stability of the product. SPC, originally named modified sulfur cement, is produced from readily available, inexpensive waste sulfur derived from desulfurization of both flue gases and petroleum. The commercial production of SPC is licensed in the United States by Martin Resources (Odessa, Texas) and is marketed under the trade name Chement 2000. It is sold in granular form and is relatively inexpensive ((approx)$0.10 to 0.12/lb). Application of SPC for the treatment of radioactive, hazardous, and mixed wastes was initially developed and patented by Brookhaven National Laboratory (BNL) in the mid-1980s (Kalb and Colombo, 1985; Colombo et al., 1997). The process was subsequently investigated by the Commission of the European Communities (Van Dalen and Rijpkema, 1989), Idaho National Engineering Laboratory (Darnell, 1991), and Oak Ridge National Laboratory (Mattus and Mattus, 1994). SPC has been used primarily in microencapsulation applications but can also be used for macroencapsulation of waste. SPC microencapsulation has been demonstrated to be an effective treatment for a wide variety of wastes, including incinerator hearth and fly ash; aqueous concentrates such as sulfates, borates, and chlorides; blowdown solutions; soils; and sludges. It is not

  6. CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

    Energy Technology Data Exchange (ETDEWEB)

    David A. Green; Brian S. Turk; Raghubir P. Gupta; Alejandro Lopez-Ortiz; Douglas P. Harrison; Ya Liang

    2001-07-01

    Sodium based sorbents including sodium carbonate may be used to capture carbon dioxide from flue gas. A relatively concentrated carbon dioxide stream may be recoverable for sequestration when the sorbent is regenerated. Electrobalance tests indicated that sodium carbonate monohydrate was formed in a mixture of helium and water vapor at temperatures below 65 C. Additional compounds may also form, but this could not be confirmed. In the presence of carbon dioxide and water vapor, both the initial reaction rate of sodium carbonate with carbon dioxide and water and the sorbent capacity decreased with increasing temperature, consistent with the results from the previous quarter. Increasing the carbon dioxide concentration at constant temperature and water vapor concentration produced a measurable increase in rate, as did increasing the water vapor concentration at constant carbon dioxide concentration and temperature. Runs conducted with a flatter TGA pan resulted in a higher initial reaction rate, presumably due to improved gas-solid contact, but after a short time, there was no significant difference in the rates measured with the different pans. Analyses of kinetic data suggest that the surface of the sodium carbonate particles may be much hotter than the bulk gas due to the highly exothermic reaction with carbon dioxide and water, and that the rate of heat removal from the particle may control the reaction rate. A material and energy balance was developed for a cyclic carbonation/calcination process which captures about 26 percent of the carbon dioxide present in flue gas available at 250 C.

  7. Confine sulfur in mesoporous metal–organic framework @ reduced graphene oxide for lithium sulfur battery

    International Nuclear Information System (INIS)

    Bao, Weizhai; Zhang, Zhian; Qu, Yaohui; Zhou, Chengkun; Wang, Xiwen; Li, Jie

    2014-01-01

    Highlights: • Metal organic framework @ reduced graphene oxide was applied for sulfur cathode. • MIL-101(Cr)@rGO/S composites are synthesized by a facile two-step liquid method. • Cycling stability of MIL-101(Cr)@rGO/S sulfur cathode was improved. -- Abstract: Mesoporous metal organic framework @ reduced graphene oxide (MIL-101(Cr)@rGO) materials have been used as a host material to prepare the multi-composite sulfur cathode through a facile and effective two-step liquid phase method successfully, which is different from the simple MIL-101(Cr)/S mixed preparation method. The successful reduced graphene oxide coating in the MIL-101(Cr)@rGO improve the electronic conductivity of meso-MOFs effectively. The discharge capacity and capacity retention rate of MIL-101(Cr)@rGO/S composite sulfur cathode are as high as 650 mAh g −1 and 66.6% at the 50th cycle at the current density of 335 mA g −1 . While the discharge capacity and capacity retention rate of MIL-101(Cr)/S mixed sulfur cathode is 458 mAh g −1 and 37.3%. Test results indicate that the MIL-101(Cr)@rGO is a promising host material for the sulfur cathode in the lithium–sulfur battery applications

  8. Removal of metals from industrial wastewater and urban runoff by mineral and bio-based sorbents.

    Science.gov (United States)

    Gogoi, Harshita; Leiviskä, Tiina; Heiderscheidt, Elisangela; Postila, Heini; Tanskanen, Juha

    2018-03-01

    The study was performed to evaluate chemically modified biosorbents, hydrochloric acid treated peat (HCl-P) and citric acid treated sawdust (Citric acid-SD) for their metal removal capacity from dilute industrial wastewater and urban runoff and compare their efficiency with that of commercially available mineral sorbents (AQM PalPower M10 and AQM PalPower T5M5 magnetite). Batch and column experiments were conducted using real water samples to assess the sorbents' metal sorption capacity. AQM PalPower M10 (consisting mainly of magnesium, iron and silicon oxides) exhibited excellent Zn removal from both industrial wastewater and spiked runoff water samples even at low dosages (0.1 g/L and 0.05 g/L, respectively). The high degree of Zn removal was associated with the release of hydroxyl ions from the sorbent and subsequent precipitation of zinc hydroxide. The biosorbents removed Ni and Cr better than AQM PalPower M10 from industrial wastewater and performed well in removing Cr and Cu from spiked runoff water, although at higher dosages (0.3-0.75 g/L). The main mechanism of sorption by biosorbents was ion exchange. The sorbents required a short contact time to reach equilibrium (15-30 min) in both tested water samples. AQM PalPower T5M5 magnetite was the worst performing sorbent, leaching Zn into both industrial and runoff water and Ni into runoff water. Column tests revealed that both HCl-P and AQM PalPower M10 were able to remove metals, although some leaching was witnessed, especially As from AQM PalPower M10. The low hydraulic conductivity observed for HCl-P may restrict the possibilities of using such small particle size peat material in a filter-type passive system. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Stability of sulfur slopes on Io

    Science.gov (United States)

    Clow, G. D.; Carr, M. H.

    1980-01-01

    The mechanical properties of elemental sulfur are such that the upper crust of Io cannot be primarily sulfur. For heat flows in the range 100-1000 ergs/sq cm sec sulfur becomes ductile within several hundred meters of the surface and would prevent the formation of calderas with depths greater than this. However, the one caldera for which precise depth data are available is 2 km deep, and this value may be typical. A study of the mechanical equilibrium of simple slopes shows that the depth to the zone of rapid ductile flow strongly controls the maximum heights for sulfur slopes. Sulfur scarps with heights greater than 1 km will fail for all heat flows greater than 180 ergs/sq cm sec and slope angles greater than 22.5 deg. The observed relief on Io is inconsistent with that anticipated for a predominantly sulfur crust. However, a silicate crust with several percent sulfur included satisfies both the mechanical constraints and the observed presence of sulfur on Io.

  10. 40 CFR 52.1881 - Control strategy: Sulfur oxides (sulfur dioxide).

    Science.gov (United States)

    2010-07-01

    ....0 pounds of sulfur dioxide per million BTU actual heat input for the coal-fired boiler and 0.4... BTU actual heat input for coal-fired boiler C exiting through stack 5. (3) 2.24 pounds of sulfur dioxide per million BTU acutal heat input for coal-fired boiler D exiting through stack 6. (E) In lieu of...

  11. Solvent extraction of elemental sulfur from coal and a determination of its source using stable sulfur isotopes

    Science.gov (United States)

    Hackley, Keith C.; Buchanan, D.H.; Coombs, K.; Chaven, C.; Kruse, C.W.

    1990-01-01

    Hot tetrachloroethene (perchloroethylene, PCE) extracts significant amounts of elemental sulfur (So) from weathered coals but not from pristine coals. The objective of this study was to determine whether So extracted by PCE is an oxidation product of pyrite or whether it originates in some way from unstable, organically-bound sulfur. The isotopic composition of the PCE-extracted So was compared to the isotopic compositions of the pyritic and the organic sulfur in a coal. The So was shown to have an isotopic signature similar to the pyritic sulfur. Additionally, the isotopic differences observed between the pyritic, So and sulfatic sulfur were consistent with bacterial mediated oxidation of sulfide sulfur (pyrite) as the source of both the sulfatic and elemental sulfur. ?? 1990.

  12. SYNTHESIS OF SULFUR-BASED WATER TREATMENT AGENT FROM SULFUR DIOXIDE WASTE STREAMS

    Energy Technology Data Exchange (ETDEWEB)

    Robert C. Brown; Maohong Fan; Adrienne Cooper

    2002-10-01

    Absorption of sulfur dioxide from a simulated flue gas was investigated for the production of polymeric ferric sulfate (PFS), a highly effective coagulant useful in treatment of drinking water and wastewater. The reaction for PFS synthesis took place near atmospheric pressure and at temperatures of 30-80 C. SO{sub 2} removal efficiencies greater than 90% were achieved, with ferrous iron concentrations in the product less than 0.1%. A factorial analysis of the effect of temperature, oxidant dosage, SO{sub 2} concentration, and gas flow rate on SO{sub 2} removal efficiency was carried out, and statistical analyses are conducted. The solid PFS was also characterized with different methods. Characterization results have shown that PFS possesses both crystalline and non-crystalline structure. The kinetics of reactions among FeSO{sub 4} {center_dot} 7H{sub 2}O, NaHSO{sub 3} and NaClO{sub 3} was investigated. The PFS product was used in pilot-scale tests at a municipal water treatment facility and gave good results in removal of turbidity and superior results in removal of disinfection byproduct precursors (TOC, DOC, UV-254) when compared with equal doses of ferric chloride.

  13. Adsorption of gaseous RuO4 by various sorbents. II

    International Nuclear Information System (INIS)

    Vujisic, L.; Nikolic, R.

    1983-01-01

    Sorption of gaseous RuO 4 on impregnated Alcoa Alumina H-151, impregnated charcoal, silica gel and HEPA filter was investigated. The results obtained on various sorbents are compared and discussed in connection with possibilities to use the chosen material in air cleaning systems

  14. The spectroscopic study of building composites containing natural sorbents.

    Science.gov (United States)

    Król, M; Mozgawa, W

    2011-08-15

    This work presents the results of FT-IR spectroscopic studies of heavy metal cations (Ag(+), Pb(2+), Zn(2+), Cd(2+) and Cr(3+)) immobilization from aqueous solutions on natural sorbents. The sorption has been conducted on sodium forms of zeolite (clinoptilolite) and clay minerals (mixtures containing mainly montmorillonite and kaolinite) which have been separated from natural Polish deposit. In the next part of the work both sorbents were used to obtain new building composites. It was proven those heavy metal cations' sorption causes changes in IR spectra of the zeolite and clay minerals. These alterations are dependent on the way the cations were sorbed. In the case of zeolite, variations of the bands corresponding to the characteristic ring vibrations have been observed. These rings occur in pseudomolecular complexes 4-4-1 (built of alumino- and silicooxygen tetrahedra) which constitute the secondary building units (SBU) and form spatial framework of the zeolite. The most significant changes have been determined in the region of pseudolattice vibrations (650-700 cm(-1)). In the instance of clay minerals, changes in the spectra occur at two ranges: 1200-800 cm(-1)--the range of the bands assigned to asymmetric Si-O(Si,Al) and bending Al-OH vibrations and 3800-3000 cm(-1)--the range of the bands originating from OH(-) groups stretching vibrations. Next results indicate possibilities of applying the used natural sorbents for the obtainment of new building materials having favourable composition and valuable properties. The zeolite was used for obtaining autoclaved materials with an addition of CaO, and the clay minerals for ceramic sintered materials with an addition of quartz and clinoptilolite were produced. FT-IR studies were also conducted on the obtained materials. Copyright © 2010 Elsevier B.V. All rights reserved.

  15. TG-FTIR measurement of CO2-H2O co-adsorption for CO2 air capture sorbent screening

    NARCIS (Netherlands)

    Smal, I.M.; Yu, Qian; Veneman, Rens; Fränzel-Luiten, B.; Brilman, Derk Willem Frederik

    2014-01-01

    Capturing atmospheric CO2 using solid sorbents is gaining interest. As ambient air normally contains much more (up to 100 times) water than CO2, a selective sorbent is desirable as co-adsorption will most likely occur. In this study, a convenient method based on an TG-FTIR analysis system is

  16. New Composite Sorbents for Caesium and Strontium Ions Sorption

    Directory of Open Access Journals (Sweden)

    Mykola Kartel

    2017-06-01

    Full Text Available Composite lignocellulose-inorganic sorbents derived from plant residues of agriculture and food industry, modified with ferrocyanides of d-metals and hydrated antimony pentoxide were prepared. Caesium and strontium ions removal from water was tested by radiotracer method. Sorption of heavy metal ions, methylene blue, gelatin, vitamin B12 was also studied.

  17. Solvent extraction of elemental sulfur from coal and a determination of its source using stable sulfur isotopes

    Energy Technology Data Exchange (ETDEWEB)

    Hackley, K.C.; Buchanan, D.H.; Coombs, K.; Chaven, C.; Kruse, C.W. (Eastern Illinois University, Charleston, IL (USA). Chemistry Dept.)

    1990-01-01

    Hot tetrachloroethene (perchloroethylen PCE) extracts significant amounts of elemental sulfur (S{sup o}) from weathered coals but not from pristine coals. The objective of this study was to determine whether S{sup o} extracted by PCE is an oxidation product of pyrite or whether it originates in some way from unstable, organically-bound sulfur. The isotopic composition of the PCE-extracted S{sup o} was compared to the isotopic compositions of the pyritic and the organic sulfur in a coal. The S{sup o} was shown to have an isotopic signature similar to the pyritic sulfur. Additionally, the isotopic differences observed between the pyritic, S{sup o} and sulfatic sulfur were consistent with bacterial mediated oxidation of sulfide sulfur (pyrite) as the source of both the sulfatic and elemental sulfur. 21 refs., 2 tabs.

  18. Sulfur-centered reactive intermediates derived from the oxidation of sulfur compounds of biological interest

    Energy Technology Data Exchange (ETDEWEB)

    Abedinzadeh, Z. [Lab. de Chimie Physique, UMR, Univ. Rene Descartes, Paris (France)

    2001-02-01

    Sulphur compounds play a central role in the structure and activity of many vital systems. In the living cell, sulfur constitutes an essential part of the defense against oxidative damage and is transformed into a variety of sulfur free radical species. Many studies of the chemistry of sulfur-centered radicals using pulse radiolysis and photolysis techniques to detect and measure the kinetics of these radicals have been published and reviewed. This paper discusses the present state of research on the formation and reactivity of certain sulfur-centered radicals [RS{sup .}, RSS{sup .}, RS{sup .+}, (RSSR){sup .+}] and their implications for biological systems. (author)

  19. Sulfur-centered reactive intermediates derived from the oxidation of sulfur compounds of biological interest

    International Nuclear Information System (INIS)

    Abedinzadeh, Z.

    2001-01-01

    Sulphur compounds play a central role in the structure and activity of many vital systems. In the living cell, sulfur constitutes an essential part of the defense against oxidative damage and is transformed into a variety of sulfur free radical species. Many studies of the chemistry of sulfur-centered radicals using pulse radiolysis and photolysis techniques to detect and measure the kinetics of these radicals have been published and reviewed. This paper discusses the present state of research on the formation and reactivity of certain sulfur-centered radicals [RS . , RSS . , RS .+ , (RSSR) .+ ] and their implications for biological systems. (author)

  20. Danburite decomposition by sulfuric acid

    International Nuclear Information System (INIS)

    Mirsaidov, U.; Mamatov, E.D.; Ashurov, N.A.

    2011-01-01

    Present article is devoted to decomposition of danburite of Ak-Arkhar Deposit of Tajikistan by sulfuric acid. The process of decomposition of danburite concentrate by sulfuric acid was studied. The chemical nature of decomposition process of boron containing ore was determined. The influence of temperature on the rate of extraction of boron and iron oxides was defined. The dependence of decomposition of boron and iron oxides on process duration, dosage of H 2 SO 4 , acid concentration and size of danburite particles was determined. The kinetics of danburite decomposition by sulfuric acid was studied as well. The apparent activation energy of the process of danburite decomposition by sulfuric acid was calculated. The flowsheet of danburite processing by sulfuric acid was elaborated.

  1. Experimentation of netlike hydro gel nitrogen containing polymer sorbents for biological liquids purification

    International Nuclear Information System (INIS)

    Karieva, Z.M.; Karimova, N. Kh.

    2003-01-01

    The high efficiency of hydrogels synthesized earlier in comparison with Pharmacopoeia sorbents are interesting to study comprehensively for the number of the toxins of biological liquids. Taking into considerations the high electoral sorption ability of ethynilpiperidol polymers to the hydro phobic interaction it may be suggested that they have a high detoxication ability. The detoxication characteristics of studied polymers have advantages over the known sorbents. Experiences with animals showed that in identical conditions of experiment in application of netlike polymers the survival grew 90%. Synthesis and investigations of netlike hydrogels polymer materials on nitrogen containing monomers of ethynil piperidol were given in the work. (author)

  2. Sulfur polymer cement concrete

    International Nuclear Information System (INIS)

    Weber, H.H.; McBee, W.C.

    1990-01-01

    Sulfur-based composite materials formulated using sulfur polymer cement (SPC) and mineral aggregates are described and compared with conventional portland cement based materials. Materials characteristics presented include mechanical strength, chemical resistance, impact resistance, moisture permeation, and linear shrinkage during placement and curing. Examples of preparation and placement of sulfur polymer cement concrete (SC) are described using commercial scale equipment. SC applications presented are focused into hostile chemical environments where severe portland cement concrete (PCC) failure has occurred

  3. Polymeric supported sorbents for decreasing hazardous metal ions content in wet process phosphoric acid

    International Nuclear Information System (INIS)

    El-Zahhar, A.A.; El-Naggar, H.A.; Ahmed, M.

    2005-01-01

    Procedure for preparation of polymeric supported silica, and their usage for decreasing hazardous metal ion content in wet process phosphoric acid was developed. The procedure is based firstly on extraction silica from rice straw by alkaline treatment , secondly supporting the produced silica on binding polyacrylonitrile (PAN). The produced polymer based sorbent was used for decreasing hazardous metal ions (especially iron) present as inorganic impurities in crud Egyptian phosphoric acid (green acid). Different factors affecting the sorption equilibrium ( contact time, temperature , sorbent mass and batch factor ) were studied. Studying the sorption isotherm revealed that the adsorption data could favorably fit the Langmuir adsorption isotherm. In the dynamic study , the sorption capacity at (Cξ/Cο = 50%) was found to be 28.5 mg/g and the loaded column could be regenerated using 50ml of 0.15 M HNO 3 . The regenerated column could undergo sorption regeneration cycles up to four cycles without significant decrease in the sorption capacity , weight loss or change in the physical properties of the sorbent

  4. Assessment of raw luffa as a natural hollow oleophilic fibrous sorbent for oil spill cleanup

    Directory of Open Access Journals (Sweden)

    Ola Abdelwahab

    2014-03-01

    Full Text Available Oil spills have a global concern due to its environmental and economical impact. Various commercial systems have been developed to control these spills, including the use of fibers as sorbents. However, plant biomass is renewable resource that can be converted into useful materials and energy. Luffa, an agricultural waste, was used as a sorbent material. The present study examines the adsorption capacity of raw luffa fibers for different types of oil and water pickup. The investigation revealed that the efficiency of fibers to remove crude oil from sea water was related to the surface properties of the fibers, concentration of the oil, amount of the fibers, as well as the temperature of the crude oil. The results show high sorption efficiency of luffa fibers for different kinds of oil. This sorbent also exhibited a good reusability since the decrease in sorption efficiency did not exceed 50% of the initial value after three sorption cycles.

  5. Method of preparation of a CO.sub.2 removal sorbent with high chemical stability during multiple cycles

    Science.gov (United States)

    Siriwardane, Ranjani V.; Rosencwaig, Shira

    2015-07-14

    Method for the production of a clay-alkali-amine CO.sub.2 sorbent prepared by integrating a clay substrate, basic alkali salt, and amine liquid. The basic alkali salt is present relative to the clay substrate in a weight ratio of from about 1 part to about 50 parts per 100 parts of the clay substrate. The amine liquid is present relative to a clay-alkali combination in a weight ratio of from about 1 part to about 10 parts per 10 parts of the clay-alkali combination. The clay substrate and basic alkali salt may be combined in a solid-solid heterogeneous mixture and followed by introduction of the amine liquid. Alternatively, an alkaline solution may be blended with the amine solution prior to contacting the clay substrate. The clay-alkali-amine CO.sub.2 sorbent is particularly advantageous for low temperature CO.sub.2 removal cycles in a gas stream having a CO.sub.2 concentration less than around 2000 ppm and an oxygen concentration around 21%, such as air. Results are presented illustrating the performance of the clay-alkali-amine CO.sub.2 sorbent compared to a clay-amine sorbent lacking the alkali inclusion.

  6. Formation of CuxS Layers on Polypropylene Sulfurized by Molten Sulfur

    Directory of Open Access Journals (Sweden)

    Rasa ALABURDAITĖ

    2011-11-01

    Full Text Available The processes of formation of electrically conductive layers of copper sulfides CuxS by the sorption-diffusion method on polypropylene (PP using molten sulfur as sulfurizing agent was investigated. The amount of sorbed sulfur increased with the increase of the duration of treatment. Copper sulfide layers were formed on the surface of polypropylene after the treatment of sulfurized polymer with Cu(II/I salt solution. The amount of copper sulfide in layer increased with the increase of treatment duration in copper salt solution. XRD spectra of PP films treated for 3 min with molten sulfur and then with Cu(II/I salt solution for the different time showed that the copper sulfide phases, mostly digenite, Cu2-xS and a-chalcocite, Cu2S were formed in the layers. Electromotive force measurement results confirmed the composition of formed CuxS layers on PP. The phase composition of layers also changed after the annealing. The value of electrical resistance of copper sulfide layers on PP varied from 20 W/cm2 to 80 W/cm2 and after annealing at 80 °C - in the interval of 10 W/cm2 - 60 W/cm2.http://dx.doi.org/10.5755/j01.ms.17.4.776

  7. Utilization of two invasive free-floating aquatic plants (Pistia stratiotes and Eichhornia crassipes) as sorbents for oil removal.

    Science.gov (United States)

    Yang, Xunan; Chen, Shanshan; Zhang, Renduo

    2014-01-01

    Free-floating aquatic plants Pistia stratiotes and Eichhornia crassipes are well-known invasive species in the tropics and subtropics. The aim of this study was to utilize the plants as cost-effective and environmentally friendly oil sorbents. Multilevel wrinkle structure of P. stratiotes leaf (PL), rough surface of E. crassipes leaf (EL), and box structure of E. crassipes stalk (ES) were observed using the scanning electron microscope. The natural hydrophobic structures and capillary rise tests supported the idea to use P. stratiotes and E. crassipes as oil sorbents. Experiments indicated that the oil sorption by the plants was a fast process. The maximum sorption capacities for different oils reached 5.1-7.6, 3.1-4.8, and 10.6-11.7 g of oil per gram of sorbent for PL, EL, and ES, respectively. In the range of 5-35 °C, the sorption capacities of the plants were not significantly different. These results suggest that the plants can be used as efficient oil sorbents.

  8. Waste treatment and immobilization technologies involving inorganic sorbents. Final report of a co-ordinated research programme 1992-1996

    International Nuclear Information System (INIS)

    1997-06-01

    A Coordinated Research Programme (CRP) for the application of inorganic sorbents in liquid waste treatment and immobilization was initiated by the IAEA in 1992. The results of this CRP are presented in this report. Fifteen institutions from fourteen countries were involved in this programme. The framework of this CRP was: (1) to conduct fundamental studies on sorbent structure and sorption mechanism; (2) to obtain thermodynamic and kinetic data of the treatment process; (3) to define sorption mechanism of radionuclides on different soils; (4) to identify sorbents appropriate for treatment of liquid waste streams; (5) to develop standard tests to be able to compare results of different groups of investigations. Refs, figs, tabs

  9. Analysis of sulfur-iodine thermochemical cycle for solar hydrogen production. Part 1: decomposition of sulfuric acid

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Cunping; T-Raissi, Ali [Central Florida Univ., Florida Solar Energy Center, Cocoa, FL (United States)

    2005-05-01

    The sulfur-iodine (S-I) thermochemical water splitting cycle is one of the most studied cycles for hydrogen (H{sub 2}) production. S-I cycle consists of four sections: (I) acid production and separation and oxygen purification, (II) sulfuric acid concentration and decomposition, (III) hydroiodic acid (HI) concentration, and (IV) HI decomposition and H{sub 2} purification. Section II of the cycle is an endothermic reaction driven by the heat input from a high temperature source. Analysis of the S-I cycle in the past thirty years have been focused mostly on the utilization of nuclear power as the high temperature heat source for the sulfuric acid decomposition step. Thermodynamic as well as kinetic considerations indicate that both the extent and rate of sulfuric acid decomposition can be improved at very high temperatures (in excess of 1000 deg C) available only from solar concentrators. The beneficial effect of high temperature solar heat for decomposition of sulfuric acid in the S-I cycle is described in this paper. We used Aspen Technologies' HYSYS chemical process simulator (CPS) to develop flowsheets for sulfuric acid (H{sub 2}SO{sub 4}) decomposition that include all mass and heat balances. Based on the HYSYS analyses, two new process flowsheets were developed. These new sulfuric acid decomposition processes are simpler and more stable than previous processes and yield higher conversion efficiencies for the sulfuric acid decomposition and sulfur dioxide and oxygen formation. (Author)

  10. High Mass-Loading of Sulfur-Based Cathode Composites and Polysulfides Stabilization for Rechargeable Lithium/Sulfur Batteries

    International Nuclear Information System (INIS)

    Hara, Toru; Konarov, Aishuak; Mentbayeva, Almagul; Kurmanbayeva, Indira; Bakenov, Zhumabay

    2015-01-01

    Although sulfur has a high theoretical gravimetric capacity, 1672 mAh/g, its insulating nature requires a large amount of conducting additives: this tends to result in a low mass-loading of active material (sulfur), and thereby, a lower capacity than expected. Therefore, an optimal choice of conducting agents and of the method for sulfur/conducting-agent integration is critically important. In this paper, we report that the areal capacity of 4.9 mAh/cm 2 was achieved at sulfur mass loading of 4.1 mg/cm 2 by casting sulfur/polyacrylonitrile/ketjenblack (S/PAN/KB) cathode composite into carbon fiber paper. This is the highest value among published/reported ones even though it does not contain expensive nanosized carbon materials such as carbon nanotubes, graphene, or graphene derivatives, and competitive enough with the conventional LiCoO 2 -based cathodes (e.g., LiCoO 2 , <20 mg/cm 2 corresponding to <2.8 mAh/cm 2 ). Furthermore, the combination of sulfur/PAN-based composite and PAN-based carbon fiber paper enabled the sulfur-based composite to be used even in carbonate-based electrolyte solution that many lithium/sulfur battery researchers avoid the use of it because of severer irreversible active material loss than in electrolyte solutions without carbonate-based solutions, and even at the highest mass-loading ever reported (the more sulfur is loaded, the more decomposed sulfides deposit at an anode surface).

  11. Developing porous carbon with dihydrogen phosphate groups as sulfur host for high performance lithium sulfur batteries

    Science.gov (United States)

    Cui, Yanhui; Zhang, Qi; Wu, Junwei; Liang, Xiao; Baker, Andrew P.; Qu, Deyang; Zhang, Hui; Zhang, Huayu; Zhang, Xinhe

    2018-02-01

    Carbon matrix (CM) derived from biomass is low cost and easily mass produced, showing great potential as sulfur host for lithium sulfur batteries. In this paper we report on a dihydrogen phosphate modified CM (PCM-650) prepared from luffa sponge (luffa acutangula) by phosphoric acid treatment. The phosphoric acid not only increases the surface area of the PCM-650, but also introduces dihydrogen phosphate onto PCM-650 (2.28 at% P). Sulfur impregnated (63.6 wt%) PCM-650/S, in comparison with samples with less dihydrogen phosphate LPCM-650/S, shows a significant performance improvement. XPS analysis is conducted for sulfur at different stages, including sulfur (undischarged), polysulfides (discharge to 2.1 V) and short chain sulfides (discharge to 1.7 V). The results consistently show chemical shifts for S2p in PCM-650, suggesting an enhanced adsorption effect. Furthermore, density functional theory (DFT) calculations is used to clarify the molecular binding: carbon/sulfur (0.86 eV), carbon/Li2S (0.3 eV), CH3-O-PO3H2/sulfur (1.24 eV), and CH3-O-PO3H2/Li2S (1.81 eV). It shows that dihydrogen phosphate group can significantly enhance the binding with sulfur and sulfide, consistent with XPS results. Consequently a CM functionalised with dihydrogen phosphate shows great potential as the sulfur host in a Li-S battery.

  12. Effect of commercial activated carbons in sulfur cathodes on the electrochemical properties of lithium/sulfur batteries

    Energy Technology Data Exchange (ETDEWEB)

    Park, Jin-Woo; Kim, Icpyo [School of Materials Science and Engineering, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828 (Korea, Republic of); Kim, Ki-Won; Nam, Tae-Hyun; Cho, Kwon-Koo; Ahn, Jou-Hyeon [Department of Materials Engineering and Convergence Technology, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828 (Korea, Republic of); Ryu, Ho-Suk [Department of Material and Energy Engineering, Gyeongwoon University, 730, Gangdong-ro, Sandong-myeon, Gumi, Gyeongbuk, 39160 (Korea, Republic of); Ahn, Hyo-Jun, E-mail: ahj@gnu.ac.kr [School of Materials Science and Engineering, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828 (Korea, Republic of); Department of Materials Engineering and Convergence Technology, Gyeongsang National University, 501 Jinju-daero, Jinju, Gyeongnam 52828 (Korea, Republic of)

    2016-10-15

    Highlights: • The sulfur/activated carbon composite is fabricated using commercial activated carbons. • The sulfur/activated carbon composite with coal shows the best performance. • The Li/S battery has capacities of 1240 mAh g{sup −1} at 1 C and 567 mAh g{sup −1} at 10 C. - Abstract: We prepared sulfur/active carbon composites via a simple solution-based process using the following commercial activated carbon-based materials: coal, coconut shells, and sawdust. Although elemental sulfur was not detected in any of the sulfur/activated carbon composites based on Thermogravimetric analysis, X-ray diffraction, and Raman spectroscopy, Energy-dispersive X-ray spectroscopy results confirmed its presence in the activated carbon. These results indicate that sulfur was successfully impregnated in the activated carbon and that all of the activated carbons acted as sulfur reservoirs. The sulfur/activated carbon composite cathode using coal exhibited the highest discharge capacity and best rate capability. The first discharge capacity at 1 C (1.672 A g{sup −1}) was 1240 mAh g{sup −1}, and a large reversible capacity of 567 mAh g{sup −1} was observed at 10 C (16.72 A g{sup −1}).

  13. Sulfur isotope in nature. Determination of sulfur isotope ratios in coal and petroleum by mass spectrometry

    International Nuclear Information System (INIS)

    Derda, M.

    1999-01-01

    Elementary sulfur or in chemical compounds is one of the elements widespread in the earth's crust and biosphere. Its participation in earth's crust amounts to 0.26 % by weight. Measurement of isotope composition of natural samples can deliver many information about origin, creation and transformation ranges of rocks and minerals. Sulfur isotope ratio contained in minerals is variable and for this reason investigation of isotope sulfur composition can deliver useful information about the geochemistry of each component. Therefore in the investigated sample it is necessary to determine not only the content of sulfur but also the isotope composition of each component. Differentiation of contents of sulfur-34 in natural sulfur compounds can reach up to 110 per mile. So large divergences can be explained by a kinetic effect or by bacterial reduction of sulphates. In this report a wide review of the results of investigations of isotope sulfur compositions in coal and petroleum are presented as well as the methods for the preparation of samples for mass spectrometry analysis are proposed. (author)

  14. A novel molybdenum disulfide nanosheet self-assembled flower-like monolithic sorbent for solid-phase extraction with high efficiency and long service life.

    Science.gov (United States)

    Ran, Fanpeng; Liu, Hongmei; Wang, Xiaoqi; Guo, Yong

    2017-07-21

    A novel material consisting of molybdenum disulfide (MoS 2 ) nanosheet that self-assemble into flower-like microspheres which aggregate to form a monolithic matrix with a micro or nano-scaled mesopore structure was successfully synthesized and used as an efficient sorbent for solid-phase extraction (SPE) due to its large specific adsorption area and good stability. The extraction properties of the as-prepared sorbent were evaluated by high-performance liquid chromatography with variable wavelength detection (HPLC-VWD) by analyzing four flavonoids (apigenin, quercetin, luteolin, and kaempferol). Under optimal conditions, the LODs and LOQs were found to be in the ranges of 0.1-0.25 and 0.4-0.5μgL -1 , respectively, and wide linear ranges were obtained with correlation coefficients (R) ranging from 0.9991 to 0.9996. Compared with commercial C18 and Alumina-N sorbents, the as-prepared sorbent showed high extraction efficiency at different concentrations of flavonoids. After 100 uses, the extraction ability of the self-assembled MoS 2 nanosheet monolithic sorbent had no evident decline, denoting a long service life. Finally, the SPE-HPLC-VWD method using the as-prepared sorbent was applied to flavonoid analysis in beverage samples with satisfactory results. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Advanced Sulfur Cathode Enabled by Highly Crumpled Nitrogen-Doped Graphene Sheets for High-Energy-Density Lithium-Sulfur Batteries.

    Science.gov (United States)

    Song, Jiangxuan; Yu, Zhaoxin; Gordin, Mikhail L; Wang, Donghai

    2016-02-10

    Herein, we report a synthesis of highly crumpled nitrogen-doped graphene sheets with ultrahigh pore volume (5.4 cm(3)/g) via a simple thermally induced expansion strategy in absence of any templates. The wrinkled graphene sheets are interwoven rather than stacked, enabling rich nitrogen-containing active sites. Benefiting from the unique pore structure and nitrogen-doping induced strong polysulfide adsorption ability, lithium-sulfur battery cells using these wrinkled graphene sheets as both sulfur host and interlayer achieved a high capacity of ∼1000 mAh/g and exceptional cycling stability even at high sulfur content (≥80 wt %) and sulfur loading (5 mg sulfur/cm(2)). The high specific capacity together with the high sulfur loading push the areal capacity of sulfur cathodes to ∼5 mAh/cm(2), which is outstanding compared to other recently developed sulfur cathodes and ideal for practical applications.

  16. Effects of sulfur on lead partitioning during sludge incineration based on experiments and thermodynamic calculations.

    Science.gov (United States)

    Liu, Jing-yong; Huang, Shu-jie; Sun, Shui-yu; Ning, Xun-an; He, Rui-zhe; Li, Xiao-ming; Chen, Tao; Luo, Guang-qian; Xie, Wu-ming; Wang, Yu-Jie; Zhuo, Zhong-xu; Fu, Jie-wen

    2015-04-01

    Experiments in a tubular furnace reactor and thermodynamic equilibrium calculations were conducted to investigate the impact of sulfur compounds on the migration of lead (Pb) during sludge incineration. Representative samples of typical sludge with and without the addition of sulfur compounds were combusted at 850 °C, and the partitioning of Pb in the solid phase (bottom ash) and gas phase (fly ash and flue gas) was quantified. The results indicate that three types of sulfur compounds (S, Na2S and Na2SO4) added to the sludge could facilitate the volatilization of Pb in the gas phase (fly ash and flue gas) into metal sulfates displacing its sulfides and some of its oxides. The effect of promoting Pb volatilization by adding Na2SO4 and Na2S was superior to that of the addition of S. In bottom ash, different metallic sulfides were found in the forms of lead sulfide, aluminosilicate minerals, and polymetallic-sulfides, which were minimally volatilized. The chemical equilibrium calculations indicated that sulfur stabilizes Pb in the form of PbSO4(s) at low temperatures (incineration process mainly depended on the gas phase reaction, the surface reaction, the volatilization of products, and the concentration of Si, Ca and Al-containing compounds in the sludge. These findings provide useful information for understanding the partitioning behavior of Pb, facilitating the development of strategies to control the volatilization of Pb during sludge incineration. Copyright © 2014 Elsevier Ltd. All rights reserved.

  17. Computational Modeling of Mixed Solids for CO2 CaptureSorbents

    Energy Technology Data Exchange (ETDEWEB)

    Duan, Yuhua

    2015-01-01

    Since current technologies for capturing CO2 to fight global climate change are still too energy intensive, there is a critical need for development of new materials that can capture CO2 reversibly with acceptable energy costs. Accordingly, solid sorbents have been proposed to be used for CO2 capture applications through a reversible chemical transformation. By combining thermodynamic database mining with first principles density functional theory and phonon lattice dynamics calculations, a theoretical screening methodology to identify the most promising CO2 sorbent candidates from the vast array of possible solid materials has been proposed and validated. The calculated thermodynamic properties of different classes of solid materials versus temperature and pressure changes were further used to evaluate the equilibrium properties for the CO2 adsorption/desorption cycles. According to the requirements imposed by the pre- and post- combustion technologies and based on our calculated thermodynamic properties for the CO2 capture reactions by the solids of interest, we were able to screen only those solid materials for which lower capture energy costs are expected at the desired pressure and temperature conditions. Only those selected CO2 sorbent candidates were further considered for experimental validations. The ab initio thermodynamic technique has the advantage of identifying thermodynamic properties of CO2 capture reactions without any experimental input beyond crystallographic structural information of the solid phases involved. Such methodology not only can be used to search for good candidates from existing database of solid materials, but also can provide some guidelines for synthesis new materials. In this presentation, we apply our screening methodology to mixing solid systems to adjust the turnover temperature to help on developing CO2 capture Technologies.

  18. Investigation and demonstration of dry carbon-based sorbent injection for mercury control. Quarterly technical report, July 1, 1996--September 31, 1996

    Energy Technology Data Exchange (ETDEWEB)

    Hunt, T.; Sjostrom, S.; Smith, J. [and others

    1996-11-06

    The overall objective of this two phase program is to investigate the use of dry carbon-based sorbents for mercury control. This information is important to the utility industry in anticipation of pending regulations. During Phase I, a bench-scale field test device that can be configured as an electrostatic precipitator, a pulse-jet baghouse, or a reverse-gas baghouse has been designed, built and integrated with an existing pilot-scale facility at PSCo`s Comanche Station. Up to three candidate sorbents will be injected into the flue gas stream upstream of the test device to and mercury concentration measurements will be made to determine the mercury removal efficiency for each sorbent. During the Phase II effort, component integration for the most promising dry sorbent technology shall be tested at the 5000 acfm pilot-scale.

  19. Clues to early diagenetic sulfurization processes from mild chemical cleavage of labile sulfur-rich geomacromolecules

    Science.gov (United States)

    Adam, P.; Schneckenburger, P.; Schaeffer, P.; Albrecht, P.

    2000-10-01

    Macromolecular fractions, isolated from the solvent extract of sulfur-rich Recent (Siders Pond, USA; Lake Cadagno, Switzerland; Walvis Bay, Namibia) and immature sediments (Gibellina, Messinian of Sicily; Vena del Gesso, Messinian of Italy), were investigated by chemical degradation using sodium ethanethiolate/methyliodide. This mild reagent which cleaves polysulfide bonds to yield methylsulfides has the advantage over other methods of leaving intact other functionalities (like double bonds) and preserving sulfur atoms at their incorporation site. The method is, therefore, well-suited to the molecular level investigation of sulfur-rich macromolecules from Recent sediments containing highly functionalized polysulfide-bound subunits. In Recent anoxic sulfur-rich sediments, the release of various methylthioethers clearly demonstrates that intermolecular sulfurization of organic matter does occur at the earliest stages of diagenesis. Steroids and phytane derivatives are the major sulfurized lipids, a feature also observed in more mature sulfur-rich sediments. Several phytene derivatives, such as cis and trans 1-methylthiophyt-2-enes, as well as methylthiosteroids, including 5α- and 5β-3-(methylthio)-cholest-2-enes, were identified by comparison with synthesized standards. Steroid methylthioenolethers are released from polysulfide-bound steroid enethiols present in the macromolecular fractions. The latter, which correspond to thioketones, can be considered as intermediates in the reductive sulfurization pathway leading from steroid ketones to polysulfide-bound saturated steroid skeletons and are characterized for the first time in the present study. Thus, it could be shown that the major part of the polysulfide-bound lipids occurring in Recent sediments is apparently the result of sulfurization processes affecting carbonyls (aldehydes and ketones). The unsaturated methylthioethers obtained from Recent sediments were not present in more mature evaporitic samples, which

  20. Poly(ethyleneimine) infused and functionalized Torlon®-silica hollow fiber sorbents for post-combustion CO2 capture

    KAUST Repository

    Li, Fuyue Stephanie

    2014-03-01

    Organic-inorganic hybrid materials functionalized with amine-containing reagents are emerging as an important class of materials for capturing carbon dioxide from flue gas. Polymeric silica hollow fiber sorbents are fabricated through the proven dry-jet/wet-quench spinning process. In our study, a new technique for functionalizing polymeric silica hollow fiber sorbents with poly(ethyleneimine), followed by a post-spinning infusion step was studied. This two step process introduces a sufficient amount of poly(ethyleneimine) to the polymeric silica hybrid material support to improve the CO2 sorption capacity due to the added amine groups. The poly(ethyleneimine) infused and functionalized hollow fiber sorbents are also characterized by a thermal gravimetric analyzer (TGA) to assess their CO2 sorption capacities. © 2014 Elsevier Ltd. All rights reserved.

  1. A sulfur host based on titanium monoxide@carbon hollow spheres for advanced lithium-sulfur batteries.

    Science.gov (United States)

    Li, Zhen; Zhang, Jintao; Guan, Buyuan; Wang, Da; Liu, Li-Min; Lou, Xiong Wen David

    2016-10-20

    Lithium-sulfur batteries show advantages for next-generation electrical energy storage due to their high energy density and cost effectiveness. Enhancing the conductivity of the sulfur cathode and moderating the dissolution of lithium polysulfides are two key factors for the success of lithium-sulfur batteries. Here we report a sulfur host that overcomes both obstacles at once. With inherent metallic conductivity and strong adsorption capability for lithium-polysulfides, titanium monoxide@carbon hollow nanospheres can not only generate sufficient electrical contact to the insulating sulfur for high capacity, but also effectively confine lithium-polysulfides for prolonged cycle life. Additionally, the designed composite cathode further maximizes the lithium-polysulfide restriction capability by using the polar shells to prevent their outward diffusion, which avoids the need for chemically bonding all lithium-polysulfides on the surfaces of polar particles.

  2. Synthesis and application of surface-imprinted activated carbon sorbent for solid-phase extraction and determination of copper (II)

    Science.gov (United States)

    Li, Zhenhua; Li, Jingwen; Wang, Yanbin; Wei, Yajun

    2014-01-01

    A new Cu(II)-imprinted amino-functionalized activated carbon sorbent was prepared by a surface imprinting technique for selective solid-phase extraction (SPE) of Cu(II) prior to its determination by inductively coupled plasma atomic emission spectrometry (ICP-AES). Experimental conditions for effective adsorption of Cu(II) were optimized with respect to different experimental parameters using static and dynamic procedures in detail. Compared with non-imprinted sorbent, the ion-imprinted sorbent had higher selectivity and adsorption capacity for Cu(II). The maximum static adsorption capacity of the ion-imprinted and non-imprinted sorbent for Cu(II) was 26.71 and 6.86 mg g-1, respectively. The relatively selectivity factor values (αr) of Cu(II)/Zn(II), Cu(II)/Ni(II), Cu(II)/Co(II) and Cu(II)/Pb(II) were 166.16, 50.77, 72.26 and 175.77, respectively, which were greater than 1. Complete elution of the adsorbed Cu(II) from Cu(II)-imprinted sorbent was carried out using 2 mL of 0.1 mol L-1 EDTA solution. The relative standard deviation of the method was 2.4% for eleven replicate determinations. The method was validated for the analysis by two certified reference materials (GBW 08301, GBW 08303), the results obtained is in good agreement with standard values. The developed method was also successfully applied to the determination of trace copper in natural water samples with satisfactory results.

  3. Magnetite impregnation effects on the sorbent properties of activated carbons and biochars.

    Science.gov (United States)

    Han, Zhantao; Sani, Badruddeen; Mrozik, Wojciech; Obst, Martin; Beckingham, Barbara; Karapanagioti, Hrissi K; Werner, David

    2015-03-01

    This paper discusses the sorbent properties of magnetic activated carbons and biochars produced by wet impregnation with iron oxides. The sorbents had magnetic susceptibilities consistent with theoretical predictions for carbon-magnetite composites. The high BET surface areas of the activated carbons were preserved in the synthesis, and enhanced for one low surface area biochar by dissolving carbonates. Magnetization decreased the point of zero charge. Organic compound sorption correlated strongly with BET surface areas for the pristine and magnetized materials, while metal cation sorption did not show such a correlation. Strong sorption of the hydrophobic organic contaminant phenanthrene to the activated carbon or biochar surfaces was maintained following magnetite impregnation, while phenol sorption was diminished, probably due to enhanced carbon oxidation. Copper, zinc and lead sorption to the activated carbons and biochars was unchanged or slightly enhanced by the magnetization, and iron oxides also contributed to the composite metal sorption capacity. While a magnetic biochar with 219 ± 3.7 m(2)/g surface area nearly reached the very strong organic pollutant binding capacity of the two magnetic activated carbons, a magnetic biochar with 68 ± 2.8 m(2)/g surface area was the best metal sorbent. Magnetic biochars thus hold promise as more sustainable alternatives to coal-derived magnetic activated carbons. Copyright © 2014 Elsevier Ltd. All rights reserved.

  4. Localization of gastrointestinal bleeding: superiority of 99mTc sulfur colloid compared with angiography

    International Nuclear Information System (INIS)

    Alavi, A.; Ring, E.J.

    1981-01-01

    Preliminary experience with technetium-99m sulfur colloid scintigraphy in 43 patients with lower gastrointestinal bleeding is described. Within minutes of the intravenous introduction of the radiopharmaceutical, a fraction of the injected activity extravasates at the bleeding site and is eliminated from the circulation. Because of rapid clearance of the radiopharmaceutical from the vascular pool by the reticuloendothelial system, a contrast develops between the site of bleeding and surrounding background. Based on animal experiments, bleeding rates as low as 0.05-0.1 ml/min can be detected with this technique. The sensitivity of this technique in the detection of the site of hemorrhage is significantly higher than arteriography or other techniques that use radioactive blood pool indicators. In this study all patients underwent both scintigraphy and arteriography within several hours. In 20 patients with negative scintigrams, arteriography showed no evidence of bleeding. In the other 23 patients with scintigraphic evidence of hemorrhage, arteriograms were positive for bleeding only in 10. In 19 of the 23 patients, a cause for bleeding was eventually established by other means. This technique appears to offer a simple, practical, and reliable approach to the evaluation of patients with lower gastrointestinal bleeding

  5. Theoretical evaluation on selective adsorption characteristics of alkali metal-based sorbents for gaseous oxidized mercury.

    Science.gov (United States)

    Tang, Hongjian; Duan, Yufeng; Zhu, Chun; Cai, Tianyi; Li, Chunfeng; Cai, Liang

    2017-10-01

    Alkali metal-based sorbents are potential for oxidized mercury (Hg 2+ ) selective adsorption but show hardly effect to elemental mercury (Hg 0 ) in flue gas. Density functional theory (DFT) was employed to investigate the Hg 0 and HgCl 2 adsorption mechanism over alkali metal-based sorbents, including calcium oxide (CaO), magnesium oxide (MgO), potassium chloride (KCl) and sodium chloride (NaCl). Hg 0 was found to weakly interact with CaO (001), MgO (001), KCl (001) and NaCl (001) surfaces while HgCl 2 was effectively adsorbed on top-O and top-Cl sites. Charge transfer and bond population were calculated to discuss the covalency and ionicity of HgCl 2 bonding with the adsorption sites. The partial density of states (PDOS) analysis manifests that HgCl 2 strongly interacts with surface sites through the orbital hybridizations between Hg and top O or Cl. Frontier molecular orbital (FMO) energy and Mulliken electronegativity are introduced as the quantitative criteria to evaluate the reactivity of mercury species and alkali metal-based sorbents. HgCl 2 is identified as a Lewis acid and more reactive than Hg 0 . The Lewis basicity of the four alkali metal-based sorbents is predicted as the increasing order: NaCl < MgO < KCl < CaO, in consistence with the trend of HgCl 2 adsorption energies. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. A decontamination system for chemical weapons agents using a liquid solution on a solid sorbent.

    Science.gov (United States)

    Waysbort, Daniel; McGarvey, David J; Creasy, William R; Morrissey, Kevin M; Hendrickson, David M; Durst, H Dupont

    2009-01-30

    A decontamination system for chemical warfare agents was developed and tested that combines a liquid decontamination reagent solution with solid sorbent particles. The components have fewer safety and environmental concerns than traditional chlorine bleach-based products or highly caustic solutions. The liquid solution, based on Decon Greentrade mark, has hydrogen peroxide and a carbonate buffer as active ingredients. The best solid sorbents were found to be a copolymer of ethylene glycol dimethacrylate and n-lauryl methacrylate (Polytrap 6603 Adsorber); or an allyl methacrylate cross-linked polymer (Poly-Pore E200 Adsorber). These solids are human and environmentally friendly and are commonly used in cosmetics. The decontaminant system was tested for reactivity with pinacolyl methylphosphonofluoridate (Soman, GD), bis(2-chloroethyl)sulfide (Mustard, HD), and S-(2-diisopropylaminoethyl) O-ethyl methylphosphonothioate (VX) by using NMR Spectroscopy. Molybdate ion (MoO(4)(-2)) was added to the decontaminant to catalyze the oxidation of HD. The molybdate ion provided a color change from pink to white when the oxidizing capacity of the system was exhausted. The decontaminant was effective for ratios of agent to decontaminant of up to 1:50 for VX (t(1/2) decontamination solution were measured to show that the sorbent decreased the vapor concentration of GD. The E200 sorbent had the additional advantage of absorbing aqueous decontamination solution without the addition of an organic co-solvent such as isopropanol, but the rate depended strongly on mixing for HD.

  7. Diatomaceous earth and activated bauxite used as granular sorbents for the removal of sodium chloride vapor from hot flue gas

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S.H.D.; Swift, W.M.; Johnson, I.

    1980-01-01

    Diatomaceous earth and activated bauxite were tested as granular sorbents for use as filter media in granular-bed filters for the removal of gaseous alkali metal compounds from the hot (800/sup 0/C) flue gas of PFBC. Tests were performed at atmospheric pressure, using NaCl vapor transported in relatively dry simulated flue gas of PFBC. Either a fixed-bed combustor or a high-temperature sorption test rig was used. The effects of sorbent bed temperature, superficial gas velocity, gas hourly space velocity, and NaCl-vapor concentration in flue gas on the sorption behavior of these two sorbents and their ultimate sorption capacities were determined. Both diatomaceous earth and activated bauxite were found to be very effective in removing NaCl vapor from flue gas. Preliminary cost evaluations showed that they are economically attractive as granular sorbents for cleaning alkali vapor from simulated flue gas.

  8. Core-in-shell sorbent for hot coal gas desulfurization

    Science.gov (United States)

    Wheelock, Thomas D.; Akiti, Jr., Tetteh T.

    2004-02-10

    A core-in-shell sorbent is described herein. The core is reactive to the compounds of interest, and is preferably calcium-based, such as limestone for hot gas desulfurization. The shell is a porous protective layer, preferably inert, which allows the reactive core to remove the desired compounds while maintaining the desired physical characteristics to withstand the conditions of use.

  9. A composite of hollow carbon nanospheres and sulfur-rich polymers for lithium-sulfur batteries

    Science.gov (United States)

    Zeng, Shao-Zhong; Yao, Yuechao; Zeng, Xierong; He, Qianjun; Zheng, Xianfeng; Chen, Shuangshuang; Tu, Wenxuan; Zou, Jizhao

    2017-07-01

    Lithium-sulfur batteries are the most promising candidates for future high-energy applications because of the unparalleled capacity of sulfur (1675 mAh g-1). However, lithium-sulfur batteries have limited cycle life and rate capability due to the dissolution of polysulfides and the extremely low electronic conductivity of sulfur. To solve these issues, various porous carbons including hollow carbon nanospheres (HCNs) have been used for improving the conductivity. However, these methods still suffer from polysulfides dissolution/loss owing to their weak physical adsorption to polysulfides. Herein, we introduced a covalent grafting route to composite the HCNs and the vulcanized trithiocyanuric acid (TTCA). The composite exhibits a high loading of the vulcanized TTCA by the HCNs with high surface area and large pore volume, and covalent bonds to sulfur, effectively depressing the dissolution of polysulfides. The first discharge capacity of the composite reaches 1430 mAh g-1 at 0.1 C and 1227 mAh g-1 at 0.2 C.

  10. The study of sorption of cesium radionuclides by 'T-55' ferrocyanide sorbent from various types of liquid radioactive wastes

    International Nuclear Information System (INIS)

    Semenischev, V.S.; Voronina, A.V.; Bykov, A.A.

    2013-01-01

    The sorption of caesium by T-55 sorbent from different types of liquid radioactive wastes is studied. It is shown that the sorbent can be used for extraction of cesium from high level acidic and saline solutions and also for decontamination of caesium contaminated waters containing surfactants and EDTA. (author)

  11. Red soil as a regenerable sorbent for high temperature removal of hydrogen sulfide from coal gas

    International Nuclear Information System (INIS)

    Ko, T.-H.; Chu Hsin; Lin, H.-P.; Peng, C.-Y.

    2006-01-01

    In this study, hydrogen sulfide (H 2 S) was removed from coal gas by red soil under high temperature in a fixed-bed reactor. Red soil powders were collected from the northern, center and southern of Taiwan. They were characterized by XRPD, porosity analysis and DCB chemical analysis. Results show that the greater sulfur content of LP red soils is attributed to the higher free iron oxides and suitable sulfidation temperature is around 773 K. High temperature has a negative effect for use red soil as a desulfurization sorbent due to thermodynamic limitation in a reduction atmosphere. During 10 cycles of regeneration, after the first cycle the red soil remained stable with a breakthrough time between 31 and 36 min. Hydrogen adversely affects sulfidation reaction, whereas CO exhibits a positive effect due to a water-shift reaction. COS was formed during the sulfidation stage and this was attributed to the reaction of H 2 S and CO. Results of XRPD indicated that, hematite is the dominant active species in fresh red soil and iron sulfide (FeS) is a product of the reaction between hematite and hydrogen sulfide in red soils. The spinel phase FeAl 2 O 4 was found during regeneration, moreover, the amount of free iron oxides decreased after regeneration indicating the some of the free iron oxide formed a spinel phase, further reducting the overall desulfurization efficiency

  12. Preparation of an aminopropyl imidazole-modified silica gel as a sorbent for solid-phase extraction of carboxylic acid compounds and polycyclic aromatic hydrocarbons.

    Science.gov (United States)

    Wang, Na; Guo, Yong; Wang, Licheng; Liang, Xiaojing; Liu, Shujuan; Jiang, Shengxiang

    2014-05-21

    In this paper, a kind of aminopropyl imidazole-modified silica sorbent was synthesized and used as a solid-phase extraction (SPE) sorbent for the determination of carboxylic acid compounds and polycyclic aromatic hydrocarbons (PAHs). The resultant aminopropyl imidazole-modified silica sorbent was characterized by Fourier transform infrared spectroscopy (FT-IR) and elemental analysis (EA) to ensure the successful binding of aminopropyl imidazole on the surface of silica gel. Then the aminopropyl imidazole-modified silica sorbent served as a SPE sorbent for the enrichment of carboxylic acid compounds and PAHs. The new sorbent exhibited high extraction efficiency towards the tested compounds and the results show that such a sorbent can offer multiple intermolecular interactions: electrostatic, π-π, and hydrophobic interactions. Several parameters affecting the extraction recovery, such as the pH of sample solution, the pH of eluent, the solubility of eluent, the volume of eluent, and sample loading, were also investigated. Under the optimized conditions, the proposed method was applied to the analysis of four carboxylic acid compounds and four PAHs in environmental water samples. Good linearities were obtained for all the tested compounds with R(2) larger than 0.9903. The limits of detection were found to be in the range of 0.0065-0.5 μg L(-1). The recovery values of spiked river water samples were from 63.2% to 112.3% with relative standard deviations (RSDs) less than 10.1% (n = 4).

  13. Significant role of organic sulfur in supporting sedimentary sulfate reduction in low-sulfate environments

    Science.gov (United States)

    Fakhraee, Mojtaba; Li, Jiying; Katsev, Sergei

    2017-09-01

    Dissimilatory sulfate reduction (DSR) is a major carbon mineralization pathway in aquatic sediments, soils, and groundwater, which regulates the production of hydrogen sulfide and the mobilization rates of biologically important elements such as phosphorus and mercury. It has been widely assumed that water-column sulfate is the main sulfur source to fuel this reaction in sediments. While this assumption may be justified in high-sulfate environments such as modern seawater, we argue that in low-sulfate environments mineralization of organic sulfur compounds can be an important source of sulfate. Using a reaction-transport model, we investigate the production of sulfate from sulfur-containing organic matter for a range of environments. The results show that in low sulfate environments (50%) of sulfate reduction. In well-oxygenated systems, porewater sulfate profiles often exhibit sub-interface peaks so that sulfate fluxes are directed out of the sediment. Our measurements in Lake Superior, the world's largest lake, corroborate this conclusion: offshore sediments act as sources rather than sinks of sulfate for the water column, and sediment DSR is supported entirely by the in-sediment production of sulfate. Sulfate reduction rates are correlated to the depth of oxygen penetration and strongly regulated by the supply of reactive organic matter; rate co-regulation by sulfate availability becomes appreciable below 500 μM level. The results indicate the need to consider the mineralization of organic sulfur in the biogeochemical cycling in low-sulfate environments, including several of the world's largest freshwater bodies, deep subsurface, and possibly the sulfate-poor oceans of the Early Earth.

  14. Aircraft exhaust sulfur emissions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R C; Anderson, M R; Miake-Lye, R C; Kolb, C E [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics; Sorokin, A A; Buriko, Y I [Scientific Research Center ` Ecolen` , Moscow (Russian Federation)

    1998-12-31

    The extent to which fuel sulfur is converted to SO{sub 3} during combustion and the subsequent turbine flow in supersonic and subsonic aircraft engines is estimated numerically. The analysis is based on: a flamelet model with non-equilibrium sulfur chemistry for the combustor, and a one-dimensional, two-stream model with finite rate chemical kinetics for the turbine. The results indicate that between 2% and 10% of the fuel sulfur is emitted as SO{sub 3}. It is also shown that, for a high fuel sulfur mass loading, conversion in the turbine is limited by the level of atomic oxygen at the combustor exit, leading to higher SO{sub 2} oxidation efficiency at lower fuel sulfur loadings. While SO{sub 2} and SO{sub 3} are the primary oxidation products, the model results further indicate H{sub 2}SO{sub 4} levels on the order of 0.1 ppm for supersonic expansions through a divergent nozzle. This source of fully oxidized S(6) (SO{sub 3} + H{sub 2}SO{sub 4}) exceeds previously calculated S(6) levels due to oxidation of SO{sub 2} by OH in the exhaust plume outside the engine nozzle. (author) 26 refs.

  15. Aircraft exhaust sulfur emissions

    Energy Technology Data Exchange (ETDEWEB)

    Brown, R.C.; Anderson, M.R.; Miake-Lye, R.C.; Kolb, C.E. [Aerodyne Research, Inc., Billerica, MA (United States). Center for Chemical and Environmental Physics; Sorokin, A.A.; Buriko, Y.I. [Scientific Research Center `Ecolen`, Moscow (Russian Federation)

    1997-12-31

    The extent to which fuel sulfur is converted to SO{sub 3} during combustion and the subsequent turbine flow in supersonic and subsonic aircraft engines is estimated numerically. The analysis is based on: a flamelet model with non-equilibrium sulfur chemistry for the combustor, and a one-dimensional, two-stream model with finite rate chemical kinetics for the turbine. The results indicate that between 2% and 10% of the fuel sulfur is emitted as SO{sub 3}. It is also shown that, for a high fuel sulfur mass loading, conversion in the turbine is limited by the level of atomic oxygen at the combustor exit, leading to higher SO{sub 2} oxidation efficiency at lower fuel sulfur loadings. While SO{sub 2} and SO{sub 3} are the primary oxidation products, the model results further indicate H{sub 2}SO{sub 4} levels on the order of 0.1 ppm for supersonic expansions through a divergent nozzle. This source of fully oxidized S(6) (SO{sub 3} + H{sub 2}SO{sub 4}) exceeds previously calculated S(6) levels due to oxidation of SO{sub 2} by OH in the exhaust plume outside the engine nozzle. (author) 26 refs.

  16. Rubber Fruit Shell (Hevea brasiliensis) as bio sorbent to remove FFA (Free Fatty Acid) content in CPO (Crude Palm Oil)

    Science.gov (United States)

    Pandia, S.; Sinaga, M. S.; Masyithah, Z.; Husin, A.; Nurfadilla, S.; Fitriani; Sipahutar, B. K. S.

    2018-02-01

    This study aimed to discover the effectiveness of the shell of rubber fruit as bio sorbent for removing FFA (Free Fatty Acid) content in CPO (Crude Palm Oil). Methods used in this study were pretreatment, activation (carbonating and chemically) and adsorption process at room temperature. In the beginning, the shell of rubber fruit was cleaned and dried under the sun. Then the shell was cut for about 0.5 cm of length and carbonated in a furnace for 1h at 600°C. After that, they were crushed to pass through 140 meshes and activated using three variations of chemical such as 6 of HNO3, 6N of KOH and 6N of H3PO4 at certain ratio as 1:3, 1:4, and 1:5 (b/v). The adsorption process was carried out using bio sorbent with the highest iodine number in varying bio sorbent dosage and contact time. The highest iodine number was 913.680 mg/g and obtained at the ratio of bio sorbent to 6N of KOH as 1:5. The best removal of FFA content was 91.94% and at 1% bio sorbent dose and 30 min of contact time.

  17. Engineering metal (hydr)oxide sorbents for removal of arsenate and similar weak-acid oxyanion contaminants: A critical review with emphasis on factors governing sorption processes.

    Science.gov (United States)

    Hristovski, Kiril D; Markovski, Jasmina

    2017-11-15

    To create an integrative foundation for engineering of the next generation inexpensive sorbent systems, this critical review addresses the existing knowledge gap in factor/performance relationships between weak-acid oxyanion contaminants and metal (hydr)oxide sorbents. In-depth understanding of fundamental thermodynamics and kinetics mechanisms, material fabrication, and analytical and characterization techniques, is necessary to engineer sorbent that exhibit high capacity, selectivity, stability, durability and mass transport of contaminants under a wide range of operating and water matrix conditions requirements. From the perspective of thermodynamics and kinetics, this critical review examines the factors affecting sorbent performances and analyzes the existing research to elucidate future directions aimed at developing novel sorbents for removal of weak-acid oxyanion contaminants from water. Only sorbents that allow construction of simple and inexpensive water treatment systems adapted to overcome fiscal and technological barriers burdening small communities could pave the road for providing inexpensive potable water to millions of people. Novel sorbents, which exhibit (1) poor performances in realistic operating and water matrix conditions and/or (2) do not comply with the purely driven economics factors of production scalability or cost expectations, are predestined to never be commercialized. Copyright © 2017 Elsevier B.V. All rights reserved.

  18. Oxidation of inorganic sulfur compounds in acidophilic prokaryotes

    Energy Technology Data Exchange (ETDEWEB)

    Rohwerder, T.; Sand, W. [Universitaet Duisburg-Essen, Biofilm Centre, Aquatic Biotechnology, Duisburg (Germany)

    2007-07-15

    The oxidation of reduced inorganic sulfur compounds to sulfuric acid is of great importance for biohydrometallurgical technologies as well as the formation of acidic (below pH 3) and often heavy metal-contaminated environments. The use of elemental sulfur as an electron donor is the predominant energy-yielding process in acidic natural sulfur-rich biotopes but also at mining sites containing sulfidic ores. Contrary to its significant role in the global sulfur cycle and its biotechnological importance, the microbial fundamentals of acidophilic sulfur oxidation are only incompletely understood. Besides giving an overview of sulfur-oxidizing acidophiles, this review describes the so far known enzymatic reactions related to elemental sulfur oxidation in acidophilic bacteria and archaea. Although generally similar reactions are employed in both prokaryotic groups, the stoichiometry of the key enzymes is different. Bacteria oxidize elemental sulfur by a sulfur dioxygenase to sulfite whereas in archaea, a sulfur oxygenase reductase is used forming equal amounts of sulfide and sulfite. In both cases, the activation mechanism of elemental sulfur is not known but highly reactive linear sulfur forms are assumed to be the actual substrate. Inhibition as well as promotion of these biochemical steps is highly relevant in bioleaching operations. An efficient oxidation can prevent the formation of passivating sulfur layers. In other cases, a specific inhibition of sulfur biooxidation may be beneficial for reducing cooling and neutralization costs. In conclusion, the demand for a better knowledge of the biochemistry of sulfur-oxidizing acidophiles is underlined. (Abstract Copyright [2007], Wiley Periodicals, Inc.)

  19. Sandwich-like graphene-mesoporous carbon as sulfur host for enhanced lithium-sulfur batteries

    Science.gov (United States)

    Tian, Ting; Li, Bin; Zhu, Mengqi; Liu, Jianhua; Li, Songmei

    2017-10-01

    Graphene-mesoporous carbon/sulfur composites (G-MPC/S) were constructed by melt-infiltration of sulfur into graphene-mesoporous carbon which was synthesized by soft template method. The SEM and BET results of the graphene-mesoporous carbon show that the as-prepared sandwich-like G-MPC composites with a unique microporous-mesoporous structure had a high specific surface area of 554.164 m2 · g-1 and an average pore size of about 13 nm. The XRD analysis presents the existence of orthorhombic sulfur in the G-MPC/S composite, which indicates the complete infiltration of sulfur into the pores of the G-MPC. When the graphene-mesoporous carbon/surfur composites (G-MPC/S) with 53.9 wt.% sulfur loading were used as the cathode for lithium-sulfur (Li-S) batteries, it exhibited an outstanding electrochemical performance including excellent initial discharge specific capacity of 1393 mAh · g-1 at 0.1 °C, high cycle stability (731 mAh · g-1 at 200 cycles) and good rate performance (1038 mAh · g-1, 770 mAh · g-1, 518 mAh · g-1 and 377 mAh · g-1 at 0.1 °C, 0.2 °C, 0.5 °C and 1 °C, respectively), which suggested the important role of the G-MPC composite in providing more electrons and ions channels, in addition, the shuttle effect caused by the dissolved polysulfide was also suppressed.

  20. Regenerative process for removal of mercury and other heavy metals from gases containing H.sub.2 and/or CO

    Science.gov (United States)

    Jadhav, Raja A [Naperville, IL

    2009-07-07

    A method for removal of mercury from a gaseous stream containing the mercury, hydrogen and/or CO, and hydrogen sulfide and/or carbonyl sulfide in which a dispersed Cu-containing sorbent is contacted with the gaseous stream at a temperature in the range of about 25.degree. C. to about 300.degree. C. until the sorbent is spent. The spent sorbent is contacted with a desorbing gaseous stream at a temperature equal to or higher than the temperature at which the mercury adsorption is carried out, producing a regenerated sorbent and an exhaust gas comprising released mercury. The released mercury in the exhaust gas is captured using a high-capacity sorbent, such as sulfur-impregnated activated carbon, at a temperature less than about 100.degree. C. The regenerated sorbent may then be used to capture additional mercury from the mercury-containing gaseous stream.

  1. Biodegradation and ecotoxicity of soil contaminated by pentachlorophenol applying bioaugmentation and addition of sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Zuzana, S.; Katarina, D.; Livia, T. [Slovak Technical University Bratislava, Bratislava (Slovakia). Dept. of Biochemical Technology

    2009-02-15

    Biodegradation of pentachlorophenol (PCP) in soil by autochthonous microorganisms and in soil bioaugmented by the bacterial strain Comamonas testosteroni CCM 7530 was studied. Subsequent addition of organomineral complex (OMC) or lignite as possible sorbents for PCP immobilization has been investigated as well. The OMC was prepared from humic acids (HAs) isolated from lignite by binding them onto zeolite. Biodegradation of PCP and number of colony forming units (CFUs) were determined in the three types of soil, Chernozem, Fluvisol, and Regosol, freshly spiked with PCP and amended separately with tested sorbents. The enhancing effect of sorbent addition and bioaugmentation on PCP biodegradation depended mainly on the soil type and the initial PCP concentration. Microbial activity resulted in biotransformation of PCP into certain toxic substances, probably lower chlorinated phenols that are more soluble than PCP, and therefore more toxic to present biota. Therefore, it was necessary to monitor soil ecotoxicity during biodegradation. Addition of the OMC resulted in a more significant decrease of soil toxicity in comparison with addition of lignite. Lignite and OMC appear to be good traps for PCP with potential application in remediation technology.

  2. Parameters Influencing Sulfur Speciation in Environmental Samples Using Sulfur K-Edge X-Ray Absorption Near-Edge Structure

    Directory of Open Access Journals (Sweden)

    Siwatt Pongpiachan

    2012-01-01

    Full Text Available This paper aims to enhance the credibility of applying the sulfur K-edge XANES spectroscopy as an innovative “fingerprint” for characterizing environmental samples. The sensitivities of sulfur K-edge XANES spectra of ten sulfur compound standards detected by two different detectors, namely, Lytle detector (LyD and Germanium detector (GeD, were studied and compared. Further investigation on “self-absorption” effect revealed that the maximum sensitivities of sulfur K-edge XANES spectra were achieved when diluting sulfur compound standards with boron nitride (BN at the mixing ratio of 0.1%. The “particle-size” effect on sulfur K-edge XANES spectrum sensitivities was examined by comparing signal-to-noise ratios of total suspended particles (TSP and particulate matter of less than 10 millionths of a meter (PM10 collected at three major cities of Thailand. The analytical results have demonstrated that the signal-to-noise ratios of sulfur K-edge XANES spectra were positively correlated with sulfate content in aerosols and negatively connected with particle sizes. The combination of hierarchical cluster analysis (HCA and principal component analysis (PCA has proved that sulfur K-edge XANES spectrum can be used to characterize German terrestrial soils and Andaman coastal sediments. In addition, this study highlighted the capability of sulfur K-edge XANES spectra as an innovative “fingerprint” to distinguish tsunami backwash deposits (TBD from typical marine sediments (TMS.

  3. Pilot-Scale Evaluation of an Advanced Carbon Sorbent-Based Process for Post-Combustion Carbon Capture

    Energy Technology Data Exchange (ETDEWEB)

    Hornbostel, Marc [SRI International, Menlo Park, CA (United States)

    2016-09-01

    The overall objective of this project is to achieve the DOE’s goal to develop advanced CO2 capture and separation technologies that can realize at least 90% CO2 removal from flue gas steams produced at a pulverized coal (PC) power plant at a cost of less than $40/tonne of CO2 captured. The principal objective is to test a CO2 capture process that will reduce the parasitic plant load by using a CO2 capture sorbent that will require a reduced amount of steam. The process is based on advanced carbon sorbents having a low heat of adsorption, high CO2 adsorption capacity, and excellent selectivity. While the intent of this project was to produce design and performance data by testing the sorbent using a slipstream of coal-derived flue gas at the National Carbon Capture Center (NCCC) under realistic conditions and continuous long-term operation, the project was terminated following completion of the detailing pilot plant design/engineering work on June 30, 2016.

  4. Effect of sulfur dioxide partial pressure on the reaction of iodine, sulfur dioxide and water

    International Nuclear Information System (INIS)

    Nakajima, Hayato; Imai, Yoshiyuki; Kasahara, Seiji; Kubo, Shinji; Onuki, Kaoru

    2007-01-01

    Effect of sulfur dioxide partial pressure on the reaction of iodine, sulfur dioxide and water, which is a unit reaction in the IS process for thermochemical hydrogen production, was studied experimentally at 323 K under iodine saturation. Quasi-equilibrium state was observed in the presence of sulfur dioxide gas at constant pressure. The composition of the poly-hydriodic acid solution formed was discussed assuming an ideal desulfurization by the reverse reaction of the Bunsen reaction. The value of HI/(HI+H 2 O) of the desulfurized solution was large at high sulfur dioxide pressure and reached the maximum of 15.7 ± 0.3 mol%. (author)

  5. Carbon nanocomposite sorbent and methods of using the same for separation of one or more materials from a gas stream

    Science.gov (United States)

    Olson, Edwin S.; Pavlish, John Henry

    2017-05-30

    The present invention relates to carbon nanocomposite sorbents. The present invention provides carbon nanocomposite sorbents, methods for making the same, and methods for separation of a pollutant from a gas that includes that pollutant. Various embodiments provide a method for reducing the mercury content of a mercury-containing gas.

  6. Flow injection gas chromatography with sulfur chemiluminescence detection for the analysis of total sulfur in complex hydrocarbon matrixes.

    Science.gov (United States)

    Hua, Yujuan; Hawryluk, Myron; Gras, Ronda; Shearer, Randall; Luong, Jim

    2018-01-01

    A fast and reliable analytical technique for the determination of total sulfur levels in complex hydrocarbon matrices is introduced. The method employed flow injection technique using a gas chromatograph as a sample introduction device and a gas phase dual-plasma sulfur chemiluminescence detector for sulfur quantification. Using the technique described, total sulfur measurement in challenging hydrocarbon matrices can be achieved in less than 10 s with sample-to-sample time ideal for fast analysis or trace sulfur analysis. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. A primer on sulfur for the planetary geologist

    Science.gov (United States)

    Theilig, E.

    1982-01-01

    Sulfur has been proposed as the dominant composition for the volcanic material on Io. Sulfur is a complex element which forms many intramolecular and intermolecular allotropes exhibiting a variety of physical properties. Cyclo-S8 sulfur is the most abundant and stable molecular form. The important molecular species within liquid sulfur change in concentration with temperature. Concentrations of the allotropes control the physical properties of the melt. Discontinuities in density, viscosity, and thermal properties reflect the polymerization process within liquid sulfur. Variations in the melting point are related to autodissociation of the liquid. Many solids forms of sulfur have been identified but only orthorhombic alpha and monoclinic beta sulfur, both composed of cyclo-S8 sulfur, are stable under terrestrial conditions. Physical properties of solid sulfur are dependent on the allotrope and, in some cases, the thermal history. Three natural terrestrial sulfur flows are described: (1) Siretoko-Iosan, Japan; (2) Volcan Azufre, Galapagos Islands; and (3) Mauna Loa, Hawaii. All of the flows are associated with fumarolic areas and are considered to have formed by the melting and mobilization of sulfur deposits. Surface textures of the flows indicate a behavior of molten sulfur similar to that of silicate lava. Channels, rivulets, and lobate edges were described for the flows. The solidification of man-made sulfur flows formed as part of the Frasch mining process by which sulfur is removed from the subsurface in a liquid state is described.

  8. Mercury adsorption properties of sulfur-impregnated adsorbents

    Science.gov (United States)

    Hsi, N.-C.; Rood, M.J.; Rostam-Abadi, M.; Chen, S.; Chang, R.

    2002-01-01

    Carbonaceous and noncarbonaceous adsorbents were impregnated with elemental sulfur to evaluate the chemical and physical properties of the adsorbents and their equilibrium mercury adsorption capacities. Simulated coal combustion flue gas conditions were used to determine the equilibrium adsorption capacities for Hg0 and HgCl2 gases to better understand how to remove mercury from gas streams generated by coal-fired utility power plants. Sulfur was deposited onto the adsorbents by monolayer surface deposition or volume pore filling. Sulfur impregnation increased the total sulfur content and decreased the total and micropore surface areas and pore volumes for all of the adsorbents tested. Adsorbents with sufficient amounts of active adsorption sites and sufficient microporous structure had mercury adsorption capacities up to 4,509 ??g Hg/g adsorbent. Elemental sulfur, organic sulfur, and sulfate were formed on the adsorbents during sulfur impregnation. Correlations were established with R2>0.92 between the equilibrium Hg0/HgCl2 adsorption capacities and the mass concentrations of elemental and organic sulfur. This result indicates that elemental and organic sulfur are important active adsorption sites for Hg0 and HgCl2.

  9. Effects of rapid calcination on properties of calcium-based sorbents

    International Nuclear Information System (INIS)

    Yan, Chang-Feng; Grace, John R.; Lim, C. Jim

    2010-01-01

    The calcination process may influence subsequent fragmentation, sintering and swelling when CaO derived from limestone acts as a CO 2 or SO 2 -sorbent in combustion, gasification and reforming. Sorbent properties are affected by CO 2 partial pressure, total pressure, temperature, heating rate, impurities and sample size. In this study, the effect of calcination heating rate was investigated based on an electrically heated platinum foil. The effects of heating rate (up to 800 C/s), calcination temperature (700-950 C), particle size (90-180 μm) and sweep gas velocity were investigated. Higher initial heating rates led to lower extents of limestone calcination, but the extents of carbonation of the resulting CaO were similar to each other. Calcium utilization declined markedly during carbonation or sulphation of CaO after calcination by rapid heating. Experimental results show that carbonation and calcium utilization were most effective for carbonation temperatures between 503 and 607 C. Increasing the extent of calcination is not the best way to improve overall calcium utilization due to the vast increase in energy consumption. (author)

  10. The influence of reactivation by hydration of spent SO{sub 2} sorbents on their impact fragmentation in fluidized bed combustors

    Energy Technology Data Exchange (ETDEWEB)

    Montagnaro, F.; Salatino, P.; Santoro, L.; Scala, F. [University of Naples Federico II, Naples (Italy)

    2010-09-01

    The relationship between calcination/sulphation and attrition/fragmentation of calcium-based SO{sub 2} sorbents in fluidized bed (FB) combustors has long been recognized, but only recently did attrition by impact receive due consideration. There is limited available information in the literature on the propensity of exhausted calcium-based sorbents to undergo high-velocity impact fragmentation after they have been reactivated by steam or water hydration. The present study addresses the relationship between hydration-induced reactivation of spent Ca-based sorbents and attrition by impact loading. The sorbent used in this work (a high-calcium Italian limestone) was pre-processed (sulphation at 850{sup o}C in a lab-scale FB, water hydration for 3 h at 25{sup o}C in a thermostatic bath, steam hydration for 3 h at 250 degrees C in a tubular reactor, dehydration at 850{sup o}C in the FB) and subjected to impact tests in a purposely designed impact test rig, operated with particle impact velocities ranging from 4 to 45 m s{sup -1}. The particle size distribution of the debris was worked out to define a fragmentation index and a probability density function of the size of generated fragments. The effect of hydration/reactivation of spent sorbent on propensity to undergo impact fragmentation was assessed, and results are discussed in the light of a mechanistic framework. It was observed that the prevailing particle breakage pattern was splitting/chipping for water-reactivated samples, disintegration for steam-reactivated samples. Characterization of sorbent microstructure by porosimetry and microscopic investigation on the reactivated samples highlighted a clear relationship between the extent of fragmentation and the cumulative specific volume of mesopores.

  11. Factors affecting cleanup of exhaust gases from a pressurized, fluidized-bed coal combustor

    Science.gov (United States)

    Rollbuhler, R. J.; Kobak, J. A.

    1980-01-01

    The cleanup of effluent gases from the fluidized-bed combustion of coal is examined. Testing conditions include the type and feed rate of the coal and the sulfur sorbent, the coal-sorbent ratio, the coal-combustion air ratio, the depth of the reactor fluidizing bed, and the technique used to physically remove fly ash from the reactor effluent gases. Tests reveal that the particulate loading matter in the effluent gases is a function not only of the reactor-bed surface gas velocity, but also of the type of coal being burnt and the time the bed is operating. At least 95 percent of the fly ash particules in the effluent gas are removed by using a gas-solids separator under controlled operating conditions. Gaseous pollutants in the effluent (nitrogen and sulfur oxides) are held within the proposed Federal limits by controlling the reactor operating conditions and the type and quantity of sorbent material.

  12. Comparative analysis of the mechanisms of sulfur anion oxidation and reduction by dsr operon to maintain environmental sulfur balance.

    Science.gov (United States)

    Ghosh, Semanti; Bagchi, Angshuman

    2015-12-01

    Sulfur metabolism is one of the oldest known redox geochemical cycles in our atmosphere. These redox processes utilize different sulfur anions and the reactions are performed by the gene products of dsr operon from phylogenetically diverse sets of microorganisms. The operon is involved in the maintenance of environmental sulfur balance. Interestingly, the dsr operon is found to be present in both sulfur anion oxidizing and reducing microorganisms and in both types of organisms DsrAB protein complex plays a vital role. Though there are various reports regarding the genetics of dsr operon there are practically no reports dealing with the structural aspects of sulfur metabolism by dsr operon. In our present study, we tried to compare the mechanisms of sulfur anion oxidation and reduction by Allochromatium vinosum and Desulfovibrio vulgaris respectively through DsrAB protein complex. We analyzed the modes of bindings of sulfur anions to the DsrAB protein complex and observed that for sulfur anion oxidizers, sulfide and thiosulfate are the best substrates whereas for reducers sulfate and sulfite have the best binding abilities. We analyzed the binding interaction pattern of the DsrA and DsrB proteins while forming the DsrAB protein complexes in Desulfovibrio vulgaris and Allochromatium vinosum. To our knowledge this is the first report that analyzes the differences in binding patterns of sulfur substrates with DsrAB protein from these two microorganisms. This study would therefore be essential to predict the biochemical mechanism of sulfur anion oxidation and reduction by these two microorganisms i.e., Desulfovibrio vulgaris (sulfur anion reducer) and Allochromatium vinosum (sulfur anion oxidizer). Our observations also highlight the mechanism of sulfur geochemical cycle which has important implications in future study of sulfur metabolism as it has a huge application in waste remediation and production of industrial bio-products viz. vitamins, bio-polyesters and bio

  13. In vitro catheter and sorbent-based method for clearance of radiocontrast material during cerebral interventions

    International Nuclear Information System (INIS)

    Angheloiu, George O.; Hänscheid, Heribert; Reiners, Christoph; Anderson, William D.; Kellum, John A.

    2013-01-01

    Background: Contrast-induced acute kidney injury is a severe condition resulting from the use of radiology contrast in patients with predisposing factors. Hypothesis: We hypothesized that a novel system including a device containing polymer resin sorbent beads and a custom-made suctioning catheter could efficiently remove contrast from an in vitro novel model of circulatory system (MOCS) mimicking the cerebral circulation. Methods: A custom-made catheter was built and optimized for cerebral venous approach. The efficiency of a system made of a polymer resin sorbent beads column (CST 401, Cytosorbents) and this particular catheter was tested in the MOCS running a solution composed of 0.9% saline and radio-contrast. During two series of 18 cycles of first-pass experiments we assessed the catheter's suctioning efficiency and the system's ability to clear radio-contrast injected into the MOCS's cerebral arterial segment. We also assessed the functioning and reliability of the MOCS. Results: Mean suctioning efficiency of the catheter was 84% ± 24%. The polymer sorbent column contrast removal rate was initially 96% and gradually decreased with subsequent cycles in a linear fashion during an experiment lasting approximately 90 minutes. The MOCS had a reliability of 0.9946×min −1 where 1 × min −1 was the optimum value. Conclusion: A system including a polymer resin sorbent beads column and a custom-made suctioning catheter had an excellent initial efficiency in quickly removing contrast from an artificial MOCS mimicking the cerebral circulation. MOCS is an inexpensive and relatively reliable custom-made system that can be used for training or testing purposes

  14. Imprint-coating synthesis of selective functionalized ordered mesoporous sorbents for separation and sensors

    Science.gov (United States)

    Dai, Sheng; Burleigh, Mark C.; Shin, Yongsoon

    2001-01-01

    The present invention relates generally to mesoporous sorbent materials having high capacity, high selectivity, fast kinetics, and molecular recognition capability. The invention also relates to a process for preparing these mesoporous substrates through molecular imprinting techniques which differ from convention techniques in that a template molecule is bound to one end of bifunctional ligands to form a complex prior to binding of the bifunctional ligands to the substrate. The present invention also relates to methods of using the mesoporous sorbent materials, for example, in the separation of toxic metals from process effluents, paints, and other samples; detection of target molecules, such as amino acids, drugs, herbicides, fertilizers, and TNT, in samples; separation and/or detection of substances using chromatography; imaging agents; sensors; coatings; and composites.

  15. Electrostatic interactions between immunoglobulin (IgG) molecules and a charged sorbent

    NARCIS (Netherlands)

    Bremer, M.G.E.G.; Duval, J.; Norde, Willem; Lyklema, J.

    2004-01-01

    The influence of electrostatic interactions on the adsorption of IgG is examined both theoretically and experimentally. The long-range interaction between IgG and the charged sorbent surface is treated in terms of the DLVO theory taking into account the possibility of charge- and potential

  16. Evaluation of Sorbents for Acetylene Separation in Atmosphere Revitalization Loop Closure

    Science.gov (United States)

    Abney, Morgan B.; Miller, Lee A.; Barton, Katherine

    2012-01-01

    State-of-the-art carbon dioxide reduction technology uses a Sabatier reactor to recover water from metabolic carbon dioxide. In order to maximize oxygen loop closure, a byproduct of the system, methane, must be reduced to recover hydrogen. NASA is currently exploring a microwave plasma methane pyrolysis system for this purpose. The resulting product stream of this technology includes unreacted methane, product hydrogen, and acetylene. The hydrogen and the small amount of unreacted methane resulting from the pyrolysis process can be returned to the Sabatier reactor thereby substantially improving the overall efficiency of the system. However, the acetylene is a waste product that must be removed from the pyrolysis product. Two materials have been identified as potential sorbents for acetylene removal: zeolite 4A, a commonly available commercial sorbent, and HKUST-1, a newly developed microporous metal. This paper provides an explanation of the rationale behind acetylene removal and the results of separation testing with both materials

  17. A comparative study of homemade C18 and commercial C18 sorbents for preconcentration of lead by minicolumn solid phase extraction

    International Nuclear Information System (INIS)

    Maltez, H.F.; Curtius, A.J.; Carasek, E.; Melo, L.F.C.; Sales Fontes Jardim, I.C.; Nascimento de Queiroz do, S.C.

    2004-01-01

    A comparative study of commercial C 18 chemically immobilized on silica and homemade C 18 , as sorbents for Pb complexed with 0,0-diethyl-dithiophosphate (DDTP) in a flow injection preconcentration system is reported. The homemade C 18 sorbent was obtained by sorption of poly(methyloctadecylsiloxane) (PMODS) on the silica support followed by immobilization using thermal treatment. The method follows the concept of green chemistry, since there are no toxic residues after synthesis. The complexed Pb was formed in 1.0 mol L -1 HCI medium and retained on the minicolumn filled with the sorbents. The elution was carried out using ethanol, and the richest 210 μL fraction was collected and analyzed by flame atomic absorption spectrometry. Chemical and flow variables were optimized for each sorbent. The results demonstrated that the performance of the proposed homemade C 18 sorbent for preconcentration of Pb complexed with DDTP is very similar to commercial C 18 chemically bonded on silica. By processing 25 mL, the enrichment factors were 129 and 125 for commercial C 18 and homemade C 18 , respectively. The limit of detection for commercial and homemade C 18 was 0.2 μg L -1 and 0.6 μg L -1 , respectively. The relative standard deviation (RSD) was lower than 1.2 % for both sorbents for a Pb concentration of 100 μg L -1 . The method was also applied successfully to the analysis of water samples, and the accuracy was tested by recovery measurements on spiked samples and biological reference material. (author)

  18. 46 CFR 151.50-21 - Sulfuric acid.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Sulfuric acid. 151.50-21 Section 151.50-21 Shipping... BULK LIQUID HAZARDOUS MATERIAL CARGOES Special Requirements § 151.50-21 Sulfuric acid. (a) How sulfuric acid may be carried. (1) Sulfuric acid of concentration of 77.5 percent (1.7019 specific gravity) (59.8...

  19. 46 CFR 153.1046 - Sulfuric acid.

    Science.gov (United States)

    2010-10-01

    ... 46 Shipping 5 2010-10-01 2010-10-01 false Sulfuric acid. 153.1046 Section 153.1046 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) CERTAIN BULK DANGEROUS CARGOES SHIPS CARRYING BULK....1046 Sulfuric acid. No person may liquefy frozen or congealed sulfuric acid other than by external tank...

  20. Evaluation of LTA-, FAU- and MFI-type zeolites as sorbents of some toxic components of tobacco smoke

    International Nuclear Information System (INIS)

    Iucolano, F.; Caputo, D.; Monetta, T.; Bellucci, F.; Colella, C.

    2008-01-01

    Zeolites 3A, 4A, 13X, H-ZSM-5 were investigated in order to evaluate their possible use in removing toxic compounds from cigarette smoke. Ammonia and acetaldehyde were selected as representative of a wide range of possible sorbates. Adsorption equilibrium data at 313K were collected and analyzed by Langmuir and virial equations to estimate the relevant values of Henry's constant, a useful parameter to estimate the affinity sorbents-sorbates at low pressure. Unlike the Langmuir model, the virial equation provided a good fit for both ammonia and acetaldehyde equilibrium data for all sorbents in the whole range of pressures, especially at low pressure. As already assessed for nitrosamines, FAU- and MFI-type zeolites showed the highest affinity for ammonia and acetaldehyde, allowing these sorbents to be considered an effective potential resource for the removal of some of the main pollutants of tobacco smoke.

  1. Influence of coal properties on mercury uptake from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Lakatos, J.; Brown, S.D.; Snape, C.E. [Miskolc University, Miskolc-Egyetemvaros (Hungary). Research Inst. of Applied Chemistry

    1999-10-01

    The uptake of mercury (II) from aqueous solution by a range of coals has been studied and the results have been compared to those for a number of other sorbents, including commercial active carbons and cation-exchange resins. At pH 5 in a buffer medium, the capacities for mercury removal of the low-rank coals and the oxidized bituminous coals investigated are comparable to those of the other sorbents tested. For the lignites investigated, a high content of organic sulfur does not markedly affect the capacity for mercury uptake in relatively neutral and low chloride media, owing to redox reactions being the most likely mechanism involved. However, in highly acidic solutions, the capacities for mercury uptake are considerably greater for the high-sulfur coals investigated than for their low-sulfur counterparts due to chelation being the major sorption process involved. 36 refs., 4 figs., 7 tabs.

  2. Characteristic of New Solid-Phase Extraction Sorbent: Activated Carbon Prepared from Rice Husks under Base Treated Condition

    Directory of Open Access Journals (Sweden)

    Afrida Kurnia Putri

    2012-10-01

    Full Text Available A characterization of activated carbon (ACs prepared from rice husks (RHs under base treated condition as a new sorbent for solid-phase extraction (SPE to extract 4-nonylphenol isomers (4-NPs in water samples has been done. The ACs prepared from RHs usually exhibits low specific surface area due to its high ash content, but in case of its application for SPE, there are other factors need to be considered, such as the existence of functional groups inside the sorbent, that can enhance interaction of non-polar sorbent with analyte in the water matrices. In this case, silanol groups from ash content may affect the extraction efficiency for 4-NPs. The ACs made from RHs were chemically impregnated with ZnCl2 and carbonized at 800oC. To investigate the role of silica, three types of ACs were prepared, i.e., untreated ACs (AC–Si, contain silica, base treated ACs (AC–B–Si, remain some silica inside, and ACs made by base treated RHs (AC–B, no silica, the surface area obtained from these treatments were 1352 m2/g, 1666 m2/g, and 1712m2/g respectively.  ACs made by base treatment has the highest surface area (related to BET, which indicat that silica removal process promotes the formation of open pore system on ACs and enhances the surface area of ACs. However, extraction efficiency measured by GC-MS in SPE process showed the reversal trends (i.e., AC–Si= 32.08%, AC–B–Si= 82.63%, AC–B=51.78%, among them the AC–B–Si sorbent reveal the best performance in SPE process. It is indicated that although silica usually exhibits low specific surface area, but control presence of silica as a polar functional group has a positive influence in the interaction between non-polar sorbent and 4-NPs.

  3. Sensing sulfur oxides and other sulfur bearing pollutants with solid electrolyte pellets. I. Gas concentration cells

    Energy Technology Data Exchange (ETDEWEB)

    Chamberland, A M; Gauthier, J M

    1977-01-01

    A new sensing technique using a solid electrolyte has been demonstrated for sulfur-bearing pollutants. Based on potentiometric measurements across a pellet of potassium sulfate, this sensor allows concentrations of sulfur dioxides, sulfur trioxide, hydrogen sulfide, methyl mercaptan and carbonyl sulfide in air to be measured with accuracy. Its operational concentration range at the present time is 0.1 ppM up to at least 10,000 ppM. The presence of other common pollutants such as carbon dioxide, methane, nitric oxide and nitrogen dioxide does not interfere with the measurement of air samples containing sulfur-bearing pollutants.

  4. Feasibility Study for the Use of Green, Bio-Based, Efficient Reactive Sorbent Material to Neutralize Chemical Warfare Agents

    Science.gov (United States)

    2012-08-02

    REPORT Feasibility study for the use of green, bio-based, efficient reactive sorbent material to neutralize chemical warfare agents 14. ABSTRACT 16...way cellulose, lignin and hemicelluloses interact as well as whole wood dissolution occurs in ILs. The present project was conducted to 1. REPORT...Feasibility study for the use of green, bio-based, efficient reactive sorbent material to neutralize chemical warfare agents Report Title ABSTRACT Over the

  5. A highly efficient and selective polysilsesquioxane sorbent for heavy metal removal

    KAUST Repository

    Duan, Xiaonan; Qi, Genggeng; Wang, Peng; Giannelis, Emmanuel P.

    2012-01-01

    Suited for heavy stuff: An efficient mesoporous sorbent based on a pure ethylendiamine-bridged polysilsesquioxane is presented. This material, with both a high amine loading and a high surface area, is applied for heavy metal ion removal. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  6. A highly efficient and selective polysilsesquioxane sorbent for heavy metal removal

    KAUST Repository

    Duan, Xiaonan

    2012-02-29

    Suited for heavy stuff: An efficient mesoporous sorbent based on a pure ethylendiamine-bridged polysilsesquioxane is presented. This material, with both a high amine loading and a high surface area, is applied for heavy metal ion removal. Copyright © 2012 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. 21 CFR 582.1095 - Sulfuric acid.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Sulfuric acid. 582.1095 Section 582.1095 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1095 Sulfuric acid. (a) Product. Sulfuric acid. (b) Conditions of use. This substance is generally...

  8. Preliminary carbon dioxide capture technical and economic feasibility study evaluation of carbon dioxide capture from existing fired plants by hybrid sorption using solid sorbents

    Energy Technology Data Exchange (ETDEWEB)

    Benson, Steven; Envergex, Srivats; Browers, Bruce; Thumbi, Charles

    2013-01-01

    Barr Engineering Co. was retained by the Institute for Energy Studies (IES) at University of North Dakota (UND) to conduct a technical and economic feasibility analysis of an innovative hybrid sorbent technology (CACHYS™) for carbon dioxide (CO2) capture and separation from coal combustion–derived flue gas. The project team for this effort consists of the University of North Dakota, Envergex LLC, Barr Engineering Co., and Solex Thermal Science, along with industrial support from Allete, BNI Coal, SaskPower, and the North Dakota Lignite Energy Council. An initial economic and feasibility study of the CACHYS™ concept, including definition of the process, development of process flow diagrams (PFDs), material and energy balances, equipment selection, sizing and costing, and estimation of overall capital and operating costs, is performed by Barr with information provided by UND and Envergex. The technology—Capture from Existing Coal-Fired Plants by Hybrid Sorption Using Solid Sorbents Capture (CACHYS™)—is a novel solid sorbent technology based on the following ideas: reduction of energy for sorbent regeneration, utilization of novel process chemistry, contactor conditions that minimize sorbent-CO2 heat of reaction and promote fast CO2 capture, and a low-cost method of heat management. The technology’s other key component is the use of a low-cost sorbent.

  9. Improvement of CaO-based sorbent performance for CO{sub 2} looping cycles

    Energy Technology Data Exchange (ETDEWEB)

    Vasilije Manovic; Edward J. Anthony [CANMET Energy Technology Centre-Ottawa, Ottawa, ON (Canada)

    2009-07-01

    This paper presents research on CO{sub 2} capture by lime-based looping cycles. This is a new and promising technology that may help in mitigation of global warming and climate change caused primarily by the use of fossil fuels. The intensity of the anticipated changes urgently requires solutions such as the developing technologies for CO{sub 2} capture, especially those based on CaO looping cycles. This technology is at the pilot plant demonstration stage and there are still significant challenges that require solutions. The technology is based on a dual fluidized bed reactor which contains a carbonator - a unit for CO{sub 2} capture, and a calciner - a unit for CaO regeneration. The major technology components are well known from other technologies and easily applicable. However, even though CaO is a very good candidate as a solid CO{sub 2} carrier, its performance in a practical system still has significant limitations. Thus, research on CaO performance is critical and this paper discusses some of the more important problems and potential solutions that are being examined at CETC-O. To date, the most promising methods were reactivation of spent sorbent by steam, thermal pretreatment of sorbent, and doping, most likely with Al{sub 2}O{sub 3}. The combination of these methods, including pelletization, should provide us with enhanced sorbent performance. 75 refs., 19 figs.

  10. Application of Chemically Modified and Unmodified Waste Biological Sorbents in Treatment of Wastewater

    Directory of Open Access Journals (Sweden)

    John Kanayochukwu Nduka

    2012-01-01

    Full Text Available Protein wastes (feathers, goat hair and cellulosic wastes (corn cob, coconut husks were collected and washed with detergent solution, thoroughly rinsed and sun dried for 2 days before drying in an oven, and then ground. One-half of ground material was carbonized at a maximum temperature of 500°C after mixing with H2SO4. The carbonized parts were pulverized; both carbonized and uncarbonized sorbents were sieved into two particle sizes of 325 and 625 μm using mechanical sieve. Sorbents of a given particle size were packed into glass column.Then, textile wastewater that had its physicochemical parameters previously determined was eluted into each glass column and a contact time of 60 and 120 mins was allowed before analysis. Results showed 48.15–99.98 percentage reduction of NO3−, EC, Cl−, BOD, COD, DO, TSS, and TDS, 34.67–99.93 percentage reduction of NO3−, EC, Cl−, BOD, COD, DO, TSS, and TDS, 52.83–97.95 percentage reduction of Pb2+, Ni2+, Cr3+ and Mn2+ and 34.59–94.87 percentage reduction of Pb2+, Ni2+, Cr3+ and Mn2+. Carbonization, small particle, size and longer contact time enhanced the sorption capabilities of the sorbents. These show that protein and cellulosic wastes can be used to detoxify wastewater.

  11. Io's theothermal (sulfur) - Lithosphere cycle inferred from sulfur solubility modeling of Pele's magma supply

    Science.gov (United States)

    Battaglia, Steven M.; Stewart, Michael A.; Kieffer, Susan W.

    2014-06-01

    Surface deposits of volatile compounds such as water (Earth) or sulfur (Io) on volcanically active bodies suggest that a magmatic distillation process works to concentrate volatiles in surface reservoirs. On Earth, this is the combined hydrologic and tectonic cycle. On Io, sulfurous compounds are transferred from the interior to the surface reservoirs through a combination of a mantle-sourced magmatic system, vertical cycling of the lithosphere, and a sulfur-dominated crustal thermal system that we here call the "theothermal" system. We present a geochemical analysis of this process using previously inferred temperature and oxygen fugacity constraints of Pele's basaltic magma to determine the behavior of sulfur in the ionian magmas. Sulfate to sulfide ratios of Pele's magma are -4.084 ± 0.6 and -6.442 ± 0.7 log10 units, comparable to or lower than those of mid-ocean ridge basalts. This reflects the similarity of Io's oxidation state with Earth's depleted mantle as previously suggested by Zolotov and Fegley (Zolotov, M.Y., Fegley, B. [2000]. Geophys. Res. Lett. 27, 2789-2792). Our calculated limits of sulfur solubility in melts from Pele's patera (˜1100-1140 ppm) are also comparable to terrestrial mid-ocean ridge basalts, reflecting a compositional similarity of mantle sources. We propose that the excess sulfur obvious on Io's surface comes from two sources: (1) an insoluble sulfide liquid phase in the magma and (2) theothermal near-surface recycling.

  12. Quantification of Discrete Oxide and Sulfur Layers on Sulfur-Passivated InAs by XPS

    National Research Council Canada - National Science Library

    Petrovykh, D. Y; Sullivan, J. M; Whitman, L. J

    2005-01-01

    .... The S-passivated InAs(001) surface can be modeled as a sulfur-indium-arsenic layer-cake structure, such that characterization requires quantification of both arsenic oxide and sulfur layers that are at most a few monolayers thick...

  13. Sulfur and Oxygen Isotope Fractionation During Bacterial Sulfur Disproportionation Under Anaerobic Haloalkaline Conditions

    NARCIS (Netherlands)

    Poser, Alexander; Vogt, Carsten; Knöller, Kay; Sorokin, Dimitry Y.; Finster, Kai W.; Richnow, Hans H.

    2016-01-01

    Sulfur and oxygen isotope fractionation of elemental sulfur disproportionation at anaerobic haloalkaline conditions was evaluated for the first time. Isotope enrichment factors of the strains Desulfurivibrio alkaliphilus and Dethiobacter alkaliphilus growing at pH 9 or 10 were −0.9‰ to −1‰ for

  14. Air Quality Criteria for Sulfur Oxides.

    Science.gov (United States)

    National Air Pollution Control Administration (DHEW), Washington, DC.

    Included is a literature review which comprehensively discusses knowledge of the sulfur oxides commonly found in the atmosphere. The subject content is represented by the 10 chapter titles: Physical and Chemical Properties and the Atmospheric Reactions of the Oxides of Sulfur; Sources and Methods of Measurements of Sulfur Oxides in the Atmosphere;…

  15. Ruthenium complexing in sorption by granulated sorbents with ethylene diamine and diethyl amine groups

    International Nuclear Information System (INIS)

    Simanova, S.A.; Kolmakova, A.I.; Konovalov, L.V.; Kukushkin, Yu.N.; Kalalova, E.

    1986-01-01

    The sorption process of ruthenium (4) chlorocomplexes - K 2 (RuCl 6 ) macroporous granulated copolymers of glycidylmethacrylate ethylene dimethacrylate with ethylene diamine and diethyl amine has been studied. Sorption has been carried out under the static conditions (at 20 and 98 deg C) from 0.1-2.0 MxHCl and 1.0 M NaCl solutions. It is established that the sorption from acidic solutions proceeds according to anion exchange mechanism with formation of onium chlorocomplexes in the sorbent phase, subjecting to Anderson regrouping during the heating. During the sorption from neutral solutions the second-sphere coordination of polymer amino groups accirs near ruthenium atom and amino-chloride complexes are formed in the sorbent phase

  16. Model Prebiotic Iron-Sulfur Peptides

    Science.gov (United States)

    Bonfio, C.; Scintilla, S.; Shah, S.; Evans, D. J.; Jin, L.; Szostak, J. W.; Sasselov, D. D.; Sutherland, J. D.; Mansy, S. S.

    2017-07-01

    Iron-sulfur clusters form easily in aqueous solution in the presence of thiolates and iron ions. Polymerization of short, iron-sulfur binding tripeptide sequences leads to ferredoxin-like ligand spacing and activity.

  17. The ADESORB Process for Economical Production of Sorbents for Mercury Removal from Coal Fired Power Plants

    Energy Technology Data Exchange (ETDEWEB)

    Robin Stewart

    2008-03-12

    The DOE's National Energy Technology Laboratory (NETL) currently manages the largest research program in the country for controlling coal-based mercury emissions. NETL has shown through various field test programs that the determination of cost-effective mercury control strategies is complex and highly coal- and plant-specific. However, one particular technology has the potential for widespread application: the injection of activated carbon upstream of either an electrostatic precipitator (ESP) or a fabric filter baghouse. This technology has potential application to the control of mercury emissions on all coal-fired power plants, even those with wet and dry scrubbers. This is a low capital cost technology in which the largest cost element is the cost of sorbents. Therefore, the obvious solutions for reducing the costs of mercury control must focus on either reducing the amount of sorbent needed or decreasing the cost of sorbent production. NETL has researched the economics and performance of novel sorbents and determined that there are alternatives to the commercial standard (NORIT DARCO{reg_sign} Hg) and that this is an area where significant technical improvements can still be made. In addition, a key barrier to the application of sorbent injection technology to the power industry is the availability of activated carbon production. Currently, about 450 million pounds ($250 million per year) of activated carbon is produced and used in the U.S. each year - primarily for purification of drinking water, food, and beverages. If activated carbon technology were to be applied to all 1,100 power plants, EPA and DOE estimate that it would require an additional $1-$2 billion per year, which would require increasing current capacity by a factor of two to eight. A new facility to produce activated carbon would cost approximately $250 million, would increase current U.S. production by nearly 25%, and could take four to five years to build. This means that there could be

  18. Research of a possibility of receiving sorbents for a sewage disposal from a wastage of coal preparation factory

    International Nuclear Information System (INIS)

    Buyantuev, S L; Stebenkova, Y Y; Khmelev, A B; Kondratenko, A S; Shishulkin, S Y

    2017-01-01

    The paper presents the results of the studies of the structure and porosity of the coal cake processed by electric arc plasma. The main limiting factor in processing of coal cakes sorbents is their high water content. As a result of coal washing, the main share of water introduced into the cake falls on hard-hydrate and colloidal components. This makes impossible application of traditional processes of manufacturing from a cake of coal sorbents. Using the electric arc intensifies the processes of thermal activation of coal cakes associated with thermal shock, destruction and vapor-gas reactions occurring at the surfaces of the particles at an exposure temperature of up to 3000 °C, which increases the title product outlet (sorbent) and thereby reduces manufacturing costs and improves environmental performance. The investigation of the thermal activation zone is carried out in the plasma reactor chamber by thermal imaging method followed by mapping-and 3D-modeling of temperature fields. the most important physical and chemical properties of the sorbents from coal cake activated by plasma was studied. The obtained results showed the possibility of coal cake thermal activation by electric arc plasma to change its material composition, the appearance of porosity and associated sorption capacity applied for wastewater treatment. (paper)

  19. Research of a possibility of receiving sorbents for a sewage disposal from a wastage of coal preparation factory

    Science.gov (United States)

    Buyantuev, S. L.; Kondratenko, A. S.; Shishulkin, S. Y.; Stebenkova, Y. Y.; Khmelev, A. B.

    2017-05-01

    The paper presents the results of the studies of the structure and porosity of the coal cake processed by electric arc plasma. The main limiting factor in processing of coal cakes sorbents is their high water content. As a result of coal washing, the main share of water introduced into the cake falls on hard-hydrate and colloidal components. This makes impossible application of traditional processes of manufacturing from a cake of coal sorbents. Using the electric arc intensifies the processes of thermal activation of coal cakes associated with thermal shock, destruction and vapor-gas reactions occurring at the surfaces of the particles at an exposure temperature of up to 3000 °C, which increases the title product outlet (sorbent) and thereby reduces manufacturing costs and improves environmental performance. The investigation of the thermal activation zone is carried out in the plasma reactor chamber by thermal imaging method followed by mapping-and 3D-modeling of temperature fields. the most important physical and chemical properties of the sorbents from coal cake activated by plasma was studied. The obtained results showed the possibility of coal cake thermal activation by electric arc plasma to change its material composition, the appearance of porosity and associated sorption capacity applied for wastewater treatment.

  20. Cell Concepts of Metal-Sulfur Batteries (Metal = Li, Na, K, Mg): Strategies for Using Sulfur in Energy Storage Applications.

    Science.gov (United States)

    Medenbach, Lukas; Adelhelm, Philipp

    2017-09-29

    There is great interest in using sulfur as active component in rechargeable batteries thanks to its low cost and high specific charge (1672 mAh/g). The electrochemistry of sulfur, however, is complex and cell concepts are required, which differ from conventional designs. This review summarizes different strategies for utilizing sulfur in rechargeable batteries among membrane concepts, polysulfide concepts, all-solid-state concepts as well as high-temperature systems. Among the more popular lithium-sulfur and sodium-sulfur batteries, we also comment on recent results on potassium-sulfur and magnesium-sulfur batteries. Moreover, specific properties related to the type of light metal are discussed.