Carbon dioxide sensor

Science.gov (United States)

Dutta, Prabir K [Worthington, OH; Lee, Inhee [Columbus, OH; Akbar, Sheikh A [Hilliard, OH

2011-11-15

The present invention generally relates to carbon dioxide (CO.sub.2) sensors. In one embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor that incorporates lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3). In another embodiment, the present invention relates to a carbon dioxide (CO.sub.2) sensor has a reduced sensitivity to humidity due to a sensing electrode with a layered structure of lithium carbonate and barium carbonate. In still another embodiment, the present invention relates to a method of producing carbon dioxide (CO.sub.2) sensors having lithium phosphate (Li.sub.3PO.sub.4) as an electrolyte and sensing electrode comprising a combination of lithium carbonate (Li.sub.2CO.sub.3) and barium carbonate (BaCO.sub.3).

Carbon Dioxide Mitigation Benefit of High-Speed Railway in Terms of Carbon Tax

Directory of Open Access Journals (Sweden)

Fu Yanbing

2013-01-01

Full Text Available This paper calculates the carbon dioxide mitigation benefit of high-speed railway based on the carbon dioxide tax policy. We define the carbon dioxide emission system boundary for high-speed railway in its whole life cycle and estimate the life cycle carbon dioxide inventories during its construction, application, and recovery stages. And then we establish a theoretical model to calculate the life cycle carbon dioxide mitigation quantity for high-speed railway when compared with road transport and then calculate its carbon dioxide mitigation benefit. The numerical example shows that the carbon dioxide mitigation benefit of high-speed railway is better than that of road transport from the whole life cycle perspective.

Carbon Dioxide Removal via Passive Thermal Approaches

Science.gov (United States)

Lawson, Michael; Hanford, Anthony; Conger, Bruce; Anderson, Molly

2011-01-01

A paper describes a regenerable approach to separate carbon dioxide from other cabin gases by means of cooling until the carbon dioxide forms carbon dioxide ice on the walls of the physical device. Currently, NASA space vehicles remove carbon dioxide by reaction with lithium hydroxide (LiOH) or by adsorption to an amine, a zeolite, or other sorbent. Use of lithium hydroxide, though reliable and well-understood, requires significant mass for all but the shortest missions in the form of lithium hydroxide pellets, because the reaction of carbon dioxide with lithium hydroxide is essentially irreversible. This approach is regenerable, uses less power than other historical approaches, and it is almost entirely passive, so it is more economical to operate and potentially maintenance- free for long-duration missions. In carbon dioxide removal mode, this approach passes a bone-dry stream of crew cabin atmospheric gas through a metal channel in thermal contact with a radiator. The radiator is pointed to reject thermal loads only to space. Within the channel, the working stream is cooled to the sublimation temperature of carbon dioxide at the prevailing cabin pressure, leading to formation of carbon dioxide ice on the channel walls. After a prescribed time or accumulation of carbon dioxide ice, for regeneration of the device, the channel is closed off from the crew cabin and the carbon dioxide ice is sublimed and either vented to the environment or accumulated for recovery of oxygen in a fully regenerative life support system.

Carbon Dioxide Detection and Indoor Air Quality Control.

Science.gov (United States)

Bonino, Steve

2016-04-01

When building ventilation is reduced, energy is saved because it is not necessary to heat or cool as much outside air. Reduced ventilation can result in higher levels of carbon dioxide, which may cause building occupants to experience symptoms. Heating or cooling for ventilation air can be enhanced by a DCV system, which can save energy while providing a comfortable environment. Carbon dioxide concentrations within a building are often used to indicate whether adequate fresh air is being supplied to the building. These DCV systems use carbon dioxide sensors in each space or in the return air and adjust the ventilation based on carbon dioxide concentration; the higher the concentration, the more people occupy the space relative to the ventilation rate. With a carbon dioxide sensor DCV system, the fresh air ventilation rate varies based on the number ofpeople in the space, saving energy while maintaining a safe and comfortable environment.

Phase equilibrium of binary system carbon dioxide - methanol at high pressure using artificial neural network

International Nuclear Information System (INIS)

Nasri, F.; Hatami, T.

2012-01-01

Interest in supercritical fluids extraction (SFE ) is increasing throughout many scientific and industrial fields. The common solvent for use in SFE is carbon dioxide. However, pure carbon dioxide frequently fails to efficiently extract the essential oil from a sample matrix, and modifier fluids such as methanol should be used to enhance extraction yield. A more efficient use of SFE requires quantitative prediction of phase equilibrium of this binary system, carbon dioxide - methanol. The purpose of the current research is modeling carbon dioxide - methanol system using artificial neural network (ANN). Results of ANN modeling has been compared with experimental data as well as thermodynamic equations of state. The comparison shows that the ANN modeling has a higher accuracy than thermodynamic models. (author)

Carbon dioxide as chemical feedstock

National Research Council Canada - National Science Library

Aresta, M

2010-01-01

... Dioxide as an Inert Solvent for Chemical Syntheses 15 Alessandro Galia and Giuseppe Filardo Introduction 15 Dense Carbon Dioxide as Solvent Medium for Chemical Processes 15 Enzymatic Catalysis in Dense Carbon Dioxide 18 Other Reactions in Dense Carbon Dioxide 19 Polymer Synthesis in Supercritical Carbon Dioxide 20 Chain Polymerizations: Synt...

46 CFR 169.565 - Fixed carbon dioxide system.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Fixed carbon dioxide system. 169.565 Section 169.565 Shipping COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED) NAUTICAL SCHOOLS SAILING SCHOOL VESSELS... cylinder storage area must be properly ventilated and the temperature inside must not exceed 130 °F. (g...

Absorption of carbon dioxide and isotope exchange rate of carbon in a reaction system between carbon dioxide and carbamic acid

International Nuclear Information System (INIS)

Takeshita, Kenji; Kitamoto, Asashi

1985-01-01

The performance of isotope separation of carbon-13 by chemical exchange between carbon dioxide and carbamic acid was studied. The working fluid used in the study was a solution of DNBA, (C 4 H 9 ) 2 NH and n-octane mixture. Factors related to the isotope exchange rate were measured, such as the absorption rate of carbon dioxide into the solution of DNBA and n-octane, the isotope exchange rate and the separation factor in the reaction between CO 2 and carbamic acid. The absorption of CO 2 into the working fluid was the sum of chemical absorption by DNBA and physical absorption by n-octane. The absorption of carbon dioxide into the working fluid was negligible at temperatures over 90 0 C, but increased gradually at lower temperatures. Carbon dioxide was absorbed into DNBA by chemical absorption, and DNBA was converted to carbamic acid by the reaction. The reaction for synthesis and decomposition of carbamic acid was reversible. The separation factor in equilibrium reached a large value at lower temperatures. The isotope exchange rate between gas and liquid was proportional to the product of the concentration of carbamic acid and the concentration of CO 2 by physical absorption. The isotope separation of carbon by chemical exchange reaction is better operated under the conditions of lower temperature and higher pressure. (author)

76 FR 55846 - Hazardous Waste Management System: Identification and Listing of Hazardous Waste: Carbon Dioxide...

Science.gov (United States)

2011-09-09

... carbon dioxide (CO 2 ) streams that are hazardous from the definition of hazardous waste, provided these... management under the Resource Conservation and Recovery Act (RCRA) to conditionally exclude carbon dioxide... 2050-AG60 Hazardous Waste Management System: Identification and Listing of Hazardous Waste: Carbon...

Carbon Dioxide Absorption Heat Pump

Science.gov (United States)

Jones, Jack A. (Inventor)

2002-01-01

A carbon dioxide absorption heat pump cycle is disclosed using a high pressure stage and a super-critical cooling stage to provide a non-toxic system. Using carbon dioxide gas as the working fluid in the system, the present invention desorbs the CO2 from an absorbent and cools the gas in the super-critical state to deliver heat thereby. The cooled CO2 gas is then expanded thereby providing cooling and is returned to an absorber for further cycling. Strategic use of heat exchangers can increase the efficiency and performance of the system.

Predator-induced reduction of freshwater carbon dioxide emissions

Science.gov (United States)

Atwood, Trisha B.; Hammill, Edd; Greig, Hamish S.; Kratina, Pavel; Shurin, Jonathan B.; Srivastava, Diane S.; Richardson, John S.

2013-03-01

Predators can influence the exchange of carbon dioxide between ecosystems and the atmosphere by altering ecosystem processes such as decomposition and primary production, according to food web theory. Empirical knowledge of such an effect in freshwater systems is limited, but it has been suggested that predators in odd-numbered food chains suppress freshwater carbon dioxide emissions, and predators in even-numbered food chains enhance emissions. Here, we report experiments in three-tier food chains in experimental ponds, streams and bromeliads in Canada and Costa Rica in the presence or absence of fish (Gasterosteus aculeatus) and invertebrate (Hesperoperla pacifica and Mecistogaster modesta) predators. We monitored carbon dioxide fluxes along with prey and primary producer biomass. We found substantially reduced carbon dioxide emissions in the presence of predators in all systems, despite differences in predator type, hydrology, climatic region, ecological zone and level of in situ primary production. We also observed lower amounts of prey biomass and higher amounts of algal and detrital biomass in the presence of predators. We conclude that predators have the potential to markedly influence carbon dioxide dynamics in freshwater systems.

Carbon dioxide sequestration by mineral carbonation

NARCIS (Netherlands)

Huijgen, W.J.J.

2007-01-01

The increasing atmospheric carbon dioxide (CO2) concentration, mainly caused by fossil fuel combustion, has lead to concerns about global warming. A possible technology that can contribute to the reduction of carbon dioxide emissions is CO2 sequestration by mineral carbonation. The basic concept

Carbon dioxide dangers demonstration model

Science.gov (United States)

Venezky, Dina; Wessells, Stephen

2010-01-01

Carbon dioxide is a dangerous volcanic gas. When carbon dioxide seeps from the ground, it normally mixes with the air and dissipates rapidly. However, because carbon dioxide gas is heavier than air, it can collect in snowbanks, depressions, and poorly ventilated enclosures posing a potential danger to people and other living things. In this experiment we show how carbon dioxide gas displaces oxygen as it collects in low-lying areas. When carbon dioxide, created by mixing vinegar and baking soda, is added to a bowl with candles of different heights, the flames are extinguished as if by magic.

Carbon Dioxide Embolism during Laparoscopic Surgery

Science.gov (United States)

Park, Eun Young; Kwon, Ja-Young

2012-01-01

Clinically significant carbon dioxide embolism is a rare but potentially fatal complication of anesthesia administered during laparoscopic surgery. Its most common cause is inadvertent injection of carbon dioxide into a large vein, artery or solid organ. This error usually occurs during or shortly after insufflation of carbon dioxide into the body cavity, but may result from direct intravascular insufflation of carbon dioxide during surgery. Clinical presentation of carbon dioxide embolism ranges from asymptomatic to neurologic injury, cardiovascular collapse or even death, which is dependent on the rate and volume of carbon dioxide entrapment and the patient's condition. We reviewed extensive literature regarding carbon dioxide embolism in detail and set out to describe the complication from background to treatment. We hope that the present work will improve our understanding of carbon dioxide embolism during laparoscopic surgery. PMID:22476987

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.

Carbon ion pump for removal of carbon dioxide from combustion gas and other gas mixtures

Energy Technology Data Exchange (ETDEWEB)

Aines, Roger D.; Bourcier, William L.

2014-08-19

A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

Carbon ion pump for removal of carbon dioxide from combustion gas and other gas mixtures

Science.gov (United States)

Aines, Roger D.; Bourcier, William L.

2010-11-09

A novel method and system of separating carbon dioxide from flue gas is introduced. Instead of relying on large temperature or pressure changes to remove carbon dioxide from a solvent used to absorb it from flue gas, the ion pump method, as disclosed herein, dramatically increases the concentration of dissolved carbonate ion in solution. This increases the overlying vapor pressure of carbon dioxide gas, permitting carbon dioxide to be removed from the downstream side of the ion pump as a pure gas. The ion pumping may be obtained from reverse osmosis, electrodialysis, thermal desalination methods, or an ion pump system having an oscillating flow in synchronization with an induced electric field.

Does Carbon Dioxide Predict Temperature?

OpenAIRE

Mytty, Tuukka

2013-01-01

Does carbon dioxide predict temperature? No it does not, in the time period of 1880-2004 with the carbon dioxide and temperature data used in this thesis. According to the Inter Governmental Panel on Climate Change(IPCC) carbon dioxide is the most important factor in raising the global temperature. Therefore, it is reasonable to assume that carbon dioxide truly predicts temperature. Because this paper uses observational data it has to be kept in mind that no causality interpretation can be ma...

Carbon dioxide and future climate

Energy Technology Data Exchange (ETDEWEB)

Mitchell, J M

1977-03-01

The addition of carbon dioxide to the atmosphere due to burning fossil fuel is discussed. The release rate of carbon dioxide has been growing since at least 1950 at an average rate of 4.3% per year. If all known fossil fuel reserves in the world are consumed, a total of between 5 and 14 times the present amount of carbon dioxide in the atmosphere will be released. The oceans would then be unlikely to withdraw the proportion of perhaps 40% which they are believed to have withdrawn up to the present. The increase in the atmosphere would be in excess of 3 times or conceivably ten times the present amount. If the reserves are used up within a few hundred years, more than half the excess carbon dioxide would remain in the atmosphere after a thousand years. The ''greenhouse'' effect of carbon dioxide is explained. The simulation with numerical models of the effects of carbon dioxide on atmospheric radiation fluxes is discussed. An estimated increase in the average annual temperature of the earth of 2.4 to 2.9C is given for doubling the carbon dioxide content; also a 7% increase in global average precipitation. The effect of increasing carbon dioxide on global mean temperature is viewed in the perspective of the glacial-interglacial cycles. The warming effect of carbon dioxide may induce a ''super-interglacial'' on the present interglacial which is expected to decline toward a new ice age in the next several thousand years. Finally it is proposed that it may be necessary to phase out the use of fossil fuels before all the knowledge is acquired which would necessitate such an action.

Potential reduction of carbon dioxide emissions from the use of electric energy storage on a power generation unit/organic Rankine system

International Nuclear Information System (INIS)

Mago, Pedro J.; Luck, Rogelio

2017-01-01

Highlights: • A power generation organic Rankine cycle with electric energy storage is evaluated. • The potential carbon dioxide emissions reduction of the system is evaluated. • The system performance is evaluated for a building in different climate zones. • The system emissions and cost are compared with those of conventional systems. • Use of carbon emissions cap and trade programs on the system is evaluated. - Abstract: This paper evaluates the potential carbon dioxide emissions reduction from the implementation of electric energy storage to a combined power generation unit and an organic Rankine cycle relative to a conventional system that uses utility gas for heating and utility electricity for electricity needs. Results indicate that carbon dioxide emission reductions from the operation of the proposed system are directly correlated to the ratio of the carbon dioxide emission conversion factor for electricity to that of the fuel. The location where the system is installed also has a strong influence on the potential of the proposed system to save carbon dioxide emissions. Finally, it is shown that by using carbon emissions cap and trade programs, it is possible to establish a frame of reference to compare/exchange operational cost gains with carbon dioxide emission reductions/gains.

Hydrodynamic Controls on Carbon Dioxide Efflux from Inland Waters

Science.gov (United States)

Long, H. E.; Waldron, S.; Hoey, T.; Newton, J.; Quemin, S.

2013-12-01

Intensive research has been undertaken on carbon dioxide efflux from lakes, estuaries and oceans, but much less attention has been given to rivers and streams, especially lower order streams. River systems are often over-saturated with carbon dioxide and so tend to act as sources of carbon dioxide to the atmosphere. It has been thought that rivers act as pipes carrying this terrestrial carbon to the oceans. However, recent studies have shown that a significant amount of the carbon is reprocessed within the system in a series of transformations and losses. Fluvial evasion of carbon dioxide is now recognised to be a significant component of carbon cycles, however the factors controlling carbon dioxide efflux and its magnitude remain poorly understood and quantified. This research aims to quantify, and better understand the controls on, freshwater carbon dioxide evasion. Data are presented here from field measurements that commenced in Sept 2013 in two contrasting Scottish rivers: the River Kelvin which has a large (335 km.sq) part-urban catchment with predominantly non-peat soils and Drumtee Water, a small (9.6 km.sq) rural catchment of peat soils and agricultural land. Using a floating chamber with the headspace connected to an infrared gas analyser to measure changes in carbon dioxide concentration, efflux rates from 0.22 - 47.4 μmol CO2/m.sq/sec were measured, these close to the middle of the range of previously reported values. At one site on the River Kelvin in May 2013 an influx of -0.61 - -3.53 μmol CO2/m.sq/sec was recorded. Whereas previous research finds carbon dioxide efflux to increase with decreasing river size and a more organic-rich soil catchment, here the controls on carbon dioxide evasion are similar across the contrasting catchments. Carbon dioxide evasion shows seasonality, with maximum fluxes in the summer months being up to twice as high as the winter maxima. Linear regression demonstrates that evasion increases with increased flow velocity

Carbon dioxide angiography: a simple and safe system of delivery

International Nuclear Information System (INIS)

Cronin, P.; Patel, J.V.; Kessel, D.O.; Robertson, I.; McPherson, S.J.

2005-01-01

Carbon dioxide (CO 2 ) is an established alternate angiographic contrast agent, which can be delivered by pump or hand injection. We describe a simple, safe and inexpensive hand injection system that delivers a known volume of CO 2 at atmospheric pressure and prevents contamination with room air

Process for sequestering carbon dioxide and sulfur dioxide

Science.gov (United States)

Maroto-Valer, M Mercedes [State College, PA; Zhang, Yinzhi [State College, PA; Kuchta, Matthew E [State College, PA; Andresen, John M [State College, PA; Fauth, Dan J [Pittsburgh, PA

2009-10-20

A process for sequestering carbon dioxide, which includes reacting a silicate based material with an acid to form a suspension, and combining the suspension with carbon dioxide to create active carbonation of the silicate-based material, and thereafter producing a metal salt, silica and regenerating the acid in the liquid phase of the suspension.

Carbon dioxide, the feedstock for using renewable energy

Science.gov (United States)

Hashimoto, K.; Kumagai, N.; Izumiya, K.; Kato, Z.

2011-03-01

Extrapolation of world energy consumption between 1990 and 2007 to the future reveals the complete exhaustion of petroleum, natural gas, uranium and coal reserves on Earth in 2040, 2044, 2049 and 2054, respectively. We are proposing global carbon dioxide recycling to use renewable energy so that all people in the whole world can survive. The electricity will be generated by solar cell in deserts and used to produce hydrogen by seawater electrolysis at t nearby desert coasts. Hydrogen, for which no infrastructures of transportation and combustion exist, will be converted to methane at desert coasts by the reaction with carbon dioxide captured by energy consumers. Among systems in global carbon dioxide recycling, seawater electrolysis and carbon dioxide methanation have not been performed industrially. We created energy-saving cathodes for hydrogen production and anodes for oxygen evolution without chlorine formation in seawater electrolysis, and ideal catalysts for methane formation by the reaction of carbon dioxide with hydrogen. Prototype plant and industrial scale pilot plant have been built.

Kinetic of formation for single carbon dioxide and mixed carbon dioxide and tetrahydrofuran hydrates in water and sodium chloride aqueous solution

NARCIS (Netherlands)

Sabil, K.M.; Duarte, A.R.C.; Zevenbergen, J.F.; Ahmad, M.M.; Yusup, S.; Omar, A.A.; Peters, C.J.

2010-01-01

A laboratory-scale reactor system is built and operated to measure the kinetic of formation for single and mixed carbon dioxide-tetrahydrofuran hydrates. The T-cycle method, which is used to collect the kinetic data, is briefly discussed. For single carbon dioxide hydrate, the induction time

77 FR 33859 - Carbon Dioxide Fire Suppression Systems on Commercial Vessels

Science.gov (United States)

2012-06-07

... alternatives suggested using plastic wrap to detect leaks rather than requiring odorizers. This suggestion is... approved alternatives to carbon dioxide systems may be used to protect some spaces on these vessels, and... regulations so that the clean agent systems we have routinely been approving can be used by regulated entities...

Simulation scenarios for rapid reduction in carbon dioxide emissions in the western electricity system

International Nuclear Information System (INIS)

Ford, Andrew

2008-01-01

This paper describes a computer simulation analysis of carbon dioxide emissions in the electric power system in the western United States. Legislation at both the state and federal level would impose a price on emissions via cap-and-trade in allowances for carbon dioxide emissions. The simulation scenarios for the western system indicate that dramatic reductions in emissions are possible with generating technologies that exist today. Wind and biomass generators play a key role even with conservative assumptions about their future costs. In contrast, generation from advanced technologies provide only a minor contribution by the year 2025. These scenarios provide support to those who argue that the US should move expeditiously to put a price on carbon dixoide emissions

Carbon dioxide stripping in aquaculture. part 1: terminology and reporting

Science.gov (United States)

Colt, John; Watten, Barnaby; Pfeiffer, Tim

2012-01-01

The removal of carbon dioxide gas in aquacultural systems is much more complex than for oxygen or nitrogen gas because of liquid reactions of carbon dioxide and their kinetics. Almost all published carbon dioxide removal information for aquaculture is based on the apparent removal value after the CO2(aq) + HOH ⇔ H2CO3 reaction has reached equilibrium. The true carbon dioxide removal is larger than the apparent value, especially for high alkalinities and seawater. For low alkalinity freshwaters (<2000 μeq/kg), the difference between the true and apparent removal is small and can be ignored for many applications. Analytical and reporting standards are recommended to improve our understanding of carbon dioxide removal.

Flexible substrates as basis for photocatalytic reduction of carbon dioxide

DEFF Research Database (Denmark)

Jensen, Jacob; Mikkelsen, Mette; Krebs, Frederik C

2011-01-01

A photocatalytic system for converting carbon dioxide into carbon monoxide was designed and constructed. The system relies on thin films of the photocatalyst prepared at low temperature using spray coating. We formulated inks based on the well-known photocatalyst titanium dioxide and characterized...

A review on photo-thermal catalytic conversion of carbon dioxide

Directory of Open Access Journals (Sweden)

Ee Teng Kho

2017-07-01

Full Text Available The conversion of carbon dioxide into value-added products is of great industrial and environmental interest. However, as carbon dioxide is relatively stable, the input energy required for this conversion is a significant limiting factor in the system's performance. By utilising energy from the sun, through a range of key routes, this limitation can be overcome. In this review, we present a comprehensive and critical overview of the potential routes to harvest the sun's energy, primarily through solar-thermal technologies and plasmonic resonance effects. Focusing on the localised heating approach, this review shortlists and compares viable catalysts for the photo-thermal catalytic conversion of carbon dioxide. Further, the pathways and potential products of different carbon dioxide conversion routes are outlined with the reverse water gas shift, methanation, and methanol synthesis being of key interest. Finally, the challenges in implementing such systems and the outlook to the future are detailed. Keywords: Carbon dioxide conversion, Photo-thermal, Plasmonic catalysis, Solar thermal

Energy Saving High-Capacity Moderate Pressure Carbon Dioxide Storage System, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Our approach to high-pressure carbon dioxide storage will directly address the challenges associated with storage of compressed carbon dioxide - the need to reduce...

21 CFR 184.1240 - Carbon dioxide.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 3 2010-04-01 2009-04-01 true Carbon dioxide. 184.1240 Section 184.1240 Food and... Substances Affirmed as GRAS § 184.1240 Carbon dioxide. (a) Carbon dioxide (empirical formula CO2, CAS Reg. No.... The solid form, dry ice, sublimes under atmospheric pressure at a temperature of −78.5 °C. Carbon...

Incentives of carbon dioxide regulation for investment in low-carbon electricity technologies in Texas

International Nuclear Information System (INIS)

Castillo, Anya; Linn, Joshua

2011-01-01

This paper compares the incentives a carbon dioxide emissions price creates for investment in low carbon dioxide-emitting technologies in the electricity sector. We consider the extent to which operational differences across generation technologies - particularly, nuclear, wind and solar photovoltaic - create differences in the incentives for new investment, which is measured by the operating profits of a potential entrant. First, astylized model of an electricity system demonstrates that the composition of the existing generation system may cause electricity prices to increase by different amounts over time when a carbon dioxide price is imposed. Differences in operation across technologies therefore translate to differences in the operating profits of a potential entrant. Then, a detailed simulation model is used to consider a hypothetical carbon dioxide price of $10-$50 per metric ton for the Electric Reliability Council of Texas (ERCOT) market. The simulations show that, for the range of prices considered, the increase in electricity prices is positively correlated with output from a typical wind unit, but the correlation is much weaker for nuclear and photovoltaic. Consequently, a carbon dioxide price creates much stronger investment incentives for wind than for nuclear or photovoltaic technologies in the Texas market. - Highlights: → Compare incentives for new investment in low-emission electricity technologies created by carbon dioxide price. → Focus on ERCOT power system using stochastic unit commitment model. →Find a greater incentive for wind than solar or nuclear because of correlation between wind generation and increase in electricity prices.

Carbon dioxide and climate

International Nuclear Information System (INIS)

1991-10-01

Global climate change is a serious environmental concern, and the US has developed ''An Action Agenda'' to deal with it. At the heart of the US effort is the US Global Change Research Program (USGCRP), which has been developed by the Committee on Earth and Environmental Sciences (CEES) of the Federal Coordinating Council for Sciences, Engineering, and Technology (FCCSET). The USGCRP will provide the scientific basis for sound policy making on the climate-change issue. The DOE contribution to the USGCRP is the Carbon Dioxide Research Program, which now places particular emphasis on the rapid improvement of the capability to predict global and regional climate change. DOE's Carbon Dioxide Research Program has been addressing the carbon dioxide-climate change connection for more than twelve years and has provided a solid scientific foundation for the USGCRP. The expansion of the DOE effort reflects the increased attention that the Department has placed on the issue and is reflected in the National Energy Strategy (NES) that was released in 1991. This Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1991 and gives a brief overview of objectives, organization, and accomplishments. The Environmental Sciences Division of the Office of Health and Environmental Research, Office of Energy Research supports a Carbon Dioxide Research Program to determine the scientific linkage between the rise of greenhouse gases in the atmosphere, especially carbon dioxide, and climate and vegetation change. One facet is the Core CO 2 Program, a pioneering program that DOE established more than 10 years ago to understand and predict the ways that fossil-fuel burning could affect atmospheric CO 2 concentration, global climate, and the Earth's biosphere. Major research areas are: global carbon cycle; climate detection and models of climate change; vegetation research; resource analysis; and, information and integration

46 CFR 108.627 - Carbon dioxide alarm.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Carbon dioxide alarm. 108.627 Section 108.627 Shipping... EQUIPMENT Equipment Markings and Instructions § 108.627 Carbon dioxide alarm. Each carbon dioxide alarm must be identified by marking: “WHEN ALARM SOUNDS VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED” next to...

Oxygen and carbon dioxide sensing

Science.gov (United States)

Ren, Fan (Inventor); Pearton, Stephen John (Inventor)

2012-01-01

A high electron mobility transistor (HEMT) capable of performing as a CO.sub.2 or O.sub.2 sensor is disclosed, hi one implementation, a polymer solar cell can be connected to the HEMT for use in an infrared detection system. In a second implementation, a selective recognition layer can be provided on a gate region of the HEMT. For carbon dioxide sensing, the selective recognition layer can be, in one example, PEI/starch. For oxygen sensing, the selective recognition layer can be, in one example, indium zinc oxide (IZO). In one application, the HEMTs can be used for the detection of carbon dioxide and oxygen in exhaled breath or blood.

High Pressure Vapor-Liquid Equilibrium of Supercritical Carbon Dioxide + n-Hexane System

Institute of Scientific and Technical Information of China (English)

YU Jinglin; TIAN Yiling; ZHU Rongjiao; LIU Zhihua

2006-01-01

Vapor-liquid equilibrium data of supercritical carbon dioxide + n-hexane system were measured at 313.15 K,333.15 K,353.15 K,and 373.15 K and their molar volumes and densities were measured both in the subcritical and supercritical regions ranging from 2.15 to 12.63 MPa using a variable-volume autoclave.The thermodynamic properties including mole fractions,densities,and molar volumes of the system were calculated with an equation of state by Heilig and Franck,in which a repulsion term and a square-well potential attraction term for intermolecular interaction was used.The pairwise combination rule was used to calculate the square-well molecular interaction potential and three adjustable parameters (ω,kε,kσ) were obtained.The Heilig-Franck equation of state is found to have good correlation with binary vapor-liquid equilibrium data of the carbon dioxide + n-hexane system.

CARBON DIOXIDE AS A FEEDSTOCK.

Energy Technology Data Exchange (ETDEWEB)

CREUTZ,C.; FUJITA,E.

2000-12-09

This report is an overview on the subject of carbon dioxide as a starting material for organic syntheses of potential commercial interest and the utilization of carbon dioxide as a substrate for fuel production. It draws extensively on literature sources, particularly on the report of a 1999 Workshop on the subject of catalysis in carbon dioxide utilization, but with emphasis on systems of most interest to us. Atmospheric carbon dioxide is an abundant (750 billion tons in atmosphere), but dilute source of carbon (only 0.036 % by volume), so technologies for utilization at the production source are crucial for both sequestration and utilization. Sequestration--such as pumping CO{sub 2} into sea or the earth--is beyond the scope of this report, except where it overlaps utilization, for example in converting CO{sub 2} to polymers. But sequestration dominates current thinking on short term solutions to global warming, as should be clear from reports from this and other workshops. The 3500 million tons estimated to be added to the atmosphere annually at present can be compared to the 110 million tons used to produce chemicals, chiefly urea (75 million tons), salicylic acid, cyclic carbonates and polycarbonates. Increased utilization of CO{sub 2} as a starting material is, however, highly desirable, because it is an inexpensive, non-toxic starting material. There are ongoing efforts to replace phosgene as a starting material. Creation of new materials and markets for them will increase this utilization, producing an increasingly positive, albeit small impact on global CO{sub 2} levels. The other uses of interest are utilization as a solvent and for fuel production and these will be discussed in turn.

21 CFR 582.1240 - Carbon dioxide.

Science.gov (United States)

2010-04-01

... 21 Food and Drugs 6 2010-04-01 2010-04-01 false Carbon dioxide. 582.1240 Section 582.1240 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) ANIMAL DRUGS....1240 Carbon dioxide. (a) Product. Carbon dioxide. (b) Conditions of use. This substance is generally...

Perspectives in the use of carbon dioxide

Directory of Open Access Journals (Sweden)

Aresta Michele

1999-01-01

Full Text Available The mitigation of carbon dioxide is one of the scientific and technological challenges of the 2000s. Among the technologies that are under assessment, the recovery of carbon dioxide from power plants or industrial flue gases plays a strategic role. Recovered carbon dioxide can be either disposed in natural fields or used. The availability of large amounts of carbon dioxide may open new routes to its utilisation in biological, chemical and innovative technological processes. In this paper, the potential of carbon dioxide utilisation in the short-, medium-term is reviewed.

Phase equilibrium condition of marine carbon dioxide hydrate

International Nuclear Information System (INIS)

Sun, Shi-Cai; Liu, Chang-Ling; Ye, Yu-Guang

2013-01-01

Highlights: ► CO 2 hydrate phase equilibrium was studied in simulated marine sediments. ► CO 2 hydrate equilibrium temperature in NaCl and submarine pore water was depressed. ► Coarse-grained silica sand does not affect CO 2 hydrate phase equilibrium. ► The relationship between equilibrium temperature and freezing point was discussed. - Abstract: The phase equilibrium of ocean carbon dioxide hydrate should be understood for ocean storage of carbon dioxide. In this paper, the isochoric multi-step heating dissociation method was employed to investigate the phase equilibrium of carbon dioxide hydrate in a variety of systems (NaCl solution, submarine pore water, silica sand + NaCl solution mixture). The experimental results show that the depression in the phase equilibrium temperature of carbon dioxide hydrate in NaCl solution is caused mainly by Cl − ion. The relationship between the equilibrium temperature and freezing point in NaCl solution was discussed. The phase equilibrium temperature of carbon dioxide hydrate in submarine pore water is shifted by −1.1 K to lower temperature region than that in pure water. However, the phase equilibrium temperature of carbon dioxide hydrate in mixture samples of coarsed-grained silica sand and NaCl solution is in agreement with that in NaCl solution with corresponding concentrations. The relationship between the equilibrium temperature and freezing point in mixture samples was also discussed.

Development and design of a high pressure carbon dioxide system for the separation of hazardous contaminants from non-hazardous debris

International Nuclear Information System (INIS)

Adkins, C.L.J.; Russick, E.M.; Smith, H.M.; Olson, R.B.

1995-01-01

Under the Department of Energy (DOE)/United States Air Force (USAF) Memorandum of Understanding, a system is being designed that will use high pressure carbon dioxide for the separation of oils, greases, and solvents from non-hazardous solid waste. The contaminants are dissolved into the high pressure carbon dioxide and precipitated out upon depressurization. The carbon dioxide solvent can then be recycled for continued use. Excellent extraction capability for common manufacturing oils, greases, and solvents has been measured. It has been observed that extraction performance follows the dilution model if a constant flow system is used. The solvents tested are extremely soluble and have been extracted to 100% under both liquid and mild supercritical carbon dioxide conditions. These data are being used to design a 200 liter extraction system

The impact of environmental factors on carbon dioxide fixation by microalgae.

Science.gov (United States)

Morales, Marcia; Sánchez, León; Revah, Sergio

2018-02-01

Microalgae are among the most productive biological systems for converting sunlight into chemical energy, which is used to capture and transform inorganic carbon into biomass. The efficiency of carbon dioxide capture depends on the cultivation system configuration (photobioreactors or open systems) and can vary according to the state of the algal physiology, the chemical composition of the nutrient medium, and environmental factors such as irradiance, temperature and pH. This mini-review is focused on some of the most important environmental factors determining photosynthetic activity, carbon dioxide biofixation, cell growth rate and biomass productivity by microalgae. These include carbon dioxide and O2 concentrations, light intensity, cultivation temperature and nutrients. Finally, a review of the operation of microalgal cultivation systems outdoors is presented as an example of the impact of environmental conditions on biomass productivity and carbon dioxide fixation. © FEMS 2017. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

Modelling of tetrahydrofuran promoted gas hydrate systems for carbon dioxide capture processes

DEFF Research Database (Denmark)

Herslund, Peter Jørgensen; Thomsen, Kaj; Abildskov, Jens

2014-01-01

A thermodynamic study of a novel gas hydrate based CO2 capture process is presented.•Model predicts this process unsuitable for CO2 capture from power station flue gases. A thermodynamic modelling study of both fluid phase behaviour and hydrate phase behaviour is presented for the quaternary system...... of water, tetrahydrofuran, carbon dioxide and nitrogen. The applied model incorporates the Cubic-Plus-Association (CPA) equation of state for the fluid phase description and the van der Waals-Platteeuw hydrate model for the solid (hydrate) phase. Six binary pairs are studied for their fluid phase behaviour...... accurate descriptions of both fluid- and hydrate phase equilibria in the studied system and its subsystems. The developed model is applied to simulate two simplified, gas hydrate-based processes for post-combustion carbon dioxide capture from power station flue gases. The first process, an unpromoted...

Balancing atmospheric carbon dioxide

Energy Technology Data Exchange (ETDEWEB)

Goreau, T.J. (Discovery Bay Marine Laboratory, Univ. of the West Indies (JM))

1990-01-01

Rising carbon dioxide and global temperatures are causing increasing worldwide concern, and pressure towards an international law of the atmosphere is rapidly escalating, yet widespread misconceptions about the greenhouse effect's inevitability, time scale, and causes have inhibited effective consensus and action. Observations from Antarctic ice cores, Amazonian rain forests, and Carribean coral reefs suggest that the biological effects of climate change may be more severe than climate models predict. Efforts to limit emissions from fossil-fuel combustion alone are incapable of stabilizing levels of carbon dioxide in the atmosphere. Stabilizing atmospheric carbon dioxide requires coupled measures to balance sources and sinks of the gas, and will only be viable with large-scale investments in increased sustainable productivity on degraded tropical soils, and in long-term research on renewable energy and biomass product development in the developing countries. A mechanism is outlined which directly links fossil-fuel combustion sources of carbon dioxide to removal via increasing biotic productivity and storage. A preliminary cost-benefit analysis suggests that such measures are very affordable, costing far less than inaction. (With 88 refs.).

Balancing atmospheric carbon dioxide

Energy Technology Data Exchange (ETDEWEB)

Goreau, T J [Discovery Bay Marine Laboratory, Univ. of the West Indies (JM)

1990-01-01

Rising carbon dioxide and global temperatures are causing increasing worldwide concern, and pressure towards an international law of the atmosphere is rapidly escalating, yet widespread misconceptions about the greenhouse effect's inevitability, time scale, and causes have inhibited effective consensus and action. Observations from Antarctic ice cores, Amazonian rain forests, and Carribean coral reefs suggest that the biological effects of climate change may be more severe than climate models predict. Efforts to limit emissions from fossil-fuel combustion alone are incapable of stabilizing levels of carbon dioxide in the atmosphere. Stabilizing atmospheric carbon dioxide requires coupled measures to balance sources and sinks of the gas, and will only be viable with large-scale investments in increased sustainable productivity on degraded tropical soils, and in long-term research on renewable energy and biomass product development in the developing countries. A mechanism is outlined which directly links fossil-fuel combustion sources of carbon dioxide to removal via increasing biotic productivity and storage. A preliminary cost-benefit analysis suggests that such measures are very affordable, costing far less than inaction. (With 88 refs.).

Model studies of limitation of carbon dioxide emissions reduction

International Nuclear Information System (INIS)

1992-01-01

The report consists of two papers concerning mitigation of CO 2 emissions in Sweden, ''Limitation of carbon dioxide emissions. Socio-economic effects and the importance of international coordination'', and ''Model calculations for Sweden's energy system with carbon dioxide limitations''. Separate abstracts were prepared for both of the papers

Decontamination of radioactive clothing using microemulsion in carbon dioxide

Energy Technology Data Exchange (ETDEWEB)

Yoo, Jaeryong; Jang, Jina; Park, Kwangheon; Kim, Hongdoo; Kim, Hakwon [Kyunghee Univ., Seoul (Korea, Republic of); Yim, Sanghak; Yoon, Weonseob [Ulchin Nuclear Power Site, Ulchin (Korea, Republic of)

2006-07-01

Nuclear power is intrinsically a clean energy source due to its high energy density and low generation of waste. However, as the nuclear industry grows, a variety of radioactive wastes are increased gradually. Major subjects include contaminated components, tools, equipment, containers and facilities as well as nuclear waste such as uranium scrap and radioactive clothing. The radioactive waste can be classified by its creation. There are Trans-Uranium Nuclides (TRU), Fission Products (FP) and corrosion products. Nuclear decontamination has become an important issue in the nuclear industry. The conventional methods have some problems such as the production of secondary wastes and the use of toxic solvents. We need to develop a new method of decontamination and suggest a use of microemulsion in carbon dioxide to overcome these disadvantages. The microemulsion is the clear solution that contains the water, surfactant and carbon dioxide. The surfactant surrounded the droplet into carbon dioxide and this state is thermodynamically stable. That is, the microemulsion has a structure similar to that of a conventional water-based surfactant system. Generally, the size of droplet is about 5 {approx} 10nm. The microemulsion is able to decontaminate radioactive waste so that the polar substance is removed by water and the non-polar substance is removed by carbon dioxide. After the decontamination process, the microemulsion is separated easily to surfactant and water by decreasing the pressure under the cloud point. This way, only radioactive wastes are left in the system. Cleaned carbon dioxide is then collected and reused. Thus, there are no secondary wastes. Carbon dioxide is considered an alternative process medium. This is because it is non-toxic, non-flammable, inexpensive and easy to handle. Additionally, the tunable properties of carbon dioxide through pressure and temperature control are versatile for use in extracting organic materials. In this paper, we examine the

Decontamination of radioactive clothing using microemulsion in carbon dioxide

International Nuclear Information System (INIS)

Yoo, Jaeryong; Jang, Jina; Park, Kwangheon; Kim, Hongdoo; Kim, Hakwon; Yim, Sanghak; Yoon, Weonseob

2006-01-01

Nuclear power is intrinsically a clean energy source due to its high energy density and low generation of waste. However, as the nuclear industry grows, a variety of radioactive wastes are increased gradually. Major subjects include contaminated components, tools, equipment, containers and facilities as well as nuclear waste such as uranium scrap and radioactive clothing. The radioactive waste can be classified by its creation. There are Trans-Uranium Nuclides (TRU), Fission Products (FP) and corrosion products. Nuclear decontamination has become an important issue in the nuclear industry. The conventional methods have some problems such as the production of secondary wastes and the use of toxic solvents. We need to develop a new method of decontamination and suggest a use of microemulsion in carbon dioxide to overcome these disadvantages. The microemulsion is the clear solution that contains the water, surfactant and carbon dioxide. The surfactant surrounded the droplet into carbon dioxide and this state is thermodynamically stable. That is, the microemulsion has a structure similar to that of a conventional water-based surfactant system. Generally, the size of droplet is about 5 ∼ 10nm. The microemulsion is able to decontaminate radioactive waste so that the polar substance is removed by water and the non-polar substance is removed by carbon dioxide. After the decontamination process, the microemulsion is separated easily to surfactant and water by decreasing the pressure under the cloud point. This way, only radioactive wastes are left in the system. Cleaned carbon dioxide is then collected and reused. Thus, there are no secondary wastes. Carbon dioxide is considered an alternative process medium. This is because it is non-toxic, non-flammable, inexpensive and easy to handle. Additionally, the tunable properties of carbon dioxide through pressure and temperature control are versatile for use in extracting organic materials. In this paper, we examine the

Fixation of carbon dioxide into dimethyl carbonate over ...

Science.gov (United States)

A titanium-based zeolitic thiophene-benzimidazolate framework has been designed for the direct synthesis of dimethyl carbonate (DMC) from methanol and carbon dioxide. The developed catalyst activates carbon dioxide and delivers over 16% yield of DMC without the use of any dehydrating agent or requirement for azeotropic distillation. Prepared for submission to Nature Scientific reports.

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.

World-Economy Centrality and Carbon Dioxide Emissions: A New Look at the Position in the Capitalist World-System and Environmental Pollution

Directory of Open Access Journals (Sweden)

Paul Prew

2015-08-01

Full Text Available With the ever-growing concern of climate change, much attention has been paid to the factors driving carbon dioxide emissions. Previous research in the World-Systems perspective has identified a relationship between carbon dioxide emissions and position in the world-economy. This study intends to build on the previous research by developing a new, more parsimonious indicator of World-System position based on Immanuel Wallerstein’s theoretical concepts of incorporation and core-periphery processes. The new World-System indicator is derived from the centrality measure in network analysis based on import data from the International Monetary Fund’s Direction of Trade Statistics. Based on the theoretical concepts of core-periphery processes, carbon dioxide emissions are predicted to rise based on the predominance of energy-intensive, high-technology, core processes within the nation. The results tend to demonstrate a strong relationship between carbon dioxide emissions and position in the world-economy, and the new World-System position indicator is more strongly related with carbon dioxide emissions than Gross Domestic Product per capita.

Absorption of carbon dioxide in waste tanks

International Nuclear Information System (INIS)

Hobbs, D.T.

1987-01-01

Air flow rates and carbon dioxide concentrations of air entering and exiting eight H-Area waste tanks were monitored for a period of one year. The average instanteous concentration of carbon dioxide in air is within the range reported offsite, and therefore is not affect by operation of the coal-fired power plant adjacent to the tank farm. Waste solutions in each of the tanks were observed to be continuously absorbing carbon dioxide. The rate of absorption of carbon dioxide decreased linearly with the pH of the solution. Personnel exposure associated with the routine sampling and analysis of radioactive wastes stored at SRP to determine the levels of corrosion inhibitors in solution could be reduced by monitoring the absorption of carbon dioxide and using the relationship between pH and carbon dioxide absorption to determine the free hydroxide concentration in solution

Carbon dioxide production in animal houses

DEFF Research Database (Denmark)

Pedersen, Søren; Blanes-Vidal, Victoria; Joergensen, H.

2008-01-01

cellars are emptied regularly in a four weeks interval. Due to a high and variable carbon dioxide production in deep straw litter houses and houses with indoor storage of manure longer than four weeks, we do not recommend to calculate the ventilation flow based on the carbon dioxide concentration......This article deals with carbon dioxide production from farm animals; more specifically, it addresses the possibilities of using the measured carbon dioxide concentration in animal houses as basis for estimation of ventilation flow (as the ventilation flow is a key parameter of aerial emissions from...... animal houses). The investigations include measurements in respiration chambers and in animal houses, mainly for growing pigs and broilers. Over the last decade a fixed carbon dioxide production of 185 litres per hour per heat production unit, hpu (i.e. 1000 W of the total animal heat production at 20o...

Carbon isotope ratios of atmospheric carbon dioxide

International Nuclear Information System (INIS)

Sakai, Hitoshi; Kishima, Noriaki; Tsutaki, Yasuhiro.

1982-01-01

The delta 13 C values relative to PDB were measured for carbon dioxide in air samples collected at various parts of Japan and at Mauna Loa Observatory, Hawaii in the periods of 1977 and 1978. The delta 13 C values of the ''clean air'' are -7.6 % at Hawaii and -8.1 per mille Oki and Hachijo-jima islands. These values are definitely lighter than the carbon isotope ratios (-6.9 per mille) obtained by Keeling for clean airs collected at Southern California in 1955 to 1956. The increase in 12 C in atmospheric carbon dioxide is attributed to the input of the anthropogenic light carbon dioxides (combustion of fossil fuels etc.) Taking -7.6 per mille to be the isotope ratio of CO 2 in the present clean air, a simple three box model predicts that the biosphere has decreased rather than increased since 1955, implying that it is acting as the doner of carbon rather than the sink. (author)

Derived thermodynamic properties for the (ethanol + decane) and (carbon dioxide + ethanol + decane) systems at high pressures

International Nuclear Information System (INIS)

Zamora-López, Héctor S.; Galicia-Luna, Luis A.; Elizalde-Solis, Octavio; Hernández-Rosales, Irma P.; Méndez-Lango, Edgar

2012-01-01

Highlights: ► Experimental density data are reported for (ethanol + decane) and (ethanol + decane + CO 2 ) mixtures. ► Compressed liquid densities were measured in a vibrating tube densimeter from (313 to 363) K. ► Excess molar volumes for (ethanol + decane) mixtures are positive. ► The presence of carbon dioxide in the (ethanol + decane) mixture causes negative excess molar volumes. - Abstract: Volumetric properties for the binary (ethanol + decane) and ternary (ethanol + decane + carbon dioxide) systems are reported from (313 to 363) K and pressures up to 20 MPa. Compressed liquid densities of both systems were measured in a vibrating tube densimeter at different compositions. Binary mixtures {x 1 ethanol + (1-x 1 ) decane} were prepared at x 1 = 0.0937, 0.1011, 0.2507, 0.4963, 0.7526, 0.9014. Compositions for the ternary system were prepared by varying the ethanol/decane relation and trying to keep constant the presence of carbon dioxide at about 0.2 mole fraction. These were {x 1 ethanol + x 2 decane + (1-x 1 -x 2 ) carbon dioxide} x 1 = 0.0657, 0.1986, 0.4087, 0.6042, 0.7109. Density results were correlated using an empirical model with five parameters. Deviations between experimental and calculated values agree and are within the experimental uncertainty. Isobaric expansivity, isothermal compressibility, thermal pressure coefficient, and internal pressure have been calculated for both binary and ternary systems using the empirical model.

Report of the Carbon Dioxide Committee II

International Nuclear Information System (INIS)

1994-01-01

The Carbon Dioxide Committee was given the task of preparing a suggestion of the acts aimed at reducing the greenhouse gas emissions and increasing the sinks of carbon in Finland. Emissions of all greenhouse gases were in 1990 80 million tons. calculated as carbon dioxide. The carbon dioxide emissions were about 58 million tons of the total. The increase of forest resources binds carbon from the atmosphere and reduces thereby net emissions of Finland at present by nearly 30 million tons of carbon dioxide. Carbon dioxide emissions will grow during the next decades, unless strong measures to control them will not be taken. As a result of the Commissions examination, acts will be needed both in the production of energy and in its consumption. Emissions can be reduced by replacing fossil fuels with nuclear energy, bioenergy and other renewable energy sources. Saving of energy and improvement of energy efficiency will limit carbon dioxide emissions. The Commission has made suggestions both to change the structure of energy production and to control the consumption of energy. (orig.)

Reducing carbon dioxide to products

Science.gov (United States)

Cole, Emily Barton; Sivasankar, Narayanappa; Parajuli, Rishi; Keets, Kate A

2014-09-30

A method reducing carbon dioxide to one or more products may include steps (A) to (C). Step (A) may bubble said carbon dioxide into a solution of an electrolyte and a catalyst in a divided electrochemical cell. The divided electrochemical cell may include an anode in a first cell compartment and a cathode in a second cell compartment. The cathode may reduce said carbon dioxide into said products. Step (B) may adjust one or more of (a) a cathode material, (b) a surface morphology of said cathode, (c) said electrolyte, (d) a manner in which said carbon dioxide is bubbled, (e), a pH level of said solution, and (f) an electrical potential of said divided electrochemical cell, to vary at least one of (i) which of said products is produced and (ii) a faradaic yield of said products. Step (C) may separate said products from said solution.

Capacitance-Assisted Sustainable Electrochemical Carbon Dioxide Mineralisation.

Science.gov (United States)

Lamb, Katie J; Dowsett, Mark R; Chatzipanagis, Konstantinos; Scullion, Zhan Wei; Kröger, Roland; Lee, James D; Aguiar, Pedro M; North, Michael; Parkin, Alison

2018-01-10

An electrochemical cell comprising a novel dual-component graphite and Earth-crust abundant metal anode, a hydrogen producing cathode and an aqueous sodium chloride electrolyte was constructed and used for carbon dioxide mineralisation. Under an atmosphere of 5 % carbon dioxide in nitrogen, the cell exhibited both capacitive and oxidative electrochemistry at the anode. The graphite acted as a supercapacitive reagent concentrator, pumping carbon dioxide into aqueous solution as hydrogen carbonate. Simultaneous oxidation of the anodic metal generated cations, which reacted with the hydrogen carbonate to give mineralised carbon dioxide. Whilst conventional electrochemical carbon dioxide reduction requires hydrogen, this cell generates hydrogen at the cathode. Carbon capture can be achieved in a highly sustainable manner using scrap metal within the anode, seawater as the electrolyte, an industrially relevant gas stream and a solar panel as an effective zero-carbon energy source. © 2017 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

Self-Cleaning Boudouard Reactor for Full Oxygen Recovery from Carbon Dioxide

Science.gov (United States)

Coutts, Janelle; Hintze, Paul E.; Muscatello, Anthony C.; Gibson, Tracy L.; Captain, James G.; Lunn, Griffin M.; Devor, Robert W.; Bauer, Brint; Parks, Steve

2016-01-01

Oxygen recovery from respiratory carbon dioxide is an important aspect of human spaceflight. Methods exist to sequester the carbon dioxide, but production of oxygen needs further development. The current International Space Station Carbon Dioxide Reduction System (CRS) uses the Sabatier reaction to produce water (and ultimately breathing air). Oxygen recovery is limited to 50 because half of the hydrogen used in the Sabatier reactor is lost as methane, which is vented overboard. The Bosch reaction, which converts carbon dioxide to oxygen and solid carbon is capable of recovering all the oxygen from carbon dioxide, and is the only real alternative to the Sabatier reaction. However, the last reaction in the cycle, the Boudouard reaction, produces solid carbon and the resulting carbon buildup will eventually foul the nickel or iron catalyst, reducing reactor life and increasing consumables. To minimize this fouling and increase efficiency, a number of self-cleaning catalyst designs have been created. This paper will describe recent results evaluating one of the designs.

Carbon dioxide sequestration by aqueous mineral carbonation of magnesium silicate minerals

Energy Technology Data Exchange (ETDEWEB)

Gerdemann, Stephen J.; Dahlin, David C.; O' Connor, William K.; Penner, Larry R.

2003-01-01

The dramatic increase in atmospheric carbon dioxide since the Industrial Revolution has caused concerns about global warming. Fossil-fuel-fired power plants contribute approximately one third of the total human-caused emissions of carbon dioxide. Increased efficiency of these power plants will have a large impact on carbon dioxide emissions, but additional measures will be needed to slow or stop the projected increase in the concentration of atmospheric carbon dioxide. By accelerating the naturally occurring carbonation of magnesium silicate minerals it is possible to sequester carbon dioxide in the geologically stable mineral magnesite (MgCO3). The carbonation of two classes of magnesium silicate minerals, olivine (Mg2SiO4) and serpentine (Mg3Si2O5(OH)4), was investigated in an aqueous process. The slow natural geologic process that converts both of these minerals to magnesite can be accelerated by increasing the surface area, increasing the activity of carbon dioxide in the solution, introducing imperfections into the crystal lattice by high-energy attrition grinding, and in the case of serpentine, by thermally activating the mineral by removing the chemically bound water. The effect of temperature is complex because it affects both the solubility of carbon dioxide and the rate of mineral dissolution in opposing fashions. Thus an optimum temperature for carbonation of olivine is approximately 185 degrees C and 155 degrees C for serpentine. This paper will elucidate the interaction of these variables and use kinetic studies to propose a process for the sequestration of the carbon dioxide.

46 CFR 97.37-9 - Carbon dioxide alarm.

Science.gov (United States)

2010-10-01

... 46 Shipping 4 2010-10-01 2010-10-01 false Carbon dioxide alarm. 97.37-9 Section 97.37-9 Shipping... Markings for Fire and Emergency Equipment, Etc. § 97.37-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING...

46 CFR 78.47-9 - Carbon dioxide alarm.

Science.gov (United States)

2010-10-01

... 46 Shipping 3 2010-10-01 2010-10-01 false Carbon dioxide alarm. 78.47-9 Section 78.47-9 Shipping... and Emergency Equipment, Etc. § 78.47-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING RELEASED.” (b) [Reserved] ...

46 CFR 196.37-9 - Carbon dioxide alarm.

Science.gov (United States)

2010-10-01

... 46 Shipping 7 2010-10-01 2010-10-01 false Carbon dioxide alarm. 196.37-9 Section 196.37-9 Shipping... Markings for Fire and Emergency Equipment, etc. § 196.37-9 Carbon dioxide alarm. (a) All carbon dioxide alarms shall be conspicuously identified: “WHEN ALARM SOUNDS—VACATE AT ONCE. CARBON DIOXIDE BEING...

Bubble-point measurement for the binary mixture of propargyl acrylate and propargyl methacrylate in supercritical carbon dioxide

International Nuclear Information System (INIS)

Baek, Seung-Hyun; Byun, Hun-Soo

2016-01-01

Highlights: • Phase behaviours for the (CO_2 + propargyl (meth)acrylate) systems by static method were measured. • (P, x) isotherms is obtained at pressures up to 19.14 MPa and at temperature of (313.2 to 393.2) K. • The (CO_2 + propargyl acrylate) and (CO_2 + propargyl methacrylate) systems exhibit type-I behaviour. - Abstract: Acrylate and methacrylate (acrylic acid type) are compounds with weak polarity which show a non-ideal behaviour. Phase behaviour of these systems play a significant role as organic solvents in industrial processes. High pressure phase behaviour data were reported for binary mixture of propargyl acrylate and propargyl methacrylate in supercritical carbon dioxide. The bubble-point curves for the (carbon dioxide + propargyl acrylate) and (carbon dioxide + propargyl methacrylate) mixtures were measured by static view cell apparatus at temperature range from 313.2 K to 393.2 K and at pressures below 19.14 MPa. The (carbon dioxide + propargyl acrylate) and (carbon dioxide + propargyl methacrylate) systems exhibit type-I phase behaviour. The (carbon dioxide + (meth)acrylate) systems had continuous critical mixture curves with maximums in pressure located between the critical temperatures of carbon dioxide and propargyl acrylate or carbon dioxide and propargyl methacrylate. The solubility behaviour of propargyl (meth)acrylate in the (carbon dioxide + propargyl acrylate) and (carbon dioxide + propargyl acrylate) systems increases as the temperature increases at a fixed pressure. The experimental results for the (carbon dioxide + propargyl acrylate) and (carbon dioxide + propargyl methacrylate) systems correlate with the Peng–Robinson equation of state using a van der Waals one-fluid mixing rule. The critical properties of propargyl acrylate and propargyl methacrylate were predicted with the Joback–Lyderson group contribution and Lee–Kesler method.

Amazon River carbon dioxide outgassing fuelled by wetlands

NARCIS (Netherlands)

Abril, G.; Martinez, J.M.; Artigas, L.F.; Moreira-Turcq, P.; Benedetti, M.F.; Vidal, L.; Meziane, T.; Kim, J.-H.; Bernardes, M.C.; Savoye, N.; Deborde, J.; Souza, E.L.; Alberic, P.; de Souza, M.F.L.; Roland, F.

2014-01-01

River systems connect the terrestrial biosphere, the atmosphere and the ocean in the global carbon cycle(1). A recent estimate suggests that up to 3 petagrams of carbon per year could be emitted as carbon dioxide (CO2) from global inland waters, offsetting the carbon uptake by terrestrial

Carbon dioxide: emissions and effects

Energy Technology Data Exchange (ETDEWEB)

Smith, I M

1982-01-01

This review provides a comprehensive guide to work carried out since 1978 in the many disciplines involved in this complex issue. Possible scenarios for carbon dioxide emissions, sources and sinks in the carbon cycle and for climatic changes are examined. The current concensus (by no means unanimous) of specialists on this issue appears to be that a continuation of reduced trends in energy consumption since 1973 is likely to double the atmospheric carbon dioxide concentration to 600 ppmv during the latter part of the next century. However, a higher demand scenario, requiring an upper limit of coal production, would bring forward the doubling to about the middle of the next century. Current climatic models predict that such a concentration of carbon dioxide would cause an average global warming of from 1.0 to 4.5/sup 0/C which might be delayed by the thermal inertia of the oceans. A warming due to estimated increases in carbon dioxide should, if the model results are correct, become apparent at the end of this century. Regional climatic changes are likely to vary considerably and prove disadvantageous to some regions and beneficial to others. Different strategies for dealing with the carbon dioxide issue are considered: no response, alleviation, countermeasures and prevention. It is concluded that uncertainties do not justify either the use of carbon dioxide disposal and other technical fixes at present or a policy of no further growth in fossil fuel consumption. On the other hand, major efforts to conserve energy would give more time to adapt to changes. The alleviation of climatic impacts and other desirable dual-benefit measures are advocated in addition to continuing international, interdisciplinary research on all aspects.

Tethered catalysts for the hydration of carbon dioxide

Science.gov (United States)

Valdez, Carlos A; Satcher, Jr., Joe H; Aines, Roger D; Wong, Sergio E; Baker, Sarah E; Lightstone, Felice C; Stolaroff, Joshuah K

2014-11-04

A system is provided that substantially increases the efficiency of CO.sub.2 capture and removal by positioning a catalyst within an optimal distance from the air-liquid interface. The catalyst is positioned within the layer determined to be the highest concentration of carbon dioxide. A hydrophobic tether is attached to the catalyst and the hydrophobic tether modulates the position of the catalyst within the liquid layer containing the highest concentration of carbon dioxide.

Carbonic acid as a reserve of carbon dioxide on icy moons: The formation of carbon dioxide (CO2) in a polar environment

International Nuclear Information System (INIS)

Jones, Brant M.; Kaiser, Ralf I.; Strazzulla, Giovanni

2014-01-01

Carbon dioxide (CO 2 ) has been detected on the surface of several icy moons of Jupiter and Saturn via observation of the ν 3 band with the Near-Infrared Mapping Spectrometer on board the Galileo spacecraft and the Visible-Infrared Mapping Spectrometer on board the Cassini spacecraft. Interestingly, the CO 2 band for several of these moons exhibits a blueshift along with a broader profile than that seen in laboratory studies and other astrophysical environments. As such, numerous attempts have been made in order to clarify this abnormal behavior; however, it currently lacks an acceptable physical or chemical explanation. We present a rather surprising result pertaining to the synthesis of carbon dioxide in a polar environment. Here, carbonic acid was synthesized in a water (H 2 O)-carbon dioxide (CO 2 ) (1:5) ice mixture exposed to ionizing radiation in the form of 5 keV electrons. The irradiated ice mixture was then annealed, producing pure carbonic acid which was then subsequently irradiated, recycling water and carbon dioxide. However, the observed carbon dioxide ν 3 band matches almost exactly with that observed on Callisto; subsequent temperature program desorption studies reveal that carbon dioxide synthesized under these conditions remains in solid form until 160 K, i.e., the sublimation temperature of water. Consequently, our results suggest that carbon dioxide on Callisto as well as other icy moons is indeed complexed with water rationalizing the shift in peak frequency, broad profile, and the solid state existence on these relatively warm moons.

Laboratory investigations into the reactive transport module of carbon dioxide sequestration and geochemical simulation

Energy Technology Data Exchange (ETDEWEB)

Heidaryan, E. [Islamic Azad Univ., Tehran (Iran, Islamic Republic of). Masjidosolayman Branch; Enayati, M.; Mokhtari, B. [Iranian Offshore Oil Co., Tehran (Iran, Islamic Republic of)

2008-07-01

Over long time periods, geological sequestration in some systems shows mineralization effects or mineral sequestration of carbon dioxide, converting the carbon dioxide to a less mobile form. However, a detailed investigation of these geological systems is needed before disposing of carbon dioxide into these formations. Depleted oil and gas reservoirs and underground aquifers are proposed candidates for carbon dioxide injection. This paper presented an experimental investigation into the reactive transport module for handling aquifer sequestration of carbon dioxide and modeling of simultaneous geochemical reactions. Two cases of laboratory carbon dioxide sequestration experiments, conducted for different rock systems were modeled using the fully coupled geochemical compositional simulator. The relevant permeability relationships were compared to determine the best fit with the experimental results. The paper discussed the theory of modeling; geochemical reactions and mineral trapping of carbon dioxide; and application simulator for modeling including the remodeling of flow experiments. It was concluded that simulated changes in porosity and permeability could mimic experimental results to some extent. The study satisfactorily simulated the results of experimental observations and permeability results could be improved if the Kozeny-Carman equation was replaced by the Civan power law. 6 refs., 2 tabs., 21 figs.

27 CFR 24.319 - Carbon dioxide record.

Science.gov (United States)

2010-04-01

... 27 Alcohol, Tobacco Products and Firearms 1 2010-04-01 2010-04-01 false Carbon dioxide record. 24..., DEPARTMENT OF THE TREASURY LIQUORS WINE Records and Reports § 24.319 Carbon dioxide record. A proprietor who uses carbon dioxide in still wine shall maintain a record of the laboratory tests conducted to...

Extraction of Uranium Using Nitrogen Dioxide and Carbon Dioxide for Spent Fuel Reprocessing

Energy Technology Data Exchange (ETDEWEB)

Kayo Sawada; Daisuke Hirabayashi; Youichi Enokida [EcoTopia Science Institute, Nagoya University, Nagoya, 464-8603 (Japan)

2008-07-01

For the reprocessing of spent nuclear fuels, a new method to extract actinides from spent fuel using highly compressed gases, nitrogen dioxide and carbon dioxide was proposed. Uranium extraction from broken pieces, whose average grain size was 5 mm, of uranium dioxide pellet with nitrogen dioxide and carbon dioxide was demonstrated in the present study. (authors)

Achievement report of projects in fiscal 2000 for measures on technologies to fix and utilize effectively carbon dioxide. Development of program system technologies to fix and utilize effectively carbon dioxide - researches on key technologies (Developing technology to fix carbon dioxide electrochemically); 2000 nendo program hoshiki nisanka tanso koteika yuko riyo gijutsu kaihatsu (kiban gijutsu kenkyu) seika hokokusho (kokaiyo). Nisanka tanso no denki kagakuteki koteika gijutsu no kaihatsu

Energy Technology Data Exchange (ETDEWEB)

NONE

2001-03-01

With an objective to prevent global warming, research and development has been made on a carbon dioxide fixation technology using electrochemical means. This paper summarizes the achievements in fiscal 2000. In the research of a technology to return carbon dioxide to hydrocarbon such as methane electrochemically utilizing the high concentration carbon dioxide-methanol system, basic studies were performed on electrolytic reduction of CO2 using a methanol solvent system, and experimental studies were executed on high-speed reduction of carbon dioxide using gas diffusion electrodes. In the basic property experiment on diamond electrodes, high carbon dioxide reduction activity was obtained by having copper carried in the diamond electrode. In the CO2 electrolytic reduction experiment on three-phase interface using a copper net electrode, CO, ethylene, and methane were produced, while the electrode has retained the activity for an extended period of time, and the CO2 conversion rate reached about 66%. In structuring an electrochemical carbon dioxide fixation system, specifications for the CO2 electrolytic reduction equipment were determined, design, manufacturing, and electrode materials were selected, supporting electrolytes were discussed, and the entire system flow and liquid resistance were discussed. (NEDO)

Measures for carbon dioxide problem and utilization of energy

International Nuclear Information System (INIS)

Kojima, Toshinori

1992-01-01

As global environment problems, there are water, expansion of deserts, weather, tropical forests, wild animals, ocean pollution, nuclear waste contamination, acid rain, ozone layer and so on, and population, foods, energy, and resources are the problems surrounding them. It is clear that these origins are attributed to the development and consumption largely dependent on the intention of developed countries and the population problem of developing countries. In this report, the discharge of carbon dioxide that causes greenhouse effect and its relation with energy are discussed. The increase of carbon dioxide concentration, its release from fossil fuel, the destruction of forests, the balance of carbon on the earth, the development of new energy such as solar energy, the transport of new energy, secondary energy system and the role of carbon dioxide, the transfer to low carbon fuel and the carbon reduction treatment of fuel, the utilization of unused energy and energy price, the efficiency of energy utilization, the heightening of efficiency of energy conversion, energy conservation and the breakaway from energy wasteful use culture, and the recovery, preservation and use of discharged carbon dioxide are described. (K.I.)

Phase aberrations and beam cleanup techniques in carbon-dioxide laser fusion systems

International Nuclear Information System (INIS)

Viswanathan, V.K.

1981-01-01

This paper describes the various carbon dioxide laser fusion systems at Los Alamos from the point of view of an optical designer. The types of phase aberrations present in these systems, as well as the beam cleanup techniques that can be used to improve the beam optical quality, are discussed. As this is a review article, some previously published results are also used where relevant

Effective utilization technology of carbon dioxide. CO sub 2 no yuko riyo gijutsu

Energy Technology Data Exchange (ETDEWEB)

Ibusuki, T. (National Research Inst. for pollution and Resources, Tsukuba (Japan))

1991-03-12

As carbon dioxide-related environmental measures, method was explained to chemically convert and utilize carbon dioxide. Synthesis is possible of methanol, carbon monoxide, different carbohydrates, etc. by catalytic hydrogenation of carbon dioxide, using hydrogen produced by the electrolysis of water. Task consists of heightening in both convertibility and selectivity, and abundant supply of low cost hydrogen. Methane, alcohol, etc. can be synthesized by electrochemical reducion of carbon dioxide. Because of effectively inserting multiple electron, discssion is being made of catalyst, intergrated with electrode, and electron transmitter. The photoelectrochemical reduction of carbon dioxide can be also made by utilizing photoelectric current, generated upon photoradiation on the semiconductive electrode. However, task consists of heightening in both efficiency and selectivity. Photochemical reduction of carbon dioxide, actually made by green plant, consists of oxidationlike decomposition of water and reduction of carbon dioxide. Both those reactions are skillfully separated by intermediation of very quick electron transmission system. Reduction is being studied with semiconductor, metallic colloid, enzyme, metallic complex and other various catalysts. 10 refs., 3 figs., 4 tabs.

Phase behaviour of the ternary system {poly(ε-caprolactone) + carbon dioxide + dichloromethane}

International Nuclear Information System (INIS)

Bender, Joao P.; Feitein, Mirian; Mazutti, Marcio A.; Franceschi, Elton; Corazza, Marcos L.; Oliveira, J. Vladimir

2010-01-01

Recently, production of biocompatible and biodegradable polymer microparticles has been a matter of growing interest in pharmaceutical and food areas such as drug or active compounds delivery. To conduct production of microparticles, polymeric particle coating, impregnation of active compounds in polymeric films, the knowledge of phase behaviour involving the biodegradable polymer in supercritical carbon dioxide in the presence of a modifier may be needed to allow developing new industrial applications. In this sense, the aim of this work was to investigate the phase behaviour of the ternary system formed by the biodegradable polymer poly(ε-caprolactone) in (carbon dioxide + dichloromethane). Experimental phase transition (bubble and cloud point) values were obtained by applying the static-synthetic method using a variable-volume view cell over the temperature range of (303 to 343) K and pressures up to 21 MPa, in the CO 2 overall composition range of (25-46) wt%, while polymer concentrations studied were (1, 3, 5, and 7) wt%. For the system investigated, depending on the polymer concentration, vapour-liquid, liquid-liquid, and vapour-liquid-liquid phase transitions were verified.

The thermodynamics of direct air capture of carbon dioxide

International Nuclear Information System (INIS)

Lackner, Klaus S.

2013-01-01

An analysis of thermodynamic constraints shows that the low concentration of carbon dioxide in ambient air does not pose stringent limits on air capture economics. The thermodynamic energy requirement is small even using an irreversible sorbent-based process. A comparison to flue gas scrubbing suggests that the additional energy requirement is small and can be supplied with low-cost energy. In general, the free energy expended in the regeneration of a sorbent will exceed the free energy of mixing, as absorption is usually not reversible. The irreversibility, which grows with the depth of scrubbing, tends to affect flue gas scrubbing more than air capture which can successfully operate while extracting only a small fraction of the carbon dioxide available in air. This is reflected in a significantly lower theoretical thermodynamic efficiency for a single stage flue gas scrubber than for an air capture device, but low carbon dioxide concentration in air still results in a larger energy demand for air capture. The energy required for capturing carbon dioxide from air could be delivered in various ways. I analyze a thermal swing and also a previously described moisture swing which is driven by the evaporation of water. While the total amount of heat supplied for sorbent regeneration in a thermal swing, in accordance with Carnot's principle, exceeds the total free energy requirement, the additional free energy required as one moves from flue gas scrubbing to air capture can be paid with an amount of additional low grade heat that equals the additional free energy requirement. Carnot's principle remains satisfied because the entire heat supplied, not just the additional amount, must be delivered at a slightly higher temperature. Whether the system is driven by water evaporation or by low grade heat, the cost of the thermodynamically-required energy can be as small as $1 to $2 per metric ton of carbon dioxide. Thermodynamics does not pose a practical constraint on the

Extended-length fiber optic carbon dioxide monitoring

Science.gov (United States)

Delgado-Alonso, Jesus; Lieberman, Robert A.

2013-05-01

This paper discusses the design and performance of fiber optic distributed intrinsic sensors for dissolved carbon dioxide, based on the use optical fibers fabricated so that their entire lengths are chemically sensitive. These fibers use a polymer-clad, silica-core structure where the cladding undergoes a large, reversible, change in optical absorbance in the presence of CO2. The local "cladding loss" induced by this change is thus a direct indication of the carbon dioxide concentration in any section of the fiber. To create these fibers, have developed a carbon dioxide-permeable polymer material that adheres well to glass, is physically robust, has a refractive index lower than fused silica, and acts as excellent hosts for a unique colorimetric indicator system that respond to CO2. We have used this proprietary material to produce carbon-dioxide sensitive fibers up to 50 meters long, using commercial optical fiber fabrication techniques. The sensors have shown a measurement range of dissolved CO2 of 0 to 1,450 mg/l (0 to 100% CO2 saturation), limit of detection of 0.3 mg/l and precision of 1.0 mg/l in the 0 to 50 mg/l dissolved CO2 range, when a 5 meter-long sensor fiber segment is used. Maximum fiber length, minimum detectable concentration, and spatial resolution can be adjusted by adjusting indicator concentration and fiber design.

Deposition of carbon dioxide

International Nuclear Information System (INIS)

2001-01-01

In Norway, there is currently a debate about whether or not to build gas power stations. To meet the possibility of reduced emission quotas for carbon dioxide in the future, current interest focuses on the incorporation of large-scale separation and deposition of carbon dioxide when such plants are planned. A group of experts concludes that this technology will become self-financing by means of environmental taxes. From the environmental point of view, taxes upon production are to be preferred over taxes on consumption

Ions in carbon dioxide at an atmospheric pressure

International Nuclear Information System (INIS)

Ikezoe, Yasumasa; Onuki, Kaoru; Shimizu, Saburo; Nakajima, Hayato; Sato, Shoichi; Matsuoka, Shingo; Nakamura, Hirone; Tamura, Takaaki

1985-01-01

The formation and the subsequent reactions of positive and negative ions were observed by a time resolved atmospheric pressure ionization mass spectrometer (TRAPI) in an atmospheric pressure carbon dioxide added with small amounts of carbon monoxide and oxygen. A relatively stable ion of (44 x n) + (n >= 2) having a different reactivity from that of (CO 2 ) + sub(n) was found to be one of major ionic species in this gas system. This species was tentatively assigned as [O 2 (CO) 2 ] + (CO 2 )sub(n-2). A new reaction sequence of positive ions is proposed which can be operative in the radiolysis of carbon dioxide at 1 atm. (author)

Research Progress in Carbon Dioxide Storage and Enhanced Oil Recovery

Science.gov (United States)

Wang, Keliang; Wang, Gang; Lu, Chunjing

2018-02-01

With the rapid development of global economy, human beings have become highly dependent upon fossil fuel such as coal and petroleum. Much fossil fuel is consumed in industrial production and human life. As a result, carbon dioxide emissions have been increasing, and the greenhouse effects thereby generated are posing serious threats to environment of the earth. These years, increasing average global temperature, frequent extreme weather events and climatic changes cause material disasters to the world. After scientists’ long-term research, ample evidences have proven that emissions of greenhouse gas like carbon dioxide have brought about tremendous changes to global climate. To really reduce carbon dioxide emissions, governments of different countries and international organizations have invested much money and human resources in performing research related to carbon dioxide emissions. Manual underground carbon dioxide storage and carbon dioxide-enhanced oil recovery are schemes with great potential and prospect for reducing carbon dioxide emissions. Compared with other schemes for reducing carbon dioxide emissions, aforementioned two schemes exhibit high storage capacity and yield considerable economic benefits, so they have become research focuses for reducing carbon dioxide emissions. This paper introduces the research progress in underground carbon dioxide storage and enhanced oil recovery, pointing out the significance and necessity of carbon dioxide-driven enhanced oil recovery.

Social Roots of Global Environmental Change: A World-Systems Analysis of Carbon Dioxide Emissions

Directory of Open Access Journals (Sweden)

J. Timmons Roberts

2015-08-01

Full Text Available Carbon dioxide is understood to be the most important greenhouse gas believed to be altering the global climate. This article applies world-system theory to environmental damage. An analysis of 154 countries examines the contribution of both position in the world economy and internal class and political forces in determining a nation's CO, intensity. CO, intensity is defined here as the amount of carbon dioxide released per unit of economic output. An inverted U distribution of CO, intensity across the range of countries in the global stratification system is identified and discussed. Ordinary Least Squares regression suggests that the least efficient consumers of fossil fuels are some countries within the semi-periphery and upper periphery, spe-cifically those nations which are high exporters, those highly in debt, nations with higher military spending, and those with a repressive social structure.

Residential carbon dioxide emissions in Canada. Impact of efficiency improvements and fuel substitution

International Nuclear Information System (INIS)

Ugursal, V.I.; FUng, A.S.

1998-01-01

The effect of improving house envelope, heating system and appliance efficiencies, and fuel substitution on the atmospheric emissions of carbon dioxide in the Canadian residential sector is studied based on simulation studies. The findings clearly indicate that improving appliance efficiency reduces the overall end-use energy consumption in the residential sector as well as the associated carbon dioxide emissions. However, the magnitude of the reduction in carbon dioxide emissions as a result of improving only appliance efficiencies is quite small. Significantly larger reductions can be obtained by improving house envelopes and heating/cooling systems in addition to improving appliance efficiencies. Fuel substitution for space and domestic hot water heating can also present a potential to reduce carbon dioxide emissions depending on the fuel substitution scenario adopted. (author)

Energy efficient solvent regeneration process for carbon dioxide capture

Science.gov (United States)

Zhou, Shaojun; Meyer, Howard S.; Li, Shiguang

2018-02-27

A process for removing carbon dioxide from a carbon dioxide-loaded solvent uses two stages of flash apparatus. Carbon dioxide is flashed from the solvent at a higher temperature and pressure in the first stage, and a lower temperature and pressure in the second stage, and is fed to a multi-stage compression train for high pressure liquefaction. Because some of the carbon dioxide fed to the compression train is already under pressure, less energy is required to further compress the carbon dioxide to a liquid state, compared to conventional processes.

Active Control of pH in the Bioculture System Through Carbon Dioxide Control

Science.gov (United States)

Monhollon, Luke; Pletcher, David; Hauss, Jessica

2016-01-01

For successful cell research, the growth culture environment must be tightly controlled. Deviance from the optimal conditions will mask the desired variable being analyzed or lead to inconstancies in the results. In standard laboratories, technology and procedures are readily available for the reliable control of variables such as temperature, pH, nutrient loading, and dissolved gases. Due to the nature of spaceflight, and the inherent constraints to engineering designs, these same elements become a challenge to maintain at stable values by both automated and manual approaches. Launch mass, volume, and power usage create significant constraints to cell culture systems; nonetheless, innovative solutions for active environmental controls are available. The acidity of the growth media cannot be measured through standard probes due to the degradation of electrodes and reliance on indicators for chromatography. Alternatively, carbon dioxide sensors are capable of monitoring the pH by leveraging the relationship between the partial pressure of carbon dioxide and carbonic acid in solution across a membrane. In microgravity cell growth systems, the gas delivery system can be used to actively maintain the media at the proper acidity by maintaining a suitable gas mixture around permeable tubing. Through this method, launch mass and volume are significantly reduced through the efficient use of the limited gas supply in orbit.

Carbon Dioxide for pH Control

Energy Technology Data Exchange (ETDEWEB)

Wagonner, R.C.

2001-08-16

Cardox, the major supplier of carbon dioxide, has developed a diffuser to introduce carbon dioxide into a water volume as small bubbles to minimize reagent loss to the atmosphere. This unit is integral to several configurations suggested for treatment to control alkalinity in water streams.

More bad news about carbon dioxide emissions

International Nuclear Information System (INIS)

Stonehouse, D.

2000-01-01

The affect that increased carbon dioxide concentrations has on plants and animals was discussed. Most research focuses on the impacts that carbon dioxide concentrations has on climatic change. Recent studies, however, have shown that elevated levels of carbon dioxide in the atmosphere caused by burning fossils fuels changes the chemical structure of plants and could lead to significant disruptions in ecological food chains. High carbon dioxide levels cause plants to speed up photosynthesis, take in the gas, and use the carbon to produce more fibre and starch while giving off oxygen as a byproduct. As plants produce more carbon, their levels of nitrogen diminish making them less nutritious for the insects and animals that feed on them. This has serious implications for farmers, as pests would have to eat more of their crops to survive. In addition, farmers would have to supplement livestock with nutrients

Method and aparatus for flue gas cleaning by separation and liquefaction of sulfur dioxide and carbon dioxide

International Nuclear Information System (INIS)

Abdelmalek, F.T.

1992-01-01

This patent describes a method for recovering sulfur dioxide, carbon dioxide, and cleaning flue gases emitted from power plants. It comprises: electronically treating the flue gases to neutralize its electrostatic charges and to enhance the coagulation of its molecules and particles; exchanging sensible and latent heat of the neutralized flue gases to lower its temperature down to a temperature approaching the ambient temperature while recovering its separating the flue gas in a first stage; cooling the separated enriched carbon dioxide gas fraction, after each separation stage, while removing its vapor condensate, then compressing the enriched carbon dioxide gas fraction and simultaneously cooling the compressed gas to liquefy the sulfur dioxide gas then; allowing the sulfur dioxide gas to condense, and continuously removing the liquefied sulfur dioxide; compressing he desulfurized enriched carbon dioxide fraction to further increase its pressure, and simultaneously cooling he compressed gas to liquefy the carbon dioxide gas, then; allowing the carbon dioxide gas to condense and continuously removing the liquefied carbon dioxide; allowing the light components of the flue gas to be released in a cooling tower discharge plume

Carbon dioxide capture and storage

International Nuclear Information System (INIS)

Durand, B.

2011-01-01

The author first highlights the reasons why storing carbon dioxide in geological formations could be a solution in the struggle against global warming and climate change. Thus, he comments various evolutions and prospective data about carbon emissions or fossil energy consumption as well as various studies performed by international bodies and agencies which show the interest of carbon dioxide storage. He comments the evolution of CO 2 contributions of different industrial sectors and activities, notably in France. He presents the different storage modes and methods which concern different geological formations (saline aquifers, abandoned oil or gas fields, not exploitable coal seams) and different processes (sorption, carbonation). He discusses the risks associated with these storages, the storable quantities, evokes some existing installations in different countries. He comments different ways to capture carbon dioxide (in post-combustion, through oxy-combustion, by pre-combustion) and briefly evokes some existing installations. He evokes the issue of transport, and discusses efficiency and cost aspects, and finally has few words on legal aspects and social acceptability

Evaluation of Refrigerating and Air Conditioning Devices in Energy Cascade Systems under the Restriction of Carbon Dioxide Emissions

Science.gov (United States)

Shimazaki, Yoichi; Akisawa, Atsushi; Kashiwagi, Takao

It is necessary to introduce energy cascade systems into the industrial sector in Japan to reduce carbon dioxide emissions. The aim of this study is to evaluate the refrigerating and air conditioning devices in cases of introducing both energy cascade systems and thermal recycling systems in industries located around urban areas. The authors have developed an energy cascade model based on linear programming so as to minimize the total system costs with carbon taxes. Five cases are investigated. Limitation of carbon dioxide emissions results in the enhancement of heat cascading, where high temperature heat is supplied for process heating while low temperature one is shifted to refrigeration. It was found that increasing the amount of garbage combustor waste heat can reduce electric power for the turbo refrigerator by promoting waste heat driven ammonia absorption refrigerator.

Optical performance of the Gemini carbon dioxide laser fusion system

International Nuclear Information System (INIS)

Viswanathan, V.K.; Hayden, J.J.; Liberman, I.

1979-01-01

The performance of the Gemini two beam carbon dioxide laser fusion system was recently upgraded by installation of optical components with improved quality in the final amplifier. A theoretical analysis was conducted in conjunction with measurements of the new performance. The analysis and experimental procedures, and results obtained are reported and compared. Good agreement was found which was within the uncertainties of the analysis and the inaccuracies of the experiments. The focal spot Strehl ratio was between 0.24 and 0.3 for both beams

HIGH PRESSURE VAPOR-LIQUID EQUILIBRIA OF PALM FATTY ACIDS DISTILLATES-CARBON DIOXIDE SYSTEM

Directory of Open Access Journals (Sweden)

Nélio T. MACHADO

1997-12-01

Full Text Available Vapor-Liquid equilibria of palm fatty acids distillates/carbon dioxide system has been investigated experimentally at temperatures of 333, 353, and 373 K and pressures of 20, 23, 26, and 29 MPa using the static method. Experimental data for the quasi-binary system palm fatty acids distillates/carbon dioxide has been correlated with Redlich-Kwong-Aspen equation of state. Modeling shows good agreement with experimental data. Selectivity obtained indicates that supercritical carbon dioxide is a reasonable solvent for separating saturated (palmitic acid and unsaturated (oleic+linoleic acids fatty acids from palm fatty acids distillates in a continuous multistage countercurrent column.Foi investigado experimentalmente o equilíbrio líquido-vapor para o sistema Destilado Ácido de Óleo de Palma (PFAD/Dióxido de Carbono, nas temperaturas de 333, 353 e 373 K e pressões de 20, 23, 26 e 29 MPa, usando-se o método estático. Os dados experimentais do sistema pseudo-binário PFAD/CO2 foram correlacionados com a equação de estado de Redlich-Kwong do pacote computacional ASPEN. O modelo reproduz bem os resultados experimentais. A seletividade obtida indica que o CO2 supercrítico é um solvente razoável para a separação em coluna multi-estágio e contínua, do ácido graxo saturado (ácido palmítico daqueles insaturados (ácido oleico e ácido linoleico contidos no PFAD.

Difficult colonoscopy: air, carbon dioxide, or water insufflation?

Science.gov (United States)

Chaubal, Alisha; Pandey, Vikas; Patel, Ruchir; Poddar, Prateik; Phadke, Aniruddha; Ingle, Meghraj; Sawant, Prabha

2018-04-01

This study aimed to compare tolerance to air, carbon dioxide, or water insufflation in patients with anticipated difficult colonoscopy (young, thin, obese individuals, and patients with prior abdominal surgery or irradiation). Patients with body mass index (BMI) less than 18 kg/m 2 or more than 30 kg/m 2 , or who had undergone previous abdominal or pelvic surgeries were randomized to air, carbon dioxide, or water insufflation during colonoscopy. The primary endpoint was cecal intubation with mild pain (less than 5 on visual analogue scale [VAS]), without use of sedation. The primary end point was achieved in 32.7%, 43.8%, and 84.9% of cases with air, carbon dioxide and water insufflation ( P carbon dioxide, and water insufflation ( P carbon dioxide for pain tolerance. This was seen in the subgroups with BMI 30 kg/m 2 .

Method for carbon dioxide sequestration

Science.gov (United States)

Wang, Yifeng; Bryan, Charles R.; Dewers, Thomas; Heath, Jason E.

2017-12-05

A method for geo-sequestration of a carbon dioxide includes selection of a target water-laden geological formation with low-permeability interbeds, providing an injection well into the formation and injecting supercritical carbon dioxide (SC-CO.sub.2) and water or bine into the injection well under conditions of temperature, pressure and density selected to cause the fluid to enter the formation and splinter and/or form immobilized ganglia within the formation.

Carbon Dioxide Effects Research and Assessment Program: Proceedings of the carbon dioxide and climate research program conference

Energy Technology Data Exchange (ETDEWEB)

Schmitt, L E [ed.

1980-12-01

Papers presented at the Carbon Dioxide and Climate Research Program Conference are included in this volume. Topics discussed are: the carbon cycle; modeling the carbon system; climatic response due to increased CO₂; climate modeling; the use of paleoclimatic data in understanding climate change; attitudes and implications of CO₂; social responses to the CO₂ problem; a scenario for atmospheric CO₂ to 2025; marine photosynthesis and the global carbon cycle; and the role of tropical forests in the carbon balance of the world. Separate abstracts of nine papers have been prepared for inclusion in the Energy Data Base. (RJC)

Amperometric sensor for carbon dioxide: design, characteristics, and perforance

International Nuclear Information System (INIS)

Evans, J.; Pletcher, D.; Warburton, P.R.G.; Gibbs, T.K.

1989-01-01

A new sensor for atmospheric carbon dioxide is described. It is an amperometric device based on a porous electrode in a three-electrode cell and the electrolyte is a copper diamine complex in aqueous potassium chloride. The platinum cathode, held at constant potential, is used to detect the formation of Cu 2+ following the change in the pH of the solution when the sensor is exposed to an atmosphere containing carbon dioxide. The sensor described is designed to monitor carbon dioxide concentrations in the range 0-5%, although with some modifications, other ranges would be possible. The response to a change in the carbon dioxide content of the atmosphere is rapid (about 10s) while the monitored current is strongly (but nonlinearly) dependent on carbon dioxide concentration. Unlike other amperometric devices for carbon dioxide, there is no interference from oxygen although other acid gases would lead to an interfering response

Effect of Elevated Carbon Dioxide Concentration on Carbon Assimilation under Fluctuating Light

Czech Academy of Sciences Publication Activity Database

Holišová, Petra; Zitová, Martina; Klem, Karel; Urban, Otmar

2012-01-01

Roč. 41, č. 6 (2012), s. 1931-1938 ISSN 0047-2425 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073; GA ČR(CZ) GAP501/10/0340; GA MŠk(CZ) LM2010007; GA AV ČR IAA600870701 Institutional support: RVO:67179843 Keywords : carbon * light * beech * spruce * carbon assimilation * elevat e carbon * dioxide concentration * mol * photosynthetic * assimilation * carbon dioxide * dioxide * concentracion * leave * photosynthetic efficiency Subject RIV: EH - Ecology, Behaviour Impact factor: 2.353, year: 2012

Carbon dioxide from fossil fuels: adapting to uncertainty

Energy Technology Data Exchange (ETDEWEB)

Chen, K; Winter, R C; Bergman, M K

1980-12-01

If present scientific information is reasonable, the world is likely to experience noticeable global warming by the beginning of the next century if high annual growth rates of fossil-fuel energy use continue. Only with optimistic assumptions and low growth rates will carbon-dioxide-induced temperature increases be held below 2/sup 0/C or so over the next century. Conservation, flexible energy choices, and control options could lessen the potential effects of carbon dioxide. Though perhaps impractical from the standpoint of costs and efficiency losses, large coastal centralized facilities would be the most amenable to carbon dioxide control and disposal. Yet no country can control carbon dioxide levels unilaterally. The USA, however, which currently contributes over a quarter of all fossil-fuel carbon dioxide emissions and possesses a quarter of the world's coal resources, could provide a much needed role in leadership, research and education. 70 references.

Carbon dioxide for enhanced oil recovery in Canada

Energy Technology Data Exchange (ETDEWEB)

McDonald, S.; Manbybura, F.; Sparks, N.

1985-01-01

This paper examines the potential for carbon dioxide as a major miscible solvent in Canada and describes Shell Canada's carbon dioxide exploration efforts over the last few years. Enhanced oil recovery, specifically miscible flooding, has been recognized as a technically and economically feasible method for adding reserves and productive capacity to Canada's light and medium oil. The fiscal regime has been altered by both the federal and provincial governments to encourage miscible flooding development. As a result many projects have been initiated with others being evaluated and designed. This paper analyzes the history and the direction of miscible flooding in the United States, where carbon dioxide is becoming the predominant miscible solvent. The potential for future use of carbon dioxide in Canada is specifically addressed: potential oil recovery solvent supply, and economics. Shell's carbon dioxide exploration play currently underway is also discussed.

New technology for carbon dioxide at high pressure

International Nuclear Information System (INIS)

Hassina, Bazaze; Raouf, Zehioua; Menial, A. H.

2006-01-01

Carbon dioxide has long been the nemesis of environmentalists because of its role in global warming, but under just the right conditions-namely, high pressure and high temperature its one of nature's best and most environmentally benign solvents. Decaf-coffee lovers, for instance, benefit from its ability to remove caffeine from coffee beans.During the last few years, carbon dioxide has also made inroads in the dry-cleaning industry, providing a safe cleaning alternative to the chemical perchloroethylene. But it's on the high-tech front that carbon dioxide may make its biggest impact. T here are huge opportunities. Scientists have known for more than a century that at 75 times atmospheric pressure and 31 degree centigrade, carbon dioxide goes into and odd state that chemists called s upercritical . What's interesting to industry is that supercritical carbon dioxide may be an enabling technology for going to smaller dimensions.(Author)

Biological fixation of carbon dioxide. Seibutsu ni yoru nisanka tanso no kotei

Energy Technology Data Exchange (ETDEWEB)

Someya, J [Fermentaion Research Institute, Tsukuba (Japan)

1991-10-20

Bulks of photosynthetic product to reduce the carbon dioxide by the light energy are forests, represented by the tropical rain forests, on the land, and marine algae and coral reefs in the ocean. For the purpose of effectively utilizing the fixation power of carbon dioxide through the photosynthesis by higher plants and algae, it is necessary to make many further researches, starting with a conditional selection of species, excellent in both absorption and fixation of carbon dioxide. The Japan Technology Transfer Association has recently issued a design to build a large scale closed type farm in the vicinity of factory, exhausting the carbon dioxide, and supply it to structure a system of producing vegetable and other food. What largely contributes to the calcification in the ocean is the coral reefs, where coral is symbiotic with brown algae., called dinoflagellatae. Those algae are judged to accelerate the formation of calcium carbonate by the photosynthesis. To estimate the absorption power of oceanic carbon dioxide, it is important to quantitatively know the calcification by the coral. 4 figs., 1 tab.

Selective free radical reactions using supercritical carbon dioxide.

Science.gov (United States)

Cormier, Philip J; Clarke, Ryan M; McFadden, Ryan M L; Ghandi, Khashayar

2014-02-12

We report herein a means to modify the reactivity of alkenes, and particularly to modify their selectivity toward reactions with nonpolar reactants (e.g., nonpolar free radicals) in supercritical carbon dioxide near the critical point. Rate constants for free radical addition of the light hydrogen isotope muonium to ethylene, vinylidene fluoride, and vinylidene chloride in supercritical carbon dioxide are compared over a range of pressures and temperatures. Near carbon dioxide's critical point, the addition to ethylene exhibits critical speeding up, while the halogenated analogues display critical slowing. This suggests that supercritical carbon dioxide as a solvent may be used to tune alkene chemistry in near-critical conditions.

Trading coalbed methane for carbon dioxide

International Nuclear Information System (INIS)

Greenberger, L.S.

1991-01-01

This article discusses a proposal for reducing methane emissions in coal mining activities and at the same time reducing the burden on utilities to cut carbon dioxide emissions. Emission credits would be issued to mines that recover the methane for use. These credits could then be bought by utilities and exchanged for the right to emit carbon dioxide

Synthesis of Chiral Cyclic Carbonates via Kinetic Resolution of Racemic Epoxides and Carbon Dioxide

Directory of Open Access Journals (Sweden)

Xiao Wu

2016-01-01

Full Text Available The catalytic synthesis of cyclic carbonates using carbon dioxide as a C1-building block is a highly active area of research. Here, we review the catalytic production of enantiomerically enriched cyclic carbonates via kinetic resolution of racemic epoxides catalysed by metal-containing catalyst systems.

Liquid carbon dioxide absorbents, methods of using the same, and related system

Science.gov (United States)

Perry, Robert James; Soloveichik, Grigorii Lev; Rubinsztajn, Malgorzata Iwona; O'Brien, Michael Joseph; Lewis, Larry Neil; Lam, Tunchiao Hubert; Kniajanski, Sergei; Hancu, Dan

2018-05-01

A carbon dioxide absorbent composition is described, including (i) a liquid, nonaqueous silicon-based material, functionalized with one or more groups that either reversibly react with CO2 or have a high-affinity for CO2, and (ii) a hydroxy-containing solvent that is capable of dissolving both the silicon-based material and a reaction product of the silicon-based material and CO2. The absorbent may be utilized in methods to reduce carbon dioxide in an exhaust gas, and finds particular utility in power plants.

Production of precipitated calcium carbonate from calcium silicates and carbon dioxide

International Nuclear Information System (INIS)

Teir, Sebastian; Eloneva, Sanni; Zevenhoven, Ron

2005-01-01

The possibilities for reducing carbon dioxide emissions from the pulp and paper industry by calcium carbonation are presented. The current precipitated calcium carbonate (PCC) production uses mined, crushed calcium carbonate as raw materials. If calcium silicates were used instead, carbon dioxide emissions from the calcination of carbonates would be eliminated. In Finland, there could, thus, be a potential for eliminating 200 kt of carbon dioxide emissions per year, considering only the PCC used in the pulp and paper industry. A preliminary investigation of the feasibility to produce PCC from calcium silicates and the potential to replace calcium carbonate as the raw material was made. Calcium carbonate can be manufactured from calcium silicates by various methods, but only a few have been experimentally verified. The possibility and feasibility of these methods as a replacement for the current PCC production process was studied by thermodynamic equilibrium calculations using HSC software and process modelling using Aspen Plus[reg]. The results from the process modelling showed that a process that uses acetic acid for extraction of the calcium ions is a high potential option for sequestering carbon dioxide by mineral carbonation. The main obstacle seems to be the limited availability and relatively high price of wollastonite, which is a mineral with high calcium silicate content. An alternative is to use the more common, but also more complex, basalt rock instead

Carbon dioxide absorbent and method of using the same

Science.gov (United States)

Perry, Robert James [Niskayuna, NY; Lewis, Larry Neil [Scotia, NY; O'Brien, Michael Joseph [Clifton Park, NY; Soloveichik, Grigorii Lev [Latham, NY; Kniajanski, Sergei [Clifton Park, NY; Lam, Tunchiao Hubert [Clifton Park, NY; Lee, Julia Lam [Niskayuna, NY; Rubinsztajn, Malgorzata Iwona [Ballston Spa, NY

2011-10-04

In accordance with one aspect, the present invention provides an amino-siloxane composition comprising at least one of structures I, II, III, IV or V said compositions being useful for the capture of carbon dioxide from gas streams such as power plant flue gases. In addition, the present invention provides methods of preparing the amino-siloxane compositions are provided. Also provided are methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention as species which react with carbon dioxide to form an adduct with carbon dioxide. The reaction of the amino-siloxane compositions provided by the present invention with carbon dioxide is reversible and thus, the method provides for multicycle use of said compositions.

Carbon dioxide hydrate formation in a fixed-bed reactor

Energy Technology Data Exchange (ETDEWEB)

Fan, S.; Lang, X. [South China Univ. of Technology, Guangzhou (China). Key Laboratory of Enhanced Heat Transfer and Energy Conservation; Wang, Y.; Liang, D. [Chinese Academy of Sciences, Guangzhou (China). Guangzhou Inst. of Energy Conversion and Guangzhou Center of Natural Gas Hydrate; Sun, X.; Jurcik, B. [Air Liquide Laboratories, Tsukuba (Japan)

2008-07-01

Gas hydrates are thermodynamically stable at high pressures and near the freezing temperature of pure water. Methane hydrates occur naturally in sediments in the deep oceans and permafrost regions and constitute an extensive hydrocarbon reservoir. Carbon dioxide (CO{sub 2}) hydrates are of interest as a medium for marine sequestration of anthropogenic carbon dioxide. Sequestering CO{sub 2} as hydrate has potential advantages over most methods proposed for marine CO{sub 2} sequestration. Because this technique requires a shallower depth of injection when compared with other ocean sequestration methods, the costs of CO{sub 2} hydrate sequestration may be lower. Many studies have successfully used different continuous reactor designs to produce CO{sub 2} hydrates in both laboratory and field settings. This paper discussed a study that involved the design and construction of a fixed-bed reactor for simulation of hydrate formation system. Water, river sands and carbon dioxide were used to simulate the seep kind of hydrate formation. Carbon dioxide gas was distributed as small bubbles to enter from the bottom of the fixed-bed reactor. The paper discussed the experimental data and presented a diagram of the gas hydrate reactor system. The morphology as well as the reaction characters of CO{sub 2} hydrate was presented in detail. The results were discussed in terms of experimental phenomena and hydrate formation rate. A mathematical model was proposed for describing the process. 17 refs., 7 figs.

A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

Science.gov (United States)

Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, Chandrasekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

2016-12-01

Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts.

A metal-free electrocatalyst for carbon dioxide reduction to multi-carbon hydrocarbons and oxygenates

Science.gov (United States)

Wu, Jingjie; Ma, Sichao; Sun, Jing; Gold, Jake I.; Tiwary, ChandraSekhar; Kim, Byoungsu; Zhu, Lingyang; Chopra, Nitin; Odeh, Ihab N.; Vajtai, Robert; Yu, Aaron Z.; Luo, Raymond; Lou, Jun; Ding, Guqiao; Kenis, Paul J. A.; Ajayan, Pulickel M.

2016-01-01

Electroreduction of carbon dioxide into higher-energy liquid fuels and chemicals is a promising but challenging renewable energy conversion technology. Among the electrocatalysts screened so far for carbon dioxide reduction, which includes metals, alloys, organometallics, layered materials and carbon nanostructures, only copper exhibits selectivity towards formation of hydrocarbons and multi-carbon oxygenates at fairly high efficiencies, whereas most others favour production of carbon monoxide or formate. Here we report that nanometre-size N-doped graphene quantum dots (NGQDs) catalyse the electrochemical reduction of carbon dioxide into multi-carbon hydrocarbons and oxygenates at high Faradaic efficiencies, high current densities and low overpotentials. The NGQDs show a high total Faradaic efficiency of carbon dioxide reduction of up to 90%, with selectivity for ethylene and ethanol conversions reaching 45%. The C2 and C3 product distribution and production rate for NGQD-catalysed carbon dioxide reduction is comparable to those obtained with copper nanoparticle-based electrocatalysts. PMID:27958290

Practical modeling approaches for geological storage of carbon dioxide.

Science.gov (United States)

Celia, Michael A; Nordbotten, Jan M

2009-01-01

The relentless increase of anthropogenic carbon dioxide emissions and the associated concerns about climate change have motivated new ideas about carbon-constrained energy production. One technological approach to control carbon dioxide emissions is carbon capture and storage, or CCS. The underlying idea of CCS is to capture the carbon before it emitted to the atmosphere and store it somewhere other than the atmosphere. Currently, the most attractive option for large-scale storage is in deep geological formations, including deep saline aquifers. Many physical and chemical processes can affect the fate of the injected CO2, with the overall mathematical description of the complete system becoming very complex. Our approach to the problem has been to reduce complexity as much as possible, so that we can focus on the few truly important questions about the injected CO2, most of which involve leakage out of the injection formation. Toward this end, we have established a set of simplifying assumptions that allow us to derive simplified models, which can be solved numerically or, for the most simplified cases, analytically. These simplified models allow calculation of solutions to large-scale injection and leakage problems in ways that traditional multicomponent multiphase simulators cannot. Such simplified models provide important tools for system analysis, screening calculations, and overall risk-assessment calculations. We believe this is a practical and important approach to model geological storage of carbon dioxide. It also serves as an example of how complex systems can be simplified while retaining the essential physics of the problem.

Phase composition and saturated liquid properties in binary and ternary systems containing carbon dioxide, n-decane, and n-tetradecane

International Nuclear Information System (INIS)

Kariznovi, Mohammad; Nourozieh, Hossein; Abedi, Jalal

2013-01-01

Highlights: ► Binary and ternary systems of (carbon dioxide + n-decane + n-tetradecane) at 323.2 K. ► Isothermal phase properties measurements over wide range of pressure (1 to 6) MPa. ► Experimental measurements, density, viscosity, and composition, using a designed PVT apparatus. ► The experimental data were correlated using two equations of state. ► The interaction parameters and the volume shift values from the experimental data on the binary pairs. - Abstract: Experimental phase equilibrium data have been measured for the binary and ternary systems containing (carbon dioxide, n-decane, and n-tetradecane) at 323.2 K over the pressure range (1 to 6) MPa using a designed PVT apparatus. The measurements presented in this paper were undertaken to determine liquid phase composition and liquid saturated properties (density and viscosity) when a liquid hydrocarbon (n-decane, n-tetradecane, and their mixtures) was saturated with carbon dioxide. The generated data for compositions and densities were correlated with the Soave–Redlich–Kwong (SRK) and Peng–Robinson (PR) equations of state (EOS). The adjustment of binary interaction parameters and volume translation technique has been employed to correlate the experimental compositions and densities. The adjusted binary parameters from the data of binary pairs (carbon dioxide + n-decane) and (carbon dioxide + n-tetradecane) were used to correlate the generated ternary data. The calculated ternary compositions were found to be in good agreement with the experimental data using the binary parameters from the data of binary pairs for both EOSs. The results for the density of saturated liquid phase indicated that the volume translation should be applied to all components in the binary and ternary systems to describe accurately the saturated liquid densities for mixtures.

Reaction of yttrium polonides with carbon dioxide

International Nuclear Information System (INIS)

Abakumov, A.S.; Khokhlov, A.D.; Reznikova, N.F.

1986-01-01

It has been proved that heating of yttrium and tantalum in carbon dioxide to 500 and 800 0 C alters the gas phase composition, causing formation of carbon monoxide and reduction of oxygen content. A study of the thermal stability of yttrium polonides in carbon dioxide showed that yttrium sesqui- and monopolonides decompose at 400-430 0 C. The temperature dependence of the vapor pressure of polonium obtained upon decomposition of the referred polonides has been determined in a carbon dioxide environment radiotensometrically. The enthalpy of the process calculated from this dependence is close to the enthalpy of vaporization of elemental polonium in vacuo. The mechanism of the reactions has been suggested

Reaction of titanium polonides with carbon dioxide

International Nuclear Information System (INIS)

Abakumov, A.S.; Malyshev, M.L.; Reznikova, N.F.

1987-01-01

It has been ascertained that heating titanium and tantalum in carbon dioxide to temperatures of 500 or 800 0 C alters the composition of the gas phase, causing the advent of carbon monoxide and lowering the oxygen content. Investigation of the thermal stability of titanium polonides in a carbon dioxide medium has shown that titanium mono- and hemipolonides are decomposed at temperatures below 350 0 C. The temperature dependence of the vapor pressure of polonium produced in the decomposition of these polonides in a carbon dioxide medium have been determined by a radiotensimetric method. The enthalpy of the process, calculated from this relationship, is close to the enthalpy of vaporization of elementary polonium in vacuo

Liquid carbon dioxide absorbents, methods of using the same, and related systems

Energy Technology Data Exchange (ETDEWEB)

O' Brien, Michael Joseph; Perry, Robert James; Lam, Tunchiao Hubert; Soloveichik, Grigorii Lev; Kniajanski, Sergei; Lewis, Larry Neil; Rubinsztajn, Malgorzata Iwona; Hancu, Dan

2016-09-13

A carbon dioxide absorbent composition is described, including (i) a liquid, nonaqueous silicon-based material, functionalized with one or more groups that either reversibly react with CO.sub.2 or have a high-affinity for CO.sub.2; and (ii) a hydroxy-containing solvent that is capable of dissolving both the silicon-based material and a reaction product of the silicon-based material and CO.sub.2. The absorbent may be utilized in methods to reduce carbon dioxide in an exhaust gas, and finds particular utility in power plants.

Carbon dioxide absorbent and method of using the same

Science.gov (United States)

Perry, Robert James; O'Brien, Michael Joseph

2014-06-10

In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbon dioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbon dioxide to form an adduct with carbon dioxide.

Carbon dioxide absorbent and method of using the same

Energy Technology Data Exchange (ETDEWEB)

Perry, Robert James; O' Brien, Michael Joseph

2015-12-29

In accordance with one aspect, the present invention provides a composition which contains the amino-siloxane structures I, or III, as described herein. The composition is useful for the capture of carbon dioxide from process streams. In addition, the present invention provides methods of preparing the amino-siloxane composition. Another aspect of the present invention provides methods for reducing the amount of carbon dioxide in a process stream employing the amino-siloxane compositions of the invention, as species which react with carbon dioxide to form an adduct with carbon dioxide.

Direct phase coexistence molecular dynamics study of the phase equilibria of the ternary methane-carbon dioxide-water hydrate system.

Science.gov (United States)

Michalis, Vasileios K; Tsimpanogiannis, Ioannis N; Stubos, Athanassios K; Economou, Ioannis G

2016-09-14

Molecular dynamics simulation is used to predict the phase equilibrium conditions of a ternary hydrate system. In particular, the direct phase coexistence methodology is implemented for the determination of the three-phase coexistence temperature of the methane-carbon dioxide-water hydrate system at elevated pressures. The TIP4P/ice, TraPPE-UA and OPLS-UA forcefields for water, carbon dioxide and methane respectively are used, in line with our previous studies of the phase equilibria of the corresponding binary hydrate systems. The solubility in the aqueous phase of the guest molecules of the respective binary and ternary systems is examined under hydrate-forming conditions, providing insight into the predictive capability of the methodology as well as the combination of these forcefields to accurately describe the phase behavior of the ternary system. The three-phase coexistence temperature is calculated at 400, 1000 and 2000 bar for two compositions of the methane-carbon dioxide mixture. The predicted values are compared with available calculations with satisfactory agreement. An estimation is also provided for the fraction of the guest molecules in the mixed hydrate phase under the conditions examined.

27 CFR 26.222 - Still wines containing carbon dioxide.

Science.gov (United States)

2010-04-01

... carbon dioxide. 26.222 Section 26.222 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... ISLANDS Formulas for Products From the Virgin Islands § 26.222 Still wines containing carbon dioxide. (a) General. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine...

27 CFR 26.52 - Still wines containing carbon dioxide.

Science.gov (United States)

2010-04-01

... carbon dioxide. 26.52 Section 26.52 Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... ISLANDS Formulas for Products From Puerto Rico § 26.52 Still wines containing carbon dioxide. (a) General. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except...

Monitoring carbon dioxide in mechanically ventilated patients during hyperbaric treatment

DEFF Research Database (Denmark)

Bjerregård, Asger; Jansen, Erik

2012-01-01

Measurement of the arterial carbon dioxide (P(a)CO(2)) is an established part of the monitoring of mechanically ventilated patients. Other ways to get information about carbon dioxide in the patient are measurement of end-tidal carbon dioxide (P(ET)CO(2)) and transcutaneous carbon dioxide (PTCCO2......). Carbon dioxide in the blood and cerebral tissue has great influence on vasoactivity and thereby blood volume of the brain. We have found no studies on the correlation between P(ET)CO(2) or P(TC)CO(2), and P(a)CO(2) during hyperbaric oxygen therapy (HBOT)....

Communication: Photoinduced carbon dioxide binding with surface-functionalized silicon quantum dots

Science.gov (United States)

Douglas-Gallardo, Oscar A.; Sánchez, Cristián Gabriel; Vöhringer-Martinez, Esteban

2018-04-01

Nowadays, the search for efficient methods able to reduce the high atmospheric carbon dioxide concentration has turned into a very dynamic research area. Several environmental problems have been closely associated with the high atmospheric level of this greenhouse gas. Here, a novel system based on the use of surface-functionalized silicon quantum dots (sf-SiQDs) is theoretically proposed as a versatile device to bind carbon dioxide. Within this approach, carbon dioxide trapping is modulated by a photoinduced charge redistribution between the capping molecule and the silicon quantum dots (SiQDs). The chemical and electronic properties of the proposed SiQDs have been studied with a Density Functional Theory and Density Functional Tight-Binding (DFTB) approach along with a time-dependent model based on the DFTB framework. To the best of our knowledge, this is the first report that proposes and explores the potential application of a versatile and friendly device based on the use of sf-SiQDs for photochemically activated carbon dioxide fixation.

Metabolic effects of Carbon Dioxide (CO 2 ) insufflation during ...

African Journals Online (AJOL)

Metabolic effects of Carbon Dioxide (CO 2 ) insufflation during laparoscopic surgery: changes in pH, arterial partial Pressure of Carbon Dioxide (PaCo 2 ) and End Tidal Carbon Dioxide (EtCO 2 ) ... Respiratory adjustments were done for EtCO2 levels above 60mmHg or SPO2 below 92% or adverse haemodynamic changes.

On reaction of titanium polonides with carbon dioxide

International Nuclear Information System (INIS)

Abakumov, A.S.; Malyshev, M.L.; Reznikova, N.F.

1986-01-01

The reaction between titanium polonides and carbon dioxide has been studied by comparing titanium polonide thermal resistance in vacuum and in carbon dioxide. The investigation has shown that titanium mono- and semipolonides fail at temperatures below 350 deg C. Temperature dependence of polonium vapor pressure prepared at failure of the given polonides is determined by the radiotensiometry in carbon dioxide. Enthalpy calculated for this dependence is close to the enthalpy of elementary polonium evaporation in vacuum

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.

The causal nexus between carbon dioxide emissions and agricultural ecosystem-an econometric approach.

Science.gov (United States)

Asumadu-Sarkodie, Samuel; Owusu, Phebe Asantewaa

2017-01-01

Achieving a long-term food security and preventing hunger include a better nutrition through sustainable systems of production, distribution, and consumption. Nonetheless, the quest for an alternative to increasing global food supply to meet the growing demand has led to the use of poor agricultural practices that promote climate change. Given the contribution of the agricultural ecosystem towards greenhouse gas (GHG) emissions, this study investigated the causal nexus between carbon dioxide emissions and agricultural ecosystem by employing a data spanning from 1961 to 2012. Evidence from long-run elasticity shows that a 1 % increase in the area of rice paddy harvested will increase carbon dioxide emissions by 1.49 %, a 1 % increase in biomass-burned crop residues will increase carbon dioxide emissions by 1.00 %, a 1 % increase in cereal production will increase carbon dioxide emissions by 1.38 %, and a 1 % increase in agricultural machinery will decrease carbon dioxide emissions by 0.09 % in the long run. There was a bidirectional causality between carbon dioxide emissions, cereal production, and biomass-burned crop residues. The Granger causality shows that the agricultural ecosystem in Ghana is sensitive to climate change vulnerability.

Phase Equilibria Measurement of Binary Mixture for the Propoxylated Neopentyl Glycol Diacrylate in Supercritical Carbon Dioxide

International Nuclear Information System (INIS)

Byun, Hun-Soo

2016-01-01

Experimental data are reported on the phase equilibrium of propoxylated neopentyl glycol diacrylate in supercritical carbon dioxide. Phase equilibria data were measured in static method at a temperature of (313.2, 333.2, 353.2, 373.2 and 393.2) K and at pressures up to 27.82 MPa. At a constant pressure, the solubility of propoxylated neopentyl glycol diacrylate for the (carbon dioxide + propoxylated neopentyl glycol diacrylate) system increases as temperature increases. The (carbon dioxide + propoxylated neopentyl glycol diacrylate) system exhibits type-I phase behavior. The experimental result for the (carbon dioxide + propoxylated neopentyl glycol diacrylate) system is correlated with Peng- Robinson equation of state using mixing rule. The critical property of propoxylated neopentyl glycol diacrylate is predicted with Joback and Lyderson method

Phase Equilibria Measurement of Binary Mixture for the Propoxylated Neopentyl Glycol Diacrylate in Supercritical Carbon Dioxide

Energy Technology Data Exchange (ETDEWEB)

Byun, Hun-Soo [Chonnam National University, Yeosu (Korea, Republic of)

2016-04-15

Experimental data are reported on the phase equilibrium of propoxylated neopentyl glycol diacrylate in supercritical carbon dioxide. Phase equilibria data were measured in static method at a temperature of (313.2, 333.2, 353.2, 373.2 and 393.2) K and at pressures up to 27.82 MPa. At a constant pressure, the solubility of propoxylated neopentyl glycol diacrylate for the (carbon dioxide + propoxylated neopentyl glycol diacrylate) system increases as temperature increases. The (carbon dioxide + propoxylated neopentyl glycol diacrylate) system exhibits type-I phase behavior. The experimental result for the (carbon dioxide + propoxylated neopentyl glycol diacrylate) system is correlated with Peng- Robinson equation of state using mixing rule. The critical property of propoxylated neopentyl glycol diacrylate is predicted with Joback and Lyderson method.

Carbon dioxide reduction in a tubular solid oxide electrolysis cell for a carbon recycling energy system

Energy Technology Data Exchange (ETDEWEB)

Dipu, Arnoldus Lambertus, E-mail: dipu.a.aa@m.titech.ac.jp [Department of Nuclear Engineering, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8550 (Japan); Ujisawa, Yutaka [Nippon Steel and Sumitomo Metal Corporation, 16-1, Sunayama, Kamisu, Ibaraki 314-0255 (Japan); Ryu, Junichi; Kato, Yukitaka [Research Laboratory for Nuclear Reactors, Tokyo Institute of Technology, 2-12-1-N1-22, Ookayama, Meguro-ku, Tokyo 152-8550 (Japan)

2014-05-01

A new energy transformation system based on carbon recycling is proposed called the active carbon recycling energy system (ACRES). A high-temperature gas reactor was used as the main energy source for ACRES. An experimental study based on the ACRES concept of carbon monoxide (CO) regeneration via high-temperature reduction of carbon dioxide (CO{sub 2}) was carried out using a tubular solid oxide electrolysis cell employing Ni-LSM cermet|YSZ|YSZ-LSM as the cathode|electrolyte|anode. The current density increased with increasing CO{sub 2} concentration at the cathode, which was attributed to a decrease in cathode activation and concentration overpotential. Current density, as well as the CO and oxygen (O{sub 2}) production rates, increased with increasing operating temperature. The highest CO and O{sub 2} production rates of 1.24 and 0.64 μmol/min cm{sup 2}, respectively, were measured at 900 °C. Based on the electrolytic characteristics of the cell, the scale of a combined ACRES CO{sub 2} electrolysis/iron production facility was estimated.

Effects of carbon dioxide on Penicillium chrysogenum: an autoradiographic study

International Nuclear Information System (INIS)

Edwards, A.G.; Ho, C.S.

1988-01-01

Previous research has shown that dissolved carbon dioxide causes significant changes in submerged penicillin fermentations, such as stunted, swollen hyphae, increased branching, lower growth rates, and lower penicillin productivity. Influent carbon dioxide levels of 5 and 10% were shown through the use of autoradiography to cause an increase in chitin synthesis in submerged cultures of Penicillium chrysogenum. At an influent 5% carbon dioxide level, chitin synthesis is ca. 100% greater in the subapical region of P. chrysogenum hyphae than that of the control, in which there was no influent carbon dioxide. Influent carbon dioxide of 10% caused an increase of 200% in chitin synthesis. It is believed that the cell wall must be plasticized before branching can occur and that high amounts of dissolved carbon dioxide cause the cell to lose control of the plasticizing effect, thus the severe morphological changes occur

The formation of ethane from carbon dioxide under cold plasma

International Nuclear Information System (INIS)

Zhang Xiuling; Zhang Lin; Dai Bin; Gong Weimin; Liu Changhou

2001-01-01

Pulsed-corona plasma has been used as a new method for ethane dehydrogenation at low temperature and normal pressure using carbon dioxide as an oxidant. The effect of carbon dioxide content in the feed, power input, and flow rate of the reactants on the ethane dehydrogenation has been investigated. The experimental results show that the conversion of ethane increases with the increasing in the amount of carbon dioxide in the feed. The yield of ethylene and acetylene decreases with the increasing in the yield of carbon monoxide, indicating that the increased carbon dioxide leads to the part of ethylene and acetylene being oxidized to carbon monoxide. Power input is primarily an electrical parameter in pulsed-corona plasma, which plays an important role in reactant conversion and product formation. When the power input reaches 16 W, ethane conversion is 41.0% and carbon dioxide conversion is 26.3%. The total yield of ethylene and acetylene is 15.6%. The reduced flow rate of feed improves the conversion of ethane, carbon dioxide and the yield of acetylene, and induces carbon deposit as well

Changes in plasma potassium concentration during carbon dioxide pneumoperitoneum

DEFF Research Database (Denmark)

Perner, A; Bugge, K; Lyng, K M

1999-01-01

Hyperkalaemia with ECG changes had been noted during prolonged carbon dioxide pneumoperitoneum in pigs. We have compared plasma potassium concentrations during surgery in 11 patients allocated randomly to undergo either laparoscopic or open appendectomy and in another 17 patients allocated randomly...... to either carbon dioxide pneumoperitoneum or abdominal wall lifting for laparoscopic colectomy. Despite an increasing metabolic acidosis, prolonged carbon dioxide pneumoperitoneum resulted in only a slight increase in plasma potassium concentrations, which was both statistically and clinically insignificant....... Thus hyperkalaemia is unlikely to develop in patients with normal renal function undergoing carbon dioxide pneumoperitoneum for laparoscopic surgery....

Carbon dioxide elimination and regeneration of resources in a microwave plasma torch

International Nuclear Information System (INIS)

Uhm, Han S.; Kwak, Hyoung S.; Hong, Yong C.

2016-01-01

Carbon dioxide gas as a working gas produces a stable plasma-torch by making use of 2.45 GHz microwaves. The temperature of the torch flame is measured by making use of optical spectroscopy and a thermocouple device. Two distinctive regions are exhibited, a bright, whitish region of a high-temperature zone and a bluish, dimmer region of a relatively low-temperature zone. The bright, whitish region is a typical torch based on plasma species where an analytical investigation indicates dissociation of a substantial fraction of carbon dioxide molecules, forming carbon monoxides and oxygen atoms. The emission profiles of the oxygen atoms and the carbon monoxide molecules confirm the theoretical predictions of carbon dioxide disintegration in the torch. Various hydrocarbon materials may be introduced into the carbon dioxide torch, regenerating new resources and reducing carbon dioxide concentration in the torch. As an example, coal powders in the carbon dioxide torch are converted into carbon monoxide according to the reaction of CO_2 + C → 2CO, reducing a substantial amount of carbon dioxide concentration in the torch. In this regards, the microwave plasma torch may be one of the best ways of converting the carbon dioxides into useful new materials. - Highlights: • Carbon dioxide gas produces a plasma-torch by making use of 2.45 GHz microwaves. • The temperature measurement of torch flame by optical spectroscopy. • Disintegration of carbon dioxide into carbon monoxide and oxygen atom. • Emission profiles of carbon monoxide confirm disintegration theory. • Conversion of carbon dioxide into carbon monoxide in the plasma torch. - This article presents carbon-dioxide plasma torch operated by microwaves and its applications to regeneration of new resources, eliminating carbon dioxide molecules.

Carbon dioxide fluid-flow modeling and injectivity calculations

Science.gov (United States)

Burke, Lauri

2011-01-01

At present, the literature lacks a geologic-based assessment methodology for numerically estimating injectivity, lateral migration, and subsequent long-term containment of supercritical carbon dioxide that has undergone geologic sequestration into subsurface formations. This study provides a method for and quantification of first-order approximations for the time scale of supercritical carbon dioxide lateral migration over a one-kilometer distance through a representative volume of rock. These calculations provide a quantified foundation for estimating injectivity and geologic storage of carbon dioxide.

Supercritical carbon dioxide: a solvent like no other

Directory of Open Access Journals (Sweden)

Jocelyn Peach

2014-08-01

Full Text Available Supercritical carbon dioxide (scCO2 could be one aspect of a significant and necessary movement towards green chemistry, being a potential replacement for volatile organic compounds (VOCs. Unfortunately, carbon dioxide has a notoriously poor solubilising power and is famously difficult to handle. This review examines attempts and breakthroughs in enhancing the physicochemical properties of carbon dioxide, focusing primarily on factors that impact solubility of polar and ionic species and attempts to enhance scCO2 viscosity.

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

International Nuclear Information System (INIS)

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

2001-01-01

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, ''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. Testing conducted previously confirmed that the reaction rate and achievable CO(sub 2) capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO(sub 2) and H(sub 2)O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed-bed, fluidized-bed, and transport

CARBON DIOXIDE CAPTURE FROM FLUE GAS USING DRY REGENERABLE SORBENTS

Energy Technology Data Exchange (ETDEWEB)

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

2001-10-01

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, ''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. Testing conducted previously confirmed that the reaction rate and achievable CO{sub 2} capacity of sodium carbonate decreased with increasing temperature, and that the global rate of reaction of sodium carbonate to sodium bicarbonate increased with an increase in both CO{sub 2} and H{sub 2}O concentrations. Energy balance calculations indicated that the rate of heat removal from the particle surface may determine the reaction rate for a particular particle system. This quarter, thermogravimetric analyses (TGA) were conducted which indicated that calcination of sodium bicarbonate at temperatures as high as 200 C did not cause a significant decrease in activity in subsequent carbonation testing. When sodium bicarbonate was subjected to a five cycle calcination/carbonation test, activity declined slightly over the first two cycles but was constant thereafter. TGA tests were also conducted with two other potential sorbents. Potassium carbonate was found to be less active than sodium carbonate, at conditions of interest in preliminary TGA tests. Sodium carbonate monohydrate showed negligible activity. Testing was also conducted in a 2-inch internal diameter quartz fluidized-bed reactor system. A five cycle test demonstrated that initial removals of 10 to 15 percent of the carbon dioxide in a simulated flue gas could be achieved. The carbonation reaction proceeded at temperatures as low as 41 C. Future work by TGA and in fixed

The role of renewable bioenergy in carbon dioxide sequestration

Energy Technology Data Exchange (ETDEWEB)

Kinoshita, C.M. [Hawaii Natural Energy Inst., Honolulu, HI (United States)

1993-12-31

The use of renewable resources represents a sound approach to producing clean energy and reducing the dependence on diminishing reserves of fossil fuels. Unfortunately, the widespread interest in renewable energy in the 1970s, spurred by escalating fossil fuel prices, subsided with the collapse of energy prices in the mid 1980s. Today, it is largely to reverse alarming environmental trends, particularly the buildup of atmospheric carbon dioxide, rather than to reduce the cost of energy, that renewable energy resources are being pursued. This discussion focuses on a specific class of renewable energy resources - biomass. Unlike most other classes of renewable energy touted for controlling atmospheric carbon dioxide concentrations, e.g., hydro, direct solar, wind, geothermal, and ocean thermal, which produce usable forms of energy while generating little or no carbon dioxide emissions, bioenergy almost always involves combustion and therefore generates carbon dioxide; however, if used on a sustained basis, bio-energy would not contribute to the build-up of atmospheric carbon dioxide because the amount released in combustion would be balanced by that taken up via photosynthesis. It is in that context, i.e., sustained production of biomass as a modern energy carrier, rather than reforestation for carbon sequestration, that biomass is being discussed here, since biomass can play a much greater role in controlling global warming by displacing fossil fuels than by being used strictly for carbon sequestration (partly because energy crop production can reduce fossil carbon dioxide emissions indefinitely, whereas under the reforestation strategy, carbon dioxide abatement ceases at forest maturity).

Modelling of cyclopentane promoted gas hydrate systems for carbon dioxide capture processes

DEFF Research Database (Denmark)

Herslund, Peter Jørgensen; Thomsen, Kaj; Abildskov, Jens

2014-01-01

A thermodynamic model based on the Cubic-Plus-Association equation of state and the van der Waals-Platteeuw hydrate model is applied to perform a thermodynamic evaluation of gas hydrate forming systems relevant for post-combustion carbon dioxide capture.A modelling study of both fluid phase...... behaviour and hydrate phase behaviour is presented. Cycloalkanes ranging from cyclopropane to cyclohexane, represents a challenge for CPA, both in the description of the pure component densities and for liquid-liquid equilibrium (LLE) in the binary systems with water. It is concluded that an insufficient...

Flue gas injection into gas hydrate reservoirs for methane recovery and carbon dioxide sequestration

International Nuclear Information System (INIS)

Yang, Jinhai; Okwananke, Anthony; Tohidi, Bahman; Chuvilin, Evgeny; Maerle, Kirill; Istomin, Vladimir; Bukhanov, Boris; Cheremisin, Alexey

2017-01-01

Highlights: • Flue gas was injected for both methane recovery and carbon dioxide sequestration. • Kinetics of methane recovery and carbon dioxide sequestration was investigated. • Methane-rich gas mixtures can be produced inside methane hydrate stability zones. • Up to 70 mol% of carbon dioxide in the flue gas was sequestered as hydrates. - Abstract: Flue gas injection into methane hydrate-bearing sediments was experimentally investigated to explore the potential both for methane recovery from gas hydrate reservoirs and for direct capture and sequestration of carbon dioxide from flue gas as carbon dioxide hydrate. A simulated flue gas from coal-fired power plants composed of 14.6 mol% carbon dioxide and 85.4 mol% nitrogen was injected into a silica sand pack containing different saturations of methane hydrate. The experiments were conducted at typical gas hydrate reservoir conditions from 273.3 to 284.2 K and from 4.2 to 13.8 MPa. Results of the experiments show that injection of the flue gas leads to significant dissociation of the methane hydrate by shifting the methane hydrate stability zone, resulting in around 50 mol% methane in the vapour phase at the experimental conditions. Further depressurisation of the system to pressures well above the methane hydrate dissociation pressure generated methane-rich gas mixtures with up to 80 mol% methane. Meanwhile, carbon dioxide hydrate and carbon dioxide-mixed hydrates were formed while the methane hydrate was dissociating. Up to 70% of the carbon dioxide in the flue gas was converted into hydrates and retained in the silica sand pack.

It is time to put carbon dioxide to work

Energy Technology Data Exchange (ETDEWEB)

Lipinsky, E.S. [Battelle, Columbus, OH (United States)

1993-12-31

The need to control emissions of carbon dioxide into the atmosphere is the subject of vigorous debate at this time. There is growing evidence that rising levels of carbon dioxide increase global warming, with perhaps highly adverse impacts for the human economy. There are calls for carbon taxes and other harsh measures. Japan has established a national goal of holding carbon dioxide emissions in the year 2000 to 1990 levels. I hope that this conference will be a turning point in the United States position on this issue. The current major end uses for CO{sub 2} include refrigeration, beverage carbonation, soda ash production, fire fighting, and urea fertilizer production. They are all based on chemistry that would not surprise a good chemist of the 19th century. Consumption of carbon dioxide in synthesis of industrial chemicals is limited. Usually one explains low production of chemicals from a candidate feedstock in terms of poor availability, price, purity, or reactivity. We can eliminate the first three as the causes of the underutilization of carbon dioxide.

Tourism Transport, Technology, and Carbon Dioxide Emissions

NARCIS (Netherlands)

Peeters, P.M.

2010-01-01

Technological development from horse-drawn carriages to the new Airbus A380 has led to a remarkable increase in both the capacity and speed of tourist travel. This development has an endogenous systemic cause and will continue to increase carbon dioxide emissions/energy consumption if left

The carbon dioxide thermometer and the cause of global warming

International Nuclear Information System (INIS)

Calder, Nigel

1999-01-01

Carbon dioxide in the air may be increasing because the world is warming. This possibility, which contradicts the hypothesis of an enhanced greenhouse warming driven by manmade emissions, is here pursued in two ways. First, increments in carbon dioxide are treated as readings of a natural thermometer that tracks global and hemispheric temperature deviations, as gauged by meteorologists' thermometers. Calibration of the carbon dioxide thermometer to conventional temperatures then leads to a history of carbon dioxide since 1856 that diverges from the ice-core record. Secondly, the increments of carbon dioxide can also be accounted for, without reference to temperature, by the combined effects of cosmic rays, El Nino and volcanoes. The most durable effect is due to cosmic rays. A solar wind history, used as a long-term proxy for the cosmic rays, gives a carbon dioxide history similar to that inferred from the global temperature deviations. (author)

Handbook of methods for the analysis of the various parameters of the carbon dioxide system in sea water. Version 2

Energy Technology Data Exchange (ETDEWEB)

Dickson, A.G.; Goyet, C. [eds.

1994-09-01

The collection of extensive, reliable, oceanic carbon data is a key component of the Joint Global Ocean Flux Study (JGOFS). A portion of the US JGOFS oceanic carbon dioxide measurements will be made during the World Ocean Circulation Experiment Hydrographic Program. A science team has been formed to plan and coordinate the various activities needed to produce high quality oceanic carbon dioxide measurements under this program. This handbook was prepared at the request of, and with the active participation of, that science team. The procedures have been agreed on by the members of the science team and describe well tested methods. They are intended to provide standard operating procedures, together with an appropriate quality control plan, for measurements made as part of this survey. These are not the only measurement techniques in use for the parameters of the oceanic carbon system; however, they do represent the current state-of-the-art for ship-board measurements. In the end, the editors hope that this handbook can serve widely as a clear and unambiguous guide to other investigators who are setting up to analyze the various parameters of the carbon dioxide system in sea water.

Pressure pumping of carbon dioxide from soil

Science.gov (United States)

E. S. Takle; J. R. Brandle; R. A. Schmidt; R. Garcia; I. V. Litvina; G. Doyle; X. Zhou; Q. Hou; C. W. Rice; W. J. Massman

2000-01-01

Recent interest in atmospheric increases in carbon dioxide have heightened the need for improved accuracy in measurements of fluxes of carbon dioxide from soils. Diffusional movement has long been considered the dominant process by which trace gases move from the subsurface source to the surface, although there has been some indication that atmospheric pressure...

Carbon dioxide inhalation induces dose-dependent and age-related negative affectivity.

Directory of Open Access Journals (Sweden)

Eric J Griez

Full Text Available BACKGROUND: Carbon dioxide inhalation is known to induce an emotion similar to spontaneous panic in Panic Disorder patients. The affective response to carbon dioxide in healthy subjects was not clearly characterized yet. METHODOLOGY/PRINCIPAL FINDINGS: Sixty-four healthy subjects underwent a double inhalation of four mixtures containing respectively 0, 9, 17.5 and 35% CO(2 in compressed air, following a double blind, cross-over, randomized design. Affective responses were assessed according to DSM IV criteria for panic, using an Electronic Visual Analogue Scale and the Panic Symptom List. It was demonstrated that carbon dioxide challenges induced a dose dependent negative affect (p<0.0001. This affect was semantically identical to the DSM IV definition of panic. Older individuals were subjectively less sensitive to Carbon Dioxide (p<0.05. CONCLUSIONS/SIGNIFICANCE: CO(2 induced affectivity may lay on a continuum with pathological panic attacks. Consistent with earlier suggestions that panic is a false biological alarm, the affective response to CO(2 may be part of a protective system triggered by suffocation and acute metabolic distress.

End-tidal carbon dioxide (ETCO2) can replace methods for measuring partial pressure of carbon dioxide (PCO2) in pigs

DEFF Research Database (Denmark)

Alstrup, Aage Kristian Olsen

2017-01-01

We compared end-tidal carbon dioxide (ETCO2) with partial pressure of carbon dioxide (PCO2) in domestic pigs anesthetized for neuroscience. There was good agreement between ETCO2 and PCO2 under both hypocapnia, normocapnia, and hypercapnia conditions. ETCO2 saves time by continually providing...

Carbon dioxide flux measurements from a coastal Douglas-fir forest floor

International Nuclear Information System (INIS)

Drewitt, G.B.

2002-01-01

This thesis examined the process that affects the exchange of carbon between the soil and the atmosphere with particular attention to the large amounts of carbon stored in soils in the form of decaying organic matter. This forest floor measuring study was conducted in 2000 at a micro-meteorological tower flux site in a coastal temperature Douglas-fir forest. The measuring study involved half hourly measurements of both carbon dioxide and below-ground carbon dioxide storage. Measurements were taken at 6 locations between April and December to include a large portion of the growing season. Eddy covariance (EC) measurements of carbon dioxide flux above the forest floor over a two month period in the summer and the autumn were compared with forest floor measurements. Below-ground carbon dioxide mixing ratios of soil air were measured at 6 depths between 0.02 to 1 m using gas diffusion probes and a syringe sampling method. Maximum carbon dioxide fluxes measured by the soil chambers varied by a factor of 3 and a high spatial variability in soil carbon dioxide flux was noted. Forest floor carbon dioxide fluxes measured by each of the chambers indicated different sensitivities to soil temperature. Hysteresis in the flux temperature relationship over the year was evident. Reliable below-canopy EC measurements of the forest floor carbon dioxide flux were difficult to obtain because of the every low wind speeds below the forest canopy. The amount of carbon dioxde present in the soil increased rapidly with depth near the surface but less rapidly deeper in the soil. It was suggested that approximately half of the carbon dioxide produced below-ground comes from between the soil surface and the first 0.15 m of depth. Carbon dioxide fluxes from the floor of a Douglas-fir forest were found to be large compared to other, less productive ecosystems

The carbon dioxide content in ice cores - climatic curves of carbon dioxide. Zu den CO sub 2 -Klimakurven aus Eisbohrkernen

Energy Technology Data Exchange (ETDEWEB)

Heyke, H.E.

1992-05-01

The 'greenhouse effect', which implies a temperature of 15 deg C as against -18 deg C, owes its effect to 80% from water (clouds and gaseous phase) and to 10% from carbon dioxide, besides other components. Whereas water is largely unaccounted for, carbon dioxide has been postulated as the main cause of anticipated climatic catastrophe. The carbon dioxide concentration in the atmosphere has risen presently to such levels that all previous figures seem to have been left far behind. The reference point is the concentration of carbon dioxide in the air bubbles trapped in ice cores of Antartic and Greenland ice dated 160 000 years ago, which show much lower values than at present. A review of the most relevant publications indicates that many basic laws of chemistry seem to have been left largely unconsidered and experimental errors have made the results rather doubtful. Appropriate arguments have been presented. The investigations considered should be repeated under improved and more careful conditions. (orig.).

Ultrapulse carbon dioxide laser ablation of xanthelasma palpebrarum: A case series

Directory of Open Access Journals (Sweden)

Vikas Pathania

2015-01-01

Full Text Available Context: Xanthelasma palpebrarum is the most common form of xanthomas. Albeit a benign entity, it is cosmetically disturbing and a frequently recurring dermatologic referral. Although the classical treatment option remains surgical excision, alternatively, chemical cauterization, cryosurgery and electrofulguration have all been tried in the past with mixed results. The use of laser systems such as carbon dioxide laser, Erb:YAG laser, Q-switched Nd:YAG laser, diode laser, pulsed dye laser and KTP laser have become popular in the treatment of these lesions. Recent literature suggests minimal pigmentary changes and scarring with the use of ultrapulse carbon dioxide laser treatment of these lesions. Aim: To study and evaluate the effectiveness of ultrapulse carbon dioxide laser ablation for treatment of xanthelasma palpebrarum. Materials and Methods: 10 patients presenting with bilateral xanthelasma palpebrarum, new and with recurrence were studied for results after a single treatment with ultrapulse carbon dioxide laser (10,600 nm; 100-200 Hz; 200-400 μsec. The follow-up time was 9 months. Results: All lesions were treatable with a single-laser treatment session. Two patients (20% developed recurrence during the follow-up period. Side effects included post inflammatory hyperpigmentation in two patients (20%, but no visible scarring was observed. Conclusions: The ultrapulse carbon dioxide laser is an effective and safe therapeutic alternative in treatment of xanthelasma palpebrarum.

Miniature Carbon Dioxide Sensor for Small Unmanned Aircraft Systems, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — There is a growing need to develop improved technologies for precise airborne measurements of carbon dioxide, CO2. CO2 measurements are of great importance to many...

Supercritical carbon dioxide for textile applications and recent developments

Science.gov (United States)

Eren, H. A.; Avinc, O.; Eren, S.

2017-10-01

In textile industry, supercritical carbon dioxide (scCO2), possessing liquid-like densities, mostly find an application on textile dyeing processes such as providing hydrophobic dyes an advantage on dissolving. Their gas-like low viscosities and diffusion properties can result in shorter dyeing periods in comparison with the conventional water dyeing process. Supercritical carbon dioxide dyeing is an anhydrous dyeing and this process comprises the usage of less energy and chemicals when compared to conventional water dyeing processes leading to a potential of up to 50% lower operation costs. The advantages of supercritical carbon dioxide dyeing method especially on synthetic fiber fabrics hearten leading textile companies to alter their dyeing method to this privileged waterless dyeing technology. Supercritical carbon dioxide (scCO2) waterless dyeing is widely known and applied green method for sustainable and eco-friendly textile industry. However, not only the dyeing but also scouring, desizing and different finishing applications take the advantage of supercritical carbon dioxide (scCO2). In this review, not only the principle, advantages and disadvantages of dyeing in supercritical carbon dioxide but also recent developments of scCO2 usage in different textile processing steps such as scouring, desizing and finishing are explained and commercial developments are stated and summed up.

Combined effect of sulfur dioxide and carbon dioxide gases on mold fungi

Energy Technology Data Exchange (ETDEWEB)

Kochurova, A.I.; Karpova, T.N.

1974-01-01

Sulfur dioxide at 0.08% killed Penicillium expansum, Stemphylium macrosporium, and Botrytis cinerea within 24 hours. At 0.2%, it killed P. citrinum, Alternaria tenuis, and Fusarium moniliforme. Sulfur dioxide (at 0.04%) and Sulfur dioxide-carbon dioxide mixtures (at 0.02 and 5% respectively) completely suppressed the growth of P. citrinum, P. expansum, P. rubrum, A. tenuis, S. macrosporium, B. cinerea, and F. moniliforme in laboratory experiments. 1 table.

Application of a systematic methodology for sustainable carbon dioxide utilization process design

DEFF Research Database (Denmark)

Plaza, Cristina Calvera; Frauzem, Rebecca; Gani, Rafiqul

than carbon capture and storage. To achieve this a methodology is developed to design sustainable carbon dioxide utilization processes. First, the information on the possible utilization alternatives is collected, including the economic potential of the process and the carbon dioxide emissions...... emission are desired in order to reduce the carbon dioxide emissions. Using this estimated preliminary evaluation, the top processes, with the most negative carbon dioxide emission are investigated by rigorous detailed simulation to evaluate the net carbon dioxide emissions. Once the base case design...

Biocatalytic methanation of hydrogen and carbon dioxide in an anaerobic three-phase system.

Science.gov (United States)

Burkhardt, M; Koschack, T; Busch, G

2015-02-01

A new type of anaerobic trickle-bed reactor was used for biocatalytic methanation of hydrogen and carbon dioxide under mesophilic temperatures and ambient pressure in a continuous process. The conversion of gaseous substrates through immobilized hydrogenotrophic methanogenic archaea in a biofilm is a unique feature of this type of reactor. Due to the formation of a three-phase system on the carrier surface and operation as a plug flow reactor without gas recirculation, a complete reaction could be observed. With a methane concentration higher than c(CH4) = 98%, the product gas exhibits a very high quality. A specific methane production of P(CH4) = 1.49 Nm(3)/(m(3)(SV) d) was achieved at a hydraulic loading rate of LR(H2) = 6.0 Nm(3)/(m(3)(SV) d). The relation between trickle flow through the reactor and productivity could be shown. An application for methane enrichment in combination with biogas facilities as a source of carbon dioxide has also been positively proven. Copyright © 2014 Elsevier Ltd. All rights reserved.

Nuclear power and carbon dioxide free automobiles

International Nuclear Information System (INIS)

Pendergast, D.R.

1999-01-01

Nuclear energy has been developed as a major source of electric power in Canada. Electricity from nuclear energy already avoids the emission of about 100 million tonnes of carbon dioxide to the atmosphere in Canada. This is a significant fraction of the 619 million tonnes of Canadian greenhouse gas emissions in 1995. However, the current scope of application of electricity to end use energy needs in Canada limits the contribution nuclear energy can make to carbon dioxide emission reduction. Nuclear energy can also contribute to carbon dioxide emissions reduction through expansion of the use of electricity to less traditional applications. Transportation, in particular contributed 165 million tonnes of carbon dioxide to the Canadian atmosphere in 1995. Canada's fleet of personal vehicles consisted of 16.9 million cars and light trucks. These vehicles were driven on average 21,000 km/year and generated 91 million tonnes of greenhouse gases expressed as a C02 equivalent. Technology to improve the efficiency of cars is under development which is expected to increase the energy efficiency from the 1995 level of about 10 litres/100 km of gasoline to under 3 litres/100km expressed as an equivalent referenced to the energy content of gasoline. The development of this technology, which may ultimately lead to the practical implementation of hydrogen as a portable source of energy for transportation is reviewed. Fuel supply life cycle greenhouse gas releases for several personal vehicle energy supply systems are then estimated. Very substantial reductions of greenhouse gas emissions are possible due to efficiency improvements and changing to less carbon intensive fuels such as natural gas. C02 emissions from on board natural gas fueled versions of hybrid electric cars would be decreased to approximately 25 million t/year from the current 91 million tonnes/year. The ultimate reduction identified is through the use of hydrogen fuel produced via electricity from CANDU power

27 CFR 27.42a - Still wines containing carbon dioxide.

Science.gov (United States)

2010-04-01

... carbon dioxide. 27.42a Section 27.42a Alcohol, Tobacco Products and Firearms ALCOHOL AND TOBACCO TAX AND... On Imported Distilled Spirits, Wines, and Beer Wines § 27.42a Still wines containing carbon dioxide. Still wines may contain not more than 0.392 gram of carbon dioxide per 100 milliliters of wine; except...

Beneficial Use of Carbon Dioxide in Precast Concrete Production

Energy Technology Data Exchange (ETDEWEB)

Shao, Yixin [McGill Univ., Montreal, QC (Canada)

2014-06-26

The feasibility of using carbon dioxide as feedstock in precast concrete production is studied. Carbon dioxide reacts with calcium compounds in concrete, producing solid calcium carbonates in binding matrix. Two typical precast products are examined for their capacity to store carbon dioxide during the production. They are concrete blocks and fiber-cement panels. The two products are currently mass produced and cured by steam. Carbon dioxide can be used to replace steam in curing process to accelerate early strength, improve the long-term durability and reduce energy and emission. For a reaction within a 24-hour process window, the theoretical maximum possible carbon uptake in concrete is found to be 29% based on cement mass in the product. To reach the maximum uptake, a special process is developed to promote the reaction efficiency to 60-80% in 4-hour carbon dioxide curing and improve the resistance to freeze-thaw cycling and sulfate ion attack. The process is also optimized to meet the project target of $10/tCO₂ in carbon utilization. By the use of self-concentrating absorption technology, high purity CO₂ can be produced at a price below $40/t. With low cost CO₂ capture and utilization technologies, it is feasible to establish a network for carbon capture and utilization at the vicinity of carbon sources. If all block produces and panel producers in United States could adopt carbon dioxide process in their production in place of steam, carbon utilization in these two markets alone could consume more than 2 Mt CO₂/year. This capture and utilization process can be extended to more precast products and will continue for years to come.

Plant growth and physiology of vegetable plants as influenced by carbon dioxide environment

International Nuclear Information System (INIS)

Ito, Tadashi

1973-01-01

In order to obtain basic knowledge on the increased giving of carbon dioxide to vegetables, the carbon dioxide environment in growing houses was analyzed, and the physiological and ecological properties of vegetables cultivated in carbon dioxide environment were elucidated. To improve the carbon dioxide environment, giving increased quantity of carbon dioxide, air flow, ventilation, and others were examined. The concentration of carbon dioxide began to decrease when the illumination intensity on growing layer reached 1 -- 1.5 lux, owing to the photo-synthetic activity of vegetables, and decreased rapidly at 3 -- 5 lux. The lowering of carbon dioxide concentration lowered the photo-synthesis of vegetables extremely, and the transfer of synthesized carbohydrate to roots was obstructed. The effect suffered in low carbon dioxide concentration left some aftereffect even after ventilation and the recovery of carbon dioxide concentration. But this aftereffect was not observed in case of cucumber. To improve carbon dioxide environment, the air flow or ventilation required for minimizing the concentration lowering was determined, but giving increased quantity of carbon dioxide was most effective. The interaction of carbon dioxide concentration and light was examined regarding the effect on photo-synthesis, and some knowledge of practical application was obtained. The effect of giving more carbon dioxide was more remarkable as the treatment was given to younger seedlings and in the period when the capacity of absorbing assimilation products was higher. (Kako, I.)

Carbon monoxide and carbon dioxide interaction with tantalum

International Nuclear Information System (INIS)

Belov, V.D.; Ustinov, Yu.K.; Komar, A.P.

1978-01-01

The adsorption of carbon monoxide and carbon dioxide on tantalum and the dissolution of these gases in the adsorbent at T >= 300 K have been studied. The flash-filament method (FFM) in a monopole mass-spectrometer and a field emission microscopy was used in the same apparatus. Carbon monoxide and carbon dioxide dissociate on the tantalum surface, carbon monoxide being desorbed in both cases during the flash. The desorption curves of CO reveal three different binding states: two of them (α and β' 1 ) for the adsorbed particles whereas the high temperature desorption state relates to the adsorbate dissolved in the metal. For the β' 1 state of CO the activation energy, the pre-exponential factor and the kinetic order in the kinetic equation of desorption have been estimated. They turned out to be E = 110 kcal/mol, C = 3 X 10 12 sec -1 , and γ = 1. The activation energy of diffusion for CO in tantalum and the energy of outgassing for the metal were found to be 9.4 and 49 kcal/mole, respectively. (Auth.)

Carbon monoxide and carbon dioxide interaction with tantalum

Energy Technology Data Exchange (ETDEWEB)

Belov, V D; USTINOV, YU K; KOMAR, A P [AN SSSR, LENINGRAD. FIZIKO-TEKHNICHESKIJ INST.

1978-03-01

The adsorption of carbon monoxide and carbon dioxide on tantalum and the dissolution of these gases in the adsorbent at T >= 300 K have been studied. The flash-filament method (FFM) in a monopole mass-spectrometer and a field emission microscopy was used in the same apparatus. Carbon monoxide and carbon dioxide dissociate on the tantalum surface, carbon monoxide being desorbed in both cases during the flash. The desorption curves of CO reveal three different binding states: two of them (..cap alpha.. and ..beta..'/sub 1/) for the adsorbed particles whereas the high temperature desorption state relates to the adsorbate dissolved in the metal. For the ..beta..'/sub 1/ state of CO the activation energy, the pre-exponential factor and the kinetic order in the kinetic equation of desorption have been estimated. They turned out to be E = 110 kcal/mol, C = 3 X 10/sup 12/ sec/sup -1/, and ..gamma.. = 1. The activation energy of diffusion for CO in tantalum and the energy of outgassing for the metal were found to be 9.4 and 49 kcal/mole, respectively.

Biofixation of Carbon dioxide by Chlamydomonas sp. in a Tubular Photobioreactor

Directory of Open Access Journals (Sweden)

H Hadiyanto

2012-02-01

Full Text Available The biogas production from anaerobic digestion is a potential fuel for power generators application, if biogas can be upgraded to the same standards as fossil natural gas by CO2, H2S, and other non-combustible component removal. Microalgae Chlamydomonas sp. has potency to biofix the carbon dioxide and can be used as an additional food ingredient. The variations of flow rate and carbon dioxide concentration in the process resulting different value of biomass production and carbon dioxide biofixation. Biomass production at 40% carbon dioxide concentration obtained 5.685 gr/dm3 at 10% carbon dioxide concentration obtained 4.892 gr/dm3. The greatest value of carbon dioxide absorption occurs at a 40% concentration amounting to 12.09%. The rate of growth and productivity of microalgae tend to rise in 10% and 20% (%v carbon dioxide concentration, but began started a constant at 30% and 40% (%v carbon dioxide concentration. Biomass production tends to increase in light conditions while a constant in dark conditions. This study used Chlamydomonas sp. as media culture and performed on bubble column and tubular reactor with 6 litres of culture medium at a temperature of 28oC and atmospheric pressure.

Semiconductor-Based Photoelectrochemical Conversion of Carbon Dioxide: Stepping Towards Artificial Photosynthesis.

Science.gov (United States)

Pang, Hong; Masuda, Takuya; Ye, Jinhua

2018-01-18

The photoelectrochemical (PEC) carbon dioxide reduction process stands out as a promising avenue for the conversion of solar energy into chemical feedstocks, among various methods available for carbon dioxide mitigation. Semiconductors derived from cheap and abundant elements are interesting candidates for catalysis. Whether employed as intrinsic semiconductors or hybridized with metallic cocatalysts, biocatalysts, and metal molecular complexes, semiconductor photocathodes exhibit good performance and low overpotential during carbon dioxide reduction. Apart from focusing on carbon dioxide reduction materials and chemistry, PEC cells towards standalone devices that use photohybrid electrodes or solar cells have also been a hot topic in recent research. An overview of the state-of-the-art progress in PEC carbon dioxide reduction is presented and a deep understanding of the catalysts of carbon dioxide reduction is also given. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

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

Electrocatalytic process for carbon dioxide conversion

Science.gov (United States)

Masel, Richard I.; Salehi-Khojin, Amin; Kutz, Robert

2017-11-14

An electrocatalytic process for carbon dioxide conversion includes combining a Catalytically Active Element and a Helper Polymer in the presence of carbon dioxide, allowing a reaction to proceed to produce a reaction product, and applying electrical energy to said reaction to achieve electrochemical conversion of said carbon dioxide reactant to said reaction product. The Catalytically Active Element can be a metal in the form of supported or unsupported particles or flakes with an average size between 0.6 nm and 100 nm. The reaction products comprise at least one of CO, HCO.sup.-, H.sub.2CO, (HCO.sub.2).sup.-, H.sub.2CO.sub.2, CH.sub.3OH, CH.sub.4, C.sub.2H.sub.4, CH.sub.3CH.sub.2OH, CH.sub.3COO.sup.-, CH.sub.3COOH, C.sub.2H.sub.6, (COOH).sub.2, (COO.sup.-).sub.2, and CF.sub.3COOH.

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.

Carbon dioxide and the greenhouse effect: an unresolved problem

Energy Technology Data Exchange (ETDEWEB)

Smith, I M

1978-01-01

This paper evaluates current scientific literature concerned with the accumulation of carbon dioxide in the atmosphere. The extent and possible causes of natural variations in global climate are outlined as a background to potential variations due to human activity. Estimates are given on relative contributions of carbon dioxide to the atmosphere due to fossil fuel combustion, deforestation and other land modifications. The possibility of a rise in global temperature as a result of increasing the amount of carbon dioxide in the atmosphere is discussed including model predictions, natural factors which could compensate for or emphasize a warming effect, and the implications if extensive warming actually occurred. Carbon dioxide disposal is discussed but there appears to be no practicable long-term means of accomplishing this. It is concluded that there is no evidence of a rise in global temperature due to carbon dioxide at present. Predictions, which involve a high degree of uncertainty, indicate that the global temperature could rise appreciably in the next century. An increase in precipitation rate is also expected.

Carbon Dioxide Insufflation Increases Colonoscopic Adenoma Detection Rate Compared With Air Insufflation.

Science.gov (United States)

Mills, Christopher D; McCamley, Chere; Swan, Michael P

2018-03-07

To determine the effect of carbon dioxide insufflation on the most important outcome measure of colonoscopic quality: adenoma detection rate (ADR). Bowel cancer is the second most common cause of cancer deaths in males and females in Australia. Carbon dioxide has in recent times become the insufflation methodology of choice for screening colonoscopy for bowel cancer, as this has been shown to have significant advantages when compared with traditional air insufflation. Endoscopies performed over a period of 9 months immediately before and after the implementation of carbon dioxide insufflation at endoscopy centers were eligible for inclusion. The difference in ADR between the carbon dioxide and air insufflation methods was statistically significant, with an increased ADR in the carbon dioxide group. The superiority of carbon dioxide insufflation was sustained with a logistic regression model, which showed ADR was significantly impacted by insufflation method. Carbon dioxide insufflation is known to reduce abdominal pain, postprocedural duration of abdominal pain, abdominal distension, and analgesic requirements. This study represents for the first time the beneficial effect of carbon dioxide insufflation upon the key quality colonoscopy indicator of ADR.

Carbon Dioxide (CO2) in Blood: MedlinePlus Lab Test Information

Science.gov (United States)

... this page: https://medlineplus.gov/labtests/carbondioxideco2inblood.html Carbon Dioxide (CO2) in Blood To use the sharing features ... this page, please enable JavaScript. What is a Carbon Dioxide (CO2) Blood Test? Carbon dioxide (CO2) is an ...

Gettering of carbon dioxide by erbium thin films

International Nuclear Information System (INIS)

Mehrhoff, T.K.

1980-01-01

The interaction of carbon dioxide and erbium thin films is characterized for temperatures in the region of 300 to 900 0 C and partial pressure of carbon dioxide near 5 x 10 -7 Torr. Dynamic film pumping speeds were measured against a mercury diffusion pump of known pumping speed and conductance. A quadrupole mass spectrometer was used to monitor the carbon dioxide flow which originated from a calibrated leak in the 10 -6 standard cm 3 /s range. Data reduction was via a dedicated minicomputer with associated printer/plotter. Temperature ramp experiments with thin erbium films indicated a significant reaction above 300 0 C. The reaction was preceded by the desorption of water vapor, hydrogen and nitrogen and/or carbon monoxide from the film surface

Carbon dioxide elimination and regeneration of resources in a microwave plasma torch.

Science.gov (United States)

Uhm, Han S; Kwak, Hyoung S; Hong, Yong C

2016-04-01

Carbon dioxide gas as a working gas produces a stable plasma-torch by making use of 2.45 GHz microwaves. The temperature of the torch flame is measured by making use of optical spectroscopy and a thermocouple device. Two distinctive regions are exhibited, a bright, whitish region of a high-temperature zone and a bluish, dimmer region of a relatively low-temperature zone. The bright, whitish region is a typical torch based on plasma species where an analytical investigation indicates dissociation of a substantial fraction of carbon dioxide molecules, forming carbon monoxides and oxygen atoms. The emission profiles of the oxygen atoms and the carbon monoxide molecules confirm the theoretical predictions of carbon dioxide disintegration in the torch. Various hydrocarbon materials may be introduced into the carbon dioxide torch, regenerating new resources and reducing carbon dioxide concentration in the torch. As an example, coal powders in the carbon dioxide torch are converted into carbon monoxide according to the reaction of CO2 + C → 2CO, reducing a substantial amount of carbon dioxide concentration in the torch. In this regards, the microwave plasma torch may be one of the best ways of converting the carbon dioxides into useful new materials. Copyright © 2015 Elsevier Ltd. All rights reserved.

Reaction mechanisms for enhancing carbon dioxide mineral sequestration

Science.gov (United States)

Jarvis, Karalee Ann

Increasing global temperature resulting from the increased release of carbon dioxide into the atmosphere is one of the greatest problems facing society. Nevertheless, coal plants remain the largest source of electrical energy and carbon dioxide gas. For this reason, researchers are searching for methods to reduce carbon dioxide emissions into the atmosphere from the combustion of coal. Mineral sequestration of carbon dioxide reacted in electrolyte solutions at 185°C and 2200 psi with olivine (magnesium silicate) has been shown to produce environmentally benign carbonates. However, to make this method feasible for industrial applications, the reaction rate needs to be increased. Two methods were employed to increase the rate of mineral sequestration: reactant composition and concentration were altered independently in various runs. The products were analyzed with complete combustion for total carbon content. Crystalline phases in the product were analyzed with Debye-Scherrer X-ray powder diffraction. To understand the reaction mechanism, single crystals of San Carlos Olivine were reacted in two solutions: (0.64 M NaHCO3/1 M NaCl) and (5.5 M KHCO3) and analyzed with scanning electron microscopy (SEM), transmission electron microscopy (TEM), electron energy loss spectroscopy (EELS), and fluctuation electron microscopy (FEM) to study the surface morphology, atomic crystalline structure, composition and amorphous structure. From solution chemistry studies, it was found that increasing the activity of the bicarbonate ion increased the conversion rate of carbon dioxide to magnesite. The fastest conversion, 60% conversion in one hour, occurred in a solution of 5.5 M KHCO3. The reaction product particles, magnesium carbonate, significantly increased in both number density and size on the coupon when the bicarbonate ion activity was increased. During some experiments reaction vessel corrosion also altered the mineral sequestration mechanism. Nickel ions from vessel

Application of a novel calcium looping process for production of heat and carbon dioxide enrichment of greenhouses

International Nuclear Information System (INIS)

Ramezani, Mohammad; Shah, Kalpit; Doroodchi, Elham; Moghtaderi, Behdad

2015-01-01

Highlights: • The greenhouse calcium looping process was developed by ASPEN Plus simulator. • In this process, the carbonation reaction provides required heat during night time. • The calcination reaction provides required carbon dioxide during day time. • This novel process saves up to 72% energy compared to the fossil fuel burners. • The process thermodynamically attributes to zero emission of carbon dioxide. - Abstract: Greenhouses typically employ conventional burner systems to suffice heat and carbon dioxide required for plant growth. The energy requirement and carbon dioxide emissions from fossil fuel burner are generally high. As an alternative, this paper describes a novel greenhouse calcium looping process which is expected to decrease the energy requirements and associated carbon dioxide emissions. The conceptual design of greenhouse calcium looping process is carried out in the ASPEN Plus v 7.3 simulator. In a greenhouse calcium looping process, the calcination reaction is considered to take place during day time in order to provide the required optimum carbon dioxide between 1000 and 2000 ppm, while the carbonation reaction is occurred during night time to provide required heat. The process simulations carried out in ASPEN indicates that greenhouse calcium looping process theoretically attributes to zero emission of carbon dioxide. Moreover, in a scenario modelling study compared to the conventional natural gas burner system, the heat duty requirements in the greenhouse calcium looping process were found to reduce by as high as 72%

Phase behaviour of the ternary mixture system of poly(L-lactic acid), dichloromethane and carbon dioxide

International Nuclear Information System (INIS)

Gwon, Jungmin; Cho, Dong Woo; Kim, Soo Hyeon; Shin, Hun Yong; Kim, Hwayong

2012-01-01

Highlights: ► The high pressure phase behaviour of poly(L-lactic acid), dichloromethane and carbon dioxide ternary mixtures was measured. ► The experimental data shows the characteristics of the LCST behaviour of polymer–solvent–gas systems. ► The experimental data correlation was performed using the hybrid EOS. - Abstract: In this study, the high pressure phase behaviour of poly(L-lactic acid) (M = 312,000), dichloromethane and carbon dioxide ternary mixtures was studied using a variable volume view cell at temperatures ranging from 313.15 K to 363.15 K and pressures of up to 30.0 MPa as functions of temperature and the CO 2 /dichloromethane mass ratio at poly(L-lactic acid) weight fractions of 1.0%, 2.5% and 3.0%. The experimental results were correlated with the hybrid equation of state for the CO 2 -polymer system using the van der Waals one-fluid mixing rule with three adjustable binary interaction parameters.

Calculation of Binary Adsorption Equilibria: Hydrocarbons and Carbon Dioxide on Activated Carbon

DEFF Research Database (Denmark)

Marcussen, Lis; Krøll, A.

1999-01-01

Binary adsorption equilibria are calculated by means of a mathematical model for multicomponent mixtures combined with the SPD (Spreading Pressure Dependent) model for calculation of activity coefficients in the adsorbed phase. The model has been applied successfully for the adsorption of binary ...... mixtures of hydrocarbons and carbon dioxide on activated carbons. The model parameters have been determined, and the model has proven to be suited for prediction of adsorption equilibria in the investigated systems....

Slurried solid media for simultaneous water purification and carbon dioxide removal from gas mixtures

Science.gov (United States)

Aines, Roger D.; Bourcier, William L.; Viani, Brian

2013-01-29

A slurried solid media for simultaneous water purification and carbon dioxide removal from gas mixtures includes the steps of dissolving the gas mixture and carbon dioxide in water providing a gas, carbon dioxide, water mixture; adding a porous solid media to the gas, carbon dioxide, water mixture forming a slurry of gas, carbon dioxide, water, and porous solid media; heating the slurry of gas, carbon dioxide, water, and porous solid media producing steam; and cooling the steam to produce purified water and carbon dioxide.

Adverse effects of the automotive industry on carbon dioxide emissions

Directory of Open Access Journals (Sweden)

Mpho Bosupeng

2016-05-01

Full Text Available This study aims to determine the effects of the automotive industry on carbon dioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbon dioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbon dioxide emissions in France, Sweden, Spain, Hungary and Japan. In addition, significant relations were observed between output and carbon dioxide discharges in Spain, Canada, India and Japan. Changes in output had substantial impact on emissions in Germany, Canada and India. The results also show that the number of passenger cars influences the magnitude of emissions in multiple economies. In conclusion, the automotive industry has to be considered in policies that aim to reduce carbon dioxide emissions.

Thermoeconomic Optimization of Cascade Refrigeration System Using Mixed Carbon Dioxide and Hydrocarbons at Low Temperature Circuit

Directory of Open Access Journals (Sweden)

Nasruddin Nasruddin

2016-12-01

Full Text Available Many applications and industrial processes require very low cooling temperature, such as cold storage in the biomedical field, requiring temperature below -80 °C. However,single-cycle refrigeration systems can only achieve the effective cooling temperature of -40 °C and, also, the performance of the cycle will decrease drastically for cooling temperatures lower than -35°C. Currently, most of cascade refrigeration systems use refrigerants that have ozone depletion potential (ODP and global warming potential (GWP, therefore, in this study, a cascade system is simulated using a mixture of environmentally friendly refrigerants, namely, carbon dioxide and a hydrocarbon (propane, ethane or ethylene as the refrigerant of the low temperature circuit. A thermodynamic analysis is performed to determine the optimal composition of the mixture of carbon dioxide and hydrocarbons in the scope of certain operating parameters. In addition, an economic analysis was also performed to determine the annual cost to be incurred from the cascade refrigeration system. The multi-objective/thermoeconomic optimization points out optimal operating parameter values of the system, to addressing both exergy efficiency and its relation to the costs to be incurred.

Oxidation suppressing device for steel materials in carbon dioxide cooled reactors

International Nuclear Information System (INIS)

Kawakami, Haruo

1986-01-01

Purpose: To effectively reduce impurity hydrogens in carbon dioxide. Constitution: At least three gas chambers are arranged serially each by way of a valve in a gas flow channel branched from a primary carbon dioxide coolant circuits. Then, a polymeric partition membrane having higher permeation rate for hydrogen than for carbon dioxide, e.g., made of polytrifluorochloroethylene is disposed between first and second gas chambers and, further, the first and the third gas chambers are connected each by way of a valve to the primary carbon dioxide coolant circuit to constitute a gas recovery channel. Carbon dioxide is caused to flow through the channel by means of a pump disposed between the second and third gas chambers, hydrogen as impurity passed through the partition walls is concentrated and discharged out of the channel, while the carbon dioxide with reduced hydrogen content is returned from the first and the third gas chambers to the circuit. (Sekiya, K.)

INTERACTION OF CARBON DIOXIDE WITH CARBON ADSORBENTS BELOW 400 C

Energy Technology Data Exchange (ETDEWEB)

Deitz, V R; Carpenter, F G; Arnold, R G

1963-06-15

The adsorption of carbon dioxide on carbon adsorbents (FT carbon, coconut charcoal, acid-washed bone char) and adsorbents containing basic calcium phosphate (hydroxylapatite, bone char, ash of bone char) was studied. Special consideration was given to the pretreatment of the materials. The carbons equilibrated as rapidly as the temperature; the basic calcium phosphates showed a rapid initial adsorption followed by a very slow rate which continued for days. Linear adsorption isotherms were found on FT carbon and the isosteric heats varied slightiy with coverage. The isotherms for the remaining materials had varying curvature and were for the most part in the same sequence as the estimated surface areas. The isosteric heats of carbon dioxide correlated very well with the magnitude of surface hydroxyl groups, an estimate of which was made from the chemical composition. There appeared to be three increasing levels of interaction: (1) pure physical adsorption; (2) an adsorption complex having 'bicarbonate structure'; and (3) an adsorption complex having 'carbonate structure'. (auth)

High pressure phase behaviour of the binary mixture for the 2-hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, and 2-hydroxypropyl methacrylate in supercritical carbon dioxide

International Nuclear Information System (INIS)

Byun, Hun-Soo; Choi, Min-Yong

2007-01-01

Experimental data of high pressure phase behaviour for binary mixtures of {carbon dioxide + 2-hydroxyethyl methacrylate (HEMA)}, {carbon dioxide + 2-hydroxypropyl acrylate (HPA)}, and {carbon dioxide + 2-hydroxypropyl methacrylate (HPMA)} were determined using a static type with the variable-volume cell at temperatures from (313.2 to 393.2) K and pressures up to 27.10 MPa. Among these binary experimental data, the bubble-point data were correlated with the Peng-Robinson equation of state using a van der Waals one-fluid mixing rule containing two interaction parameters (k ij and η ij ). The (carbon dioxide + HEMA), (carbon dioxide + HPA), and (carbon dioxide + HPMA) systems exhibit type-I phase behaviour. At constant pressure, the solubility of HEMA, HPA, and HPMA for the (Carbon dioxide + HEMA), (carbon dioxide + HPA), and (carbon dioxide + HPMA) systems increases as the temperature increases

Natural deep eutectic solvents (NADES) as green solvents for carbon dioxide capture

Science.gov (United States)

Mulia, Kamarza; Putri, Sylvania; Krisanti, Elsa; Nasruddin

2017-03-01

This study was conducted to determine the effectiveness of Natural Deep Eutectic Solvent (NADES), consisting of choline chloride and a hydrogen bonding donor (HBD) compound, in terms of carbon dioxide absorption. Solubility of carbon dioxide in NADES was found to be influenced HBD compound used and choline chloride to HBD ratio, carbon dioxide pressure, and contact time. HBD and choline/HBD ratios used were 1,2-propanediol (1:2), glycerol (1:2), and malic acid (1:1). The carbon dioxide absorption measurement was conducted using an apparatus that utilizes the volumetric method. Absorption curves were obtained up to pressures of 30 bar, showing a linear relationship between the amount absorbed and the final pressure of carbon dioxide. The choline and 1,2-propanediol eutectic mixture absorbs the highest amount of carbon dioxide, approaching 0.1 mole-fraction at 3.0 MPa and 50°C. We found that NADES ability to absorb carbon dioxide correlates with its polarity as tested using Nile Red as a solvatochromic probe.

Carbon Dioxide and Global Warming: A Failed Experiment

Science.gov (United States)

Ribeiro, Carla

2014-01-01

Global warming is a current environmental issue that has been linked to an increase in anthropogenic carbon dioxide in the atmosphere. To raise awareness of the problem, various simple experiments have been proposed to demonstrate the effect of carbon dioxide on the planet's temperature. This article describes a similar experiment, which…

Catalyst retention in continuous flow with supercritical carbon dioxide

NARCIS (Netherlands)

Stouten, S.C.; Noel, T.; Wang, Q.; Hessel, V.

2014-01-01

This review discusses the retention of organometallic catalysts in continuous flow processes utilizing supercritical carbon dioxide. Due to its innovative properties, supercritical carbon dioxide offers interesting possibilities for process intensification. As a result of safety and cost

Mass transfer and thermodynamic modeling of carbon dioxide absorption into MEA aqueous solution

Directory of Open Access Journals (Sweden)

Ghaemi Ahad

2017-09-01

Full Text Available In this research, thermodynamic and absorption rate of carbon dioxide in monoethanolamine (MEA solution was investigated. A correlation based on both liquid and a gas phase variable for carbon dioxide absorption rate was presented using the π-Buckingham theorem. The correlation was constructed based on dimensionless numbers, including carbon dioxide loading, carbon dioxide partial pressure, film parameter and the ratio of liquid phase film thickness and gas phase film thickness. The film parameter is used to apply the effect of chemical reactions on absorption rate. A thermodynamic model based on the extended-UNIQUAC equations for the activity coefficients coupled with the Virial equation of state for representing the non-ideality of the vapor phase was used to predict the CO2 solubility in the CO2-MEA-H2O system. The average absolute error of the results for the correlation was 6.4%, which indicates the accuracy of the proposed correlation.

Synthesis pf dimethyl carbonate in supercritical carbon dioxide

Energy Technology Data Exchange (ETDEWEB)

Ballivet-Tkatchenko, D.; Plasseraud, L. [Universite de Bourgogne-UFR Sciences et Techniques, Dijon (France). Lab. de Synthese et Electrosynthese Organometalliques]. E-mail: ballivet@u-bourgogne.fr; Ligabue, R.A. [Pontificia Univ. Catolica do Rio Grande do Sul, Porto Alegre, RS (Brazil). Dept. de Quimica Pura

2006-01-15

The reactivity of carbon dioxide with methanol to form dimethyl carbonate was studied in the presence of the n-butylmethoxytin compounds n-Bu{sub 3}SnOCH{sub 3}, n-Bu{sub 2}Sn(OCH{sub 3}){sub 2}, and [n-Bu{sub 2}(CH{sub 3}O)Sn]{sub 2}O. The reaction occurred under solventless conditions at 423 K and was produced by an increase in CO{sub 2} pressure. This beneficial effect is primarily attributed to phase behavior. The mass transfer under liquid-vapor biphasic conditions was not limiting when the system reached the supercritical state for a CO{sub 2} pressure higher than 16 MPa. Under these conditions, CO{sub 2} acted as a reactant and a solvent. (author)

Ocean Fertilization for Sequestration of Carbon Dioxide from the Atmosphere

Science.gov (United States)

Boyd, Philip W.

The ocean is a major sink for both preindustrial and anthropogenic carbon dioxide. Both physically and biogeochemically driven pumps, termed the solubility and biological pump, respectively Fig.5.1) are responsible for the majority of carbon sequestration in the ocean's interior [1]. The solubility pump relies on ocean circulation - specifically the impact of cooling of the upper ocean at high latitudes both enhances the solubility of carbon dioxide and the density of the waters which sink to great depth (the so-called deepwater formation) and thereby sequester carbon in the form of dissolved inorganic carbon (Fig.5.1). The biological pump is driven by the availability of preformed plant macronutrients such as nitrate or phosphate which are taken up by phytoplankton during photosynthetic carbon fixation. A small but significant proportion of this fixed carbon sinks into the ocean's interior in the form of settling particles, and in order to maintain equilibrium carbon dioxide from the atmosphere is transferred across the air-sea interface into the ocean (the so-called carbon drawdown) thereby decreasing atmospheric carbon dioxide (Fig.5.1).Fig.5.1

Balance and forecasts of french carbon dioxide emissions

International Nuclear Information System (INIS)

1992-11-01

This paper strikes the balance of carbon dioxide emissions in France between 1986 and 1991 and gives forecasts till 2010. Since 1986, France has reduced its efforts for energy conservation and air pollution by carbon dioxide begins to growth again in connection with consumption growth in transport area, development of computer and simulation needs

Modeling of carbon dioxide absorption by aqueous ammonia solutions using the Extended UNIQUAC model

DEFF Research Database (Denmark)

Darde, Victor Camille Alfred; van Well, Willy J. M.; Stenby, Erling Halfdan

2010-01-01

An upgraded version of the Extended UNIQUAC thermodynamic model for the carbon dioxide-ammonia-water system has been developed, based on the original version proposed by Thomsen and Rasmussen. The original model was valid in the temperature range 0-110°C, the pressure range 0-10 MPa...... properties of carbon dioxide and ammonia to supercritical conditions....

Intraosseous Venography with Carbon Dioxide in Percutaneous Vertebroplasty: Carbon Dioxide Retention in Renal Veins

International Nuclear Information System (INIS)

Komemushi, Atsushi; Tanigawa, Noboru; Kariya, Shuji; Kojima, Hiroyuki; Shomura, Yuzo; Tokuda, Takanori; Nomura, Motoo; Terada, Jiro; Kamata, Minoru; Sawada, Satoshi

2008-01-01

The objective of the present study was to determine the frequency of gas retention in the renal vein following carbon dioxide intraosseous venography in the prone position and, while citing references, to examine its onset mechanisms. All percutaneous vertebroplasties performed at our hospital from January to December 2005 were registered and retrospectively analyzed. Of 43 registered procedures treating 79 vertebrae, 28 procedures treating 54 vertebrae were analyzed. Vertebral intraosseous venography was performed using carbon dioxide as a contrast agent in all percutaneous vertebroplasty procedures. In preoperative and postoperative vertebral CT, gas retention in the renal vein and other areas was assessed. Preoperative CT did not show gas retention (0/28 procedures; 0%). Postoperative CT confirmed gas retention in the renal vein in 10 of the 28 procedures (35.7%). Gas retention was seen in the right renal vein in 8 procedures (28.6%), in the left renal vein in 5 procedures (17.9%), in the left and right renal veins in 3 procedures (10.7%), in vertebrae in 22 procedures (78.6%), in the soft tissue around vertebrae in 14 procedures (50.0%), in the spinal canal in 12 procedures (42.9%), and in the subcutaneous tissue in 5 procedures (17.9%). In conclusion, in our study, carbon dioxide gas injected into the vertebra frequently reached and remained in the renal vein.

High-pressure phase equilibria in the (carbon dioxide + 1-hexanol) system

International Nuclear Information System (INIS)

Secuianu, Catinca; Feroiu, Viorel; Geana, Dan

2010-01-01

(Vapour + liquid) equilibria (VLE) and (vapour + liquid + liquid) equilibria (VLLE) data for the (carbon dioxide + 1-hexanol) system were measured at (293.15, 303.15, 313.15, 333.15, and 353.15) K. Phase behaviour measurements were made in a high-pressure visual cell with variable volume, based on the static-analytic method. The pressure range under investigation was between (0.6 and 14.49) MPa. The Soave-Redlich-Kwong (SRK) equation of state (EOS) with classical van der Waals mixing rules (two-parameters conventional mixing rule, 2PCMR), was used in a semi-predictive approach, in order to represent the complex phase behaviour (critical curve, LLV line, isothermal VLE, LLE, and VLLE) of the system. The topology of phase behaviour is reasonably well predicted.

Made-to-order metal-organic frameworks for trace carbon dioxide removal and air capture

KAUST Repository

Shekhah, Osama

2014-06-25

Direct air capture is regarded as a plausible alternate approach that, if economically practical, can mitigate the increasing carbon dioxide emissions associated with two of the main carbon polluting sources, namely stationary power plants and transportation. Here we show that metal-organic framework crystal chemistry permits the construction of an isostructural metal-organic framework (SIFSIX-3-Cu) based on pyrazine/copper(II) two-dimensional periodic 4 4 square grids pillared by silicon hexafluoride anions and thus allows further contraction of the pore system to 3.5 versus 3.84 for the parent zinc(II) derivative. This enhances the adsorption energetics and subsequently displays carbon dioxide uptake and selectivity at very low partial pressures relevant to air capture and trace carbon dioxide removal. The resultant SIFSIX-3-Cu exhibits uniformly distributed adsorption energetics and offers enhanced carbon dioxide physical adsorption properties, uptake and selectivity in highly diluted gas streams, a performance, to the best of our knowledge, unachievable with other classes of porous materials. 2014 Macmillan Publishers Limited.

Evaluating the effectiveness of carbon tax for total emission control of carbon dioxide. Systems analysis of a dynamic environmental-economic model

International Nuclear Information System (INIS)

Tamura, Hiroyuki; Abe, Makoto; Tomiyama, Shinji; Hatono, Itsuo

1999-01-01

This paper deals with how to evaluate the effectiveness of carbon tax (environmental tax) for regulating the carbon dioxide emissions. For this purpose we mainly deal with a primal problem and its dual problem of dynamic linear programming model. The primal problem is formulated by using Leontief type input-output model and the basic idea of commodity stocks. It represents the balance of materials. The dual problem is obtained and interpreted as cash balance. It is clarified in this paper whether the carbon tax is effective to decrease the total amount of carbon dioxide emissions. (author)

Carbon dioxide measurements in the nocturnal boundary layer over Amazonian forest

Directory of Open Access Journals (Sweden)

A. D. Culf

1999-01-01

Full Text Available Measurements of carbon dioxide concentration, temperature and windspeed were made in the nocturnal boundary layer over a tropical forest near Manaus, Brazil using a tethered balloon system. The measurements were made up to a maximum height of 300 m on ten consecutive nights in November 1995. Simultaneous surface flux and in-canopy concentration measurements were made at the surface close to the site. The observation period included several different types of conditions. Generally strong windshear and relatively weak temperature gradients prevented the formation of a strong capping inversion to the nocturnal boundary layer. On some nights, however, the inversion was sufficiently strong that the CO2 concentration at 100 m above the surface exceeded 400 ppm. The concentration within the canopy was largely controlled by the presence of an inversion very close to the canopy surface. The temperature and wind profiles are contrasted with conditions in Randônia, Brazil, where the windshear was found to be weaker and higher carbon dioxide concentrations were observed in the early morning. The difference in carbon dioxide concentrations in the nocturnal boundary layer between dusk and dawn is used to estimate the regional nighttime flux of carbon dioxide. The value obtained generally exceeds the measured surface flux and sometimes exceeds the sum of the surface flux and the in-canopy storage made at the tower site. The reasons for the discrepancy are not clear; either one of the methods is in error or the regional carbon dioxide budget differs significantly from the local budget measured at the tower site.

Relationship between Sampling Distance and Carbon Dioxide Emission under Oil Palm Plantation

Directory of Open Access Journals (Sweden)

Ai Dariah

2013-05-01

Full Text Available A carbon dioxide emission on peatland under oil palm plantation was highly varied due to many factors involved. The objectives of the research were to evaluate the effect of sampling distance from center of oil palm tree on Carbon dioxide flux, and to study the factors that cause variability of carbon dioxide flux on peatland under oil palm plantation. The study was conducted on peatland at Arang-Arang Village, Kumpek Ulu Sub-District, Muaro Jambi District, Jambi Province, on six-years old oil palm plantation. The study was conducted in the form of observational exploratory. Emission measurements were performed on 5 selected oil palm trees at points within 100, 150, 200, 250, 300, 350, and 400 cm from the center of trunk. Carbon dioxide flux was measured using (IRGA, Li-COR 820. The results showed that there was significant correlation between the distance of sampling from center of oil palm tree and Carbon dioxide flux. The farther distance from the tree, the more decreased of Carbon dioxide flux . Before applying fertilizer, variability of soil fertility was not significantly correlated with the flux of Carbon dioxide, so the difference of Carbon dioxide flux based on distance sampling can be caused by root distribution factor. After fertilizer application, variability of Carbon dioxide flux under the oil palm tree were not only affected by differences in root distribution but also greatly influenced by fertilization.

Adverse effects of the automotive industry on carbon dioxide emissions

OpenAIRE

Mpho Bosupeng

2016-01-01

This study aims to determine the effects of the automotive industry on carbon dioxide emissions for the period from 1997 to 2010 for diverse economies, as well as the relationships between carbon dioxide discharges and output. The study applies cointegration and causality tests to validate these associations. The results of the Johansen cointegration test depict long-run associations between the quantity of passenger cars and carbon dioxide emissions in France, Sweden, Spain, Hungary and Japa...

Sequestration of carbon dioxide with hydrogen to useful products

Energy Technology Data Exchange (ETDEWEB)

Adams, Michael W. W.; Kelly, Robert M.; Hawkins, Aaron B.; Menon, Angeli Lal; Lipscomb, Gina Lynette Pries; Schut, Gerrit Jan

2017-03-07

Provided herein are genetically engineered microbes that include at least a portion of a carbon fixation pathway, and in one embodiment, use molecular hydrogen to drive carbon dioxide fixation. In one embodiment, the genetically engineered microbe is modified to convert acetyl CoA, molecular hydrogen, and carbon dioxide to 3-hydroxypropionate, 4-hydroxybutyrate, acetyl CoA, or the combination thereof at levels greater than a control microbe. Other products may also be produced. Also provided herein are cell free compositions that convert acetyl CoA, molecular hydrogen, and carbon dioxide to 3-hydroxypropionate, 4-hydroxybutyrate, acetyl CoA, or the combination thereof. Also provided herein are methods of using the genetically engineered microbes and the cell free compositions.

Gettering of carbon dioxide by erbium thin films

International Nuclear Information System (INIS)

Mehrhoff, T.K.

1980-01-01

The interaction of carbon dioxide and erbium thin films is characterized at 300 to 900 0 C and 5 x 10 -7 torr. Temperature ramp experiments with thin erbium films indicated a significant reaction above 300 0 C, preceded by desorption of water vapor, hydrogen and nitrogen and/or carbon monoxide from the film surface. The sticking coefficients were plotted as a function of Langmuirs of carbon dioxide exposure. Between 400 and 600 0 C, the length of the exposure was found to be more important than the temperature of the exposure in determining the sticking coefficient. Some evolution of carbon monoxide was noted particularly in the 400 to 500 0 C region. An 80% conversion of carbon dioxide to carbon monoxide was measured at 500 0 C. The film pumping speeds were compared with published vapor pressure data for erbium. This comparison indicated that a significant portion of the pumping action observed at temperatures of 800 0 C and above was due to evaporation of erbium metal

An Optimal Centralized Carbon Dioxide Repository for Florida, USA

Directory of Open Access Journals (Sweden)

Brandon Poiencot

2011-03-01

Full Text Available For over a decade, the United States Department of Energy, and engineers, geologists, and scientists from all over the world have investigated the potential for reducing atmospheric carbon emissions through carbon sequestration. Numerous reports exist analyzing the potential for sequestering carbon dioxide at various sites around the globe, but none have identified the potential for a statewide system in Florida, USA. In 2005, 83% of Florida’s electrical energy was produced by natural gas, coal, or oil (e.g., fossil fuels, from power plants spread across the state. In addition, only limited research has been completed on evaluating optimal pipeline transportation networks to centralized carbon dioxide repositories. This paper describes the feasibility and preliminary locations for an optimal centralized Florida-wide carbon sequestration repository. Linear programming optimization modeling is used to plan and route an idealized pipeline network to existing Florida power plants. Further analysis of the subsurface geology in these general locations will provide insight into the suitability of the subsurface conditions and the available capacity for carbon sequestration at selected possible repository sites. The identification of the most favorable site(s is also presented.

Niobium(v) chloride and imidazolium bromides as efficient dual catalyst systems for the cycloaddition of carbon dioxide and propylene oxide

KAUST Repository

Wilhelm, Michael E.; Anthofer, Michael H.; Reich, Robert M.; D'Elia, Valerio; Basset, Jean-Marie; Herrmann, Wolfgang A.; Cokoja, Mirza; Kü hn, Fritz

2014-01-01

The application of niobium(v) chloride and several imidazolium bromides as catalyst systems for the cycloaddition of propylene oxide (PO) with carbon dioxide to propylene carbonate (PC) is reported. A set of 31 different imidazolium bromides has been synthesized with varying substituents at all five imidazolium ring atoms, of which 17 have not been reported before. The impact of different substitution patterns (steric and electronic changes and solubility in PO) at the imidazolium ring on the catalytic activity was investigated. The optimisation of the catalyst structure allows for the valorisation of carbon dioxide under mild reaction conditions with high reaction rates in very good yield and selectivity for PC. This journal is © the Partner Organisations 2014.

Niobium(v) chloride and imidazolium bromides as efficient dual catalyst systems for the cycloaddition of carbon dioxide and propylene oxide

KAUST Repository

Wilhelm, Michael E.

2014-02-19

The application of niobium(v) chloride and several imidazolium bromides as catalyst systems for the cycloaddition of propylene oxide (PO) with carbon dioxide to propylene carbonate (PC) is reported. A set of 31 different imidazolium bromides has been synthesized with varying substituents at all five imidazolium ring atoms, of which 17 have not been reported before. The impact of different substitution patterns (steric and electronic changes and solubility in PO) at the imidazolium ring on the catalytic activity was investigated. The optimisation of the catalyst structure allows for the valorisation of carbon dioxide under mild reaction conditions with high reaction rates in very good yield and selectivity for PC. This journal is © the Partner Organisations 2014.

Electrocatalytic reduction of carbon dioxide to carbon monoxide and methane at an immobilized cobalt protoporphyrin

NARCIS (Netherlands)

Shen, J.; Kortlever, R.; Kas, Recep; Mul, Guido; Koper, M.T.M.

2015-01-01

The electrochemical conversion of carbon dioxide and water into useful products is a major challenge in facilitating a closed carbon cycle. Here we report a cobalt protoporphyrin immobilized on a pyrolytic graphite electrode that reduces carbon dioxide in an aqueous acidic solution at relatively low

Carbon dioxide and nisin act synergistically on Listeria monocytogenes

DEFF Research Database (Denmark)

Nilsson, Lilian; Chen, Y.H.; Chikindas, M.L.

2000-01-01

This paper examines the synergistic action of carbon dioxide and nisin on Listeria monocytogenes Scott A wild-type and nisin-resistant (Nis(r)) cells grown in broth at 4 degrees C. Carbon dioxide extended the lag phase and decreased the specific growth rate of both strains, but to a greater degree...... for cultures in CO2. This synergism between nisin and CO2 was examined mechanistically by following the leakage of carboxyfluorescein (CF) from listerial liposomes. Carbon dioxide enhanced nisin-induced CF leakage, indicating that the synergistic action of CO2 and nisin occurs at the cytoplasmic membrane...

Studies on carbon dioxide power plant, (3)

International Nuclear Information System (INIS)

Akagawa, Koji; Fujii, Terushige; Sakaguchi, Tadashi; Kawabata, Yasusuke; Kuroda, Toshihiro.

1980-01-01

A power generating plant using carbon dioxide instead of water has been studied by the authors, as high efficiency can be obtained in high temperature range (higher than 650 deg C) and turbines become compact as compared with the Rankine steam cycle. In this paper, the theoretical analysis of the dynamic characteristics of this small power generating plant of supercritical pressure and the comparison with the experimental results are reported. In the theoretical analysis, the linear approximation method using small variation method was adopted for solution. Every component was modeled as the concentrated constant system, and the transfer function for each component was determined, then simulation was carried out for the total system synthesizing these components. The approximation of physical values, and the analysis of a plunger pump, a regenerator, a heater, a vapor valve, a turbine and a blower, piping, and pressure drop are described. The response to the stepwise changes of heating, flow rate, opening of a vapor valve and a load control valve for a blower was investigated. The theoretical anaysis and the experimental results were in good agreement, and this analysis is applicable to the carbon dioxide plant of practical scale. (Kako, I.)

Method and apparatus for producing food grade carbon dioxide

International Nuclear Information System (INIS)

Nobles, J.E.; Swenson, L.K.

1984-01-01

A method is disclosed of producing food grade carbon dioxide from an impure carbon dioxide source stream containing contaminants which may include light and heavy hydrocarbons (at least C 1 to C 3 ) and light sulfur compounds such as hydrogen sulfide and carbonyl sulfide as well as heavier sulfur constituents in the nature of mercaptans (RSH) and/or organic mono and disulfides (RSR and RSSR). Nitrogen, water and/or oxygen may also be present in varying amounts in the impure feed stream. The feed gas is first rectified with liquid carbon dioxide condensed from a part of the feed stream to remove heavy hydrocarbons and heavy sulfur compounds, then passed through an absorber to effect removal of the light sulfur compounds, next subjected to an oxidizing atmosphere capable of converting all of the C 2 hydrocarbons and optionally a part of the methane to carbon oxides and water, chilled to condense the water in the remaining gas stream without formation of hydrates, liquefied for ease of handling and storage and finally stripped to remove residual contaminants such as methane, carbon monoxide and nitrogen to produce the final food grade carbon dioxide product

Carbon dioxide enhances fragility of ice crystals

International Nuclear Information System (INIS)

Qin Zhao; Buehler, Markus J

2012-01-01

Ice caps and glaciers cover 7% of the Earth, greater than the land area of Europe and North America combined, and play an important role in global climate. The small-scale failure mechanisms of ice fracture, however, remain largely elusive. In particular, little understanding exists about how the presence and concentration of carbon dioxide molecules, a significant component in the atmosphere, affects the propensity of ice to fracture. Here we use atomic simulations with the first-principles based ReaxFF force field capable of describing the details of chemical reactions at the tip of a crack, applied to investigate the effects of the presence of carbon dioxide molecules on ice fracture. Our result shows that increasing concentrations of carbon dioxide molecules significantly decrease the fracture toughness of the ice crystal, making it more fragile. Using enhanced molecular sampling with metadynamics we reconstruct the free energy landscape in varied chemical microenvironments and find that carbon dioxide molecules affect the bonds between water molecules at the crack tip and decrease their strength by altering the dissociation energy of hydrogen bonds. In the context of glacier dynamics our findings may provide a novel viewpoint that could aid in understanding the breakdown and melting of glaciers, suggesting that the chemical composition of the atmosphere can be critical to mediate the large-scale motion of large volumes of ice.

Integrated Assessment of Carbon Dioxide Removal

Science.gov (United States)

Rickels, W.; Reith, F.; Keller, D.; Oschlies, A.; Quaas, M. F.

2018-03-01

To maintain the chance of keeping the average global temperature increase below 2°C and to limit long-term climate change, removing carbon dioxide from the atmosphere (carbon dioxide removal, CDR) is becoming increasingly necessary. We analyze optimal and cost-effective climate policies in the dynamic integrated assessment model (IAM) of climate and the economy (DICE2016R) and investigate (1) the utilization of (ocean) CDR under different climate objectives, (2) the sensitivity of policies with respect to carbon cycle feedbacks, and (3) how well carbon cycle feedbacks are captured in the carbon cycle models used in state-of-the-art IAMs. Overall, the carbon cycle model in DICE2016R shows clear improvements compared to its predecessor, DICE2013R, capturing much better long-term dynamics and also oceanic carbon outgassing due to excess oceanic storage of carbon from CDR. However, this comes at the cost of a (too) tight short-term remaining emission budget, limiting the model suitability to analyze low-emission scenarios accurately. With DICE2016R, the compliance with the 2°C goal is no longer feasible without negative emissions via CDR. Overall, the optimal amount of CDR has to take into account (1) the emission substitution effect and (2) compensation for carbon cycle feedbacks.

Carbon dioxide inhalation treatments of neurotic anxiety. An overview.

Science.gov (United States)

Wolpe, J

1987-03-01

A lucky chance more than 30 years ago revealed the remarkable efficacy of single inhalations of high concentrations of carbon dioxide in eliminating or markedly reducing free-floating anxiety. The reduction of anxiety lasts for days, weeks, or longer--well beyond the persistence of carbon dioxide in the body. The effects are explicable on the hypothesis that free-floating anxiety is anxiety conditioned to continuously present sources of stimulation, such as background noise or the awareness of space or time, and that the anxiety response habit is weakened when the anxiety is inhibited by the competition of responses that carbon dioxide induces. More recently, it has become apparent that inhalations of carbon dioxide, applied in a different manner, are effective in overcoming maladaptive anxiety responses to specific stimuli, e.g., social stimuli. The substance is also proving to be a valuable resource in the treatment of the common variety of panic attacks.

Carbon dioxide problem: solution by technical countermeasures

Energy Technology Data Exchange (ETDEWEB)

Bach, W

1978-02-15

A rough assessment indicates that anthropogenic influences might raise the mean global surface temperature by 0.8 to 1.2 C in 2000 AD and by 2 to 4 C in 2050 AD. The rapidly increasing levels of atmospheric carbon dioxide are largely responsible for this warming trend. A variety of measures for the reduction of carbon dioxide emissions is presented. One promising approach is to work out a world-wide energy mix that can counteract a temperature increase. (In German)

The study on density change of carbon dioxide seawater solution at high pressure and low temperature

International Nuclear Information System (INIS)

Song, Y.; Chen, B.; Nishio, M.; Akai, M.

2005-01-01

It has been widely considered that the global warming, induced by the increasing concentration of carbon dioxide and other greenhouse gases in the atmosphere, is an environmental task affecting the world economic development. In order to mitigate the concentration of CO 2 in the atmosphere, the sequestration of carbon dioxide into the ocean had been investigated theoretically and experimentally over the last 10 years. In addition to ocean dynamics, ocean geological, and biological information on large space and long time scales, the physical-chemistry properties of seawater-carbon dioxide system at high pressure (P>5.0 MPa) and lower temperature (274.15 K 3 , which is approximately same with that of carbon dioxide freshwater solution, the slope of which is 0.275 g/cm 3

Separation of krypton from carbon dioxide and oxygen with molecular sieves

International Nuclear Information System (INIS)

Forsberg, C.W.

1976-01-01

Molecular sieves were investigated to separate 1 percent mixtures of krypton in gas streams of a few percent oxygen and 90+ percent carbon dioxide. Such a system will be required to concentrate the krypton gas between radioactive krypton off-gas cleanup systems such as KALC (Krypton Absorption in Liquid Carbon Dioxide) and any krypton gas bottling station. Linde 5A molecular sieves were found capable of selectively removing the CO 2 from the gas stream while partially separating the oxygen from the krypton; i.e., effecting a three-component gas separation. This use of molecular sieves differs from standard practice in two respects. First, the bulk of the gas (greater than 90 percent) is removed by molecular sieves rather than the normal practice of using molecular sieves to remove trace impurities. Second, in a single bed two separations occur simultaneously, CO 2 from other gases and krypton from oxygen. The use of molecular sieves for separating krypton and carbon dioxide is superior to alternatives such as CO 2 freezeout and chemical traps when there are only moderate gas flows and there is a need for very high reliability and ease of maintenance

Visual and reversible carbon dioxide sensing enabled by doctor blade coated macroporous photonic crystals.

Science.gov (United States)

Lin, Yi-Han; Suen, Shing-Yi; Yang, Hongta

2017-11-15

With significant impacts of carbon dioxide on global climate change, carbon dioxide sensing is of great importance. However, most of the existing sensing technologies are prone to interferences from carbon monoxide, or suffer from the use of sophisticated instruments. This research reports the development of reproducible carbon dioxide sensor using roll-to-roll compatible doctor blade coated three-dimensional macroporous photonic crystals. The pores are functionalized with amine groups to allow the reaction with carbon dioxide in the presence of humidity. The adsorption of carbon dioxide leads to red-shift and amplitude reduction of the optical stop bands, resulting in carbon dioxide detection with visible readout. The dependences of the diffraction wavelength on carbon dioxide partial pressure for various amine-functionalized photonic crystals and different humidities in the environment are systematically investigated. In addition, the reproducibility of carbon dioxide sensing has also been demonstrated in this research. Copyright © 2017 Elsevier Inc. All rights reserved.

Oxygen Recovery via Carbon Dioxide Electrolysis with Microtubular Solid Oxide Cells

Data.gov (United States)

National Aeronautics and Space Administration — Carbon dioxide reduction is considered a major shortcoming for the current Atmosphere Revitalization System. Novel technologies are desired so that the oxygen...

46 CFR 167.45-45 - Carbon dioxide fire-extinguishing system requirements.

Science.gov (United States)

2010-10-01

... SCHOOLS PUBLIC NAUTICAL SCHOOL SHIPS Special Firefighting and Fire Prevention Requirements § 167.45-45... school ship propelled by internal combustion engines, the quantity of carbon dioxide required may be... arrangement of the piping shall be such as to give a general and fairly uniform distribution over the entire...

High-pressure phase behavior of systems with ionic liquids: Part V. The binary system carbon dioxide+1-butyl-3-methylimidazolium tetrafluoroborate

NARCIS (Netherlands)

Kroon, M.C.; Shariati - Sarabi, A.; Costantini, M.; Spronsen, van J.; Witkamp, G.J.; Sheldon, R.A.; Peters, C.J.

2005-01-01

The phase behavior of the binary system consisting of the supercritical fluid carbon dioxide (CO2) and the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate ([bmim][BF4]) was studied experimentally. A synthetic method was used to measure its phase behavior. Bubble-point pressures of the

Thermodynamic promotion of carbon dioxide-clathrate hydrate formation by tetrahydrofuran, cyclopentane and their mixtures

DEFF Research Database (Denmark)

Herslund, Peter Jørgensen; Thomsen, Kaj; Abildskov, Jens

2013-01-01

Gas clathrate hydrate dissociation pressures are reported for mixtures of carbon dioxide, water and thermodynamic promoters forming structure II hydrates.Hydrate (H)-aqueous liquid (Lw)-vapour (V) equilibrium pressures for the ternary system composed of water, tetrahydrofuran (THF), and carbon....... It is shown that upon adding THF to the pure aqueous phase to form a 4mass percent solution, the equilibrium pressure of the formed hydrates may be lowered compared to the ternary system of water, cyclopentane and carbon dioxide. © 2013 Elsevier Ltd....... dioxide (CO2), with 5.0mole percent THF in the initial aqueous phase, are presented in the temperature range from 283.3K to 285.2K. At 283.3K, the three-phase equilibrium pressure is determined to be 0.61MPa (absolute pressure).Four-phase hydrate (H)-aqueous liquid (Lw)-organic liquid (La)-vapour (V...

Effect of high pressurized carbon dioxide on Escherichia coli ...

African Journals Online (AJOL)

Carbon dioxide at high pressure can retard microbial growth and sometimes kill microorganisms depending on values of applied pressure, temperature and exposure time. In this study the effect of high pressurised carbon dioxide (HPCD) on Escherichia coli was investigated. Culture of E. coli was subjected to high ...

Terpolymerization of ethylene, sulfur dioxide and carbon monoxide

Science.gov (United States)

Johnson, R.; Steinberg, M.

This invention relates to high molecular weight terpolymer of ethylene, sulfur dioxide and carbon monoxide stable to 280/sup 0/C and containing as little as 36 mo1% ethylene and about 41 to 51 mo1% sulfur dioxide, and to the method of producing said terpolymer by irradiation of a liquid and gaseous mixture of ethylene, sulfur dioxide and carbon monoxide by means of Co-60 gamma rays or an electron beam, at a temperature of about 10 to 50/sup 0/C, and at a pressure of about 140 to 680 atmospheres, to initiate polymerization.

Effects of fuel and forest conservation on future levels of atmospheric carbon dioxide.

Science.gov (United States)

Walker, J C; Kasting, J F

1992-01-01

We develop a numerical simulation of the global biogeochemical cycles of carbon that works over time scales extending from years to millions of years. The ocean is represented by warm and cold shallow water reservoirs, a thermocline reservoir, and deep Atlantic, Indian, and Pacific reservoirs. The atmosphere is characterized by a single carbon reservoir and the global biota by a single biomass reservoir. The simulation includes the rock cycle, distinguishing between shelf carbonate and pelagic carbonate precipitation, with distinct lysocline depths in the three deep ocean reservoirs. Dissolution of pelagic carbonates in response to decrease in lysocline depth is included. The simulation is tuned to reproduce the observed radiocarbon record resulting from atomic weapon testing. It is tuned also to reproduce the distribution of dissolved phosphate and total dissolved carbon between the ocean reservoirs as well as the carbon isotope ratios for both 13C and 14C in ocean and atmosphere. The simulation reproduces reasonably well the historical record of carbon dioxide partial pressure as well as the atmospheric isotope ratios for 13C and 14C over the last 200 yr as these have changed in response to fossil fuel burning and land use changes, principally forest clearance. The agreements between observation and calculation involves the assumption of a carbon dioxide fertilization effect in which the rate of production of biomass increases with increasing carbon dioxide partial pressure. At present the fertilization effect of increased carbon dioxide outweighs the effects of forest clearance, so the biota comprises an overall sink of atmospheric carbon dioxide sufficiently large to bring the budget approximately into balance. This simulation is used to examine the future evolution of carbon dioxide and its sensitivity to assumptions about the rate of fossil fuel burning and of forest clearance. Over times extending up to thousands of years, the results are insensitive to the

Design and experimental analysis of a carbon dioxide transcritical chiller for commercial refrigeration

International Nuclear Information System (INIS)

Cecchinato, Luca; Chiarello, Manuel; Corradi, Marco

2010-01-01

Carbon dioxide is an interesting solution for commercial refrigeration and in perspective for air-conditioning systems. In this paper a newly developed carbon dioxide transcritical air cooled chiller for refrigerating propylene glycol down to -8 o C supply temperature is described. The aim of the project was at optimising the cycle energy efficiency while assuring reliable operation and simple management of the unit. The carbon dioxide optimal pressure issue is addressed with an innovate system architecture and control logic. Using a flash tanks and two electronic valves, the optimal cycle upper pressure was maintained in transcritical operation mode. The managing of the valves allows the refrigeration machine efficiency improvement when the gas cooler inlet air allows subcritical working conditions. A simulation model of the chiller was developed and its results validated with experimental data. A measurement campaign was carried out, testing the chiller at external temperatures ranging from 18 to 35 o C, the unit energy efficiency ranging from 3.1 to 2.0.

Microbial production of multi-carbon chemicals and fuels from water and carbon dioxide using electric current

Science.gov (United States)

Lovley, Derek R.; Nevin, Kelly P.

2018-01-02

The invention provides systems and methods for generating organic compounds using carbon dioxide as a source of carbon and electrical current as an energy source. In one embodiment, a reaction cell is provided having a cathode electrode and an anode electrode that are connected to a source of electrical power, and which are separated by a permeable membrane. A biological film is provided on the cathode. The biological film comprises a bacterium that can accept electrons and that can convert carbon dioxide to a carbon-bearing compound and water in a cathode half-reaction. At the anode, water is decomposed to free molecular oxygen and solvated protons in an anode half-reaction. The half-reactions are driven by the application of electrical current from an external source. Compounds that have been produced include acetate, butanol, 2-oxobutyrate, propanol, ethanol, and formate.

Microbial production of multi-carbon chemicals and fuels from water and carbon dioxide using electric current

Energy Technology Data Exchange (ETDEWEB)

Lovley, Derek R; Nevin, Kelly

2015-11-03

The invention provides systems and methods for generating organic compounds using carbon dioxide as a source of carbon and electrical current as an energy source. In one embodiment, a reaction cell is provided having a cathode electrode and an anode electrode that are connected to a source of electrical power, and which are separated by a permeable membrane. A biological film is provided on the cathode. The biological film comprises a bacterium that can accept electrons and that can convert carbon dioxide to a carbon-bearing compound and water in a cathode half-reaction. At the anode, water is decomposed to free molecular oxygen and solvated protons in an anode half-reaction. The half-reactions are driven by the application of electrical current from an external source. Compounds that have been produced include acetate, butanol, 2-oxobutyrate, propanol, ethanol, and formate.

49 CFR 195.4 - Compatibility necessary for transportation of hazardous liquids or carbon dioxide.

Science.gov (United States)

2010-10-01

... hazardous liquids or carbon dioxide. 195.4 Section 195.4 Transportation Other Regulations Relating to... necessary for transportation of hazardous liquids or carbon dioxide. No person may transport any hazardous liquid or carbon dioxide unless the hazardous liquid or carbon dioxide is chemically compatible with both...

A carbon dioxide stripping model for mammalian cell culture in manufacturing scale bioreactors.

Science.gov (United States)

Xing, Zizhuo; Lewis, Amanda M; Borys, Michael C; Li, Zheng Jian

2017-06-01

Control of carbon dioxide within the optimum range is important in mammalian bioprocesses at the manufacturing scale in order to ensure robust cell growth, high protein yields, and consistent quality attributes. The majority of bioprocess development work is done in laboratory bioreactors, in which carbon dioxide levels are more easily controlled. Some challenges in carbon dioxide control can present themselves when cell culture processes are scaled up, because carbon dioxide accumulation is a common feature due to longer gas-residence time of mammalian cell culture in large scale bioreactors. A carbon dioxide stripping model can be used to better understand and optimize parameters that are critical to cell culture processes at the manufacturing scale. The prevailing carbon dioxide stripping models in literature depend on mass transfer coefficients and were applicable to cell culture processes with low cell density or at stationary/cell death phase. However, it was reported that gas bubbles are saturated with carbon dioxide before leaving the culture, which makes carbon dioxide stripping no longer depend on a mass transfer coefficient in the new generation cell culture processes characterized by longer exponential growth phase, higher peak viable cell densities, and higher specific production rate. Here, we present a new carbon dioxide stripping model for manufacturing scale bioreactors, which is independent of carbon dioxide mass transfer coefficient, but takes into account the gas-residence time and gas CO 2 saturation time. The model was verified by CHO cell culture processes with different peak viable cell densities (7 to 12 × 10 6  cells mL -1 ) for two products in 5,000-L and 25,000-L bioreactors. The model was also applied to a next generation cell culture process to optimize cell culture conditions and reduce carbon dioxide levels at manufacturing scale. The model provides a useful tool to understand and better control cell culture carbon dioxide

Carbon Dioxide Reduction Post-Processing Sub-System Development

Science.gov (United States)

Abney, Morgan B.; Miller, Lee A.; Greenwood, Zachary; Barton, Katherine

2012-01-01

The state-of-the-art Carbon Dioxide (CO2) Reduction Assembly (CRA) on the International Space Station (ISS) facilitates the recovery of oxygen from metabolic CO2. The CRA utilizes the Sabatier process to produce water with methane as a byproduct. The methane is currently vented overboard as a waste product. Because the CRA relies on hydrogen for oxygen recovery, the loss of methane ultimately results in a loss of oxygen. For missions beyond low earth orbit, it will prove essential to maximize oxygen recovery. For this purpose, NASA is exploring an integrated post-processor system to recover hydrogen from CRA methane. The post-processor, called a Plasma Pyrolysis Assembly (PPA) partially pyrolyzes methane to recover hydrogen with acetylene as a byproduct. In-flight operation of post-processor will require a Methane Purification Assembly (MePA) and an Acetylene Separation Assembly (ASepA). Recent efforts have focused on the design, fabrication, and testing of these components. The results and conclusions of these efforts will be discussed as well as future plans.

Multimodel Predictive System for Carbon Dioxide Solubility in Saline Formation Waters

Energy Technology Data Exchange (ETDEWEB)

Wang, Zan; Small, Mitchell J; Karamalidis, Athanasios K

2013-02-05

The prediction of carbon dioxide solubility in brine at conditions relevant to carbon sequestration (i.e., high temperature, pressure, and salt concentration (T-P-X)) is crucial when this technology is applied. Eleven mathematical models for predicting CO{sub 2} solubility in brine are compared and considered for inclusion in a multimodel predictive system. Model goodness of fit is evaluated over the temperature range 304–433 K, pressure range 74–500 bar, and salt concentration range 0–7 m (NaCl equivalent), using 173 published CO{sub 2} solubility measurements, particularly selected for those conditions. The performance of each model is assessed using various statistical methods, including the Akaike Information Criterion (AIC) and the Bayesian Information Criterion (BIC). Different models emerge as best fits for different subranges of the input conditions. A classification tree is generated using machine learning methods to predict the best-performing model under different T-P-X subranges, allowing development of a multimodel predictive system (MMoPS) that selects and applies the model expected to yield the most accurate CO{sub 2} solubility prediction. Statistical analysis of the MMoPS predictions, including a stratified 5-fold cross validation, shows that MMoPS outperforms each individual model and increases the overall accuracy of CO{sub 2} solubility prediction across the range of T-P-X conditions likely to be encountered in carbon sequestration applications.

Calcium and chemical looping technology for power generation and carbon dioxide (CO2) capture solid oxygen- and CO2-carriers

CERN Document Server

Fennell, Paul

2015-01-01

Calcium and Chemical Looping Technology for Power Generation and Carbon Dioxide (CO2) Capture reviews the fundamental principles, systems, oxygen carriers, and carbon dioxide carriers relevant to chemical looping and combustion. Chapters review the market development, economics, and deployment of these systems, also providing detailed information on the variety of materials and processes that will help to shape the future of CO2 capture ready power plants. Reviews the fundamental principles, systems, oxygen carriers, and carbon dioxide carriers relevant to calcium and chemical loopingProvi

Somewhere beyond the sea? The oceanic - carbon dioxide - reactions

Science.gov (United States)

Meisinger, Philipp; Wittlich, Christian

2014-05-01

In correlation to climate change and CO2 emission different campaigns highlight the importance of forests and trees to regulate the concentration of carbon dioxide in the earths' atmosphere. Seeing millions of square miles of rainforest cut down every day, this is truly a valid point. Nevertheless, we often tend to forget what scientists like Spokes try to raise awareness for: The oceans - and foremost deep sea sections - resemble the second biggest deposit of carbon dioxide. Here carbon is mainly found in form of carbonate and hydrogen carbonate. The carbonates are needed by corals and other sea organisms to maintain their skeletal structure and thereby to remain vital. To raise awareness for the protection of this fragile ecosystem in schools is part of our approach. Awareness is achieved best through understanding. Therefore, our approach is a hands-on activity that aims at showing students how the carbon dioxide absorption changes in relation to the water temperature - in times of global warming a truly sensitive topic. The students use standard syringes filled with water (25 ml) at different temperatures (i.e. 10°C, 20°C, 40°C). Through a connector students inject carbon dioxide (25ml) into the different samples. After a fixed period of time, students can read of the remaining amount of carbon dioxide in relation to the given water temperature. Just as with every scientific project, students need to closely monitor their experiments and alter their setups (e.g. water temperature or acidity) according to their initial planning. A digital template (Excel-based) supports the analysis of students' experiments. Overview: What: hands-on, minds -on activity using standard syringes to exemplify carbon dioxide absorption in relation to the water temperature (Le Chatelier's principle) For whom: adjustable from German form 11-13 (age: 16-19 years) Time: depending on the prior knowledge 45-60 min. Sources (extract): Spokes, L.: Wie Ozeane CO2 aufnehmen. Environmental

Industrial structural transformation and carbon dioxide emissions in China

International Nuclear Information System (INIS)

Zhou, Xiaoyan; Zhang, Jie; Li, Junpeng

2013-01-01

Using provincial panel data from the period 1995–2009 to analyze the relationship between the industrial structural transformation and carbon dioxide emissions in China, we find that the first-order lag of industrial structural adjustment effectively reduced the emissions; technical progress itself did not reduce the emissions, but indirectly led to decreasing emissions through the upgrading and optimization of industrial structure. Foreign direct investment and intervention by local governments reduced carbon dioxide emissions, but urbanization significantly increased the emissions. Thus, industrial structural adjustment is an important component of the development of a low-carbon economy. In the context of industrial structural transformation, an effective way to reduce a region’s carbon dioxide emissions is to promote the upgrading and optimization of industrial structure through technical progress. Tighter environmental access policies, selective utilization of foreign direct investment, and improvements in energy efficiency can help to reduce carbon dioxide emissions. - Highlights: ► Relationship between the transformation of industrial structure and CO 2 emissions in China. ► Dynamic panel data model. ► Industrial structural adjustments can effectively reduce current CO 2 emissions. ► Technical progress leads to decreasing CO 2 emissions through upgrading of industrial structure

Carbon dioxide stripping in aquaculture -- part II: development of gas transfer models

Science.gov (United States)

Colt, John; Watten, Barnaby; Pfeiffer, Tim

2012-01-01

The basic mass transfer equation for gases such as oxygen and carbon dioxide can be derived from integration of the driving force equation. Because of the physical characteristics of the gas transfer processes, slightly different models are used for aerators tested under the non steady-state procedures, than for packed columns, or weirs. It is suggested that the standard condition for carbon dioxide should be 20 °C, 1 atm, CCO2=20 mg/kg, and XCO2=0.000285. The selection of the standard condition for carbon dioxide based on a fixed mole fraction ensures that standardized carbon dioxide transfer rates will be comparable even though the value of C*CO2 in the atmosphere is increasing with time. The computation of mass transfer for carbon dioxide is complicated by the impact of water depth and gas phase enrichment on the saturation concentration within the unit, although the importance of either factor depends strongly on the specific type of aerator. For some types of aerators, the most accurate gas phase model remains to be determined for carbon dioxide. The assumption that carbon dioxide can be treated as a non-reactive gas in packed columns may apply for cold acidic waters but not for warm alkaline waters.

Silver birch and climate change: variable growth and carbon allocation responses to elevated concentrations of carbon dioxide and ozone

International Nuclear Information System (INIS)

Riikonen, J.; Holopainen, T.; Oksanen, E.; Lindsberg, M-M.; Lappi, J.; Peltonen, P.; Vapaavuori, E.

2004-01-01

The effects of elevated concentrations of carbon dioxide and ozone were studied on growth, biomass allocation and leaf area of field-grown ozone-tolerant (Clone 4) and ozone-sensitive (Clone 80) European silver birch trees. Seven-year old trees of both types were exposed for three years to outside and chamber control, (1) twice ambient ozone, (2) twice ambient carbon dioxide, and (3) twice ambient carbon dioxide and twice ambient ozone. No effect on biomass allocation was observed when results of the two clones were analyzed together. Total leaf area showed an increase, and leaf abscission appeared delayed in response to elevated carbon dioxide. Elevated ozone caused the dry mass of roots, branches and mean leaf size to decrease, and autumnal leaf abscission occurred earlier than usual in both clones. In general. the effects of elevated ozone were small, however, the interaction between elevated carbon dioxide and elevated oxygen were significant. When results from the two clones were analyzed separately, stem diameter, volume growth and total biomass of Clone 80 increased when exposed to elevated concentrations of carbon dioxide; elevated concentrations of ozone appeared to have no effect. In Clone 4 elevated ozone caused significant decrease in root and branch biomass, but the effects of elevated carbon dioxide were minimal. Responses to elevated ozone exposure were observed only under ambient carbon dioxide conditions. This response is believed to reflect the greater quantity of carbohydrates available for detoxification and repair under elevated carbon dioxide conditions. Alternatively, the response may be due to decreased stomatal conductance, thus decreased ozone uptake under elevated carbon dioxide conditions. 45 refs., 6 tabs., 4 figs

Increasing carbon dioxide and the response of plants to this challenge

International Nuclear Information System (INIS)

Bazzaz, F.A.; Fajer, E.D.

1992-01-01

Discussed are the effects that increasing carbon dioxide concentrations in the air tend to have on the various types of plant. In the so-called C 3 group of plants globally elevated carbon dioxide levels may lead to increases in the rate of photosynthesis, even though these often appear to be only of a transient nature. The C 4 group of plants, however, clearly are at a disadvantage here. The attendant agricultural problems and resulting dangers to complete ecosystems including animals are described. Mention is also made of the possibility of using plants as carbon dioxide repositories. The urgent need for measures leading to a reduction of carbon dioxide emissions is strongly pointed out. (MG) [de

High-energy, short-pulse, carbon-dioxide lasers

International Nuclear Information System (INIS)

Fenstermacher, C.A.

1979-01-01

Lasers for fusion application represent a special class of short-pulse generators; not only must they generate extremely short temporal pulses of high quality, but they must do this at ultra-high powers and satisfy other stringent requirements by this application. This paper presents the status of the research and development of carbon-dioxide laser systems at the Los Alamos Scientific Laboratory, vis-a-vis the fusion requirements

Analysis of energy consumption and carbon dioxide emissions in ceramic tile manufacture

International Nuclear Information System (INIS)

Monfort, E.; Mezquita, A.; Granel, R.; Vaquer, E.; Escrig, A.; Miralles, A.; Zaera, V.

2010-01-01

The ceramic tile manufacturing process is energy intensive since it contains several stages in which the product is subject to thermal treatment. The thermal energy used in the process is usually obtained by combustion of natural gas, which is a fossil fuel whose oxidation produces emissions of carbon dioxide, a greenhouse gas. Energy costs account for 15% of the average direct manufacturing costs, and are strongly influenced by the price of natural gas, which has increased significantly in the last few years. Carbon dioxide emissions are internationally monitored and controlled in the frame of the Kyoto Protocol. Applicable Spanish law is based on the European Directive on emissions trading, and the assignment of emissions rights is based on historical values in the sectors involved. Legislation is scheduled to change in 2013, and the resulting changes will directly affect the Spanish ceramic tile manufacturing industry, since many facilities will become part of the emissions trading system. The purpose of this study is to determine current thermal energy consumption and carbon dioxide emissions in the ceramic tile manufacturing process. A comprehensive sectoral study has been carried out for this purpose on several levels: the first analyses energy consumption and carbon dioxide emissions in the entire industry; the second determines energy consumption and carbon dioxide emissions in industrial facilities over a long period of time (several months); while the third level breaks down these values, determining energy consumption and emissions in terms of the product made and the manufacturing stage. (Author) 8 refs.

Carbon dioxide in magmas and implications for hydrothermal systems

Science.gov (United States)

Lowenstern, J. B.

2001-01-01

This review focuses on the solubility, origin, abundance, and degassing of carbon dioxide (CO2) in magma-hydrothermal systems, with applications for those workers interested in intrusion-related deposits of gold and other metals. The solubility of CO2 increases with pressure and magma alkalinity. Its solubility is low relative to that of H2O, so that fluids exsolved deep in the crust tend to have high CO2/H2O compared with fluids evolved closer to the surface. Similarly, CO2/H2O will typically decrease during progressive decompression- or crystallization-induced degassing. The temperature dependence of solubility is a function of the speciation of CO2, which dissolves in molecular form in rhyolites (retrograde temperature solubility), but exists as dissolved carbonate groups in basalts (prograde). Magnesite and dolomite are stable under a relatively wide range of mantle conditions, but melt just above the solidus, thereby contributing CO2 to mantle magmas. Graphite, diamond, and a free CO2-bearing fluid may be the primary carbon-bearing phases in other mantle source regions. Growing evidence suggests that most CO2 is contributed to arc magmas via recycling of subducted oceanic crust and its overlying sediment blanket. Additional carbon can be added to magmas during magma-wallrock interactions in the crust. Studies of fluid and melt inclusions from intrusive and extrusive igneous rocks yield ample evidence that many magmas are vapor saturated as deep as the mid crust (10-15 km) and that CO2 is an appreciable part of the exsolved vapor. Such is the case in both basaltic and some silicic magmas. Under most conditions, the presence of a CO2-bearing vapor does not hinder, and in fact may promote, the ascent and eruption of the host magma. Carbonic fluids are poorly miscible with aqueous fluids, particularly at high temperature and low pressure, so that the presence of CO2 can induce immiscibility both within the magmatic volatile phase and in hydrothermal systems

Developing a molecular platform for potential carbon dioxide fixing

DEFF Research Database (Denmark)

Mikkelsen, Mette; Jørgensen, Mikkel; Krebs, Frederik C

2010-01-01

This paper presents an attempt to develop a new system for fixing carbon dioxide from the atmosphere. The proposed molecular system has been designed to have the capacity to spontaneously bind CO2 from the atmosphere with high affinity. The molecular system is furthermore designed to have...... the ability to liberate CO2 at a later stage in the process, i.e., in a separate compartment. The liberated CO2 presents a carbon neutral way of obtaining pure CO2. The proposed molecular system is based on a small stable organic molecule that potentially have two forms: one without bound CO2 and one...

Solid carbon dioxide to promote the extraction of extra-virgin olive oil

Energy Technology Data Exchange (ETDEWEB)

Zinnai, A.; Venturi, F.; Quartacci, V.F.; Sanmartin, C.; Favati, F.; Andrich, G.

2016-07-01

The use of solid carbon dioxide (dry ice) as a cryogen is widespread in the food industry to produce high quality wines, rich in color and perfumes. The direct addition of carbon dioxide to olives in the solid state before milling represents a fundamental step which characterizes this innovative extraction system. At room temperature conditions solid carbon dioxide evolves directly into the air phase (sublimation), and the direct contact between the cryogen and the olives induces a partial solidification of the cellular water inside the fruits. Since the volume occupied by water in the solid state is higher than that in the liquid state, the ice crystals formed are incompatible with the cellular structure and induce the collapse of the cells, besides promoting the diffusion of the cellular substances in the extracted oil, which is thus enriched with cellular metabolites characterized by a high nutraceutical value. Furthermore, a layer of CO2 remains over the olive paste to preserve it from oxidative degradation. The addition of solid carbon dioxide to processed olives induced a statistically significant increase in oil yield and promoted the accumulation of tocopherols in the lipid phase, whereas a not significant increase in the phenolic fraction of the oil occurred. (Author)

Carbon Dioxide Control System for a Mars Space Suit Life Support System

Science.gov (United States)

Alptekin, Gokhan; Jayaraman, Ambalavanan; Copeland, Robert; Parker, Amanda; Paul, Heather L.

2011-01-01

Carbon dioxide (CO2) control during Extravehicular Activities (EVAs) on Mars will be challenging. Lithium hydroxide (LiOH) canisters have impractical logistics penalties, and regenerable metal oxide (MetOx) canisters weigh too much. Cycling bed systems and permeable membranes that are regenerable in space vacuum cannot vent on Mars due to the high partial pressure of CO2 in the atmosphere. Although sweep gas regeneration is under investigation, the feasibility, logistics penalties, and failure modes associated with this technique have not been fully determined. TDA Research, Inc. is developing a durable, high-capacity regenerable adsorbent that can remove CO2 from the space suit ventilation loop. The system design allows sorbent regeneration at or above 6 torr, eliminating the potential for Martian atmosphere to leak into the regeneration bed and into the ventilation loop. Regeneration during EVA minimizes the amount of consumables to be brought from Earth and makes the mission more affordable, while providing great operational flexibility during EVA. The feasibility of the concept has been demonstrated in a series of bench-scale experiments and a preliminary system analysis. This paper presents the latest results from these sorbent and system development efforts.

High-resolution carbon dioxide concentration record 650,000-800,000 years before present

Energy Technology Data Exchange (ETDEWEB)

Luthi, D; Bereiter, B; Blunier, T; Siegenthaler, U; Kawamura, K; Stocker, T F [Climate and Environm. Physics, Physics Inst., Univ. Bern, CH-3012 Bern, (Switzerland); Luthi, D; Bereiter, B; Blunier, T; Siegenthaler, U; Kawamura, K; Stocker, T F [Oeschger Centre for Climate Change Research, Univ. Bern, CH-3012 Bern, (Switzerland); Le Floch, M; Barnola, J M; Raynaud, D [LGGE, CNRS-Univ. Grenoble 1, F-38402 Saint Martin d' Heres, (France); Jouzel, J [Inst. Pierre Simon Laplace, LSCE, CEA-CNRS-Universite Versailles-Saint Quentin, CEA Saclay, F-91191 Gif sur Yvette (France); Fischer, H [Alfred Wegener Inst. for Polar and Maine Research, D-27568 Bremerhaven, (Germany)

2008-07-01

Changes in past atmospheric carbon dioxide concentrations can be determined by measuring the composition of air trapped in ice cores from Antarctica. So far, the Antarctic Vostok and EPICA Dome C ice cores have provided a composite record of atmospheric carbon dioxide levels over the past 650,000 years. Here we present results of the lowest 200 m of the Dome C ice core, extending the record of atmospheric carbon dioxide concentration by two complete glacial cycles to 800,000 yr before present. From previously published data and the present work, we find that atmospheric carbon dioxide is strongly correlated with Antarctic temperature throughout eight glacial cycles but with significantly lower concentrations between 650,000 and 750,000 yr before present. Carbon dioxide levels are below 180 parts per million by volume (p.p.m.v.) for a period of 3,000 yr during Marine Isotope Stage 16, possibly reflecting more pronounced oceanic carbon storage. We report the lowest carbon dioxide concentration measured in an ice core, which extends the pre-industrial range of carbon dioxide concentrations during the late Quaternary by about 10 p.p.m.v. to 172-300 p.p.m.v. (authors)

Driving factors behind carbon dioxide emissions in China: A modified production-theoretical decomposition analysis

International Nuclear Information System (INIS)

Wang, Qunwei; Chiu, Yung-Ho; Chiu, Ching-Ren

2015-01-01

Research on the driving factors behind carbon dioxide emission changes in China can inform better carbon emission reduction policies and help develop a low-carbon economy. As one of important methods, production-theoretical decomposition analysis (PDA) has been widely used to understand these driving factors. To avoid the infeasibility issue in solving the linear programming, this study proposed a modified PDA approach to decompose carbon dioxide emission changes into seven drivers. Using 2005–2010 data, the study found that economic development was the largest factor of increasing carbon dioxide emissions. The second factor was energy structure (reflecting potential carbon), and the third factor was low energy efficiency. Technological advances, energy intensity reductions, and carbon dioxide emission efficiency improvements were the negative driving factors reducing carbon dioxide emission growth rates. Carbon dioxide emissions and driving factors varied significantly across east, central and west China. - Highlights: • A modified PDA used to decompose carbon dioxide emission changes into seven drivers. • Two models were proposed to ameliorate the infeasible occasions. • Economic development was the largest factor of increasing CO_2 emissions in China.

Understanding how individuals perceive carbon dioxide. Implications for acceptance of carbon dioxide capture and storage

Energy Technology Data Exchange (ETDEWEB)

Itaoka, K.; Saito, A. [Mizuho Information and Research Institute, Tokyo (Japan); Paukovic, M.; De Best-Waldhober, M. [ECN Policy Studies, Petten (Netherlands); Dowd, A.M.; Jeanneret, T.; Ashworth, P.; James, M. [The Global CCS Institute, Canberra (Australia)

2012-06-15

Carbon dioxide capture and storage (CCS) presents one potential technological solution for mitigating the atmospheric emission of carbon dioxide sources. However, CCS is a relatively new technology with associated uncertainties and perceived risks. For this reason, a growing body of research now focuses on public perceptions and potential for societal acceptance of CCS technology. Almost all explanations of CCS technology make reference to carbon dioxide, with an assumption that the general public understands CO2. It has become apparent that the general public’s knowledge and understanding of CO2’s properties influences how they engage with CO2 emitting industries and CCS technologies. However, surprisingly little research has investigated public perceptions, knowledge, and understanding of CO2. This investigation attempts to fill that gap. This report describes an investigation of how citizens of three countries (Japan, Australia, and the Netherlands) perceive CO2. Furthermore, it attempts to relate individual perceptions of CO2 to perceptions of CCS, and to determine how information provision about the underlying properties and characteristics of CO2 influences individual attitudes towards low carbon energy options, particularly CCS. In brief, the research had four ultimate aims. It aimed to: Explore the public’s knowledge and understanding of the properties of CO2; Examine the influence of that knowledge on their perceptions of CO2 and CCS; Investigate how information provision about the underlying properties and characteristics of CO2 influences individual attitudes towards CCS; and Identify if any differences between countries exist in relation to values and beliefs, knowledge of CO2’s properties, and CCS perceptions.

Extraction of Carbon Dioxide and Hydrogen from Seawater and Hydrocarbon Production Therefrom

Science.gov (United States)

2016-04-05

acidification of seawater by subjecting the seawater to an ion exchange reaction to exchange H.sup. ions for Na.sup. ions. Carbon dioxide may be...extracted from the acidified seawater. Optionally, the ion exchange reaction can be conducted under conditions which produce hydrogen as well as carbon dioxide . The carbon dioxide and hydrogen may be used to produce hydrocarbons.

CARBON DIOXIDE FIXATION.

Energy Technology Data Exchange (ETDEWEB)

FUJITA,E.

2000-01-12

Solar carbon dioxide fixation offers the possibility of a renewable source of chemicals and fuels in the future. Its realization rests on future advances in the efficiency of solar energy collection and development of suitable catalysts for CO{sub 2} conversion. Recent achievements in the efficiency of solar energy conversion and in catalysis suggest that this approach holds a great deal of promise for contributing to future needs for fuels and chemicals.

Carbon dioxide and climate

Energy Technology Data Exchange (ETDEWEB)

1990-10-01

Scientific and public interest in greenhouse gases, climate warming, and global change virtually exploded in 1988. The Department's focused research on atmospheric CO{sub 2} contributed sound and timely scientific information to the many questions produced by the groundswell of interest and concern. Research projects summarized in this document provided the data base that made timely responses possible, and the contributions from participating scientists are genuinely appreciated. In the past year, the core CO{sub 2} research has continued to improve the scientific knowledge needed to project future atmospheric CO{sub 2} concentrations, to estimate climate sensitivity, and to assess the responses of vegetation to rising concentrations of CO{sub 2} and to climate change. The Carbon Dioxide Research Program's goal is to develop sound scientific information for policy formulation and governmental action in response to changes of atmospheric CO{sub 2}. The Program Summary describes projects funded by the Carbon Dioxide Research Program during FY 1990 and gives a brief overview of objectives, organization, and accomplishments.

Internal Active Thermal Control System (IATCS) Sodium Bicarbonate/Carbonate Buffer in an Open Aqueous Carbon Dioxide System and Corollary Electrochemical/Chemical Reactions Relative to System pH Changes

Science.gov (United States)

Stegman, Thomas W.; Wilson, Mark E.; Glasscock, Brad; Holt, Mike

2014-01-01

The International Space Station (ISS) Internal Active Thermal Control System (IATCS) experienced a number of chemical changes driven by system absorption of CO2 which altered the coolant’s pH. The natural effects of the decrease in pH from approximately 9.2 to less than 8.4 had immediate consequences on system corrosion rates and corrosion product interactions with specified coolant constituents. The alkalinity of the system was increased through the development and implementation of a carbonate/bicarbonate buffer that would increase coolant pH to 9.0 – 10.0 and maintain pH above 9.0 in the presence of ISS cabin concentrations of CO2 up to twenty times higher than ground concentrations. This paper defines how a carbonate/bicarbonate buffer works in an open carbon dioxide system and summarizes the analyses performed on the buffer for safe and effective application in the on-orbit system. The importance of the relationship between the cabin environment and the IATCS is demonstrated as the dominant factor in understanding the system chemistry and pH trends before and after addition of the carbonate/bicarbonate buffer. The paper also documents the corollary electrochemical and chemical reactions the system has experienced and the rationale for remediation of these effects with the addition of the carbonate/bicarbonate buffer.

Underground coal gasification with integrated carbon dioxide mitigation supports Bulgaria's low carbon energy supply

Science.gov (United States)

Nakaten, Natalie; Kempka, Thomas; Azzam, Rafig

2013-04-01

Underground coal gasification allows for the utilisation of coal reserves that are economically not exploitable due to complex geological boundary conditions. The present study investigates underground coal gasification as a potential economic approach for conversion of deep-seated coals into a high-calorific synthesis gas to support the Bulgarian energy system. Coupling of underground coal gasification providing synthesis gas to fuel a combined cycle gas turbine with carbon capture and storage is considered to provide substantial benefits in supporting the Bulgarian energy system with a competitive source of energy. In addition, underground voids originating from coal consumption increase the potential for geological storage of carbon dioxide resulting from the coupled process of energy production. Cost-effectiveness, energy consumption and carbon dioxide emissions of this coupled process are investigated by application of a techno-economic model specifically developed for that purpose. Capital (CAPEX) and operational expenditure (OPEX) are derived from calculations using six dynamic sub-models describing the entire coupled process and aiming at determination of the levelised costs of electricity generation (COE). The techno-economic model is embedded into an energy system-modelling framework to determine the potential integration of the introduced low carbon energy production technology into the Bulgarian energy system and its competitiveness at the energy market. For that purpose, boundary conditions resulting from geological settings as well as those determined by the Bulgarian energy system and its foreseeable future development have to be considered in the energy system-modelling framework. These tasks comprise integration of the present infrastructure of the Bulgarian energy production and transport system. Hereby, the knowledge on the existing power plant stock and its scheduled future development are of uttermost importance, since only phasing-out power

Carbon dioxide utilization in a microalga-based biorefinery: Efficiency of carbon removal and economic performance under carbon taxation.

Science.gov (United States)

Wiesberg, Igor Lapenda; Brigagão, George Victor; de Medeiros, José Luiz; de Queiroz Fernandes Araújo, Ofélia

2017-12-01

Coal-fired power plants are major stationary sources of carbon dioxide and environmental constraints demand technologies for abatement. Although Carbon Capture and Storage is the most mature route, it poses severe economic penalty to power generation. Alternatively, this penalty is potentially reduced by Carbon Capture and Utilization, which converts carbon dioxide to valuable products, monetizing it. This work evaluates a route consisting of carbon dioxide bio-capture by Chlorella pyrenoidosa and use of the resulting biomass as feedstock to a microalgae-based biorefinery; Carbon Capture and Storage route is evaluated as a reference technology. The integrated arrangement comprises: (a) carbon dioxide biocapture in a photobioreactor, (b) oil extraction from part of the produced biomass, (b) gasification of remaining biomass to obtain bio-syngas, and (c) conversion of bio-syngas to methanol. Calculation of capital and operational expenditures are estimated based on mass and energy balances obtained by process simulation for both routes (Carbon Capture and Storage and the biorefinery). Capital expenditure for the biorefinery is higher by a factor of 6.7, while operational expenditure is lower by a factor of 0.45 and revenues occur only for this route, with a ratio revenue/operational expenditure of 1.6. The photobioreactor is responsible for one fifth of the biorefinery capital expenditure, with footprint of about 1000 ha, posing the most significant barrier for technical and economic feasibility of the proposed biorefinery. The Biorefinery and Carbon Capture and Storage routes show carbon dioxide capture efficiency of 73% and 48%, respectively, with capture cost of 139$/t and 304$/t. Additionally, the biorefinery has superior performance in all evaluated metrics of environmental impacts. Copyright © 2017 Elsevier Ltd. All rights reserved.

Investigation of the adsorption of water vapor and carbon dioxide by KA zeolite

International Nuclear Information System (INIS)

Khanitonov, V.P.; Shtein, A.S.

1984-01-01

According to the present data, KA zeolite, which can adsorb only water vapor, helium, and hydrogen, has the greatest selectivity in drying. The feasibility of using this zeolite in devices for selective drying of gases used in gas-analysis systems was studied. The results of the experiments were approximated by the thermal equation of the theory of bulk filling of micropores. The limiting value of the adsorption depends on the temperature, and it can be calculated according to the density of the adsorbed phase and the adsorption volume. The critical diameters of the water and carbon dioxide molecules are close to the dimensions of the KA-zeolite pores, something that determines the activated nature of the adsorption of these substances. Experiments on coadsorption of water vapor and carbon dioxide by a fixed bed of KA-zeolite under dynamic conditions showed that the adsorption of these substances has a frontal nature. The time of the protective action of the layer of zeolite during adsorption af water vapor exceeded by more than an order the time of the protective action during adsorption of carbon dioxide. The results showed that this adsorbent can be used for selective drying of gas mixtures containing carbon dioxide in batch-operation devices. Beforehand, the adsorbent should be regenerated with respect to moisture, and then it should be saturated with carbon dioxide by blowing the adsorbent with a gas mixture of the working composition until the equilibrium state is reached

Microporous metal-organic framework with potential for carbon dioxide capture at ambient conditions

NARCIS (Netherlands)

Xiang, S.C.; He, Y.; Zhang, Z.; Wu, H.; Zhou, W.; Krishna, R.; Chen, B.

2012-01-01

Carbon dioxide capture and separation are important industrial processes that allow the use of carbon dioxide for the production of a range of chemical products and materials, and to minimize the effects of carbon dioxide emission. Porous metal-organic frameworks are promising materials to achieve

Interaction of titanium and vanadium with carbon dioxide under heating

International Nuclear Information System (INIS)

Vlasyuk, R.Z.; Kurovskij, V.Ya.; Lyapunov, V.P.; Radomysel'skij, I.D.

1986-01-01

The methods of gravitmetric and X-ray phase analysis as well as analysis of composition of gases in the heating chamber have been used to investigate the mechanism of titanium and vanadium interaction with carbon dioxide in the 300-1000 deg C temperature range. The analogy of mechanisms of the interaction of titanium and vanadium with carbon dioxide in oxides production on the metal surface with subsequent carbidizing treatment at temperatures above 800 deg C is shown. Temperature limits of material operation on the base of titanium or vanadium in carbon dioxide must not exceed 400 or 600 deg C, respectively

Evaluation of process costs for small-scale carbon dioxide removal from natural gas. Topical report, September 1989-December 1989

International Nuclear Information System (INIS)

Changela, M.K.; Reading, G.J.; Echterhoff, L.W.

1991-08-01

The report establishes the cost of producing pipeline quality gas on a small scale from high carbon dioxide subquality natural gas. Two processing technologies are evaluated: conventional diethanolamine (DEA) absorption and membrane separation. Comparison of the established costs shows both capital and operating cost advantages for small-scale membrane applications. Membranes offer higher cost savings at low feed flow rates and high carbon dioxide feed contents. Membranes are produced in modules, thus they do not exhibit economies of scale. This works to their advantage for removing carbon dioxide on a small scale. Processing costs for amine systems are more sensitive to economies of scale, and thus decrease more rapidly than for membranes at higher feed flow rates. The report shows that membranes have a definite market niche within the natural gas processing arena. For economic reasons, membranes will likely become the technology of choice for small-scale systems that treat high carbon dioxide content natural gas streams. However, amines will continue to service large-scale systems and applications where deep carbon dioxide removal is required. A related report (GRI Report No. GRI-91/0093 entitled, 'Technical Evaluation of Hybrid Membrane/DEA Modeling') shows that hybrid systems, the integration of membranes and amines, also offer the potential to lower processing costs

Investigations into the post-natal development of demethylating enzyme systems by determination of carbon dioxide 14 in the air exhaled by mice after applications of carbon 14 dimethyl amino-antipyrine

International Nuclear Information System (INIS)

Schmidt, H.

1982-01-01

Albino mice were subcutaneously injected with carbon 14 dimethyl aminopyrines, the methyl group of which can be metabolised in the organism into carbon dioxide 14. The following results were obtained: In the carbon dioxide 14 exhalation of neonate, young and adult animals after administration of carbon 14 aminopyrine, distinct differences were noted. The maximum of elimination via the lungs occurs after 20-30 minutes in grown-up mice, in neonates or young animals distinctly later (60-90 min). The carbon dioxide 14 exhalation was also measured after additional subcutaneous application of methrotrexate. In mice aged 8 and 10 days a distinct decrease in carbon dioxide 14 exhalation was found. By contrast, a rise in carbon dioxide 14 exhaled was found in mice aged 2 days. The orientating experiments with folic acid and carbon 14 dimethyl aminopyrine show that leucovorin leads to a distinct increase in carbon dioxide 14 exhalation during the first 30 minutes. As a cause of the different degrees of stimulation respectively inhibition of demethylation, different biochemical ways of formaldehyde formation are pointed out. One of these probably includes the folate-dependent reaction. (orig./MG) [de

A dynamic state-level analysis of carbon dioxide emissions in the United States

International Nuclear Information System (INIS)

Roach, Travis

2013-01-01

As climate change and the regulation of carbon dioxide emissions play an increasingly important role in the global policy debate, careful consideration of the state-level determinants driving emissions must be considered. The importance of state-level determinants in the transmission of carbon dioxide matters especially for a country that differs from coast to coast in energy use and industry makeup like the United States. To add to the policy debate this paper estimates two models that account for the dynamic nature of emissions of carbon dioxide emissions at the state-level from 1980–2010 while taking account of scale, technique, and composition effects. When stochastic trends are taken account of, an environmental Kuznets curve relationship with a feasible turning point is found for carbon dioxide emissions. - Highlights: • State-level analysis of carbon dioxide emissions. • Dynamic panel estimation to account for time series properties. • Feasible environmental Kuznets curve for carbon dioxide emissions. • Implications for state environmental policy discussed

Reliability and Maintainability Analysis for the Amine Swingbed Carbon Dioxide Removal System

Science.gov (United States)

Dunbar, Tyler

2016-01-01

I have performed a reliability & maintainability analysis for the Amine Swingbed payload system. The Amine Swingbed is a carbon dioxide removal technology that has gone through 2,400 hours of International Space Station on-orbit use between 2013 and 2016. While the Amine Swingbed is currently an experimental payload system, the Amine Swingbed may be converted to system hardware. If the Amine Swingbed becomes system hardware, it will supplement the Carbon Dioxide Removal Assembly (CDRA) as the primary CO2 removal technology on the International Space Station. NASA is also considering using the Amine Swingbed as the primary carbon dioxide removal technology for future extravehicular mobility units and for the Orion, which will be used for the Asteroid Redirect and Journey to Mars missions. The qualitative component of the reliability and maintainability analysis is a Failure Modes and Effects Analysis (FMEA). In the FMEA, I have investigated how individual components in the Amine Swingbed may fail, and what the worst case scenario is should a failure occur. The significant failure effects are the loss of ability to remove carbon dioxide, the formation of ammonia due to chemical degradation of the amine, and loss of atmosphere because the Amine Swingbed uses the vacuum of space to regenerate the Amine Swingbed. In the quantitative component of the reliability and maintainability analysis, I have assumed a constant failure rate for both electronic and nonelectronic parts. Using this data, I have created a Poisson distribution to predict the failure rate of the Amine Swingbed as a whole. I have determined a mean time to failure for the Amine Swingbed to be approximately 1,400 hours. The observed mean time to failure for the system is between 600 and 1,200 hours. This range includes initial testing of the Amine Swingbed, as well as software faults that are understood to be non-critical. If many of the commercial parts were switched to military-grade parts, the expected

Development of Carbon Dioxide Removal Systems for Advanced Exploration Systems 2014-2015

Science.gov (United States)

Knox, James C.; Coker, Robert; Huff, Timothy L.; Gatens, Robyn; Miller, Lee A.; Stanley, Christine

2015-01-01

A long-term goal for NASA is to enable crewed missions to Mars: first to the vicinity of Mars, and then to the Mars surface. These missions present new challenges for all aspects of spacecraft design in comparison with the International Space Station, as resupply is unavailable in the transit phase, and early return is not possible. Additionally, mass, power, and volume must be minimized for all phases to reduce propulsion needs. Mass reduction is particularly crucial for Mars surface landing and liftoff due to the challenges inherent in these operations for even much smaller payloads. In this paper we describe current and planned developments in the area of carbon dioxide removal to support future crewed Mars missions. Activities are also described that apply to both the resolution of anomalies observed in the ISS CDRA and the design of life support systems for future missions.

Development of Carbon Dioxide Removal Systems for Advanced Exploration Systems 2015-2016

Science.gov (United States)

Knox, James; Coker, Robert; Huff, Tim; Miller, Lee

2016-01-01

A long-term goal for NASA is to enable crewed missions to Mars: first to the vicinity of Mars, and then to the Mars surface. These missions present new challenges for all aspects of spacecraft design in comparison with the International Space Station, as resupply is unavailable in the transit phase, and early return is not possible. Additionally, mass, power, and volume must be minimized for all phases to reduce propulsion needs. Mass reduction is particularly crucial for Mars surface landing and liftoff due to the challenges inherent in these operations for even much smaller payloads. In this paper we describe current and planned developments in the area of carbon dioxide removal to support future crewed Mars missions. Activities are also described that apply to both the resolution of anomalies observed in the ISS CDRA and the design of life support systems for future missions.

Development of a prototype regeneration carbon dioxide absorber. [for use in EVA conditions

Science.gov (United States)

Patel, P. S.; Baker, B. S.

1977-01-01

A prototype regenerable carbon dioxide absorber was developed to maintain the environmental quality of the portable life support system. The absorber works on the alkali metal carbonate-bicarbonate solid-gas reaction to remove carbon dioxide from the atmosphere. The prototype sorber module was designed, fabricated, and tested at simulated extravehicular activity conditions to arrive at optimum design. The unit maintains sorber outlet concentration below 5 mm Hg. An optimization study was made with respect to heat transfer, temperature control, sorbent utilization, sorber life and regenerability, and final size of the module. Important parameters influencing the capacity of the final absorber unit were identified and recommendations for improvement were made.

Fischer-Tropsch synthesis in supercritical phase carbon dioxide: Recycle rates

Science.gov (United States)

Soti, Madhav

With increasing oil prices and attention towards the reduction of anthropogenic CO2, the use of supercritical carbon dioxide for Fischer Tropsch Synthesis (FTS) is showing promise in fulfilling the demand of clean liquid fuels. The evidence of consumption of carbon dioxide means that it need not to be removed from the syngas feed to the Fischer Tropsch reactor after the gasification process. Over the last five years, research at SIUC have shown that FTS in supercritical CO2reduces the selectivities for methane, enhances conversion, reduces the net CO2produces in the coal to liquid fuels process and increase the life of the catalyst. The research has already evaluated the impact of various operating and feed conditions on the FTS for the once through process. We believe that the integration of unreacted feed recycle would enhance conversion, increase the yield and throughput of liquid fuels for the same reactor size. The proposed research aims at evaluating the impact of recycle of the unreacted feed gas along with associated product gases on the performance of supercritical CO2FTS. The previously identified conditions will be utilized and various recycle ratios will be evaluated in this research once the recycle pump and associated fittings have been integrated to the supercritical CO2FTS. In this research two different catalysts (Fe-Zn-K, Fe-Co-Zn-K) were analyzed under SC-FTS in different recycle rate at 350oC and 1200 psi. The use of recycle was found to improve conversion from 80% to close to 100% with both catalysts. The experiment recycle rate at 4.32 and 4.91 was clearly surpassing theoretical recycle curve. The steady state reaction rate constant was increased to 0.65 and 0.8 min-1 for recycle rate of 4.32 and 4.91 respectively. Carbon dioxide selectivity was decreased for both catalyst as it was converting to carbon monoxide. Carbon dioxide consumption was increased from 0.014 to 0.034 mole fraction. This concluded that CO2is being used in the system and

Systematic framework for carbon dioxide capture and utilization processes to reduce the global carbon dioxide emissions

DEFF Research Database (Denmark)

Frauzem, Rebecca; Plaza, Cristina Calvera; Gani, Rafiqul

information-data on various carbon dioxide emission sources and available capture-utilization technologies; the model and solution libraries [2]; and the generic 3-stage approach for determining more sustainable solutions [3] through superstructure (processing networks) based optimization – adopted for global...... need to provide, amongst other options: useful data from in-house databases on carbon dioxide emission sources; mathematical models from a library of process-property models; numerical solvers from library of implemented solvers; and, work-flows and data-flows for different benefit scenarios...... to be investigated. It is useful to start by developing a prototype framework and then augmenting its application range by increasing the contents of its databases, libraries and work-flows and data-flows. The objective is to present such a prototype framework with its implemented database containing collected...

Carbon dioxide cleaning pilot project

International Nuclear Information System (INIS)

Knight, L.; Blackman, T.E.

1994-01-01

In 1989, radioactive-contaminated metal at the Rocky Flats Plant (RFP) was cleaned using a solvent paint stripper (Methylene chloride). One-third of the radioactive material was able to be recycled; two-thirds went to the scrap pile as low-level mixed waste. In addition, waste solvent solutions also required disposal. Not only was this an inefficient process, it was later prohibited by the Resource Conservation and Recovery Act (RCRA), 40 CFR 268. A better way of doing business was needed. In the search for a solution to this situation, it was decided to study the advantages of using a new technology - pelletized carbon dioxide cleaning. A proof of principle demonstration occurred in December 1990 to test whether such a system could clean radioactive-contaminated metal. The proof of principle demonstration was expanded in June 1992 with a pilot project. The purpose of the pilot project was three fold: (1) to clean metal so that it can satisfy free release criteria for residual radioactive contamination at the Rocky Flats Plant (RFP); (2) to compare two different carbon dioxide cleaning systems; and (3) to determine the cost-effectiveness of decontamination process in a production situation and compare the cost of shipping the metal off site for waste disposal. The pilot project was completed in August 1993. The results of the pilot project were: (1) 90% of those items which were decontaminated, successfully met the free release criteria , (2) the Alpheus Model 250 was selected to be used on plantsite and (3) the break even cost of decontaminating the metal vs shipping the contaminated material offsite for disposal was a cleaning rate of 90 pounds per hour, which was easily achieved

Carbon dioxide euthanasia in rats: Oxygen supplementation minimizes signs of agitation and asphyxia

NARCIS (Netherlands)

Coenen, A.M.L.; Drinkenburg, W.H.I.M.; Hoenderken, R.; Luijtelaar, E.L.J.M. van

1995-01-01

This paper records the effects of carbon dioxide when used for euthanasia, on behaviour, electrical brain activity and heart rate in rats. Four different methods were used. Animals were placed in a box (a) that was completely filled with carbon dioxide; (b) into which carbon dioxide was streamed at

27.12 MHz plasma generation in supercritical carbon dioxide

International Nuclear Information System (INIS)

Kawashima, Ayato; Toyota, Hiromichi; Nomura, Shinfuku; Takemori, Toshihiko; Mukasa, Shinobu; Maehara, Tsunehiro; Yamashita, Hiroshi

2007-01-01

An experiment was conducted for generating high-frequency plasma in supercritical carbon dioxide; it is expected to have the potential for applications in various types of practical processes. It was successfully generated at 6-20 MPa using electrodes mounted in a supercritical cell with a gap of 1 mm. Emission spectra were then measured to investigate the physical properties of supercritical carbon dioxide plasma. The results indicated that while the emission spectra for carbon dioxide and carbon monoxide could be mainly obtained at a low pressure, the emission spectra for atomic oxygen could be obtained in the supercritical state, which increased with the pressure. The temperature of the plasma in supercritical state was estimated to be approximately 6000-7000 K on the assumption of local thermodynamic equilibrium and the calculation results of thermal equilibrium composition in this state showed the increase of atomic oxygen by the decomposition of CO 2

Carbon dioxide may become a resource

International Nuclear Information System (INIS)

Haugneland, Petter; Areklett, Ivar

2002-01-01

The greenhouse gas CO 2 may become a product that the oil companies would pay for. In an extensive international resource project methods for CO 2 capture, transport and storage are being investigated. CO 2 capture means that carbon dioxide that is formed in the combustion of fossil fuels is separated out from the process, either from the fuel (decarbonization), or from the flue gas, and then stored. The article briefly describes the international joint project CO 2 Capture Project (CCP), in which eight oil companies are participating. If one can find a method for injecting CO 2 into oil reservoirs that leads to increased oil production, then part of the extra cost of removing the carbon dioxide from flue gas may be repaid

Robust optical carbon dioxide isotope analyzer, Phase I

Data.gov (United States)

National Aeronautics and Space Administration — Isotopic analysis of carbon dioxide is an important tool for characterization of the exchange and transformation of carbon between the biosphere and the atmosphere....

A supercritical carbon dioxide plasma process for preparing tungsten oxide nanowires

International Nuclear Information System (INIS)

Kawashima, Ayato; Nomura, Shinfuku; Toyota, Hiromichi; Takemori, Toshihiko; Mukasa, Shinobu; Maehara, Tsunehiro

2007-01-01

A supercritical carbon dioxide (CO 2 ) plasma process for fabricating one-dimensional tungsten oxide nanowires coated with amorphous carbon is presented. High-frequency plasma was generated in supercritical carbon dioxide at 20 MPa by using tungsten electrodes mounted in a supercritical cell, and subsequently an organic solvent was introduced with supercritical carbon dioxide into the plasma. Electron microscopy and Raman spectroscopy investigations of the deposited materials showed the production of tungsten oxide nanowires with or without an outer layer. The nanowires with an outer layer exhibited a coaxial structure with an outer concentric layer of amorphous carbon and an inner layer of tungsten oxide with a thickness and diameter of 20-30 and 10-20 nm, respectively

CQUESTRA, a risk and performance assessment code for geological sequestration of carbon dioxide

International Nuclear Information System (INIS)

LeNeveu, D.M.

2008-01-01

A computationally efficient semi-analytical code, CQUESTRA, has been developed for probabilistic risk assessment and rapid screening of potential sites for geological sequestration of carbon dioxide. The rate of dissolution and leakage from a trapped underground pool of carbon dioxide is determined. The trapped carbon dioxide could be mixed with hydrocarbons and other components to form a buoyant phase. The program considers potential mechanisms for escape from the geological formations such as the movement of the buoyant phase through failed seals in wellbores, the annulus around wellbores and through open fractures in the caprock. Plume animations of dissolved carbon dioxide in formation water around the wellbores are provided. Solubility, density and viscosity of the buoyant phase are determined by equations of state. Advection, dispersion, diffusion, buoyancy, aquifer flow rates and local formation fluid pressure are taken into account in the modeling of the carbon dioxide movement. Results from a hypothetical example simulation based on data from the Williston basin near Weyburn, Saskatchewan, indicate that this site is potentially a viable candidate for carbon dioxide sequestration. Sensitivity analysis of CQUESTRA indicates that criteria such as siting below aquifers with large flow rates and siting in reservoirs having fluid pressure below the pressure of the formations above can promote complete dissolution of the carbon dioxide during movement toward the surface, thereby preventing release to the biosphere. Formation of very small carbon dioxide bubbles within the fluid in the wellbores can also lead to complete dissolution

Carbon dioxide and the 'greenhouse effect': an unresolved problem

Energy Technology Data Exchange (ETDEWEB)

Smith, I

1978-01-01

This executive review evaluates current scientific literature concerned with the accumulation of carbon dioxide in the atmosphere. The extent and possible causes of natural variations in global climate are outlined as a background to potential variations due to human activity. Estimates are given on relative contributions of carbon dioxide to the atmosphere due to fossil fuel combustion, deforestation and other land modifications. The possibility of a rise in global temperature as a result of increasing the amount of carbon dioxide in the atmosphere is dicusssed including model predictions, natural factors which could compensate for or emphasize a warming effect, and the implications if extensive warming actually occurred. Carbon dioxide disposal is discussed, but there appears to be no practicable long-term means of accomplishing this. It is concluded that there is no evidence of a rise in global temperature due to carbon dioxide at present. Predictions, which involve a high degree of uncertainty, indicate that the global temperature could rise appreciably in the next century. An increase in precipitation rate is also expected. If these changes result in a redistribution of climatic zones, there may be problems in adapting agricultural belts in some regions. Complete melting of all the ice sheets would take several millenia. A partial melting of continental ice sheets would not necessarily occur in view of the increase in precipitation rates, but if it did, there would be a rise in sea level of a few metres. Melting of the Arctic sea ice would affect climate, but not sea level.

Carbon Dioxide Sensor Technology.

Science.gov (United States)

1983-04-01

second gas permeable membrane separates a compartment containing the non-aqueous " solvent dimethylsulfoxide , ( DMSO ), from the aqueous solution...compartment. In DMSO carbon dioxide can be irreversibly reduced electrochemically to * non-interfering products...current due to its reduction in the DMSO solution is proportional to the partial pressure of CO2 in the gas phase. Overall, the linear response and

Production and emission of methane and carbon dioxide by ruminants

International Nuclear Information System (INIS)

Chouinard, Y.

2003-01-01

Animal digestion is responsible for the production of both carbon dioxide and methane, while breathing produces only carbon dioxide. The author described the digestion mechanism of ruminants, explaining that they produce higher levels of methane and carbon dioxide than other animals. Fermentation stoichiometry of ruminants was also discussed along with the influence that diet has on methane production. It was noted that methane production can be decreased by increasing animal productivity, or by using ionophore antibiotics and long chain fatty acids. Test results from each of these methods have revealed side effects and none appears to be applicable for the time being. 10 refs., 1 tab., 1 fig

Nanostructured membrane material designed for carbon dioxide separation

KAUST Repository

Yave, Wilfredo; Car, Anja; Peinemann, Klaus-Viktor

2010-01-01

In this work carbon dioxide selective membrane materials from a commercially available poly(amide-b-ethylene oxide) (Pebax (R), Arkema) blended with polyethylene glycol ethers are presented. The preferred PEG-ether was PEG-dimethylether (PEG-DME). PEG-DME is well known as a physical solvent for acid gas absorption. It is used under the trade name Genosorb (R) in the Selexol (R) process (UOP) for acid gas removal from natural gas and synthesis gas. The combination of the liquid absorbent with the multiblock copolymer resulted in mechanically stable films with superior CO(2) separation properties. The addition of 50 wt.% PEG-DME to the copolymer resulted in a 8-fold increase of the carbon dioxide permeability; the CO(2)/H(2)-selectivity increased simultaneously from 9.1 to 14.9. It is shown that diffusivity as well as solubility of carbon dioxide is strongly increased by the blending of the copolymer with PEG-ethers. (c) 2009 Elsevier B.V. All rights reserved.

Nanostructured membrane material designed for carbon dioxide separation

KAUST Repository

Yave, Wilfredo

2010-03-15

In this work carbon dioxide selective membrane materials from a commercially available poly(amide-b-ethylene oxide) (Pebax (R), Arkema) blended with polyethylene glycol ethers are presented. The preferred PEG-ether was PEG-dimethylether (PEG-DME). PEG-DME is well known as a physical solvent for acid gas absorption. It is used under the trade name Genosorb (R) in the Selexol (R) process (UOP) for acid gas removal from natural gas and synthesis gas. The combination of the liquid absorbent with the multiblock copolymer resulted in mechanically stable films with superior CO(2) separation properties. The addition of 50 wt.% PEG-DME to the copolymer resulted in a 8-fold increase of the carbon dioxide permeability; the CO(2)/H(2)-selectivity increased simultaneously from 9.1 to 14.9. It is shown that diffusivity as well as solubility of carbon dioxide is strongly increased by the blending of the copolymer with PEG-ethers. (c) 2009 Elsevier B.V. All rights reserved.

Reactor design considerations in mineral sequestration of carbon dioxide

International Nuclear Information System (INIS)

Ityokumbul, M.T.; Chander, S.; O'Connor, William K.; Dahlin, David C.; Gerdemann, Stephen J.

2001-01-01

One of the promising approaches to lowering the anthropogenic carbon dioxide levels in the atmosphere is mineral sequestration. In this approach, the carbon dioxide reacts with alkaline earth containing silicate minerals forming magnesium and/or calcium carbonates. Mineral carbonation is a multiphase reaction process involving gas, liquid and solid phases. The effective design and scale-up of the slurry reactor for mineral carbonation will require careful delineation of the rate determining step and how it changes with the scale of the reactor. The shrinking core model was used to describe the mineral carbonation reaction. Analysis of laboratory data indicates that the transformations of olivine and serpentine are controlled by chemical reaction and diffusion through an ash layer respectively. Rate parameters for olivine and serpentine carbonation are estimated from the laboratory data

Solid amine which is marked as a carbon dioxide absorbing and desorbing agent. Tansan gas no kyudacchakuzai to shite chumoku sareru kotai amin

Energy Technology Data Exchange (ETDEWEB)

Otsubo, Koji

1990-01-01

These days, phenomenon of the global warming due to the increase of carbon dioxide has become a great problem. Also in a space craft, in order to maintain human lives a system to get rid of carbon dioxide which is increased in the living sphere is required. As an agent to get rid of carbon dioxide in space, gas or liquid are hard to use, and moreover the agent must be highly reliable, energy conservative, of light weight and compact. Taking above conditions into consideration, trade-off was carried out on present technologies which might be of use. As a result, it was concluded that use of solid amine which has high selective absorbing capacity of carbon dioxide is most probable. In a system using solid amine; in order to make the area which touches air maximum, solid amine is made into small balls of 50 - 500 micro m diameters, and two pairs of canisters which make it possible to maintain solid amine and make adsorption and desorption easy are applied. And in the system alternative adsorption and desorption of carbon dioxide continues. Carbon dioxide recovered is to be used for a plant growing system in a space craft. Long term characteristic tests of the system are being carried out. 4 figs.

Carbon dioxide retention in divers

Energy Technology Data Exchange (ETDEWEB)

Florio, J.T.; Mackenzie, D.A.R.; McKenzie, R.S. [ARE Physiological Laboratory, Gosport (United Kingdom)

1998-04-01

This report summarises the work carried out at the ARE Physiological Laboratory (ARE(PL)) between July 1978 and December 1983. The work was intended to examine the proposition that some divers have a low ventilatory response to carbon dioxide; that this results in a low ventilatory response to exercise with consequent hypercapnia; and that these characteristics put the diver at a greater-than-normal risk by increasing the individual`s susceptibility to oxygen toxicity and to other hazards associated with diving (e.g. nitrogen narcosis, decompression sickness and hypothermia). The specific aims of the project can be summarised as follows: (a) to demonstrate the existence of divers who exhibit the tendency to `retain carbon dioxide` when working in hyperbaric conditions; (b) to define the circumstances under which such individuals are at risk; (c) to assess the magnitude of the risk; and (d) to recommend ways to eliminate or to reduce the risk. (author)

Anaesthesia for laparoscopic nephrectomy: Does end-tidal carbon dioxide measurement correlate with arterial carbon dioxide measurement?

Science.gov (United States)

Jayan, Nithin; Jacob, Jaya Susan; Mathew, Mohan

2018-04-01

Not many studies have explored the correlation between arterial carbon dioxide tension (PaCO 2 ) and end-tidal carbon dioxide tension (ETCO 2 ) in surgeries requiring pneumoperitoneum of more than 1 hour duration with the patient in non-supine position. The aim of our study was to evaluate the correlation of ETCO 2 with PaCO 2 in patients undergoing laparoscopic nephrectomy under general anaesthesia. A descriptive study was performed in thirty patients undergoing laparoscopic nephrectomy from September 2014 to August 2015. The haemodynamic parameters, minute ventilation, PaCO 2 and ETCO 2 measured at three predetermined points during the procedure were analysed. Correlation was checked using Pearson's Correlation Coefficient Test. P <0.05 was considered statistically significant. Statistical analysis of the values showed a positive correlation between ETCO 2 and PaCO 2 ( P < 0.05). Following carbon dioxide insufflation, both ETCO 2 and PaCO 2 increased by 5.4 and 6.63 mmHg, respectively, at the end of the 1 st hour. The PaCO 2 -ETCO 2 gradient was found to increase during the 1 st hour following insufflation (4.07 ± 2.05 mmHg); it returned to the pre-insufflation values in another hour (2.93 ± 1.43 mmHg). Continuous ETCO 2 monitoring is a reliable indicator of the trend in arterial CO 2 fluctuations in the American Society of Anesthesiologists Grades 1 and 2 patients undergoing laparoscopic nephrectomy under general anaesthesia.

Optimization of the Carbon Dioxide Removal Assembly (CDRA-4EU) in Support of the International Space System and Advanced Exploration Systems

Science.gov (United States)

Knox, James C.; Stanley, Christine M.

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 Carbon Dioxide (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 utilizes a virtual Carbon Dioxide Removal Assembly, revision 4 (CDRA-4) test bed to test a large number of potential operational configurations with independent variations in flow rate, cycle time, heater ramp rate, and set point. Initial ground testing will provide prerequisite source data and provide baseline data in support of the virtual CDRA. Once the configurations with the highest performance and lowest power requirements are determined by the virtual CDRA, the results will be confirmed by testing these configurations with the CDRA-4EU ground test hardware. This paper describes the initial ground testing of select configurations. The development of the virtual CDRA under the AES-LSS Project will be discussed in a companion paper.

Environmental effects of increased atmospheric carbon dioxide

International Nuclear Information System (INIS)

Soon, W.; Baliunas, S.L.; Robinson, A.B.; Robinson, Z.W.

1999-01-01

A review of the literature concerning the environmental consequences of increased levels of atmospheric carbon dioxide leads to the conclusion that increases during the 20th century have produced no deleterious effects upon global climate or temperature. Increased carbon dioxide has, however, markedly increased plant growth rates as inferred from numerous laboratory and field experiments. There is no clear evidence, nor unique attribution, of the global effects of anthropogenic CO 2 on climate. Meaningful integrated assessments of the environmental impacts of anthropogenic CO 2 are not yet possible because model estimates of global and regional climate changes on interannual, decadal and centennial timescales remain highly uncertain.(author)

Research on urban road congestion pricing strategy considering carbon dioxide emissions

NARCIS (Netherlands)

Wang, Y.; Peng, Z.; Wang, K.; Song, X.; Yao, B.; Feng, T.

2015-01-01

Congestion pricing strategy has been recognized as an effective countermeasure in the practical field of urban traffic congestion mitigation. In this paper, a bi-level programming model considering carbon dioxide emission is proposed to mitigate traffic congestion and reduce carbon dioxide

Utilisation of flue gases from biofuels in greenhouses as carbon dioxide source

International Nuclear Information System (INIS)

Kuopanportti, H.; Rissanen, R.; Vuollet, A.; Kanniainen, T.; Tikka, A.; Ramm-Chmidt, L.; Seppaelae, R.; Piira, T.

2006-01-01

The objectives of the project is to develop technologies by which the flue gases from burning bio fuels and peat can be purified for used in green houses as a low cost source of carbon dioxide. Traditionally carbon dioxide has been produced by burning propane or natural gas or by injecting bottled carbon dioxide gas directly into the green house. The new methods should be more affordable than the present ones. (orig.)

Effect of lithium tetrafluoroborate on the solubility of carbon dioxide in the ionic liquid 1-butyl-3-methylimidazolium tetrafluoroborate

NARCIS (Netherlands)

Durano Arno, S.; Lucas, S.; Shariati - Sarabi, A.; Peters, C.J.

2012-01-01

In this work, the phase behavior of the ternary system of carbon dioxide +1-butyl-3-methylimidazolium tetrafluoroborate + lithium tetrafluoroborate has been investigated. Mixtures of known concentrations of the salt, ionic liquid and carbon dioxide were prepared and their bubble point pressures were

Development Requirements for the Exploration PLSS (xPLSS) Carbon Dioxide and Humidity Control Unit (CDHCU)

Science.gov (United States)

Chullen, Cinda

2017-01-01

Functional Requirements for the Carbon Dioxide and Humidity Control Unit (CDHCU): The CDHCU is a component of the Exploration Portable Life Support System (xPLSS) to provide carbon dioxide (CO2) and humidity control within the spacesuit for a crewmember to perform extravehicular activities (EVA) in vacuum (micro-g), lunar, and Mars environments for up to 8 hours continuous, and during EVA preparation in airlocks or support vehicles for an additional 2 hours (TBR) continuous.

Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends Data

Data.gov (United States)

U.S. Environmental Protection Agency — The Light-Duty Automotive Technology, Carbon Dioxide Emissions, and Fuel Economy Trends report is the authoritative reference for carbon dioxide (CO2) emissions,...

Removal of carbon dioxide in reprocessing spent nuclear fuel off gas by adsorption

International Nuclear Information System (INIS)

Fukumatsu, Teruki; Munakata, Kenzo; Tanaka, Kenji; Yamatsuki, Satoshi; Nishikawa, Masabumi

1998-01-01

The off gas produced by reprocessing spent nuclear fuel includes various radioactivities and these nuclei should be removed. In particular, 14 C mainly released as the form of carbon dioxide is one of the most required gaseous radioactivities to be removed because it has long a half-life. One of the methods to remove gaseous nuclei is the use of adsorption technique. The off gas contains water vapor which influences adsorption process of carbon dioxide. In this report, behavior of adsorption of carbon dioxide on various adsorbent and influence on adsorption behavior of carbon dioxide by containing water vapor are discussed. (author)

The carbon-nitrogen balance of the nodule and its regulation under elevated carbon dioxide concentration.

Science.gov (United States)

Libault, Marc

2014-01-01

Legumes have developed a unique way to interact with bacteria: in addition to preventing infection from pathogenic bacteria like any other plant, legumes also developed a mutualistic symbiotic relationship with one gender of soil bacteria: rhizobium. This interaction leads to the development of a new root organ, the nodule, where the differentiated bacteria fix for the plant the atmospheric dinitrogen (atmN2). In exchange, the symbiont will benefit from a permanent source of carbon compounds, products of the photosynthesis. The substantial amounts of fixed carbon dioxide dedicated to the symbiont imposed to the plant a tight regulation of the nodulation process to balance carbon and nitrogen incomes and outcomes. Climate change including the increase of the concentration of the atmospheric carbon dioxide is going to modify the rates of plant photosynthesis, the balance between nitrogen and carbon, and, as a consequence, the regulatory mechanisms of the nodulation process. This review focuses on the regulatory mechanisms controlling carbon/nitrogen balances in the context of legume nodulation and discusses how the change in atmospheric carbon dioxide concentration could affect nodulation efficiency.

Measurement of carbon dioxide fluxes in a free-air carbon dioxide enrichment experiment using the closed flux chamber technique

DEFF Research Database (Denmark)

Selsted, Merete Bang; Ambus, Per; Michelsen, Anders

2011-01-01

Carbon dioxide (CO2) fluxes, composing net ecosystem exchange (NEE), ecosystem respiration (ER), and soil respiration (SR) were measured in a temperate heathland exposed to elevated CO2 by the FACE (free-air carbon enrichment) technique, raising the atmospheric CO2 concentration from c. 380 μmol...

Geologic map showing springs rich in carbon dioxide or or chloride in California

Science.gov (United States)

Barnes, Ivan; Irwin, William P.; Gibson, H.A.

1975-01-01

Carbon dioxide- and chloride-rich springs occur in all geologic provinces in California, but are most abundant in the Coast Ranges and the Great Valley. The carbon-dioxide-rich springs issue mainly from Franciscan terrane; they also are rich in boron and are of the metamorphic type (White, 1957). Based on isotopic data, either the carbon dioxide or the water, or both, may be of metamorphic origin. Because of high magnesium values, the water of many of the carbon-dioxide-rich springs is thought to have passed through serpentinite. The chloride-rich waters are most common in rocks of the Great Valley sequence. Nearly all are more dilute than present-day sea water. The similarity in isotopic compositions of the metamorphic carbon-dioxide-rich water and the chloride-rich water may indicate a similar extent of water-rock interaction.

The Australian coal industry: now, and the future under carbon dioxide emission restrictions

International Nuclear Information System (INIS)

Cain, D.A.

1990-01-01

Coal produces more carbon dioxide per unit of combustion energy than other fossil fuels. Therefore, reducing coal consumption is commonly advocated as one way to control greenhouse gas emissions and hence predicted global warming. Australia is highly dependent on coal, both as a primary energy source and as a major export commodity. Action to reduce carbon dioxide emissions by substantially decreasing coal consumption would have a very serious impact on the Australian coal industry and the Australian economy. Australia's dependence on coal and the potential conflict between the objective of further processing Australia's mineral exports and calls to limit carbon dioxide emissions is described. The effect on coal consumption of one scenario for reducing Australia's carbon dioxide emissions from electricity generation and possible effects of global carbon dioxide emission reductions on world coal trade are discussed. 24 refs., 2 tabs., 4 figs

Automatic Carbon Dioxide-Methane Gas Sensor Based on the Solubility of Gases in Water

Directory of Open Access Journals (Sweden)

Raúl O. Cadena-Pereda

2012-08-01

Full Text Available Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed. The contribution of this work is the development of a novel, simple and low cost automatic carbon dioxide-methane gas sensor based on the solubility of gases in water as the precursor of a sensor for biogas quality monitoring. The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0–100%. The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.

Automatic carbon dioxide-methane gas sensor based on the solubility of gases in water.

Science.gov (United States)

Cadena-Pereda, Raúl O; Rivera-Muñoz, Eric M; Herrera-Ruiz, Gilberto; Gomez-Melendez, Domingo J; Anaya-Rivera, Ely K

2012-01-01

Biogas methane content is a relevant variable in anaerobic digestion processing where knowledge of process kinetics or an early indicator of digester failure is needed. The contribution of this work is the development of a novel, simple and low cost automatic carbon dioxide-methane gas sensor based on the solubility of gases in water as the precursor of a sensor for biogas quality monitoring. The device described in this work was used for determining the composition of binary mixtures, such as carbon dioxide-methane, in the range of 0-100%. The design and implementation of a digital signal processor and control system into a low-cost Field Programmable Gate Array (FPGA) platform has permitted the successful application of data acquisition, data distribution and digital data processing, making the construction of a standalone carbon dioxide-methane gas sensor possible.

Reactivity of dolomite in water-saturated supercritical carbon dioxide: Significance for carbon capture and storage and for enhanced oil and gas recovery

International Nuclear Information System (INIS)

Wang Xiuyu; Alvarado, Vladimir; Swoboda-Colberg, Norbert; Kaszuba, John P.

2013-01-01

Highlights: ► Dolomite reactivity with wet and dry supercritical CO 2 were evaluated. ► Dolomite does not react with dry CO 2 . ► H 2 O-saturated supercritical CO 2 dissolves dolomite and precipitates carbonate mineral. ► Temperature/reaction time control morphology and extent of carbonate mineralization. ► Reaction with wet CO 2 may impact trapping, caprock integrity, and CCS/EOR injectivity. - Abstract: Carbon dioxide injection in porous reservoirs is the basis for carbon capture and storage, enhanced oil and gas recovery. Injected carbon dioxide is stored at multiple scales in porous media, from the pore-level as a residual phase to large scales as macroscopic accumulations by the injection site, under the caprock and at reservoir internal capillary pressure barriers. These carbon dioxide saturation zones create regions across which the full spectrum of mutual CO 2 –H 2 O solubility may occur. Most studies assume that geochemical reaction is restricted to rocks and carbon dioxide-saturated formation waters, but this paradigm ignores injection of anhydrous carbon dioxide against brine and water-alternating-gas flooding for enhanced oil recovery. A series of laboratory experiments was performed to evaluate the reactivity of the common reservoir mineral dolomite with water-saturated supercritical carbon dioxide. Experiments were conducted at reservoir conditions (55 and 110 °C, 25 MPa) and elevated temperature (220 °C, 25 MPa) for approximately 96 and 164 h (4 and 7 days). Dolomite dissolves and new carbonate mineral precipitates by reaction with water-saturated supercritical carbon dioxide. Dolomite does not react with anhydrous supercritical carbon dioxide. Temperature and reaction time control the composition, morphology, and extent of formation of new carbonate minerals. Mineral dissolution and re-precipitation due to reaction with water-saturated carbon dioxide may affect the contact line between phases, the carbon dioxide contact angle, and the

Supercritical Carbon Dioxide–Based Sterilization of Decellularized Heart Valves

Directory of Open Access Journals (Sweden)

Ryan S. Hennessy, MD

2017-02-01

Full Text Available Summary: Sterilization of grafts is essential. Supercritical carbon dioxide, electrolyzed water, gamma radiation, ethanol-peracetic acid, and hydrogen peroxide techniques were compared for impact on sterility and mechanical integrity of porcine decellularized aortic valves. Ethanol-peracetic acid– and supercritical carbon dioxide–treated valves were found to be sterile using histology, microbe culture, and electron microscopy assays. The cusp tensile properties of supercritical carbon dioxide–treated valves were higher compared with valves treated with other techniques. Superior sterility and integrity was found in the decellularized valves treated with supercritical carbon dioxide sterilization. This sterilization technique may hold promise for other decellularized soft tissues. Key Words: decellularized, decontamination, heart valve, tensile properties, tissue engineering

High-Pressure Phase Behavior of Polycaprolactone, Carbon Dioxide, and Dichloromethane Ternary Mixture Systems

Energy Technology Data Exchange (ETDEWEB)

Gwon, JungMin; Kim, Hwayong [Seoul National University, Seoul (Korea, Republic of); Shin, Hun Yong [Seoul National University of Science and Technology, Seoul (Korea, Republic of); Kim, Soo Hyun [Korea Institute of Science and Technology, Seoul (Korea, Republic of)

2015-04-15

The high-pressure phase behavior of a polycaprolactone (Mw=56,145 g/mol, polydispersity 1.2), dichloromethane, and carbon dioxide ternary system was measured using a variable-volume view cell. The experimental temperatures and pressures ranged from 313.15 K to 353.15 K and up to 300 bar as functions of the CO{sub 2}/dichloromethane mass ratio and temperature, at poly(D-lactic acid) weight fractions of 1.0, 2.0, and 3.0%. The correlation results were obtained from the hybrid equation of state (Peng-Robinson equation of state + SAFT equation of state) for the CO{sub 2}-polymer system using the van der Waals one-fluid mixing rule. The three binary interaction parameters were optimized by the simplex method algorithm.

Carbon dioxide: making the right connection

African Journals Online (AJOL)

This highlights safety issues concerning pipeline provision of carbon dioxide, and that it is of utmost ... capnograph sample line, gas analysis unit, water trap and soda .... The heat generated by the chemical reaction between soda lime.

Fixation of carbon dioxide by coral reef. Sangosho ni yoru CO2 no kotei

Energy Technology Data Exchange (ETDEWEB)

Yamamuro, M [Geological Survey of Japan, Tsukuba, Ibaraki (Japan)

1993-08-01

The methods for fixation of carbon dioxide in the atmosphere in order to control the greenhouse effect, are groped. Carbon is fixed through two ways such as the production of organic compounds by photosynthesis and formation of calcium carbonate by calcification. Among them, the photosynthesis fixes carbon dioxide in the air, and calcification, on thinking of only chemical equilibrium in the sea water, is a process to exhaust carbon dioxide from ocean to the atmosphere. It is, therefore, uneven in opinions of researchers if the coral reef is an absorbing source or an exhausting one of carbon dioxide. A conventional discussion on this theme, did not carry out based on the actual search or measurement, but preceded on modelling. In order, therefore, to introduce a scientific decision on a play of the coral reef for the global carbon circulation, it seems to take more time. In this paper, an opinion that the coral reef is an absorbing source of carbon dioxide in the air according to some measuring results of carbon dioxide fixation velocity and organic compounds volume in sediments in the coral reefs, are described. 11 refs., 4 figs.

Apparatus for extracting and sequestering carbon dioxide

Science.gov (United States)

Rau, Gregory H [Castro Valley, CA; Caldeira, Kenneth G [Livermore, CA

2010-02-02

An apparatus and method associated therewith to extract and sequester carbon dioxide (CO.sub.2) from a stream or volume of gas wherein said apparatus hydrates CO.sub.2 and reacts the resulting carbonic acid with carbonate. Suitable carbonates include, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO.sub.2 from a gaseous environment.

Method for Extracting and Sequestering Carbon Dioxide

Energy Technology Data Exchange (ETDEWEB)

Rau, Gregory H.; Caldeira, Kenneth G.

2005-05-10

A method and apparatus to extract and sequester carbon dioxide (CO2) from a stream or volume of gas wherein said method and apparatus hydrates CO2, and reacts the resulting carbonic acid with carbonate. Suitable carbonates include, but are not limited to, carbonates of alkali metals and alkaline earth metals, preferably carbonates of calcium and magnesium. Waste products are metal cations and bicarbonate in solution or dehydrated metal salts, which when disposed of in a large body of water provide an effective way of sequestering CO2 from a gaseous environment.

Carbon dioxide efflux from leaves in light and darkness

Energy Technology Data Exchange (ETDEWEB)

Holmgren, P; Jarvis, P G

1967-01-01

The efflux of carbon dioxide in light and darkness was measured at low ambient CO/sub 2/ concentrations in leaves of Rumex acetosa. Light carbon dioxide production (photorespiration) was found to depend on irradiance and to differ from dark production as to the response to temperature and ambient concentrations of O/sub 2/ and CO/sub 2/. These observations support previously made suggestions that photorespiration follows a different metabolic pathway to dark respiration.

Arbuscular mycorrhizal fungi increase organic carbon decomposition under elevated carbon dioxide

Science.gov (United States)

A major goal of climate change research is to understand whether and how terrestrial ecosystems can sequester more carbon to mitigate rising atmospheric carbon dioxide (CO2) levels. The stimulation of arbuscular mycorrhizal fungi (AMF) by elevated atmospheric CO2 has been assumed to be a major mecha...

Kinetics of absorption of carbon dioxide in aqueous amine and carbonate solutions with carbonic anhydrase

NARCIS (Netherlands)

Penders-van Elk, Nathalie J. M. C.; Hamborg, Espen S.; Huttenhuis, Patrick J. G.; Fradette, Sylvie; Carley, Jonathan A.; Versteeg, Geert F.

In the present work the absorption of carbon dioxide in aqueous N-methyldiethanolamine (MDEA) and aqueous sodium carbonate with and without carbonic anhydrase (CA) was studied in a stirred cell contactor in the temperature range 298-333 K. The CA was present as free enzyme and is compared to the

Phase behaviour and thermodynamic modelling for the system (grape seed oil + carbon dioxide + ethanol) at high pressures

International Nuclear Information System (INIS)

Dalmolin, Irede; Rigo, Aline A.; Corazza, Marcos L.; Ndiaye, Papa M.; Meireles, M. Angela A.; Batista, Eduardo A.C.; Oliveira, J. Vladimir

2014-01-01

This short communication reports phase equilibrium data (cloud points), employing the synthetic static method, for the system {grape seed oil (GSO) + carbon dioxide (CO 2 ) + ethanol} up to T = 343.15 K and 22.53 MPa. Experimental results were modelled using the Peng-Robinson equation of state with the classical van der Waals quadratic mixing rule (PR-vdW2). It is shown that the thermodynamic model is able to represent satisfactorily the phase behaviour of the system investigated

Sequestering carbon dioxide in industrial polymers: Building materials for the 21st century

Energy Technology Data Exchange (ETDEWEB)

Molton, P.M.; Nelson, D.A.

1993-06-01

This study was undertaken to determine the possibility of developing beneficial uses for carbon dioxide as a key component for a large-volume building product. Such a use may provide an alternative to storing the gas in oceanic sinks or clathrates as a way to slow the rate of global warming. The authors investigated the concept that carbon dioxide might be used with other chemicals to make carbon-dioxide-based polymers which would be lightweight, strong, and economical alternatives to some types of wood and silica-based building materials. As a construction-grade material, carbon dioxide would be fixed in a solid, useful form where it would not contribute to global warming. With the probable imposition of a fuel carbon tax in industrialized countries, this alternative would allow beneficial use of the carbon dioxide and could remove it from the tax basis if legislation were structured appropriately. Hence, there would be an economic driver towards the use of carbon-dioxide-based polymers which would enhance their future applications. Information was obtained through literature searches and personal contacts on carbon dioxide polymers which showed that the concept (1) is technically feasible, (2) is economically defensible, and (3) has an existing industrial infrastructure which could logically develop it. The technology exists for production of building materials which are strong enough for use by industry and which contain up to 90% by weight of carbon dioxide, both chemically and physically bound. A significant side-benefit of using this material would be that it is self-extinguishing in case of fire. This report is the first stage in the investigation. Further work being proposed will provide details on costs, specific applications and volumes, and potential impacts of this technology.

High-resolution carbon dioxide concentration record 650,000-800,000 years before present

DEFF Research Database (Denmark)

Lüthi, Dieter; Le Floch, Martine; Bereiter, Bernhard

2008-01-01

Changes in past atmospheric carbon dioxide concentrations can be determined by measuring the composition of air trapped in ice cores from Antarctica. So far, the Antarctic Vostok and EPICA Dome C ice cores have provided a composite record of atmospheric carbon dioxide levels over the past 650......,000 years. Here we present results of the lowest 200 m of the Dome C ice core, extending the record of atmospheric carbon dioxide concentration by two complete glacial cycles to 800,000 yr before present. From previously published data and the present work, we find that atmospheric carbon dioxide...... is strongly correlated with Antarctic temperature throughout eight glacial cycles but with significantly lower concentrations between 650,000 and 750,000 yr before present. Carbon dioxide levels are below 180 parts per million by volume (p.p.m.v.) for a period of 3,000 yr during Marine Isotope Stage 16...

An in situ infrared study of dimethyl carbonate synthesis from carbon dioxide and methanol over zirconia

International Nuclear Information System (INIS)

Jung, Kyeong Taek; Bell, Alexis T.

2001-01-01

The mechanism of dimethyl carbonate (DMC) synthesis from methanol and carbon dioxide over monoclinic zirconia has been investigated using in situ infrared spectroscopy. The dissociative adsorption of methanol occurs more slowly than the adsorption of carbon dioxide, but the species formed from methanol are bound more strongly. Upon adsorption, the oxygen atom of methanol binds to coordinately unsaturated Zr4+ cations present at the catalyst surface. Rapid dissociation of the adsorbed methanol leads to the formation of a methoxide group (Zr-OCH3) and the release of a proton, which reacts with a surface hydroxyl group to produce water. Carbon dioxide inserts in the Zr-O bond of the methoxide to form a mondentate methyl carbonate group (Zr-OC(O)OCH3). This process is facilitated by the interactions of C and O atoms in CO2 with Lewis acid-base pairs of sites (Zr4+O2-) on the surface of the catalyst. Methyl carbonate species can also be produced via the reaction of methanol with carbon dioxide adsorbed in the form of bicarbonate species with methanol, a process that results in the transfer of a methyl group to the carbonate and restores a hydroxyl group to the zirconia surface. The decomposition of DMC on monoclinic zirconia has also been investigated and has been observed to occur via the reverse of the processes described for the synthesis of DMC

Carbon dioxide emissions due to Swedish imports and consumption: estimates using different methods

International Nuclear Information System (INIS)

Carlsson-Kanyama, Annika; Assefa, Getachew; Wadeskog, Anders

2007-04-01

Global trade of products and services challenges the traditional way in which emissions of carbon dioxide are declared and accounted for. Instead of only considering territorial emissions there are now strong reasons to determine how the carbon dioxide emitted in the production of imports are partitioned around the world and how the total emissions change for a country's final consumption compared to final production. In this report results from four different methods of calculating the total carbon dioxide emissions from Sweden's overall consumption are presented. Total carbon dioxide emissions for Sweden's final consumption vary from 57 to 109 M tons during one year depending on the methodology. The four methods used for estimating these emissions give results of 57, 61, 68 and 109 Mton of carbon dioxide. Two methods are based on information concerning Sweden's imports and our national production of goods and services excluding production that is exported while two methods are based on final consumer expenditures. Three of the methods use mainly emission data from Sweden while one method depends entirely upon emission data from Sweden's trading partners. The last method also gives the highest emissions level, 109 Mton of carbon dioxide. The calculations performed here can be compared to the emissions reported by Sweden, 54 Mton of carbon dioxide per year. Our estimates give per capita emission levels of between 6,3 and 12 tons of carbon dioxide per year. The estimate of 12 tons per capita is a result of using emissions data from Sweden's trading partners. The total emissions as a result of Sweden's imports are 26 or 74 M tons of carbon dioxide depending on how they are calculated. The lower figure is based upon the imports of today but with emissions as if everything was produced as in Sweden. The higher level is based upon using existing but partly inadequate international emission statistics. These levels can be compared to the about 35 M tons of carbon dioxide

The use of the carbon dioxide laser in head and neck lymphangioma.

Science.gov (United States)

White, B; Adkins, W Y

1986-01-01

The carbon dioxide laser has been used to treat various lesions of the head and neck, ranging from carcinomas to hemangiomas, and even including tatoos. A search of the literature does not reveal any reports of the carbon dioxide laser being used to treat lymphangioma. This report discusses the efficacy of treating lymphangioma of the air and food passages with the carbon dioxide laser, and presents three patients who have been treated in this fashion-two for palliation and one for cure.

Nongovernmental valorization of carbon dioxide

International Nuclear Information System (INIS)

Petersen, Gene; Viviani, Donn; Magrini-Bair, Kim; Kelley, Stephen; Moens, Luc; Shepherd, Phil; DuBois, Dan

2005-01-01

Carbon dioxide (CO 2 ) is considered the largest contributor to the greenhouse gas effect. Most attempts to manage the flow of CO 2 or carbon into our environment involve reducing net emissions or sequestering the gas into long-lived sinks. Using CO 2 as a chemical feedstock has a long history, but using it on scales that might impact the net emissions of CO 2 into the atmosphere has not generally been considered seriously. There is also a growing interest in employing our natural biomes of carbon such as trees, vegetation, and soils as storage media. Some amelioration of the net carbon emissions into the atmosphere could be achieved by concomitant large withdrawals of carbon. This report surveys the potential and limitations in employing carbon as a resource for organic chemicals, fuels, inorganic materials, and in using the biome to manage carbon. The outlook for each of these opportunities is also described

Evaluation of a transportable capnometer for monitoring end-tidal carbon dioxide

DEFF Research Database (Denmark)

Hildebrandt, T; Tobiasen, Malene Espelund; Olsen, K S

2010-01-01

We compared a small and transportable Capnometer (EMMA™) with a reference capnometer, the Siesta i TS Anaesthesia. During air-breathing through a facemask, both the EMMA (nine modules) and reference capnometer sampled expired gas simultaneously. A wide range of end-tidal carbon dioxide values were...... obtained during inhalation of carbon dioxide and voluntary hyperventilation. The median IQR [range] difference between all sets of carbon dioxide values (EMMA - reference) was -0.3 (-0.6 to 0.0 [-1.7 to 1.6] kPa; n = 297) using new batteries, which was statistically significant (p = 0.04) and located...... to two of the nine EMMAs tested. Using batteries with reduced voltage did not influence the measurements. The 95% CI of the medians of the differences were -0.4 to -0.2. We conclude that the EMMA can slightly under-read the end-tidal carbon dioxide but is generally comparable with a free-standing monitor...

Reaction of phosphorus ylides with carbonyl compounds in supercritical carbon dioxide

International Nuclear Information System (INIS)

Jeong, Kyung Il; Kim, Hak Do; Shim, Jae Jin; Ra, Choon Sup

2004-01-01

The condensation reaction of (benzylene)triphenylphosphoranes with carbonyl compounds in supercritical carbon dioxide was examined. Reactions of (benzylene)phosphoranes (ca. 1 mmol) with several benzaldehydes in a supercritical carbon dioxide (80 .deg. C, 2,000 psi) containing THF entrainer (5%) in a 24 mL reactor proceed smoothly to yield olefination products in fairly good to excellent yields but slower, compared to reactions in a conventional THF solvent. Generally, phosphoranes that are not substituted with a nitro group show more (Z)-selective reactions with aromatic aldehydes under scCO 2 condition than in THF. The reaction of (benzylene)triphenylphosphosphoranes with 4-t-butylcyclohexanone gave the corresponding olefin compounds with a low conversion under both the supercritical carbon dioxide and the organic THF solvent. Our preliminary study showed the Wittig reaction carries out smoothly in supercritical carbon dioxide medium and also a possible tunability of this reaction pathway by adding a entrainer. The results would be useful for devising a novel process for the environmentally friendly Wittig reaction

Carbon dioxide capture from exhaust gases by selective adsorption on porous solids

Energy Technology Data Exchange (ETDEWEB)

Schindler, M.; Ernst, S. [Technische Univ. Kaiserslautern (Germany). Dept. of Chemistry

2007-07-01

The metal-organic frameworks Cu{sub 3}(BTC){sub 2}, MIL-53 and MIL-96 were synthesized and characterized by powder X-ray diffraction, scanning electron microscopy and nitrogenphysisorption. The adsorption isotherms for carbon dioxide at temperatures of 20, 40 and 60 C and pressures up to 1000 mbar on this new type of microporous solids were measured by a static volumetric method. For comparison, experiments with zeolite NaX (13X) were also included. High adsorption capacities for carbon dioxide were found for the adsorbents investigated in this study. The breakthrough curves for the adsorption of a mixture of nitrogen and carbon dioxide on Cu{sub 3}(BTC){sub 2} reveal a high affinity of this material for the adsorption of carbon dioxide in the presence of nitrogen. (orig.)

Modelling interactions of carbon dioxide, forests, and climate

International Nuclear Information System (INIS)

Luxmoore, R.J.; Baldocchi, D.D.

1994-01-01

Atmospheric carbon dioxide is rising and forests and climate is changing exclamation point This combination of fact and premise may be evaluated at a range of temporal and spatial scales with the aid of computer simulators describing the interrelationships between forest vegetation, litter and soil characteristics, and appropriate meteorological variables. Some insights on the effects of climate on the transfers of carbon and the converse effect of carbon transfer on climate are discussed as a basis for assessing the significance of feedbacks between vegetation and climate under conditions of rising atmospheric carbon dioxide. Three main classes of forest models are reviewed. These are physiologically-based models, forest succession simulators based on the JABOWA model, and ecosystem-carbon budget models that use compartment transfer rates with empirically estimated coefficients. Some regression modeling approaches are also outlined. Energy budget models applied to forests and grasslands are also reviewed. This review presents examples of forest models; a comprehensive discussion of all available models is not undertaken

Multum in Parvo: Explorations with a Small Bag of Carbon Dioxide

Directory of Open Access Journals (Sweden)

EJM Campbell

2001-01-01

Full Text Available A collection of 12 papers published between 1957 and 1972 are revisited. The papers had a common theme of the use of rebreathing carbon dioxide and explored a variety of topics in respiratory physiology. The first study established a method for the noninvasive and indirect estimation of arterial carbon dioxide pressure that was suitable for the routine clinical monitoring of respiratory failure and whose clinical utility remains to this day, but which also provided observations that were the stimulus for the studies that followed. The rate of rise in the partial pressure of carbon dioxide (PCO2 during rebreathing led to an analysis of body carbon dioxide storage capacity. Knowledge of carbon dioxide storage led to a method for quantifying lactate production in exercise without the need for blood sampling. The changes in ventilation that accompanied the increase in PCO2 provided the basis for a rapid method for measuring aspects of breathing control (Read's method, which was later modified to measure the ventilatory response to hypoxia. The physiology of breath-holding was explored through observations of the fall in breath-holding time as PCO2 climbed. Rebreathing also allowed increases in voluntary ventilation to be achieved without the development of alkalosis, leading to studies of maximal voluntary ventilation and respiratory muscle fatigue. Equilibration of PCO2 during rebreathing was used to measure mixed venous PCO2 during exercise and develop an integrated approach to the physiology of exercise in health and disease; alveolar-arterial disequilibrium in PCO2 during exercise was uncovered. Equilibration of PCO2, as well as PO2, during rebreathing of carbon dioxide and nitrogen gas mixtures showed different time courses of venous gases at the onset of exercise. Starting with the rebreathing of carbon dioxide in oxygen mixtures in a small rubber bag, an astonishing range of topics in respiratory physiology was explored, with observations

POSSIBILITIES OF CARBON DIOXIDE FIXATION BY MICROALGAE IN REFINERY

OpenAIRE

Šingliar, Michal; Mikulec, Jozef; Kušnir, Patrik; Polakovičova, Gabriela

2013-01-01

Capture and sequestration of carbon dioxide is one of the most critical challenges today for businesses and governments worldwide. Thousands of emitting power plants and industries worldwide face this costly challenge – reduce the CO2 emissions or pay penalties. One possibility for carbon dioxide sequestration is its fixation in microalgae. Microalgae can sequester CO2 from flue gases emitted from fossil fuel-fired refinery plants and units, thereby reducing emissions of a major greenhouse ga...

Effects of elevated carbon dioxide concentration on growth and N2 fixation of young Robinia pseudoacacia

International Nuclear Information System (INIS)

Feng, Z; Flessa, H.; Dyckmans, J.

2004-01-01

The effects of elevated carbon dioxide concentration on carbon and nitrogen uptake and nitrogen source partitioning were determined in one year-old locust trees using a dual 13 C and 15 N continuous labelling experiment. Elevated carbon dioxide increased the fraction of new carbon in total carbon, but it did not alter carbon partitioning among plant compartments. Elevated carbon dioxide also increased the fraction of new nitrogen in total nitrogen. This was coupled with a shift in nitrogen source partitioning toward nitrogen fixation. Soil nitrogen uptake was not affected, but nitrogen fixation was markedly increased by elevated carbon dioxide treatment. The increased nitrogen fixation tended to decrease the C/N ratio in the presence of elevated carbon dioxide. Total dry mass of root nodules doubled in response to elevated carbon dioxide, however, this effect was not considered significant because of the great variability in root nodule formation. Overall, it was concluded that the growth of locust trees in an elevated carbon dioxide environment will not primarily be limited by nitrogen availability, giving the R. pseudoacacia species a competitive advantage over non-nitrogen-fixing tree species. It was also suggested that the increase in nitrogen fixation observed in response to elevated carbon dioxide treatment may play a key role in the growth response of forest ecosystems to elevated carbon dioxide by improving nitrogen availability for non-nitrogen-fixing trees. 51 refs., 1 tab., 4 figs

The carbon dioxide problem - a challenge to environmental protection

International Nuclear Information System (INIS)

Hlubek, W.; Spalthoff, F.J.

1989-01-01

Over the last century, man's activities on earth have sent off trace gases into the planet's atmosphere that have been concentrating to a level posing a threat to the global climate. Since scientists particularly spotted carbon dioxide as the main contributor to what we now call the greenhouse effect, there is urgent need for measures reducing carbon dioxide emission worldwide, may be on the basis of a global convention to be signed by both the industrialised and the developing countries. The industrialised countries, which certainly are the main pollutors, also will have the technological and financial resources to respond to the challenge of global warning more directly and faster than the developing countries. The power industry's management in the FRG is taking the problem seriously and has already come out with strategies for curbing carbon dioxide emissions from fossil-fuel power plant. (orig.) [de

Methane and Carbon Dioxide Emissions from Different Composting Periods

Directory of Open Access Journals (Sweden)

Cheng-Hsiung Chang

2009-01-01

Full Text Available To investigate green house gas emissions from compost preparations, methane and carbon dioxide concentrations and emission rates at different accumulative times and composting periods were determined. While the accumulative time was less than 10 min with a closed acrylic chamber, meth ane and carbon dioxide emissions in creased slightly but with high fluntuation in the sampling e ror, and these values decreased significantly when the accumulative time was more than 20 min. During the 8 weeks of composting, the methane emission rate reaches its peak near the end of the second week and the carbon dioxide emission rate does the same near the end of third week. Meth ane and carbon dioxide emissions had high val ues at the first stage of com post ing and then de creased grad u ally for the ma tu rity of com post. Carbon dioxide emission (y was significantly related to temperature (x1, moisture content (x2, and total or ganiccarbon (x3; and there gression equation is: y = 3.11907x1 + 6.19236x2 - 6.63081x3 - 50.62498. The re gres sion equa tion be tween meth ane emis sion (y? and mois ture con tent (x2, pH (x4, C/N ra tio (x5, and ash con tent (x6 is: y?= 0.13225x2 - 0.97046x4 - 1.10599x5 - 0.55220x6 + 50.77057 in the ini tial com post ing stage (weeks 1 to 3; while, the equa tion is: y?= 0.02824x2 - 0.0037x4 - 0.1499x5 - 0.07013x6 + 4.13589 in the later compost ing stage (weeks 4 to 8. Dif ferent stage composts have significant variation of properties and greenhouse gas emissions. Moreover, the emissions may be reduced by manipulating the proper factors.

Classroom Demonstration: Combustion of Diamond to Carbon Dioxide Followed by Reduction to Graphite

Science.gov (United States)

Miyauchi, Takuya; Kamata, Masahiro

2012-01-01

An educational demonstration shows the combustion of carbon to carbon dioxide and then the reduction of carbon dioxide to carbon. A melee diamond is the source of the carbon and the reaction is carried out in a closed flask. The demonstration helps students to realize that diamonds are made of carbon and that atoms do not change or vanish in…

Renewable Methane Generation from Carbon Dioxide and Sunlight.

Science.gov (United States)

Steinlechner, Christoph; Junge, Henrik

2018-01-02

The direct approach: Methane is a potential key player in the world's transition to a more sustainable energy future. The direct conversion of carbon dioxide into methane is highly desirable to lower the concentration of CO 2 in the atmosphere and also to store renewable energy. This Highlight describes the first homogeneous system for the light-driven conversion of CO 2 into CH 4 . © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Research on Urban Road Congestion Pricing Strategy Considering Carbon Dioxide Emissions

Directory of Open Access Journals (Sweden)

Yitian Wang

2015-08-01

Full Text Available Congestion pricing strategy has been recognized as an effective countermeasure in the practical field of urban traffic congestion mitigation. In this paper, a bi-level programming model considering carbon dioxide emission is proposed to mitigate traffic congestion and reduce carbon dioxide emissions. The objective function of the upper level model is to minimize the sum of travel costs and the carbon dioxide emissions costs. The lower level is a multi-modal transportation network equilibrium model. To solve the model, the method of successive averages (MSA and the shuffled frog leaping algorithm (SFLA are introduced. The proposed method and algorithm are tested through the numerical example. The results show that the proposed congestion pricing strategy can mitigate traffic congestion and reduce carbon emissions effectively.

Modeling carbon dioxide sequestration in saline aquifers: Significance of elevated pressures and salinities

International Nuclear Information System (INIS)

Allen, D.E.; Strazisar, B.R.; Soong, Y.; Hedges, S.W.

2005-01-01

The ultimate capacity of saline formations to sequester carbon dioxide by solubility and mineral trapping must be determined by simulating sequestration with geochemical models. These models, however, are only as reliable as the data and reaction scheme on which they are based. Several models have been used to make estimates of carbon dioxide solubility and mineral formation as a function of pressure and fluid composition. Intercomparison of modeling results indicates that failure to adjust all equilibrium constants to account for elevated carbon dioxide pressures results in significant errors in both solubility and mineral formation estimates. Absence of experimental data at high carbon dioxide pressures and high salinities make verification of model results difficult. Results indicate standalone solubility models that do not take mineral reactions into account will underestimate the total capacity of aquifers to sequester carbon dioxide in the long term through enhanced solubility and mineral trapping mechanisms. Overall, it is difficult to confidently predict the ultimate sequestration capacity of deep saline aquifers using geochemical models. (author)

Does Aerobic Respiration Produce Carbon Dioxide or Hydrogen Ion and Bicarbonate?

Science.gov (United States)

Swenson, Erik R

2018-05-01

Maintenance of intracellular pH is critical for clinical homeostasis. The metabolism of glucose, fatty acids, and amino acids yielding the generation of adenosine triphosphate in the mitochondria is accompanied by the production of acid in the Krebs cycle. Both the nature of this acidosis and the mechanism of its disposal have been argued by two investigators with a long-abiding interest in acid-base physiology. They offer different interpretations and views of the molecular mechanism of this intracellular pH regulation during normal metabolism. Dr. John Severinghaus has posited that hydrogen ion and bicarbonate are the direct end products in the Krebs cycle. In the late 1960s, he showed in brain and brain homogenate experiments that acetazolamide, a carbonic anhydrase inhibitor, reduces intracellular pH. This led him to conclude that hydrogen ion and bicarbonate are the end products, and the role of intracellular carbonic anhydrase is to rapidly generate diffusible carbon dioxide to minimize acidosis. Dr. Erik Swenson posits that carbon dioxide is a direct end product in the Krebs cycle, a more widely accepted view, and that acetazolamide prevents rapid intracellular bicarbonate formation, which can then codiffuse with carbon dioxide to the cell surface and there be reconverted for exit from the cell. Loss of this "facilitated diffusion of carbon dioxide" leads to intracellular acidosis as the still appreciable uncatalyzed rate of carbon dioxide hydration generates more protons. This review summarizes the available evidence and determines that resolution of this question will require more sophisticated measurements of intracellular pH with faster temporal resolution.

Preliminary study towards photoactivity enhancement using a biocompatible titanium dioxide/carbon nanotubes composite

International Nuclear Information System (INIS)

Cendrowski, Krzysztof; Jedrzejczak, Malgorzata; Peruzynska, Magdalena; Dybus, Andrzej; Drozdzik, Marek; Mijowska, Ewa

2014-01-01

Graphical abstract: Scheme demonstrating the experimental steps toward the formation of titania/multiwalled carbon nanotubes (TiO 2 -MWCNTs) from multiwalled carbon nanotubes (MWCNT). - Highlights: • Easy and efficient method of impregnation carbon nanotubes with titania. • High photoactivity. • Correlation between the interaction of carbon nanotubes with titania on the photocatalytic properties. • High biocompatibility of the nanotubes. - Abstract: Recent research is focused on the enhancement in photoactivity of titanium dioxide/carbon nanotubes through formation of novel nanocomposites that exhibit a high specific surface area, remarkable electron transfer and biocompatibility. Here, we explore a new synthesis route in the system composed of nanocrystalline titanium dioxide supported on external walls and inner space of multiwalled carbon nanotubes (MWCNT). The advantages of this method are: its simplicity, direct fusion of titanium dioxide particles on the carbon material, and formation of chemical bond Ti–O–C between TiO 2 and MWCNT. Photocatalytic performance of this system has been compared to a commercial catalyst (Degussa P25) in a model reaction of phenol decomposition in/under UV light. The efficiency of the process increased by the factor of 2.5 when the TiO 2 –MWCNT photocatalyst was utilized. Further, the photoactive nanocomposite was analysed towards its biocompatibility in order to establish a safe dose of the catalyst. Its influence on the cells viability was studied on mouse fibroblasts and human liver tissue cells, in the range from 0 to 100 μg/mL. This has revealed that the composite in concentrations up to 25 μg/mL exerted low toxicity, which allowed for finding a compromise between the highest safe dose and acceptable photoactivity of the catalyst

Chemoselective alternating copolymerization of limonene dioxide and carbon dioxide : a new highly functional aliphatic epoxy polycarbonate

NARCIS (Netherlands)

Li, C.; Sablong, R.J.; Koning, C.E.

The alternating copolymerization of biorenewable limonene dioxide with carbon dioxide (CO2) catalyzed by a zinc β-diiminate complex is reported. The chemoselective reaction results in linear amorphous polycarbonates that carry pendent methyloxiranes and exhibit glass transition temperatures (Tg) up

Carbon dioxide management by chemical conversion to methanol: HYDROGENATION and BI-REFORMING

International Nuclear Information System (INIS)

Wiesberg, Igor L.; Medeiros, José Luiz de; Alves, Rita M.B.; Coutinho, Paulo L.A.; Araújo, Ofélia Q.F.

2016-01-01

Highlights: • Evaluation of carbon dioxide conversion to methanol by two chemical routes. • HYDROGENATION: conversion via catalytic hydrogenation at high pressure. • BI-REFORMING: conversion via syngas from bi-reforming of natural gas. • HYDROGENATION is viable for hydrogen price inferior to 1000 US$/t. • BI-REFORMING is unable to avoid emissions; viable only if gas price is very low. - Abstract: Chemical conversion of carbon dioxide to methanol has the potential to address two relevant sustainability issues: economically feasible replacement of fossil raw materials and avoidance of greenhouse gas emissions. However, chemical stability of carbon dioxide is a challenging impediment to conversion requiring severe reaction conditions at the expense of increased energy input, therefore adding capital, operation and environmental costs, which could result in partial or total override of its potential sustainability as feedstock to the chemical and energy industries. This work investigates two innovative chemical destinations of carbon dioxide to methanol, namely a direct conversion through carbon dioxide hydrogenation (HYDROGENATION), and an indirect via carbon dioxide conversion to syngas through bi-reforming (BI-REFORMING). Process simulation is used to obtain mass and energy balances needed to support assessment of economic and environmental performance. A business scenario is considered where an industrial source of nearly pure carbon dioxide exists and an investment decision for utilization of carbon dioxide is faced. Due to uncertainties in prices of the raw materials, hydrogen (HYDROGENATION) and natural gas (BI-REFORMING), the decision procedure includes the definition of price thresholds to reach profitability. Sensitivity analyses are performed varying costs with greater uncertainty, i.e., carbon dioxide and methanol, and recalculating maximum allowable prices of raw materials. The analyses show that in a Brazilian scenario, BI-REFORMING is unlikely

Can carbon dioxide storage help cut greenhouse emissions? A simplified guide to the IPCC's 'Special Report on Carbon Dioxide Capture and Storage'

International Nuclear Information System (INIS)

2006-06-01

Fossil fuels account for 75 - 80% of today's global energy use and three quarters of humanity's total carbon dioxide emissions. Without specific actions to minimize our impact on the climate, carbon dioxide (CO2) emissions from fossil-fuel energy are projected to swell over the course of the 21st century. The consequences - a global temperature rise of 1.4 - 5.8C and shifting patterns of weather and extreme events - could prove disastrous for future generations. Stabilizing or reducing global emissions of carbon dioxide and other greenhouse gases over the coming decades will challenge human ingenuity. Fortunately, the IPCC's Third Assessment Report, published in 2001, concluded that existing and emerging technologies for limiting emissions could - if supported by the right policies - stabilize atmospheric concentrations of greenhouse gases by the end of the century at levels that would limit further climate change. No single technology will suffice by itself; instead, a combination of technologies will be required. Many of the most promising technologies will contribute by improving the energy efficiency of certain processes and products or by converting solar, wind and other noncarbon power sources into usable energy. But with oil, coal and gas set to remain the primary sources of energy for decades to come, governments and industry are also examining technologies for reducing emissions from these fuels. One such technology is known as carbon dioxide capture and storage. Abbreviated as CCS, this technology could be used by large c1 Introduction stationary 'point sources' such as fossil fuel-fired power plants and industrial facilities to prevent their CO2 emissions from entering the atmosphere and contributing to climate change. To learn more about this technology's potential, the member governments of the United Nations Framework Convention on Climate Change asked the IPCC to assess the current state of knowledge about carbon dioxide storage and capture. The IPCC

Sintering uranium oxide in the reaction product of hydrogen-carbon dioxide mixtures

International Nuclear Information System (INIS)

De Hollander, W.R.; Nivas, Y.

1975-01-01

Compacted pellets of uranium oxide alone or containing one or more additives such as plutonium dioxide, gadolinium oxide, titanium dioxide, silica, and alumina are heated to 900 to 1599 0 C in the presence of a mixture of hydrogen and carbon dioxide, either alone or with an inert carrier gas and held at the desired temperature in this atmosphere to sinter the pellets. The sintered pellets are then cooled in an atmosphere having an oxygen partial pressure of 10 -4 to 10 -18 atm of oxygen such as dry hydrogen, wet hydrogen, dry carbon monoxide, wet carbon monoxide, inert gases such as nitrogen, argon, helium, and neon and mixtures of ayny of the foregoing including a mixture of hydrogen and carbon dioxide. The ratio of hydrogen to carbon dioxide in the gas mixture fed to the furnace is controlled to give a ratio of oxygen to uranium atoms in the sintered particles within the range of 1.98:1 to about 2.10:1. The water vapor present in the reaction products in the furnace atmosphere acts as a hydrolysis agent to aid removal of fluoride should such impurity be present in the uranium oxide. (U.S.)

75 FR 75059 - Mandatory Reporting of Greenhouse Gases: Injection and Geologic Sequestration of Carbon Dioxide

Science.gov (United States)

2010-12-01