WorldWideScience

Sample records for adsorbed hydrogen technical

  1. Rate inhibition of steam gasification of adsorbed hydrogen. Technical progress report, October 1, 1994--December 31, 1994

    Energy Technology Data Exchange (ETDEWEB)

    Miller, D.J.

    1995-04-01

    Work during the fifth quarter of the grant period has involved both gasification experiments in steam and hydrogen and continued development of the reaction apparatus and analytical methods. Most of the latter work has focused on mass spectrometric analysis of the effluent gases to obtain better response factors and to reduce background signals resulting from impurities in the reacting gas stream.

  2. Hydrogen Delivery Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    The mission of the Hydrogen Delivery Technical Team (HDTT) is to enable the development of hydrogen delivery technologies, which will allow for fuel cell competitiveness with gasoline and hybrid technologies by achieving an as-produced, delivered, and dispensed hydrogen cost of $2-$4 per gallon of gasoline equivalent of hydrogen.

  3. Hydrogen Storage Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    The mission of the Hydrogen Storage Technical Team is to accelerate research and innovation that will lead to commercially viable hydrogen-storage technologies that meet the U.S. DRIVE Partnership goals.

  4. Low Pressure Adsorbent for Recovery & Storage Vented Hydrogen, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — A high performance fullerene-based adsorbent is proposed for recovery and storage hydrogen and separating helium via pressure-swing-adsorption (PSA) process....

  5. Hydrogen molecule on lithium adsorbed graphene: A DFT study

    International Nuclear Information System (INIS)

    Kaur, Gagandeep; Gupta, Shuchi; Gaganpreet; Dharamvir, Keya

    2016-01-01

    Electronic structure calculations for the adsorption of molecular hydrogen on lithium (Li) decorated and pristine graphene have been studied systematically using SIESTA code [1] within the framework of the first-principle DFT under the Perdew-Burke-Ernzerhof (PBE) form of the generalized gradient approximation (GGA)[2], including spin polarization. The energy of adsorption of hydrogen molecule on graphene is always enhanced by the presence of co-adsorbed lithium. The most efficient adsorption configuration is when H 2 is lying parallel to lithium adsorbed graphene which is in contrast to its adsorption on pristine graphene (PG) where it prefers perpendicular orientation.

  6. Interaction of atomic hydrogen with ethylene adsorbed on nickel films

    International Nuclear Information System (INIS)

    Korchak, V.N.; Tret'yakov, I.I.; Kislyuk, M.U.

    1976-01-01

    The reactivity of ethylene adsorbed on the pure films of nickel at various temperatures was studied with respect to hydrogen atoms generated in the gaseous phase. The experiments were conducted in a glass vacuum apparatus enabling one to obtain the highest vacuum up to 2x20 -10 torr. The catalyst, nickel films, was produced by their deposition onto the walls of the glass reactor at a pressure of the residual gas of 10 -9 torr and a temperature of the walls of 25 deg C. Gas purity was analyzed by the mass spectrometric method. The ethylene adsorbed at the temperatures below 173 deg K reacted readily with the hydrogen atoms to yield ethane. The process ran without practically any activation energy involved and was limited by the attachment of the first hydrogen atom to the ethylene molecule. The efficiency of this interaction was 0.02 of the number of the hydrogen atoms collisions against the surface occupied by the ethylene. The adsorption of the ethylene at room and higher temperatures was accompanied by its disproportioning with the release of the hydrogen into the gaseous phase and a serious destruction of the ethylene molecules adsorbed to produce hydrogen residues interacting with neither molecular nor atomic hydrogen [ru

  7. Hydrogen Production Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    The Hydrogen Production Technical Team Roadmap identifies research pathways leading to hydrogen production technologies that produce near-zero net greenhouse gas (GHG) emissions from highly efficient and diverse renewable energy sources. This roadmap focuses on initial development of the technologies, identifies their gaps and barriers, and describes activities by various U.S. Department of Energy (DOE) offices to address the key issues and challenges.

  8. Adsorption removal of hydrogen sulfide gas. IV. Characteristics of adsorbents for the adsorption removal of hydrogen sulfide gas

    Energy Technology Data Exchange (ETDEWEB)

    Boki, K

    1974-10-25

    The amount of hydrogen sulfide gas adsorbed was affected by the surface properties (surface pH, acid strength, acid amount, and basic amount), the surface structure (pore volume), and the surface form (scanning electron microscopic observation) of 32 tested adsorbents. In general, the amount adsorption increased in the following order, amount of H/sub 2/S adsorbed on the silicate adsorbents, on the active carbon adsorbents, and on the zeolite adsorbents. The amount of H/sub 2/S adsorbed on magnesium silicate and silica gel adsorbents was mainly affected by the surface structure, and the amount adsorbed on the aluminum silicate adsorbents was affected by the distinctions on the surface forms of the adsorbents. The amount of H/sub 2/S adsorbed on 10 kinds of active carbon was determined by the surface properties and the surface structures of the adsorbents. The amount adsorbed on 12 kinds of zeolites was determined by either the surface properties or by the surface structures of the adsorbents. The amount of H/sub 2/S adsorbed on the silicate, active carbon, and zeolite adsorbents interacted with the heat of adsorption, and among the same kinds of adsorbents, the amount adsorbed was linearly related to the heat of adsorption.

  9. A COMPREHENSIVE STUDY OF HYDROGEN ADSORBING TO AMORPHOUS WATER ICE: DEFINING ADSORPTION IN CLASSICAL MOLECULAR DYNAMICS

    Energy Technology Data Exchange (ETDEWEB)

    Dupuy, John L.; Lewis, Steven P.; Stancil, P. C. [Department of Physics and Astronomy and the Center for Simulational Physics, University of Georgia, Athens, GA 30602 (United States)

    2016-11-01

    Gas–grain and gas–phase reactions dominate the formation of molecules in the interstellar medium (ISM). Gas–grain reactions require a substrate (e.g., a dust or ice grain) on which the reaction is able to occur. The formation of molecular hydrogen (H{sub 2}) in the ISM is the prototypical example of a gas–grain reaction. In these reactions, an atom of hydrogen will strike a surface, stick to it, and diffuse across it. When it encounters another adsorbed hydrogen atom, the two can react to form molecular hydrogen and then be ejected from the surface by the energy released in the reaction. We perform in-depth classical molecular dynamics simulations of hydrogen atoms interacting with an amorphous water-ice surface. This study focuses on the first step in the formation process; the sticking of the hydrogen atom to the substrate. We find that careful attention must be paid in dealing with the ambiguities in defining a sticking event. The technical definition of a sticking event will affect the computed sticking probabilities and coefficients. Here, using our new definition of a sticking event, we report sticking probabilities and sticking coefficients for nine different incident kinetic energies of hydrogen atoms [5–400 K] across seven different temperatures of dust grains [10–70 K]. We find that probabilities and coefficients vary both as a function of grain temperature and incident kinetic energy over the range of 0.99–0.22.

  10. Influence of adsorbed carbon dioxide on hydrogen electrosorption in palladium-platinum-rhodium alloys

    International Nuclear Information System (INIS)

    Lukaszewski, M.; Grden, M.; Czerwinski, A.

    2004-01-01

    Carbon dioxide electroreduction was applied to examine the processes of hydrogen electrosorption (adsorption, absorption and desorption) by thin electrodeposits of Pd-Pt-Rh alloys under conditions of cyclic voltammetric (CV) experiments. Due to different adsorption characteristics towards the adsorption product of the electroreduction of CO 2 (reduced CO 2 ) exhibited by the alloy components hydrogen adsorption and hydrogen absorption signals can be distinguished on CV curves. Reduced CO 2 causes partial blocking of hydrogen adsorbed on surface Pt and Rh atoms, without any significant effect on hydrogen absorption into alloy. It reflects the fact that adsorbed hydrogen bonded to Pd atoms does not participate in CO 2 reduction, while hydrogen adsorbed on Pt and Rh surface sites is inactive in the absorption reaction. In contrast, CO is adsorbed on all alloy components and causes a marked inhibition of hydrogen sorption (both adsorption and absorption)/desorption reactions

  11. Creation of the technical adsorbent from local raw materials

    International Nuclear Information System (INIS)

    Isobaev, M.D.; Davlatnazarova, M.D.; Abdullaev, T.H.

    2016-01-01

    The results showed the possibility of obtaining effective adsorbents of walnut shell and the sunflower for environmental purposes, in particular for the purification of polluted waters from heavy metals. It has been shown, that 1 g of walnut shell adsorbent can adsorb on its surface ions of lead in amount of 47% by weight. The dependence of the adsorption activity of the semi-coke received from walnut shell from particle size and concentration of the solution. (author)

  12. Technical Analysis of Hydrogen Production

    Energy Technology Data Exchange (ETDEWEB)

    Ali T-Raissi

    2005-01-14

    The aim of this work was to assess issues of cost, and performance associated with the production and storage of hydrogen via following three feedstocks: sub-quality natural gas (SQNG), ammonia (NH{sub 3}), and water. Three technology areas were considered: (1) Hydrogen production utilizing SQNG resources, (2) Hydrogen storage in ammonia and amine-borane complexes for fuel cell applications, and (3) Hydrogen from solar thermochemical cycles for splitting water. This report summarizes our findings with the following objectives: Technoeconomic analysis of the feasibility of the technology areas 1-3; Evaluation of the hydrogen production cost by technology areas 1; and Feasibility of ammonia and/or amine-borane complexes (technology areas 2) as a means of hydrogen storage on-board fuel cell powered vehicles. For each technology area, we reviewed the open literature with respect to the following criteria: process efficiency, cost, safety, and ease of implementation and impact of the latest materials innovations, if any. We employed various process analysis platforms including FactSage chemical equilibrium software and Aspen Technologies AspenPlus and HYSYS chemical process simulation programs for determining the performance of the prospective hydrogen production processes.

  13. Solid adsorbents for removal of hydrogen sulphide from hot gas

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; Yumura, Motoo

    1986-04-01

    A wide range of solids have been tested as potential adsorbents for H/sub 2/S removal from hot gas. These solids can be divided into two main groups, i.e., the adsorbents containing alkaline earth metals and those containing transition metals. Among the former, calcium oxide and naturally occurring materials such as limestone, dolomite and calcium silicate have attracted a great deal of attention. The adsorbents of the second group include iron oxide alone or in combination with some supports, zinc oxide, zinc ferrite and manganese oxide. The materials containing both the alkaline earth metals and transition metals, e.g., manganese nodules, fly ash and the reject from the aluminium industry (red mud) have been evaluated as well.

  14. Technical and economic analysis of hydrogen refuelling

    International Nuclear Information System (INIS)

    Nistor, Silviu; Dave, Saraansh; Fan, Zhong; Sooriyabandara, Mahesh

    2016-01-01

    Highlights: • Technical and economic models of a hydrogen station for vehicles refuelling. • Hydrogen demand from fuel cell electric vehicles modelled stochastically. • Study case based on a UK pilot project. • Operation of the H_2 station using combined energy from wind and power grid is preferred. • Return on investment of 5–10 years is possible for the hydrogen station. - Abstract: This paper focuses on technical and economic analysis of a hydrogen refilling station to provide operational insight through tight coupling of technical models of physical processes and economic models. This allows the dynamic relationships of the system to be captured and analysed to provide short/medium term analytical capability to support system design, planning, and financing. The modelling developed here highlights the need to closely link technical and economic models for technology led projects where technical capability and commercial feasibility are important. The results show that hydrogen fuel can be competitive with petrol on a GBP/KG basis if the return on investment period is over 10 years for PEM electrolysers and 5 for Alkaline electrolysers. We also show that subsidies on capital costs (as reflected by some R&D funding programs) make both PEM and Alkaline technologies cheaper than the equivalent price of petrol, which suggests more emphasis should be put on commercialising R&D funded projects as they have commercial advantages. The paper also shows that a combined wind and grid connected station is preferable so that a higher number of customers are served (i.e. minimum shortage of hydrogen).

  15. Electrochemical titration of hydrogen adsorbed on supported platinum catalysts

    Czech Academy of Sciences Publication Activity Database

    Paseka, Ivo

    2007-01-01

    Roč. 329, - (2007), s. 161-163 ISSN 0926-860X R&D Projects: GA ČR GA104/03/0409 Institutional research plan: CEZ:AV0Z40320502 Keywords : platinum * hydrogen adsorption * specific surface area Subject RIV: CA - Inorganic Chemistry Impact factor: 3.166, year: 2007

  16. Hydrogen Technical Analysis -- Dissemination of Information

    Energy Technology Data Exchange (ETDEWEB)

    George Kervitsky, Jr.

    2006-03-20

    SENTECH is a small energy and environmental consulting firm providing technical, analytical, and communications solutions to technology management issues. The activities proposed by SENTECH focused on gathering and developing communications materials and information, and various dissemination activities to present the benefits of hydrogen energy to a broad audience while at the same time establishing permanent communications channels to enable continued two-way dialog with these audiences in future years. Effective communications and information dissemination is critical to the acceptance of new technology. Hydrogen technologies face the additional challenge of safety preconceptions formed primarily as a result of the crash of the Hindenburg. Effective communications play a key role in all aspects of human interaction, and will help to overcome the perceptual barriers, whether of safety, economics, or benefits. As originally proposed SENTECH identified three distinct information dissemination activities to address three distinct but important audiences; these formed the basis for the task structure used in phases 1 and 2. The tasks were: (1) Print information--Brochures that target the certain segment of the population and will be distributed via relevant technical conferences and traditional distribution channels. (2) Face-to-face meetings--With industries identified to have a stake in hydrogen energy. The three industry audiences are architect/engineering firms, renewable energy firms, and energy companies that have not made a commitment to hydrogen (3) Educational Forums--The final audience is students--the future engineers, technicians, and energy consumers. SENTECH will expand on its previous educational work in this area. The communications activities proposed by SENTECH and completed as a result of this cooperative agreement was designed to compliment the research and development work funded by the DOE by presenting the technical achievements and validations

  17. Technical Integration of Nuclear Hydrogen Production Technology

    International Nuclear Information System (INIS)

    Lee, Ki Young; Park, J. K.; Chang, J. H.

    2009-04-01

    These works focus on the development of attainment indices for nuclear hydrogen key technologies, the analysis of the hydrogen production process and the performance estimation for hydrogen production systems, and the assessment of the nuclear hydrogen production cost. For assessing the degree of attainments in comparison with the final goals of VHTR technologies in progress of researches, subdivided are the prerequisite items confirmed to the NHDD concepts. We developed and applied R and D quality management methodology to meet 'Development of Key Technologies for Nuclear Hydrogen' project. And we also distributed R and D QAM and R and D QAP to each teams and are in operation. The preconceptual flow diagrams of SI, HTSE, and HyS processes are introduced and their material and energy balances have been proposed. The hydrogen production thermal efficiencies of not only the SI process as a reference process but also the HTSE and HyS processes were also estimated. Technical feasibility assessments of SI, HTSE, and HyS processes have been carried out by using the pair-wise comparison and analytic hierarchy process, and it is revealed that the experts are considering the SI process as the most feasible process. The secondary helium pathway across the SI process is introduced. Dynamic simulation codes for the H2S04vaporizer, sulfuric acid and sulfur trioxide decomposers, and HI decomposer on the secondary helium pathway and for the primary and secondary sulfuric acid distillation columns, HIx solution distillation column, and preheater for HI vapor have been developed and integrated

  18. A lumped-parameter model for cryo-adsorber hydrogen storage tank

    Energy Technology Data Exchange (ETDEWEB)

    Senthil Kumar, V.; Raghunathan, K. [India Science Lab, General Motors R and D, Creator Building, International Technology Park, Bangalore 560066 (India); Kumar, Sudarshan [Chemical and Environmental Sciences Lab, General Motors R and D, 30500 Mound Road, Warren, MI 48090 (United States)

    2009-07-15

    One of the primary requirements for commercialization of hydrogen fuel-cell vehicles is the on-board storage of hydrogen in sufficient quantities. On-board storage of hydrogen by adsorption on nano-porous adsorbents at around liquid nitrogen temperatures and moderate pressures is considered viable and competitive with other storage technologies: liquid hydrogen, compressed gas, and metallic or complex hydrides. The four cryo-adsorber fuel tank processes occur over different time scales: refueling over a few minutes, discharge over a few hours, dormancy over a few days, and venting over a few weeks. The slower processes i.e. discharge, dormancy and venting are expected to have negligible temperature gradients within the bed, and hence are amenable to a lumped-parameter analysis. Here we report a quasi-static lumped-parameter model for the cryo-adsorber fuel tank, and discuss the results for these slower processes. We also describe an alternative solution method for dormancy and venting based on the thermodynamic state description. (author)

  19. 77 FR 50488 - Hydrogen and Fuel Cell Technical Advisory Committee

    Science.gov (United States)

    2012-08-21

    ... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee AGENCY: Department of...). SUMMARY: This notice announces an open meeting (Webinar) of the Hydrogen and Fuel Cell Technical Advisory... Avenue, Washington, DC 20585. SUPPLEMENTARY INFORMATION: Purpose of the Committee: The Hydrogen and Fuel...

  20. Decontamination of adsorbed chemical warfare agents on activated carbon using hydrogen peroxide solutions.

    Science.gov (United States)

    Osovsky, Ruth; Kaplan, Doron; Nir, Ido; Rotter, Hadar; Elisha, Shmuel; Columbus, Ishay

    2014-09-16

    Mild treatment with hydrogen peroxide solutions (3-30%) efficiently decomposes adsorbed chemical warfare agents (CWAs) on microporous activated carbons used in protective garments and air filters. Better than 95% decomposition of adsorbed sulfur mustard (HD), sarin, and VX was achieved at ambient temperatures within 1-24 h, depending on the H2O2 concentration. HD was oxidized to the nontoxic HD-sulfoxide. The nerve agents were perhydrolyzed to the respective nontoxic methylphosphonic acids. The relative rapidity of the oxidation and perhydrolysis under these conditions is attributed to the microenvironment of the micropores. Apparently, the reactions are favored due to basic sites on the carbon surface. Our findings suggest a potential environmentally friendly route for decontamination of adsorbed CWAs, using H2O2 without the need of cosolvents or activators.

  1. Hydrogen bond dynamical properties of adsorbed liquid water monolayers with various TiO2 interfaces

    Science.gov (United States)

    English, Niall J.; Kavathekar, Ritwik S.; MacElroy, J. M. D.

    2012-12-01

    Equilibrium classical molecular dynamics (MD) simulations have been performed to investigate the hydrogen-bonding kinetics of water in contact with rutile-(110), rutile-(101), rutile-(100), and anatase-(101) surfaces at room temperature (300 K). It was observed that anatase-(101) exhibits the longest-lived hydrogen bonds in terms of overall persistence, followed closely by rutile-(110). The relaxation times, defined as the integral of the autocorrelation of the hydrogen bond persistence function, were also longer for these two cases, while decay of the autocorrelation function was slower. The increased number and overall persistence of hydrogen bonds in the adsorbed water monolayers at these surfaces, particularly for anatase-(101), may serve to promote possible water photolysis activity thereon.

  2. Surface atomic relaxation and magnetism on hydrogen-adsorbed Fe(110) surfaces from first principles

    Science.gov (United States)

    Chohan, Urslaan K.; Jimenez-Melero, Enrique; Koehler, Sven P. K.

    2016-11-01

    We have computed adsorption energies, vibrational frequencies, surface relaxation and buckling for hydrogen adsorbed on a body-centred-cubic Fe(110) surface as a function of the degree of H coverage. This adsorption system is important in a variety of technological processes such as the hydrogen embrittlement in ferritic steels, which motivated this work, and the Haber-Bosch process. We employed spin-polarised density functional theory to optimise geometries of a six-layer Fe slab, followed by frozen mode finite displacement phonon calculations to compute Fe-H vibrational frequencies. We have found that the quasi-threefold (3f) site is the most stable adsorption site, with adsorption energies of ∼3.0 eV/H for all coverages studied. The long-bridge (lb) site, which is close in energy to the 3f site, is actually a transition state leading to the stable 3f site. The calculated harmonic vibrational frequencies collectively span from 730 to 1220 cm-1, for a range of coverages. The increased first-to-second layer spacing in the presence of adsorbed hydrogen, and the pronounced buckling observed in the Fe surface layer, may facilitate the diffusion of hydrogen atoms into the bulk, and therefore impact the early stages of hydrogen embrittlement in steels.

  3. Surface atomic relaxation and magnetism on hydrogen-adsorbed Fe(110) surfaces from first principles

    Energy Technology Data Exchange (ETDEWEB)

    Chohan, Urslaan K.; Jimenez-Melero, Enrique [School of Materials, The University of Manchester, Manchester M13 9PL (United Kingdom); Dalton Cumbrian Facility, The University of Manchester, Moor Row CA24 3HA (United Kingdom); Koehler, Sven P.K., E-mail: sven.koehler@manchester.ac.uk [Dalton Cumbrian Facility, The University of Manchester, Moor Row CA24 3HA (United Kingdom); School of Chemistry, The University of Manchester, Manchester M13 9PL (United Kingdom); Photon Science Institute, The University of Manchester, Manchester M13 9PL (United Kingdom)

    2016-11-30

    Highlights: • Potential energy surfaces for H diffusion on Fe(110) calculated. • Full vibrational analysis of surface modes performed. • Vibrational analysis establishes lb site as a transition state to the 3f site. • Pronounced buckling observed in the Fe surface layer. - Abstract: We have computed adsorption energies, vibrational frequencies, surface relaxation and buckling for hydrogen adsorbed on a body-centred-cubic Fe(110) surface as a function of the degree of H coverage. This adsorption system is important in a variety of technological processes such as the hydrogen embrittlement in ferritic steels, which motivated this work, and the Haber–Bosch process. We employed spin-polarised density functional theory to optimise geometries of a six-layer Fe slab, followed by frozen mode finite displacement phonon calculations to compute Fe–H vibrational frequencies. We have found that the quasi-threefold (3f) site is the most stable adsorption site, with adsorption energies of ∼3.0 eV/H for all coverages studied. The long-bridge (lb) site, which is close in energy to the 3f site, is actually a transition state leading to the stable 3f site. The calculated harmonic vibrational frequencies collectively span from 730 to 1220 cm{sup −1}, for a range of coverages. The increased first-to-second layer spacing in the presence of adsorbed hydrogen, and the pronounced buckling observed in the Fe surface layer, may facilitate the diffusion of hydrogen atoms into the bulk, and therefore impact the early stages of hydrogen embrittlement in steels.

  4. Extremely short optical pulse in a system of nanotubes with adsorbed hydrogen

    International Nuclear Information System (INIS)

    Belonenko, Mikhail B.; Popov, Alexander S.; Lebedev, Nikolay G.; Pak, Anastasia V.; Zhukov, Alexander V.

    2011-01-01

    In this Letter we address the system of carbon nanotubes with adsorbed hydrogen, which is a problem of particular practical importance. Based on the periodic Anderson model we describe the electronic subsystem in such a system, so that employing the method of Green functions allowed us to obtain the dispersion law for electrons. In the low-temperature limit we investigated a joint dynamics of electrons and electromagnetic field. The effective equation, which describes the propagation of ultrashort optical pulses, has been derived. We analyze the solutions of this equation and their dependence on the parameters of the problem for a two-dimensional CNT system.

  5. Optimization of the elaboration conditions of an adsorber for the hydrogen storage; Optimisation des conditions d'elaboration d'un adsorbant pour le stockage d'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    Fierro, V.; Mareche, J.F.; Furdin, G. [Nancy-1 Univ. Henri Poincare, UMR - CNRS 7555, Laboratoire de Chimie du Solide Mineral, 54 - Vandoeuvre-les-Nancy (France); Szczurek, A.; Albiniak, A. [Wroclaw Univ. of Technology, Laboratory for Lignites and Carbon Adsorbents, Institute of Chemistry and Technology of Petroleum and Coal (Poland); Latroche, M. [Chimie Metallurgique des Terres Rares, ICMPE, UMR 7182, CNRS, 94 - Thiais (France); Celzard, A. [Nancy-Univ., ENSTIB, Laboratoire de Chimie du Solide Mineral, UMR CNRS 7555, 88 - Epinal (France)

    2008-07-01

    The microporous carbon are very efficient adsorbents for the hydrogen storage, because of pores size under 2 nm. This study describes the optimization of the elaboration conditions for a carbon adsorbent for the hydrogen storage by adsorption. The storage capacity has been measured at 25 C for 20 MPa and also at 77 K for pressures between 6 and 9 MPa. the porous texture characterization has been realized by four molecule probes of increasing diameter: CO{sub 2}, N{sub 2}, C{sub 6}H{sub 6} and CCl{sub 4}. (A.L.B.)

  6. Influence of adsorbed hydrogen molecules on the hydrogen permeation and recycling

    International Nuclear Information System (INIS)

    Banno, T.

    1987-01-01

    Hydrogen permeation through a thin iron membrane has been measured using a molecular hydrogen gas and/or a weakly ionized rf-discharge as particle sources. Transient and steady state values of the permeation flux φ p were obtained in the regime where the surface penetration of H and the recombinative release of H 2 are rate-determining. φ p is then proportional to the flux density ψ of the particles which impinge on the membrane upstream. The proportionality factors depend on the nature (atomic or molecular) of the incident particles, on temperature (in particular for a molecular driving gas) and on the ratio of the surface recombinative release rate constants (2σk r ) u and (2σk r ) d up- and downstream, respectively. (orig.)

  7. Work function dependence and isotope effect in the production of negative hydrogen ions during sputtering of adsorbed hydrogen on Cs covered Mo(100) surfaces

    International Nuclear Information System (INIS)

    Yu, M.L.

    1977-01-01

    The enhancement of the H - yield, during sputtering of adsorbed hydrogen on a Mo(100) surface, by a Cs overlayer was investigated. An exponential dependence of the H - yield on the work function was observed for a wide range of Cs coverages. A simple electron tunneling model was proposed. A large reduction in the ion yield was also observed when D 2 replaced H 2 as the adsorbate

  8. Technical suitability mapping of feedstocks for biological hydrogen production

    NARCIS (Netherlands)

    Panagiotopoulos, I.A.; Karaoglanoglou, L.S.; Koullas, D.P.; Bakker, R.R.; Claassen, P.A.M.; Koukios, E.G.

    2015-01-01

    The objective of this work was to map and compare the technical suitability of different raw materials for biological hydrogen production. Our model was based on hydrogen yield potential, sugar mobilization efficiency, fermentability and coproduct yield and value. The suitability of the studied

  9. Technical Integration of Nuclear Hydrogen Production Technology

    International Nuclear Information System (INIS)

    Lee, Ki Young; Chang, J. H.; Park, J. K.

    2007-06-01

    These works focus on the development of attainment indices for nuclear hydrogen key technologies, the analysis of the hydrogen production process and the performance estimation for hydrogen production system, and the assessment of the nuclear hydrogen production economy. To estimate the attainments of the key technologies in progress with the performance goals of GIF, itemized are the attainment indices based on SRP published in VHTR R and D steering committee of Gen-IV. For assessing the degree of attainments in comparison with the final goals of VHTR technologies in progress of researches, subdivided are the prerequisite items conformed to the NHDD concepts established in a preconceptual design in 2005. The codes for analyzing the hydrogen production economy are developed for calculating the unit production cost of nuclear hydrogen. We developed basic R and D quality management methodology to meet design technology of VHTR's needs. By putting it in practice, we derived some problems and solutions. We distributed R and D QAP and Q and D QAM to each teams and these are in operation. Computer simulations are performed for estimating the thermal efficiency for the electrodialysis component likely to adapting as one of the hydrogen production system in Korea and EED-SI process known as the key components of the hydrogen production systems. Using the commercial codes, the process diagrams and the spread-sheets were produced for the Bunsen reaction process, Sulphuric Acid dissolution process and HI dissolution process, respectively, which are the key components composing of the SI process

  10. Revisiting the inelastic electron tunneling spectroscopy of single hydrogen atom adsorbed on the Cu(100) surface

    International Nuclear Information System (INIS)

    Jiang, Zhuoling; Wang, Hao; Sanvito, Stefano; Hou, Shimin

    2015-01-01

    Inelastic electron tunneling spectroscopy (IETS) of a single hydrogen atom on the Cu(100) surface in a scanning tunneling microscopy (STM) configuration has been investigated by employing the non-equilibrium Green’s function formalism combined with density functional theory. The electron-vibration interaction is treated at the level of lowest order expansion. Our calculations show that the single peak observed in the previous STM-IETS experiments is dominated by the perpendicular mode of the adsorbed H atom, while the parallel one only makes a negligible contribution even when the STM tip is laterally displaced from the top position of the H atom. This propensity of the IETS is deeply rooted in the symmetry of the vibrational modes and the characteristics of the conduction channel of the Cu-H-Cu tunneling junction, which is mainly composed of the 4s and 4p z atomic orbitals of the Cu apex atom and the 1s orbital of the adsorbed H atom. These findings are helpful for deepening our understanding of the propensity rules for IETS and promoting IETS as a more popular spectroscopic tool for molecular devices

  11. Heat capacity of quantum adsorbates: Hydrogen and helium on evaporated gold films

    International Nuclear Information System (INIS)

    Birmingham, J.T.; Lawrence Berkeley National Lab., CA

    1996-06-01

    The author has constructed an apparatus to make specific heat measurements of quantum gases adsorbed on metallic films at temperatures between 0.3 and 4 K. He has used this apparatus to study quench-condensed hydrogen films between 4 and 923 layers thick with J = 1 concentrations between 0.28 and 0.75 deposited on an evaporated gold surface. He has observed that the orientational ordering of the J = 1 molecules depends on the substrate temperature during deposition of the hydrogen film. He has inferred that the density of the films condensed at the lowest temperatures is 25% higher than in bulk H 2 crystals and have observed that the structure of those films is affected by annealing at 3.4 K. The author has measured the J = 1 to J = 0 conversion rate to be comparable to that of the bulk for thick films; however, he found evidence that the gold surface catalyzes conversion in the first two to four layers. He has also used this apparatus to study films of 4 He less than one layer thick adsorbed on an evaporated gold surface. He shows that the phase diagram of the system is similar to that for 4 He/graphite although not as rich in structure, and the phase boundaries occur at different coverages and temperatures. At coverages below about half a layer and at sufficiently high temperatures, the 4 He behaves like a two-dimensional noninteracting Bose gas. At lower temperatures and higher coverages, liquidlike and solidlike behavior is observed. The Appendix shows measurements of the far-infrared absorptivity of the high-T c superconductor La 1.87 Sr 0.13 CuO 4

  12. Final Technical Report: Hydrogen Codes and Standards Outreach

    Energy Technology Data Exchange (ETDEWEB)

    Hall, Karen I.

    2007-05-12

    This project contributed significantly to the development of new codes and standards, both domestically and internationally. The NHA collaborated with codes and standards development organizations to identify technical areas of expertise that would be required to produce the codes and standards that industry and DOE felt were required to facilitate commercialization of hydrogen and fuel cell technologies and infrastructure. NHA staff participated directly in technical committees and working groups where issues could be discussed with the appropriate industry groups. In other cases, the NHA recommended specific industry experts to serve on technical committees and working groups where the need for this specific industry expertise would be on-going, and where this approach was likely to contribute to timely completion of the effort. The project also facilitated dialog between codes and standards development organizations, hydrogen and fuel cell experts, the government and national labs, researchers, code officials, industry associations, as well as the public regarding the timeframes for needed codes and standards, industry consensus on technical issues, procedures for implementing changes, and general principles of hydrogen safety. The project facilitated hands-on learning, as participants in several NHA workshops and technical meetings were able to experience hydrogen vehicles, witness hydrogen refueling demonstrations, see metal hydride storage cartridges in operation, and view other hydrogen energy products.

  13. Comment on "Theoretical study of the dynamics of atomic hydrogen adsorbed on graphene multilayers"

    Science.gov (United States)

    Bonfanti, Matteo; Martinazzo, Rocco

    2018-03-01

    It is shown that the theoretical prediction of a transient magnetization in bilayer and multilayer graphene (M. Moaied et al., Phys. Rev. B 91, 155419 (2015), 10.1103/PhysRevB.91.155419) relies on an incorrect physical scenario for adsorption, namely, one in which H atoms adsorb barrierless on graphitic substrates and form a random adsorption pattern of monomers. Rather, according to experimental evidence, H atom sticking is an activated process, and adsorption is under kinetic control, largely ruled by a preferential sticking mechanism that leads to stable, nonmagnetic dimers at all but the smallest coverages (Theory and experiments are reconciled by reconsidering the hydrogen atom adsorption energetics with the help of van der Waals-inclusive density functional calculations that properly account for the basis set superposition error. It is shown that today van der Waals-density functional theory predicts a shallow physisorption well that nicely agrees with available experimental data and suggests that the hydrogen atom adsorption barrier in graphene is 180 meV high, within ˜5 meV accuracy.

  14. Startech Hydrogen Production Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Startech Engineering Department

    2007-11-27

    The assigned work scope includes the modification and utilization of the Plasma Converter System, Integration of a StarCell{trademark} Multistage Ceramic Membrane System (StarCell), and testing of the integrated systems towards DOE targets for gasification and membrane separation. Testing and evaluation was performed at the Startech Engineering and Demonstration Test Center in Bristol, CT. The Objectives of the program are as follows: (1) Characterize the performance of the integrated Plasma Converter and StarCell{trademark} Systems for hydrogen production and purification from abundant and inexpensive feedstocks; (2) Compare integrated hydrogen production performance to conventional technologies and DOE benchmarks; (3) Run pressure and temperature testing to baseline StarCell's performance; and (4) Determine the effect of process contaminants on the StarCell{trademark} system.

  15. Technical files. Hydrogen memento; Fiches techniques. Memento de l'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document is a compilation of 30 technical files about hydrogen and its related technologies. These files cover the following aspects: general considerations (world energy consumption growth, contribution of developing countries, atmospheric pollution and greenhouse effect, health impacts, actions implemented at the world scale, role of hydrogen); glossary and acronyms; units used and conversions; world energy situation (primary production, sectoral consumption, demand trends, environmental impact, situation of fossil fuel reserves); French energy situation (primary sources, energy independence ratio, electric power status, evolutions and trends of the French energy demand); fuel cells; basic data on hydrogen (thermodynamic properties and data); hydrogen production by water electrolysis, application to small capacity systems; thermochemical water dissociation; water photo-electrolysis; hydrogen pipeline networks in the world; mechanical energy production; hydrogen thermal engines; aeronautic applications; research laboratories; industrial actors of the hydrogen sector (companies, activities, geographical situation, financial structure, strategy, R and D, cooperations, projects etc..); hydrogen flammability and explosiveness; transport and storage safety; standards and regulations about hydrogen safety in France, in Europe and in the rest of the world; hydrogen programs in the world; the programs financed by the European Union; the German programs; the programs in Island, France and UK; the programs in North America; the Japanese programs; table of the main recent R and D projects per type of program; light vehicles with fuel cells; the Daimler-Chrysler program. (J.S.)

  16. Technical files. Hydrogen memento; Fiches techniques. Memento de l'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-07-01

    This document is a compilation of 30 technical files about hydrogen and its related technologies. These files cover the following aspects: general considerations (world energy consumption growth, contribution of developing countries, atmospheric pollution and greenhouse effect, health impacts, actions implemented at the world scale, role of hydrogen); glossary and acronyms; units used and conversions; world energy situation (primary production, sectoral consumption, demand trends, environmental impact, situation of fossil fuel reserves); French energy situation (primary sources, energy independence ratio, electric power status, evolutions and trends of the French energy demand); fuel cells; basic data on hydrogen (thermodynamic properties and data); hydrogen production by water electrolysis, application to small capacity systems; thermochemical water dissociation; water photo-electrolysis; hydrogen pipeline networks in the world; mechanical energy production; hydrogen thermal engines; aeronautic applications; research laboratories; industrial actors of the hydrogen sector (companies, activities, geographical situation, financial structure, strategy, R and D, cooperations, projects etc..); hydrogen flammability and explosiveness; transport and storage safety; standards and regulations about hydrogen safety in France, in Europe and in the rest of the world; hydrogen programs in the world; the programs financed by the European Union; the German programs; the programs in Island, France and UK; the programs in North America; the Japanese programs; table of the main recent R and D projects per type of program; light vehicles with fuel cells; the Daimler-Chrysler program. (J.S.)

  17. 77 FR 18243 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC); Notice of Open Meeting

    Science.gov (United States)

    2012-03-27

    ... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC); Notice of Open... open meeting. SUMMARY: This notice announces a meeting of the Hydrogen and Fuel Cell Technical Advisory... Committee: The Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) was established under Section 807...

  18. 78 FR 60866 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2013-10-02

    ... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Office of...: This notice announces an open meeting of the Hydrogen and Fuel Cell Technical Advisory Committee (HTAC... Committee: The Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) was established under section 807...

  19. Studies of ethylene hydrogenation and of adsorbed C/sub 2/H/sub 4/ and H/sub 2/ on chromia and lanthana catalysts

    Energy Technology Data Exchange (ETDEWEB)

    Khodakov, Y.S.; Makarov, P.A.; Delzer, G.; Minachev, K.M.

    1980-01-01

    Temperature-programed desorption of ethylene or hydrogen adsorbed at -78/sup 0/, -68/sup 0/, and +20/sup 0/C on chromic oxide, a 1:7 chromic oxide/alumina catalyst prepared by impregnation, alumina, and lanthanum oxide pretreated at 400/sup 0/-900/sup 0/C in vacuo showed that ethylene adsorbed on these oxides on three different sites from which it desorbed at -40/sup 0/ to +10/sup 0/C, at 50/sup 0/-100/sup 0/C, and at 350/sup 0/-400/sup 0/C; and that hydrogen adsorbed only on the latter two sites. One preadsorbed ethylene molecule was displaced at room temperature by 16 molecules of carbon monoxide, 79 molecules of carbon dioxide, or 135 molecules of water. Hydrogen was displaced at lower temperature. The nature of the surface sites and of the adsorbed species, and their reactivities are discussed.

  20. Bellona and hydrogen - the role of mediation in technical change

    International Nuclear Information System (INIS)

    Kristiansen, Beate

    2001-01-01

    The energy production and consumption is a major contributor to our environmental problems. The energy carrier hydrogen can be a part of the solution. In the thesis the Bellona Foundation's role in the process of technical change towards utilisation of hydrogen in Norway is investigated. Its role is analysed through the concept of mediation, which is based on seeing technical change as a social process. Mediators connect, or build bridges between, different actors, as well as between different types of knowledge. They establish new kinds of links and create new arenas of interaction for previously separated units. In addition, or through their work, they translate knowledge from one context or domain to another. They are also processing, interpreting and combining knowledge in new ways. Mediators bring together people with different competencies, and orchestrate their efforts often on a consensus basis. Bellona combines the different kinds of mediations, to influence the process of technical change at various levels and steps. They mediate mainly within the industry and between the industrial- and governmental domain. To some degree they also mediate between the experts and the public. But the direct contact with the public seems to be more or less absent in their hydrogen work. It seems like Bellona's mediator role fills an open space in the realm of technology policy making. Environmental oriented NGOs will perform or combine various mediating roles differently. To be able to make socially appropriate and sustainable technical change, probably other actors than the established traditional ones should be more involved. The possibilities for public participation should be strengthened, as well as the possibilities for mediation. (Author)

  1. Texas Hydrogen Education Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, David; Bullock, Dan

    2011-06-30

    , and hydrogen fueling) are effective for engaging target audiences, and (3) a clear path forward is needed for state and local agencies interested in project implementation (funding, financing, preliminary design, technical assistance, etc.).

  2. A new immobilized biomass technical adsorbent for uranium recovery from bioleach solutions in the mine

    International Nuclear Information System (INIS)

    Tsezos, Marios; Noh, S.H.

    1988-01-01

    A new type of metal adsorbent has been developed using inactive microbial biomass as the raw material. The adsorbent can be made to a desirable particle size. The particles have good mechanical strength and resistance to compression and consequently can be used in a packed bed resulting in a low pressure drop. The new biosorbents have been shown to maintain well the biosorptive properties of the immobilized biomass used for their production. We have tested successfully the new biosorbents for the recovery of uranium from actual bioleach solutions. (author)

  3. 76 FR 4645 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2011-01-26

    ... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Department...: This notice announces a meeting of the Hydrogen and Fuel Cell Technical Advisory Committee (HTAC). HTAC... Agenda: (Subject to change; updates will be posted on http://hydrogen.energy.gov and copies of the final...

  4. 76 FR 60478 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2011-09-29

    ... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Department...: The Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) was established under section 807 of... website at: http://hydrogen.energy.gov and copies of the final agenda will available the date of the...

  5. 78 FR 6086 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2013-01-29

    ... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Office of...). SUMMARY: This notice announces an open meeting (Webinar) of the Hydrogen and Fuel Cell Technical Advisory... Avenue, Washington, DC 20585. SUPPLEMENTARY INFORMATION: Purpose of the Committee: The Hydrogen and Fuel...

  6. 77 FR 2714 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2012-01-19

    ... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Department.... SUMMARY: This notice announces an open meeting of the Hydrogen and Fuel Cell Technical Advisory Committee... posted on http://hydrogen.energy.gov ). Public Comment (10 minutes) Discussion of HTAC's draft annual...

  7. 75 FR 59705 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2010-09-28

    ... DEPARTMENT OF ENERGY Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) AGENCY: Department...: The Hydrogen and Fuel Cell Technical Advisory Committee (HTAC) was established under section 807 of... Agenda Topics: (Subject to change; updates will be posted on the web at http://hydrogen.energy.gov and...

  8. Transition towards a hydrogen economy: infrastructures and technical change

    International Nuclear Information System (INIS)

    Bento, Nuno

    2010-01-01

    The double constraint of climate change and increasing scarcity of oil requires that we consider alternative energies for the medium term. This thesis focuses on the development of a hydrogen economy, which is conditional on the existence of an infrastructure for the distribution of the new fuel and the readiness of fuel cells. The main idea is that the state can play a central role in both infrastructure implementation and preparation of fuel cells technology. The thesis begins with a techno-economic analysis of the hydrogen-energy chain, which highlights the difficulty of setting up the infrastructure. The study of the development of electricity and gas networks in the past provides the empirical basis supporting the hypothesis that government can play an important role to consolidate the diffusion of socio-technical networks. In addition, private projects of stations may be justified by early-move benefits, although their financial viability depends on the demand for hydrogen which is in turn dependent on the performance of the fuel cell vehicle. The introduction of radical innovations, such as fuel cell, has been made more difficult by the domination of conventional technologies. This assertion is particularly true in the transport sector which was progressively locked into fossil fuels by a process of technological and institutional co-evolution driven by increasing returns of scale. Hence, fuel cells may primarily diffuse through the accumulation of niches where the innovation is closer to commercialization. These niches may be located in portable applications segment. Investments in research and demonstration are still necessary in order to reduce costs and increase performances of fuel cells. Using a simple model of multi-technological diffusion, we analyze the competition between the hydrogen fuel cell vehicle and the plug-in hybrid car for the automotive market. We show that an early entry of the latter may block the arrival of hydrogen in the market

  9. Specific equilibrium behavior of hydrogen isotopes adsorbed onto synthetic zeolite A-type governed by lithium cations

    International Nuclear Information System (INIS)

    Takashima, Shoji; Kotoh, Kenji

    2013-01-01

    Highlights: • Isotherms for H 2 and D 2 adsorbed onto SZ-LiA at 77.4 K are shown. • The adsorption isotherms exhibit specific deviation in the range lower than 10 Pa. • SZ-LiA indicates the power of several 100-times at 0.1 Pa, compared with SZ-NaA. • Experimental isotherms are described empirically by a dual-site Langmuir equation. • The isotope effect on adsorption isotherms appears in the Langmuir constants. -- Abstract: Since synthetic zeolites (SZs) are powerfully adsorptive for hydrogen isotopes at cryogenic temperatures such as liquefied nitrogen, adsorption processes using these have been considered applicable to such as recovery of tritium from the lithium blanket of DT fusion reactor system. Onto these zeolites the adsorptions isotherms for hydrogen isotopes onto SZ-NaA, SZ-CaA and SZ-NaX at 77.4 K were already clarified experimentally and analytically. These isotherms exhibit similar profiles of Langmuir type. In this work, adsorption isotherms were examined for H 2 and D 2 on SZ-LiA at 77.4 K. SZ-LiA was made from SZ-NaA by exchanging its sodium ions for lithium ones, provided by TOSOH Corp. The experimental results demonstrate the specific equilibrium behavior of hydrogen isotopes adsorbed on SZ-LiA, deviating from isothermal profiles on SZ-CaA and SZ-NaX. SZ-LiA show the isothermal profiles of adsorption for H 2 and D 2 similar to on the conventional zeolites in the range from around 1 kPa to the atmospheric pressure, but exhibit a plateau around 1 mol/kg between 0.1 Pa and 100 Pa, while other zeolites show linearly profiling isotherms. This deviation indicates the adsorptive power of SZ-LiA remarkably greater than that of the others

  10. Emission spectroscopy of hydrogen molecules in technical and divertor plasmas

    International Nuclear Information System (INIS)

    Fantz, U.

    2002-01-01

    The paper gives an overview of the diagnostics of hydrogen molecules in technical plasmas (MW and RF discharges) and in divertor plasmas of fusion experiments (ASDEX Upgrade / Tokamak at the Max-Planck-Institut fuer Plasmaphysik in Garching near Munich, Germany). The Fulcher transition in the visible spectral range was chosen for analysis since this is the most prominent band in the spectrum of molecular hydrogen. Examples for diagnostics of molecular densities will be given, and the problems arising in the interpretation of spectra will be discussed. In divertor plasmas the diagnostics of molecular.uxes will be introduced and the contribution of molecules to the plasma recombination will be discussed. Results for vibrational populations in the ground state and the correlation to the upper Fulcher state will be given, providing an electron temperature diagnostic. Finally, the in.uence of surfaces (high-grade steel and graphite) on vibrational populations and on re.ection coe.cients of atoms will be shown. Special attention is given on a comparison of the isotopes hydrogen and deuterium. (Abstract Copyright [2002], Wiley Periodicals, Inc.)

  11. Technical analysis of photovoltaic/wind systems with hydrogen storage

    Directory of Open Access Journals (Sweden)

    Bakić Vukman V.

    2012-01-01

    Full Text Available The technical analysis of a hybrid wind-photovoltaic energy system with hydrogen gas storage was studied. The market for the distributed power generation based on renewable energy is increasing, particularly for the standalone mini-grid applications. The main design components of PV/Wind hybrid system are the PV panels, the wind turbine and an alkaline electrolyzer with tank. The technical analysis is based on the transient system simulation program TRNSYS 16. The study is realized using the meteorological data for a Typical Metrological Year (TMY for region of Novi Sad, Belgrade cities and Kopaonik national park in Serbia. The purpose of the study is to design a realistic energy system that maximizes the use of renewable energy and minimizes the use of fossil fuels. The reduction in the CO2 emissions is also analyzed in the paper. [Acknowledgment. This paper is the result of the investigations carried out within the scientific project TR33036 supported by the Ministry of Science of the Republic of Serbia.

  12. 77 FR 65542 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2012-10-29

    ... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Hydrogen and Fuel Cell... Energy. ACTION: Notice of Open Meeting. SUMMARY: The Hydrogen and Fuel Cell Technical Advisory Committee... Agenda: (updates will be posted on the web at: http://hydrogen.energy.gov ). Public Comment DOE Program...

  13. 75 FR 2860 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2010-01-19

    ... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Hydrogen and Fuel Cell... Energy. ACTION: Notice of Open Meeting. SUMMARY: The Hydrogen and Fuel Cell Technical Advisory Committee... change; updates will be posted on http://hydrogen.energy.gov and copies of the final agenda will...

  14. New Material Overcomes a Long-Standing Challenge for Efficient, Onboard Storage of Hydrogen using Adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Fuel Cell Technologies Office

    2018-02-28

    The quest to develop a low cost material that efficiently stores hydrogen onboard fuel cell electric vehicles at low pressures and near room temperature has been pursued by U.S. Department of Energy since the early 2000s. This success story describes a recent early stage scientific breakthrough by researchers at Lawrence Berkeley National Laboratory that could open the door to achieving a material that offers a 300+ mile driving range with 5 minute refuels, while still only emitting water vapor at the tail pipe.

  15. Attachment of polybutadienes to hydrogen-terminated silicon and post-derivatization of the adsorbed species.

    Science.gov (United States)

    Wickard, Todd D; Nelsen, Emily; Madaan, Nitesh; ten Brummelhuis, Niels; Diehl, Christina; Schlaad, Helmut; Davis, Robert C; Linford, Matthew R

    2010-02-02

    We report the first attachment of polymers with pendant vinyl groups to hydrogen-terminated silicon(111) (Si(111)-H); 1,2-polybutadiene (M(w) = 3200-3500 g/mol) was attached to Si(111)-H under mild conditions at room temperature with visible light. We also report the partial functionalization, in solution, of 1,2-polybutadiene with various thiols using thiol-ene chemistry and the subsequent attachments of these compounds to Si(111)-H. The partially functionalized or unfunctionalized polybutadienes allow further functionalization at the surface through their unreacted carbon-carbon double bonds. We present this as a useful strategy for silicon surface modification. Surfaces were characterized with contact angle goniometry, spectroscopic ellipsometry, X-ray photoelectron spectroscopy (XPS), time-of-flight secondary ion mass spectrometry (ToF-SIMS), and atomic force microscopy (AFM).

  16. FTIR spectroscopy and thermodynamics of hydrogen adsorbed in a cross-linked polymer.

    Science.gov (United States)

    Spoto, Giuseppe; Vitillo, Jenny G; Cocina, Donato; Damin, Alessandro; Bonino, Francesca; Zecchina, Adriano

    2007-09-28

    The adsorption of H(2) in a cross-linked poly(styrene-co-divinylbenzene) (St-DVB) microporous polymer (BET surface area 920 m(2) g(-1)) is studied by volumetric and gravimetric methods, FTIR spectroscopy at variable temperature (300-14 K) and ab initio calculations. At 77 K the polymer reversibly stores up to 1.3 mass% H(2) at a pressure of 1 bar and 1.8 mass% at 10 bar. The adsorption process involves the specific interaction of H(2) with the structural phenyl rings through weak dispersive forces. The interacting molecules become IR active and give rise to vibrational and rotational-vibrational manifestations which are affected by the temperature, the contact time and the H(2) equilibrium pressure. The spectra of the H(2)/St-DVB system reported here represent the first IR evidence of the adsorption of hydrogen on unsaturated molecules. The adsorption enthalpy is evaluated by the VTIR (variable temperature IR spectroscopy) method (C. Otero Areán et al., Phys. Chem. Chem. Phys., 2007, DOI: 10.1039/b615535a) and compared with the results of ab initio calculations for the H(2)/benzene interaction and with literature data.

  17. The hydrogen resource. Productive, technical and economic analysis

    International Nuclear Information System (INIS)

    De Fronzo, G.

    2000-01-01

    Diffusion of hydrogen as an energetic vector meets with a lot of obstacles that don't depend on available raw material, but on hydrogen combination with other elements. It is necessary, therefore, to separate hydrogen picking out the available different technologies to have different pure hydrogen of variable quantities. Besides, its diffusion as fuel is limited because of the great production cost compared to fuels sprung from petroleum. Hydrogen used on a large scale could have advantages on the environment and occupation, but there are economic and politic obstacles to limit its diffusion. Future of economic system, based on hydrogen as the main energetic vector, will depend on the programme that national and international qualified governing bodies will be able to do [it

  18. H2 at Scale: Benefitting our Future Energy System - Update for the Hydrogen Technical Advisory Committee

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, Mark

    2016-12-06

    Hydrogen is a flexible, clean energy carrying intermediate that enables aggressive market penetration of renewables while deeply decarbonizing our energy system. H2 at Scale is a concept that supports the electricity grid by utilizing energy without other demands at any given time and also supports transportation and industry by providing low-priced hydrogen to them. This presentation is an update to the Hydrogen Technical Advisory Committee (HTAC).

  19. Technical project of complex fast cycle heat treatment of hydrogenous coal preparation

    OpenAIRE

    Moiseev, V. A.; Andrienko, V. G.; Pileckij, V. G.; Urvancev, A. I.; Gvozdyakov, Dmitry Vasilievich; Gubin, Vladimir Evgenievich; Matveev, Aleksandr Sergeevich; Savostiyanova, Ludmila Viktorovna

    2015-01-01

    Problems of heat-treated milled hydrogenous coal preparation site creation in leading fast cycle heat treatment complex were considered. Conditions for effective use of electrostatic methods of heat-treated milled hydrogenous coal preparation were set. Technical project of heat treatment of milled hydrogenous coal preparation site was developed including coupling of working equipment complex on fast heat treatment and experimental samples of equipment being designed for manufacturing. It was ...

  20. H2@Scale: Technical and Economic Potential of Hydrogen as an Energy Intermediate

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, Mark F [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Jadun, Paige [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Pivovar, Bryan S [National Renewable Energy Laboratory (NREL), Golden, CO (United States)

    2017-11-09

    The H2@Scale concept is focused on developing hydrogen as an energy carrier and using hydrogen's properties to improve the national energy system. Specifically hydrogen has the abilities to (1) supply a clean energy source for industry and transportation and (2) increase the profitability of variable renewable electricity generators such as wind turbines and solar photovoltaic (PV) farms by providing value for otherwise potentially-curtailed electricity. Thus the concept also has the potential to reduce oil dependency by providing a low-carbon fuel for fuel cell electric vehicles (FCEVs), reduce emissions of carbon dioxide and pollutants such as NOx, and support domestic energy production, manufacturing, and U.S. economic competitiveness. The analysis reported here focuses on the potential market size and value proposition for the H2@Scale concept. It involves three analysis phases: 1. Initial phase estimating the technical potential for hydrogen markets and the resources required to meet them; 2. National-scale analysis of the economic potential for hydrogen and the interactions between willingness to pay by hydrogen users and the cost to produce hydrogen from various sources; and 3. In-depth analysis of spatial and economic issues impacting hydrogen production and utilization and the markets. Preliminary analysis of the technical potential indicates that the technical potential for hydrogen use is approximately 60 million metric tons (MMT) annually for light duty FCEVs, heavy duty vehicles, ammonia production, oil refining, biofuel hydrotreating, metals refining, and injection into the natural gas system. The technical potential of utility-scale PV and wind generation independently are much greater than that necessary to produce 60 MMT / year hydrogen. Uranium, natural gas, and coal reserves are each sufficient to produce 60 MMT / year hydrogen in addition to their current uses for decades to centuries. National estimates of the economic potential of

  1. Defining the hydrogen bond: An account (IUPAC Technical Report)

    Czech Academy of Sciences Publication Activity Database

    Arunan, E.; Desiraju, G. R.; Klein, R. A.; Sadlej, J.; Scheiner, S.; Alkorta, I.; Clary, D. C.; Crabtree, R. H.; Dannenberg, J. J.; Hobza, Pavel; Kjaergaard, H. G.; Legon, A. C.; Mennucci, B.; Nesbitt, D. J.

    2011-01-01

    Roč. 83, č. 8 (2011), s. 1619-1636 ISSN 0033-4545 Institutional research plan: CEZ:AV0Z40550506 Keywords : bonding * electrostatic interactions * hydrogen bonding * molecular interactions Subject RIV: CF - Physical ; Theoretical Chemistry Impact factor: 2.789, year: 2011

  2. Hydrogen as a fuel for fuel cell vehicles: A technical and economic comparison

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.; Steinbugler, M.; Kreutz, T. [Princeton Univ., NJ (United States). Center for Energy and Environmental Studies

    1997-12-31

    All fuel cells currently being developed for near term use in vehicles require hydrogen as a fuel. Hydrogen can be stored directly or produced onboard the vehicle by reforming methanol, ethanol or hydrocarbon fuels derived from crude oil (e.g., Diesel, gasoline or middle distillates). The vehicle design is simpler with direct hydrogen storage, but requires developing a more complex refueling infrastructure. In this paper, the authors compare three leading options for fuel storage onboard fuel cell vehicles: compressed gas hydrogen storage; onboard steam reforming of methanol; onboard partial oxidation (POX) of hydrocarbon fuels derived from crude oil. Equilibrium, kinetic and heat integrated system (ASPEN) models have been developed to estimate the performance of onboard steam reforming and POX fuel processors. These results have been incorporated into a fuel cell vehicle model, allowing us to compare the vehicle performance, fuel economy, weight, and cost for various fuel storage choices and driving cycles. A range of technical and economic parameters were considered. The infrastructure requirements are also compared for gaseous hydrogen, methanol and hydrocarbon fuels from crude oil, including the added costs of fuel production, storage, distribution and refueling stations. Considering both vehicle and infrastructure issues, the authors compare hydrogen to other fuel cell vehicle fuels. Technical and economic goals for fuel cell vehicle and hydrogen technologies are discussed. Potential roles for hydrogen in the commercialization of fuel cell vehicles are sketched.

  3. Technical Assessment of Cryo-Compressed Hydrogen Storage Tank Systems for Automotive Applications

    Energy Technology Data Exchange (ETDEWEB)

    Ahluwalia, Rajesh [Argonne National Lab. (ANL), Argonne, IL (United States); Hua, T. Q. [Argonne National Lab. (ANL), Argonne, IL (United States); Peng, J. -K. [Argonne National Lab. (ANL), Argonne, IL (United States); Lasher, S. [TIAX LLC, Lexington, MA (United States); McKenney, Kurtis [TIAX LLC, Lexington, MA (United States); Sinha, J. [TIAX LLC, Lexington, MA (United States)

    2009-12-01

    Technical report describing DOE's second assessment report on a third generation (Gen3) system capable of storing hydrogen at cryogenic temperatures within a pressure vessel on-board a vehicle. The report includes an overview of technical progress to date, including the potential to meet DOE onboard storage targets, as well as independent reviews of system cost and energy analyses of the technology paired with delivery costs.

  4. High-capacity hydrogen storage in Li-adsorbed g-C{sub 3}N{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Jianfeng; Huang, Chengxi; Wu, Haiping, E-mail: mrhpwu@njust.edu.cn; Kan, Erjun, E-mail: ekan@njust.edu.cn

    2016-09-01

    Since hydrogen is a kind of potential source of efficient and pollution-free energy, it has attracted great research interests in recent years. However, the lack of safe and efficient hydrogen storage materials has blocked the rapid development of hydrogen energy. Here, we explored the possibility of Li-decorated g-C{sub 3}N{sub 4} as a kind of potential hydrogen storage materials based on first-principles calculations. Our results demonstrated that the adsorption energy of Li atoms on g-C{sub 3}N{sub 4} is much larger than the cohesive energy of bulk Li. Importantly, we find that the binding energy of each H{sub 2} molecule is about 0.29 eV, which is quite suitable for hydrogen storage. Furthermore, the estimated hydrogen storage capacity is around 9.2 wt %, which beyonds the goal of DOE. Thus, we predicted that Li-decorated g-C{sub 3}N{sub 4} may act as the potential hydrogen storage materials. - Highlights: • We explored the possibility of Li-decorated g-C{sub 3}N{sub 4} as a kind of potential hydrogen storage material. • We demonstrated the binding energy of each H{sub 2} molecule is 0.29 eV, which is quite suitable for hydrogen storage materials. • The hydrogen storage capacity is estimated around 9.2 wt %.

  5. Steam reforming of technical bioethanol for hydrogen production

    DEFF Research Database (Denmark)

    Rass-Hansen, Jeppe; Johansson, Roger; Møller, Martin Hulbek

    2008-01-01

    Essentially all work on ethanol steam reforming so far has been carried out using simulated bioethanol feedstocks, which means pure ethanol mixed with water. However, technical bioethanol consists of a lot of different components including sugars, which cannot be easily vaporized and steam reformed....... For ethanol steam reforming to be of practical interest, it is important to avoid the energy-intensive purification steps to fuel grade ethanol. Therefore, it is imperative to analyze how technical bioethanol, with the relevant impurities, reacts during the steam reforming process. We show how three different...... bioethanol will result in a faster catalyst deactivation than what is observed when using pure ethanol-water mixtures because of contaminants remaining in the feed. However, the initial activity of the catalysts are not affected by this, hence it is important to not only focus on catalyst activity but rather...

  6. Hydrogen Energy Storage: Grid and Transportation Services (Technical Report)

    Energy Technology Data Exchange (ETDEWEB)

    Melaina, M. [National Renewable Energy Lab. (NREL), Golden, CO (United States); Eichman, J. [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2015-02-01

    Proceedings of an expert workshop convened by the U.S. Department of Energy and Industry Canada, and hosted by the National Renewable Energy Laboratory and the California Air Resources Board, May 14-15, 2014, in Sacramento, California, to address the topic of hydrogen energy storage (HES). HES systems provide multiple opportunities to increase the resilience and improve the economics of energy sup supply systems underlying the electric grid, gas pipeline systems, and transportation fuels. This is especially the case when considering particular social goals and market drivers, such as reducing carbon emissions, increasing reliability of supply, and reducing consumption of conventional petroleum fuels. This report compiles feedback collected during the workshop, which focused on policy and regulatory issues related to HES systems. Report sections include an introduction to HES pathways, market demand, and the "smart gas" concept; an overview of the workshop structure; and summary results from panel presentations and breakout groups.

  7. Final Technical Report for GO17004 Regulatory Logic: Codes and Standards for the Hydrogen Economy

    Energy Technology Data Exchange (ETDEWEB)

    Nakarado, Gary L. [Regulatory Logic LLC, Golden, CO (United States)

    2017-02-22

    The objectives of this project are to: develop a robust supporting research and development program to provide critical hydrogen behavior data and a detailed understanding of hydrogen combustion and safety across a range of scenarios, needed to establish setback distances in building codes and minimize the overall data gaps in code development; support and facilitate the completion of technical specifications by the International Organization for Standardization (ISO) for gaseous hydrogen refueling (TS 20012) and standards for on-board liquid (ISO 13985) and gaseous or gaseous blend (ISO 15869) hydrogen storage by 2007; support and facilitate the effort, led by the NFPA, to complete the draft Hydrogen Technologies Code (NFPA 2) by 2008; with experimental data and input from Technology Validation Program element activities, support and facilitate the completion of standards for bulk hydrogen storage (e.g., NFPA 55) by 2008; facilitate the adoption of the most recently available model codes (e.g., from the International Code Council [ICC]) in key regions; complete preliminary research and development on hydrogen release scenarios to support the establishment of setback distances in building codes and provide a sound basis for model code development and adoption; support and facilitate the development of Global Technical Regulations (GTRs) by 2010 for hydrogen vehicle systems under the United Nations Economic Commission for Europe, World Forum for Harmonization of Vehicle Regulations and Working Party on Pollution and Energy Program (ECE-WP29/GRPE); and to Support and facilitate the completion by 2012 of necessary codes and standards needed for the early commercialization and market entry of hydrogen energy technologies.

  8. Hydrogen Station Compression, Storage, and Dispensing Technical Status and Costs: Systems Integration

    Energy Technology Data Exchange (ETDEWEB)

    Parks, G.; Boyd, R.; Cornish, J.; Remick, R.

    2014-05-01

    At the request of the U.S. Department of Energy Fuel Cell Technologies Office (FCTO), the National Renewable Energy Laboratory commissioned an independent review of hydrogen compression, storage, and dispensing (CSD) for pipeline delivery of hydrogen and forecourt hydrogen production. The panel was asked to address the (1) cost calculation methodology, (2) current cost/technical status, (3) feasibility of achieving the FCTO's 2020 CSD levelized cost targets, and to (4) suggest research areas that will help the FCTO reach its targets. As the panel neared the completion of these tasks, it was also asked to evaluate CSD costs for the delivery of hydrogen by high-pressure tube trailer. This report details these findings.

  9. Technical Analysis of the Hydrogen Energy Station Concept, Phase I and Phase II

    Energy Technology Data Exchange (ETDEWEB)

    TIAX, LLC

    2005-05-04

    patterns would be most viable for an energy station, TIAX developed several criteria for selecting a representative set of technology configurations. TIAX applied these criteria to all possible technology configurations to determine an optimized set for further analysis, as shown in Table ES-1. This analysis also considered potential energy station operational scenarios and their impact upon hydrogen and power production. For example, an energy station with a 50-kWe reformer could generate enough hydrogen to serve up to 12 vehicles/day (at 5 kg/fill) or generate up to 1,200 kWh/day, as shown in Figure ES-1. Buildings that would be well suited for an energy station would utilize both the thermal and electrical output of the station. Optimizing the generation and utilization of thermal energy, hydrogen, and electricity requires a detailed look at the energy transfer within the energy station and the transfer between the station and nearby facilities. TIAX selected the Baseline configuration given in Table ES-1 for an initial analysis of the energy and mass transfer expected from an operating energy station. Phase II The purpose of this technical analysis was to analyze the development of a hydrogen-dispensing infrastructure for transportation applications through the installation of a 50-75 kW stationary fuel cell-based energy station at federal building sites. The various scenarios, costs, designs and impacts of such a station were quantified for a hypothetical cost-shared program that utilizes a natural gas reformer to provide hydrogen fuel for both the stack(s) and a limited number of fuel cell powered vehicles, with the possibility of using cogeneration to support the building heat load.

  10. Achieving Hydrogen Storage Goals through High-Strength Fiber Glass - Final Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Li, Hong [PPG Industries, Inc., Cheswick, PA (United States); Johnson, Kenneth I. [PPG Industries, Inc., Cheswick, PA (United States); Newhouse, Norman L. [PPG Industries, Inc., Cheswick, PA (United States)

    2017-06-05

    Led by PPG and partnered with Hexagon Lincoln and Pacific Northwest National Laboratory (PNNL), the team recently carried out a project “Achieving Hydrogen Storage Goals through High-Strength Fiber Glass”. The project was funded by DOE’s Fuel Cell Technologies office within the Office of Energy Efficiency and Renewable Energy, starting on September 1, 2014 as a two-year project to assess technical and commercial feasibilities of manufacturing low-cost, high-strength glass fibers to replace T700 carbon fibers with a goal of reducing the composite total cost by 50% of the existing, commercial 700 bar hydrogen storage tanks used in personal vehicles.

  11. A technical and environmental comparison between hydrogen and some fossil fuels

    International Nuclear Information System (INIS)

    Nicoletti, Giovanni; Arcuri, Natale; Nicoletti, Gerardo; Bruno, Roberto

    2015-01-01

    Highlights: • Hydrogen as new non-conventional energy system. • Technical and environmental comparison between different type of fuels. • Combustion products analysis. • Technical and environmental quality indexes for investigated fuels. • Proposal of a suitable new energy scenario supplied by hydrogen. - Abstract: The exploitation of some fossil fuels such as oil, intended as gasoline or diesel fuel, natural gas and coal, currently satisfy the majority of the growing world energy demand, but they are destined to run out relatively quickly. Beyond this point, their combustion products are the main cause of some global problems such as the greenhouse effect, the hole in the ozone layer, acid rains and generalized environment pollution, so their impact is extremely harmful. Therefore, it is clear that a solution to the energy problem can be obtained only through the use of renewable sources and by means of the exploitation of new low-polluting fuels. In this scenario an important role might be played by hydrogen, which is able to define a new energy system that is more sustainable and cleaner than current systems. For the comparison of the different fuels investigated in this paper, a methodology, which defines appropriate technical and environmental quality indexes, has been developed. These indexes are connected to the pollution produced by combustion reactions and to their intrinsic characteristics of flammability and expansiveness linked to the use of the considered fuels. An appropriate combination of these indexes, in the specific sector of utilization, allows to evaluate a global environmental index for the investigated fuels, highlighting that hydrogen reaches the highest score. In the final part of the paper, a new hydrogen energy economy that would lead to solving the serious environmental problems that damages all the ecosystems of the planet earth, is presented

  12. Materials Down Select Decisions Made Within the Department of Energy Hydrogen Sorption Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Simpson, Lin [National Renewable Energy Lab. (NREL), Golden, CO (United States)

    2009-11-30

    Technical report describing DOE's Hydrogen Sorption Center of Excellence investigation into various adsorbent and chemisorption materials and progress towards meeting DOE's hydrogen storage targets. The report presents a review of the material status as related to DOE hydrogen storage targets and explains the basis for the down select decisions.

  13. Interim technical evaluation report of testing procedures for activated carbon adsorbers in ventilation filter assemblies in nuclear power plants

    International Nuclear Information System (INIS)

    Sill, C.W.; Scarpellino, C.D.; Tkachyk, J.W.; Grey, A.E.; Frank, C.W.

    1985-05-01

    Laboratory analysis of activated carbon is required by nuclear power plant technical specifications for use in Engineered Safety Feature (ESF) ventilation systems to determine the capability of those systems to remove radioiodines from air during normal operation and following a design basis accident (DBA). The lask of agreement of laboratory results from a recent round robin raised concerns regarding the adequacy of the analyses, using the ASTM D3803-79 standard, to assure compliance with plant technical specifications. EG and G Idaho was contracted by the NRC to conduct a program to provide the bases for resolving these concerns. This EG and G report serves as an interim Technical Evaluation Report (TER) of the program and presents reviews of the ASTM D3803-79 standard and the commercial testing laboratories. Results of EG and G laboratory studies and the NRC/EG and G Interlaboratory Comparison are presented with conclusions and recommendations concerning changes required to improve the standard and its application. Possible revisions to plant technical specifications required to reflect the true capability of activated carbon to remove radioiodines are also presented

  14. Theory of ortho-para conversion in hydrogen adsorbed on metal and paramagnetic surfaces at low temperatures

    International Nuclear Information System (INIS)

    Yucel, S.

    1989-01-01

    In order to explain the experimental results on Cu(100), Ag(111), Ag thin films, graphite, and H 2 bubbles in Cu, the ortho-para conversion rates of H 2 and D 2 adsorbed on metal and paramagnetic surfaces at low temperatures have been considered. The conversion rates due to magnetic dipole-dipole, Fermi contact, and spin-orbit interaction between the conduction electrons, and nuclear spins of H 2 (D 2 ) are calculated to elucidate the role of the metal surface. Although the rates on clean metal surfaces are found to be too slow to account for the observed rates on Ag, they may explain the catalytic conversion on H 2 bubble surfaces at 1.3 K. Additionally, effects of impurities and defects on the surface are investigated by calculating the conversion rate in two-dimensional solid D 2 (H 2 ) by emission of one (two) phonon(s). Fast conversion rates observed on Ag and graphite surfaces as well as on the surfaces of H 2 bubbles may be accounted for by paramagnetic impurities or defects. On Grafoil, both in (√3 x √3)R30 0 commensurate and incommensurate solid phase, a temperature-independent conversion rate is predicted if the mobility of the molecules is high enough to prevent concentration gradients

  15. Quantum chemical investigation on the role of Li adsorbed on anatase (101) surface nano-materials on the storage of molecular hydrogen.

    Science.gov (United States)

    Srinivasadesikan, V; Raghunath, P; Lin, M C

    2015-06-01

    Lithiation of TiO2 has been shown to enhance the storage of hydrogen up to 5.6 wt% (Hu et al. J Am Chem Soc 128:11740-11741, 2006). The mechanism for the process is still unknown. In this work we have carried out a study on the adsorption and diffusion of Li atoms on the surface and migration into subsurface layers of anatase (101) by periodic density functional theory calculations implementing on-site Coulomb interactions (DFT+U). The model consists of 24 [TiO2] units with 11.097 × 7.655 Å(2) surface area. Adsorption energies have been calculated for different Li atoms (1-14) on the surface. A maximum of 13 Li atoms can be accommodated on the surface at two bridged O, Ti-O, and Ti atom adsorption sites, with 83 kcal mol(-1) adsorption energy for a single Li atom adsorbed between two bridged O atoms from where it can migrate into the subsurface layer with 27 kcal mol(-1) energy barrier. The predicted adsorption energies for H2 on the lithiated TiO2 (101) surface with 1-10 Li atoms revealed that the highest adsorption energies occurred on 1-Li, 5-Li, and 9-Li surfaces with 3.5, 4.4, and 7.6 kcal mol(-1), respectively. The values decrease rapidly with additional H2 co-adsorbed on the lithiated surfaces; the maximum H2 adsorption on the 9Li-TiO2(a) surface was estimated to be only 0.32 wt% under 100 atm H2 pressure at 77 K. The result of Bader charge analysis indicated that the reduction of Ti occurred depending on the Li atoms covered on the TiO2 surface.

  16. Hydrogen production by supercritical water gasification of biomass. Phase 1 -- Technical and business feasibility study, technical progress report

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    1997-12-01

    The nine-month Phase 1 feasibility study was directed toward the application of supercritical water gasification (SCWG) for the economical production and end use of hydrogen from renewable energy sources such as sewage sludge, pulp waste, agricultural wastes, and ultimately the combustible portion of municipal solid waste. Unique in comparison to other gasifier systems, the properties of supercritical water (SCW) are ideal for processing biowastes with high moisture content or contain toxic or hazardous contaminants. During Phase I, an end-to-end SCWG system was evaluated. A range of process options was initially considered for each of the key subsystems. This was followed by tests of sewage sludge feed preparation, pumping and gasification in the SCW pilot plant facility. Based on the initial process review and successful pilot-scale testing, engineering evaluations were performed that defined a baseline system for the production, storage and end use of hydrogen. The results compare favorably with alternative biomass gasifiers currently being developed. The results were then discussed with regional wastewater treatment facility operators to gain their perspective on the proposed commercial SCWG systems and to help define the potential market. Finally, the technical and business plans were developed based on perceived market needs and the projected capital and operating costs of SCWG units. The result is a three-year plan for further development, culminating in a follow-on demonstration test of a 5 MT/day system at a local wastewater treatment plant.

  17. Dramatic effect of pore size reduction on the dynamics of hydrogen adsorbed in metal–organic materials

    KAUST Repository

    Nugent, Patrick

    2014-07-21

    The effects of pore size reduction on the dynamics of hydrogen sorption in metal-organic materials (MOMs) were elucidated by studying SIFSIX-2-Cu and its doubly interpenetrated polymorph SIFSIX-2-Cu-i by means of sorption, inelastic neutron scattering (INS), and computational modeling. SIFSIX-2-Cu-i exhibits much smaller pore sizes, which possess high H2 sorption affinity at low loadings. Experimental H2 sorption measurements revealed that the isosteric heat of adsorption (Qst) for H2 in SIFSIX-2-Cu-i is nearly two times higher than that for SIFSIX-2-Cu (8.6 vs. 4.6 kJ mol-1). The INS spectrum for H2 in SIFSIX-2-Cu-i is rather unique for a porous material, as only one broad peak appears at low energies near 6 meV, which simply increases in intensity with loading until the pores are filled. The value for this rotational transition is lower than that in most neutral metal-organic frameworks (MOFs), including those with open Cu sites (8-9 meV), which is indicative of a higher barrier to rotation and stronger interaction in the channels of SIFSIX-2-Cu-i than the open Cu sites in MOFs. Simulations of H2 sorption in SIFSIX-2-Cu-i revealed two hydrogen sorption sites in the MOM: direct interaction with the equatorial fluorine atom (site 1) and between two equatorial fluorine atoms on opposite walls (site 2). The calculated rotational energy levels and rotational barriers for the two sites in SIFSIX-2-Cu-i are in good agreement with INS data. Furthermore, the rotational barriers and binding energies for site 2 are slightly higher than that for site 1, which is consistent with INS results. The lowest calculated transition for the primary site in SIFSIX-2-Cu is also in good agreement with INS data. In addition, this transition in the non-interpenetrating material is higher than any of the sites in SIFSIX-2-Cu-i, which indicates a significantly weaker interaction with the host as a result of the larger pore size. This journal is © the Partner Organisations 2014.

  18. Adsorbed Carbon Formation and Carbon Hydrogenation for CO_2 Methanation on the Ni(111) Surface: ASED-MO Study

    International Nuclear Information System (INIS)

    Choe, Sang Joon; Kang, Hae Jin; Kim, Su Jin; Park, Sung Bae; Park, Dong Ho; Huh, Do Sung

    2005-01-01

    Using the ASED-MO (Atom Superposition and Electron Delocalization-Molecular Orbital) theory, we investigated carbon formation and carbon hydrogenation for CO_2 methanation on the Ni (111) surface. For carbon formation mechanism, we calculated the following activation energies, 1.27 eV for CO_2 dissociation, 2.97 eV for the CO, 1.93 eV for 2CO dissociation, respectively. For carbon methanation mechanism, we also calculated the following activation energies, 0.72 eV for methylidyne, 0.52 eV for methylene and 0.50 eV for methane, respectively. We found that the calculated activation energy of CO dissociation is higher than that of 2CO dissociation on the clean surface and base on these results that the CO dissociation step are the ratedetermining of the process. The C-H bond lengths of CH_4 the intermediate complex are 1.21 A, 1.31 A for the C···H_(_1_), and 2.82 A for the height, with angles of 105 .deg. for H_(_1_)CH and 98 .deg. for H_(_1_)CH_(_1_)

  19. Technical Analysis of Projects Being Funded by the DOE Hydrogen Program

    Energy Technology Data Exchange (ETDEWEB)

    Edward G. Skolnik

    2006-02-10

    In July 2000, Energetics began a project in which we performed site-visit based technical analyses or evaluations on hydrogen R&D projects for the purpose of providing in-depth information on the status and accomplishments of these projects to the public, and especially to hydrogen stakeholders. Over a three year period, 32 site-visit analyses were performed. In addition two concepts gleaned from the site visits became subjects of in depth techno-economic analyses. Finally, Energetics produced a compilation document that contains each site-visit analysis that we have performed, starting in 1996 on other contracts through the end of Year One of the current project (July 2001). This included 21 projects evaluated on previous contracts, and 10 additional ones from Year One. Reports on projects visited in Years One and Two were included in their respective Annual Reports. The Year Two Report also includes the two In-depth Analyses and the Compilation document. Reports in Year three began an attempt to perform reviews more geared to hydrogen safety. This Final Report contains a summary of the overall project, all of the 32 site-visit analyses and the two In-depth Analyses.

  20. The Use of Adsorbent Materials of Improving the Characteristics of Polluted Soils, Part 1 Phytoremediation of Soils Polluted with Oil Products, Cultivated with Technical Plants

    Directory of Open Access Journals (Sweden)

    Smaranda Masu

    2015-10-01

    Full Text Available In this study are presented in pot experimental variants regarding alternatives to improve the characteristics of soils polluted with 74.12 ± 3.50 g·kg-1 D.M. total petroleum hydrocarbon (TPH in order to apply the phytoremediation process using technical plants from the common flax (Linum usitatissimum. The harmful effects of TPH polluted soils to plants was reduced by using fly ash from thermal plant as temporary adsorbent of non-polar pollutants, petroleum products. The increase of water retention capacity of the soil was achieved by treatments with indigenous volcanic tuff. The lack of nutrients, based on N and P in soils contaminated with TPH rich in C compounds are completed using sewage sludge anaerobically stabilized. The use of appropriate amounts of fly ash and fertilizer agents in the presence of volcanic tuff caused the formation of strong networks of roots and rich harvests of plants, stems and seeds from the treated soil. The TPH reduction efficiency of TPH polluted soils treated with fly ash (TPH soil: fly ash ratio 12:1 wt. / wt. and anaerobically stabilized sewage sludge respectively indigenous volcanic tuff during one vegetative cycle of crops was in the range of 56.2 - 63.25 %.

  1. Technical and economic evaluation of hydrogen storage systems based on light metal hydrides

    Energy Technology Data Exchange (ETDEWEB)

    Jepsen, Julian

    2014-07-01

    Novel developments regarding materials for solid-state hydrogen storage show promising prospects. These complex hydrides exhibit high mass-related storage capacities and thus great technical potential to store hydrogen in an efficient and safe way. However, a comprehensive evaluation of economic competitiveness is still lacking, especially in the case of the LiBH4 / MgH2 storage material. In this study, an assessment with respect to the economic feasibility of implementing complex hydrides as hydrogen storage materials is presented. The cost structure of hydrogen storage systems based on NaAlH4 and LiBH4 / MgH2 is discussed and compared with the conventional high pressure (700 bar) and liquid storage systems. Furthermore, the properties of LiBH4 / MgH2, so-called Li-RHC (Reactive Hydride Composite), are scientifically compared and evaluated on the lab and pilot plant scale. To enhance the reaction rate, the addition of TiCl3 is investigated and high energy ball milling is evaluated as processing technique. The effect of the additive in combination with the processing technique is described in detail. Finally, an optimum set of processing parameters and additive content are identified and can be applied for scaled-up production of the material based on simple models considering energy input during processing. Furthermore, thermodynamic, heat transfer and kinetic properties are experimentally determined by different techniques and analysed as a basis for modelling and designing scaled-up storage systems. The results are analysed and discussed with respect to the reaction mechanisms and reversibility of the system. Heat transfer properties are assessed with respect to the scale-up for larger hydrogen storage systems. Further improvements of the heat transfer were achieved by compacting the material. In this regard, the influence of the compaction pressure on the apparent density, thermal conductivity and sorption behaviour, was investigated in detail. Finally, scaled

  2. Solar powered hydrogen generating facility and hydrogen powered vehicle fleet. Final technical report, August 11, 1994--January 6, 1997

    Energy Technology Data Exchange (ETDEWEB)

    Provenzano, J.J.

    1997-04-01

    This final report describes activities carried out in support of a demonstration of a hydrogen powered vehicle fleet and construction of a solar powered hydrogen generation system. The hydrogen generation system was permitted for construction, constructed, and permitted for operation. It is not connected to the utility grid, either for electrolytic generation of hydrogen or for compression of the gas. Operation results from ideal and cloudy days are presented. The report also describes the achievement of licensing permits for their hydrogen powered trucks in California, safety assessments of the trucks, performance data, and information on emissions measurements which demonstrate performance better than the Ultra-Low Emission Vehicle levels.

  3. Final Technical Report: Hawaii Hydrogen Center for Development and Deployment of Distributed Energy Systems

    Energy Technology Data Exchange (ETDEWEB)

    Rocheleau, Richard E.

    2008-09-30

    -efficiency CIGS and a-Si:H with operating features compatible with high-efficiency photoelectrochemical (PEC) water-splitting. The objective of one activity under the hydrogen production from biomass task was to conduct parametric testing of the Pearson gasifier and to determine the effects of gasifier operating conditions on the gas yields and quality. The hydrogen yield from this gasifier was evaluated in a parametric test series over a range of residence times from 0.8 to 2.2 seconds. H2 concentrations as high as 55% (volume) were measured in the product gas at the longer residence times and this corresponds to a hydrogen yield of 90 kg per tonne of bagasse without gas upgrading. The objective of another activity was to develop hot gas clean-up capabilities for the HNEI gasifier test facility to support hydrogen-from-biomass research. The product gas stream at the outlet of the hot gas filter was characterized for concentrations of permanent gas species and contaminants. Biomass feedstock processing activity included a preliminary investigation into methods for processing sugar cane trash at the Puunene Sugar Factory on the island of Maui, Hawaii. The objective of the investigation was to explore treatment methods that would enable the successful use of cane trash as fuel for the production of hydrogen via gasification. Analyses were completed for the technical and economic feasibility of producing biofuel from photosynthetic marine microbes on a commercial scale. Results included estimates for total costs, energy efficiency, and return on investment. The biohydrogen team undertook a comprehensive review of the field and came to what is considered a realistic conclusion. To summarize, continued research is recommended in the fundamentals of the science related to genetic engineering and specific topics to cover knowledge gaps. In the meantime, the team also advocates continued development of related processes which can be linked to pollution control and other real world

  4. Krypton retention on solid adsorbents

    International Nuclear Information System (INIS)

    Monson, P.R. Jr.

    1981-08-01

    Over a dozen prospective adsorbents for krypton were studied and evaluated with respect to adsorption capacity and cost for dissolver off-gas streams from nuclear reprocessing plants. Results show that, at subambient temperature (-40 0 to -80 0 C), the commercially available hydrogen mordenite has sufficient adsorptive capacity to be the most cost-effective material studied. Silver mordenite has a higher capacity for krypton retention, but is 50 times more expensive than hydrogen mordenite. The results indicate that a solid adsorbent system is feasible and competitive with other developing systems whih utilize fluorocarbon absorption and cryogenic distillation

  5. Technology status of hydrogen road vehicles. IEA technical report from the IEA Agreement of the production and utilization of hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Doyle, T.A.

    1998-01-31

    The report was commissioned under the Hydrogen Implementing Agreement of the International Energy Agency (IEA) and examines the state of the art in the evolving field of hydrogen-fueled vehicles for road transport. The first phase surveys and analyzes developments since 1989, when a comprehensive review was last published. The report emphasizes the following: problems, especially backfiring, with internal combustion engines (ICEs); operational safety; hydrogen handling and on-board storage; and ongoing demonstration projects. Hydrogen vehicles are receiving much attention, especially at the research and development level. However, there has been a steady move during the past 5 years toward integral demonstrations of operable vehicles intended for public roads. Because they emit few, or no greenhouse gases, hydrogen vehicles are beginning to be taken seriously as a promising solution to the problems of urban air quality. Since the time the first draft of the report was prepared (mid-19 96), the 11th World Hydrogen Energy Conference took place in Stuttgart, Germany. This biennial conference can be regarded as a valid updating of the state of the art; therefore, the 1996 results are included in the current version. Sections of the report include: hydrogen production and distribution to urban users; on-board storage and refilling; vehicle power units and drives, and four appendices titled: 'Safety questions of hydrogen storage and use in vehicles', 'Performance of hydrogen fuel in internal production engines for road vehicles, 'Fuel cells for hydrogen vehicles', and 'Summaries of papers on hydrogen vehicles'. (refs., tabs.)

  6. Krypton retention on solid adsorbents

    International Nuclear Information System (INIS)

    Monson, P.R. Jr.

    1982-01-01

    An experimental laboratory program was conducted to develop economical solid adsorbents for the retention of krypton from a dissolver off-gas stream. The study indicates that a solid adsorbent system is feasible and competitive with other developing systems which utilize fluorocarbon absorption nd cryogenic distillation. This technology may have potential applications not only in nuclear fuel reprocessing plants, but also in nuclear reactors and in environmental monitoring. Of the 13 prospective adsorbents evaluated with respect to adsorption capacity and cost, the commercially available hydrogen mordenite was the most cost-effective material at subambient temperatures (-40 0 to -80 0 C). Silver mordenite has a higher capacity for krypton retention, but is 50 times more expensive than hydrogen mordenite

  7. Hydrogen energy

    International Nuclear Information System (INIS)

    2005-03-01

    This book consists of seven chapters, which deals with hydrogen energy with discover and using of hydrogen, Korean plan for hydrogen economy and background, manufacturing technique on hydrogen like classification and hydrogen manufacture by water splitting, hydrogen storage technique with need and method, hydrogen using technique like fuel cell, hydrogen engine, international trend on involving hydrogen economy, technical current for infrastructure such as hydrogen station and price, regulation, standard, prospect and education for hydrogen safety and system. It has an appendix on related organization with hydrogen and fuel cell.

  8. Technical and economic assessment of producing hydrogen by reforming syngas from the Battelle indirectly heated biomass gasifier

    International Nuclear Information System (INIS)

    Mann, M.K.

    1995-08-01

    The technical and economic feasibility of producing hydrogen from biomass by means of indirectly heated gasification and steam reforming was studied. A detailed process model was developed in ASPEN Plus trademark to perform material and energy balances. The results of this simulation were used to size and cost major pieces of equipment from which the determination of the necessary selling price of hydrogen was made. A sensitivity analysis was conducted on the process to study hydrogen price as a function of biomass feedstock cost and hydrogen production efficiency. The gasification system used for this study was the Battelle Columbus Laboratory (BCL) indirectly heated gasifier. The heat necessary for the endothermic gasification reactions is supplied by circulating sand from a char combustor to the gasification vessel. Hydrogen production was accomplished by steam reforming the product synthesis gas (syngas) in a process based on that used for natural gas reforming. Three process configurations were studied. Scheme 1 is the full reforming process, with a primary reformer similar to a process furnace, followed by a high temperature shift reactor and a low temperature shift reactor. Scheme 2 uses only the primary reformer, and Scheme 3 uses the primary reformer and the high temperature shift reactor. A pressure swing adsorption (PSA) system is used in all three schemes to produce a hydrogen product pure enough to be used in fuel cells. Steam is produced through detailed heat integration and is intended to be sold as a by-product

  9. 78 FR 18578 - Hydrogen and Fuel Cell Technical Advisory Committee (HTAC)

    Science.gov (United States)

    2013-03-27

    ... DEPARTMENT OF ENERGY Office of Energy Efficiency and Renewable Energy Hydrogen and Fuel Cell... Energy. ACTION: Notice of Open Meeting. SUMMARY: This notice announces an open meeting of the Hydrogen... Avenue, Washington, DC 20585. SUPPLEMENTARY INFORMATION: Purpose of the Committee: The Hydrogen and Fuel...

  10. Methodology for assessing the safety of Hydrogen Systems: HyRAM 1.1 technical reference manual

    Energy Technology Data Exchange (ETDEWEB)

    Groth, Katrina; Hecht, Ethan; Reynolds, John Thomas; Blaylock, Myra L.; Erin E. Carrier

    2017-03-01

    The HyRAM software toolkit provides a basis for conducting quantitative risk assessment and consequence modeling for hydrogen infrastructure and transportation systems. HyRAM is designed to facilitate the use of state-of-the-art science and engineering models to conduct robust, repeatable assessments of hydrogen safety, hazards, and risk. HyRAM is envisioned as a unifying platform combining validated, analytical models of hydrogen behavior, a stan- dardized, transparent QRA approach, and engineering models and generic data for hydrogen installations. HyRAM is being developed at Sandia National Laboratories for the U. S. De- partment of Energy to increase access to technical data about hydrogen safety and to enable the use of that data to support development and revision of national and international codes and standards. This document provides a description of the methodology and models contained in the HyRAM version 1.1. HyRAM 1.1 includes generic probabilities for hydrogen equipment fail- ures, probabilistic models for the impact of heat flux on humans and structures, and computa- tionally and experimentally validated analytical and first order models of hydrogen release and flame physics. HyRAM 1.1 integrates deterministic and probabilistic models for quantifying accident scenarios, predicting physical effects, and characterizing hydrogen hazards (thermal effects from jet fires, overpressure effects from deflagrations), and assessing impact on people and structures. HyRAM is a prototype software in active development and thus the models and data may change. This report will be updated at appropriate developmental intervals.

  11. Thermal design and technical economical and environmental analyses of a hydrogen fired multi-objective cogeneration system

    International Nuclear Information System (INIS)

    Durmaz, A; Yilmazoglu, M. Z.; Pasoglu, A.

    2007-01-01

    Approximately 85% of rapidly increasing world energy demand is supplied by fossil fuels. Extreme usage of fossil fuels causes serious global warming and environmental problems in form of air, soil and water pollutions. The period, in which fossil fuel reserves are decreasing, energy costs are increasing rapidly and new energy sources and technologies do not exist on the horizon, can be called as the expensive and critical energy period. Hydrogen becomes a matter of primary importance as a candidate energy source and carrier in the critical energy period and beyond to solve the energy and environmental problems radically. In this respect, the main obstacle for the use of hydrogen is the high cost of hydrogen production, which is expected to be decreased in the feature. The aim of this study is to examine how hydrogen energy will be able to be integrated with the existing energy substructure with technical and economical dimensions. In this sense, a multi objective hydrogen fired gas turbine cogeneration system is designed and optimized. Technical and economical analyses depending on the load conditions and different hydrogen production cost are carried out. It is possible that the co-generated heat is to be marketed for residence and industrial plants in the surrounding at or under market prices. The produced electricity however can only be sold to the public grid at a high unit support price which is only obtainable in case of the development of new energy technologies. This price should however be kept within the nowadays supportable energy price range. The main mechanism to be used during the design stage of the system to achieve this goal is to decrease the amortization and operational costs which lead to decrease investment and fuel costs and to increase the system load factor and co-generated heat revenues

  12. Browns Ferry charcoal adsorber incident

    International Nuclear Information System (INIS)

    Mays, G.T.

    1979-01-01

    The article reviews the temperature excursion in the charcoal adsorber beds of the Browns Ferry Unit 3 off-gas system that occurred on July 17, 1977. Significant temperature increases were experienced in the charcoal adsorber beds when charcoal fines were ignited by the ignition of a combustible mixture of hydrogen and oxygen in the off-gas system. The Browns Ferry off-gas system is described, and events leading up to and surrounding the incident are discussed. The follow-up investigation by Tennessee Valley Authority and General Electric Company personnel and their recommendations for system and operational modifications are summarized

  13. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    Energy Technology Data Exchange (ETDEWEB)

    John Pratapas; Daniel Mather; Anton Kozlovsky

    2007-03-31

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen's significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an

  14. Technical and economical feasibility studies and preliminary plan of a heavy water plant by the criogenic distillation method of hydrogen

    International Nuclear Information System (INIS)

    Dias Vargas, F.

    1983-01-01

    This paper presents the pre-feasibility study of a heavy water production plant, both from the technical and economical point of view. Criogenic distillation of hydrogen is used as the final enrichment stage. The deuterium source is water treated previously by a process of enrichment based on the water-hydrogen isotopic exchange. The economical analysis is aimed at the study of the feasibility of the installation of a heavy water moderated reaction in Chile. General properties of heavy water are presented and also the various materials of its enrichment at the industrial scale. The plant itself has a first stage based on the water-hydrogen isotopic exchange procesS, where deuterium is extracted from the water by the hydrogen which is subsequently treated in a criogenic distillation stage. An important fact of the plant analysis is the calculation of heat exchangers mainly in relation to the problem posed by tHe hydrogen's low point of liquifaction. The distillation units are also treated and designed. The economic evaluation produces project diScount rates of 15.71% and 21.97%, for 25 tons/year and 40 tons/year of production capacity. The heavy water price used for these evaluation was 600 $/Kg

  15. Adsorber fires

    International Nuclear Information System (INIS)

    Holmes, W.

    1987-01-01

    The following conclusions are offered with respect to activated charcoal filter systems in nuclear power plants: (1) The use of activated charcoal in nuclear facilities presents a potential for deep-seated fires. (2) The defense-in-depth approach to nuclear fire safety requires that if an ignition should occur, fires must be detected quickly and subsequently suppressed. (3) Deep-seated fires in charcoal beds are difficult to extinguish. (4) Automatic water sprays can be used to extinguish fires rapidly and reliably when properly introduced into the burning medium. The second part of the conclusions offered are more like challenges: (1) The problem associated with inadvertent actuations of fire protection systems is not a major one, and it can be reduced further by proper design review, installation, testing, and maintenance. Eliminating automatic fire extinguishing systems for the protection of charcoal adsorbers is not justified. (2) Removal of automatic fire protection systems due to fear of inadvertent fire protection system operation is a case of treating the effect rather than the cause. On the other hand, properly maintaining automatic fire protection systems will preserve the risk of fire loss at acceptable levels while at the same time reducing the risk of damage presented by inadvertent operation of fire protection systems

  16. Ecological applications of the irradiated adsorbents

    International Nuclear Information System (INIS)

    Tusseyev, T.

    2004-01-01

    Full text: In our previous works it was shown that after irradiation some adsorbents gain new interesting properties such as increasing (or decreasing) of their adsorption capacity, selectivity in relation to some gases, change of chemical bounds of gas molecules with adsorbent surface as well as other properties. We investigated a lot of adsorbents with semiconducting and dielectric properties. A high temperature superconductor was investigated also. Adsorbents were irradiated by ultraviolet (UV) and gamma - radiation, reactor (n.γ) - radiation, α-particles (E=40-50 MeV), protons ( E=30 MeV), and also He-3 ions (E-29-60 MeV). The following techniques were used: volumetric (manometrical), mass-spectrometer and IR spectroscopic methods, and also method of electronic - paramagnetic resonance (spin paramagnetic resonance) The obtained results allow to speak about creation of new adsorbents for gas purification (clearing) from harmful impurities, gas selection into components, an increasing of adsorbing surface. Thus one more advantage of the irradiated adsorbents is that they have 'memory effect', i.e. they can be used enough long time after irradiation. In laboratory conditions we built the small-sized adsorptive pump on the basis of the irradiated zeolites which are capable to work in autonomous conditions. It was found, that some of adsorbents after irradiation gain (or lose) selectivity in relation to definite gases. So, silica gel, which one in initial state does not adsorb hydrogen, after gamma irradiation it becomes active in relation to hydrogen. Some of rare earths oxides also show selectivity in relation to hydrogen and oxygen depending on a type of irradiation. Thus, it is possible to create different absorbents, depending on a solved problem, using a way or selection of adsorbents, either of radiation type and energy, as a result obtained adsorbents can be used for various ecological purposes

  17. Final Technical Report: Hydrogen Energy in Engineering Education (H2E3)

    Energy Technology Data Exchange (ETDEWEB)

    Lehman, Peter A.; Cashman, Eileen; Lipman, Timothy; Engel, Richard A.

    2011-09-15

    Schatz Energy Research Center's Hydrogen Energy in Engineering Education curriculum development project delivered hydrogen energy and fuel cell learning experiences to over 1,000 undergraduate engineering students at five California universities, provided follow-on internships for students at a fuel cell company; and developed commercializable hydrogen teaching tools including a fuel cell test station and a fuel cell/electrolyzer experiment kit. Monitoring and evaluation tracked student learning and faculty and student opinions of the curriculum, showing that use of the curriculum did advance student comprehension of hydrogen fundamentals. The project web site (hydrogencurriculum.org) provides more information.

  18. Evaluation of Technical Feasibility of Homogeneous Charge Compression Ignition (HCCI) Engine Fueled with Hydrogen, Natural Gas, and DME

    Energy Technology Data Exchange (ETDEWEB)

    Pratapas, John; Mather, Daniel; Kozlovsky, Anton

    2013-03-31

    The objective of the proposed project was to confirm the feasibility of using blends of hydrogen and natural gas to improve the performance, efficiency, controllability and emissions of a homogeneous charge compression ignition (HCCI) engine. The project team utilized both engine simulation and laboratory testing to evaluate and optimize how blends of hydrogen and natural gas fuel might improve control of HCCI combustion. GTI utilized a state-of-the art single-cylinder engine test platform for the experimental work in the project. The testing was designed to evaluate the feasibility of extending the limits of HCCI engine performance (i.e., stable combustion, high efficiency and low emissions) on natural gas by using blends of natural gas and hydrogen. Early in the project Ricardo provided technical support to GTI as we applied their engine performance simulation program, WAVE, to our HCCI research engine. Modeling support was later provided by Digital Engines, LLC to use their proprietary model to predict peak pressures and temperatures for varying operating parameters included in the Design of Experiments test plan. Digital Engines also provided testing support for the hydrogen and natural gas blends. Prof. David Foster of University of Wisconsin-Madison participated early in the project by providing technical guidance on HCCI engine test plans and modeling requirements. The main purpose of the testing was to quantify the effects of hydrogen addition to natural gas HCCI. Directly comparing straight natural gas with the hydrogen enhanced test points is difficult due to the complexity of HCCI combustion. With the same air flow rate and lambda, the hydrogen enriched fuel mass flow rate is lower than the straight natural gas mass flow rate. However, the energy flow rate is higher for the hydrogen enriched fuel due to hydrogen’s significantly greater lower heating value, 120 mJ/kg for hydrogen compared to 45 mJ/kg for natural gas. With these caveats in mind, an

  19. Technical and economic analyses of hydrogen production via indirectly heated gasification and pyrolysis

    Energy Technology Data Exchange (ETDEWEB)

    Mann, M.K. [National Renewable Energy Laboratory, Golden, CO (United States)

    1995-09-01

    Technoeconomic analyses have been conducted on two processes to produce hydrogen from biomass: indirectly-heated gasification of biomass followed by steam reforming of the syngas, and biomass pyrolysis followed by steam reforming of the pyrolysis oil. The analysis of the gasification-based process was highly detailed, including a process flowsheet, material and energy balances calculated with a process simulation program, equipment cost estimation, and the determination of the necessary selling price of hydrogen. The pyrolysis-based process analysis was of a less detailed nature, as all necessary experimental data have not been obtained; this analysis is a follow-up to the preliminary economic analysis presented at the 1994 Hydrogen Program Review. A coproduct option in which pyrolysis oil is used to produce hydrogen and a commercial adhesive was also studied for economic viability. Based on feedstock availability estimates, three plant sizes were studied: 907 T/day, 272 T/day, and 27 T/day. The necessary selling price of hydrogen produced by steam reforming syngas from the Battelle Columbus Laboratories indirectly heated biomass gasifier falls within current market values for the large and medium size plants within a wide range of feedstock costs. Results show that the small scale plant does not produce hydrogen at economically competitive prices, indicating that if gasification is used as the upstream process to produce hydrogen, local refueling stations similar to current gasoline stations, would probably not be feasible.

  20. Hydrogen initiative: An integrated approach toward rational nanocatalyst design for hydrogen production. Technical Report-Year 1

    Energy Technology Data Exchange (ETDEWEB)

    Vlachos, Dionisios G. [Univ. of Delaware, Newark, DE (United States); Buttrey, Douglas J. [Univ. of Delaware, Newark, DE (United States); Lauterbach, Jochen A. [Univ. of Delaware, Newark, DE (United States)

    2007-03-29

    The overall objective of this grant is to develop a rational framework for the discovery of low cost, robust, and active nano-catalysts that will enable efficient hydrogen production. Our approach will be the first demonstration of integrated multiscale model, nano-catalyst synthesis, and nanoscale characterization assisted high throughput experimentation (HTE). We will initially demonstrate our approach with ammonia decomposition on noble metal catalysts. Our research focuses on many elements of the Hydrogen Initiative in the Focus Area of “Design of Catalysts at the Nanoscale’. It combines high-throughput screening methods with various nanostructure synthesis protocols, advanced measurements, novel in situ and ex situ characterization techniques, and multiscale theory, modeling and simulation. This project directly addresses several of the long-term goals of the DOE/BES program. In particular, new nanoscale catalytic materials will be synthesized, characterized and modeled for the production of hydrogen from ammonia and a computational framework will be developed for efficient extraction of information from experimental data and for rational design of catalysts whose impact goes well beyond the proposed hydrogen production project. In the first year of the grant, we have carried out HTE screening using a 16 parallel microreactor coupled with an FTIR analysis system. We screened nearly twenty single metals and several bimetallic catalysts as a function of temperature, catalyst loading, inlet composition, and temperature (order of 400 experiments). We have found that Ru is the best single metal catalyst and no better catalysts were found among the library of bimetallics we have created so far. Furthermore, we have investigated promoting effects (i.e., K, Cs, and Ba) of the Ru catalyst. We have found that K is the dominant promoter of increased Ru activity. Response surface experimental design has led to substantial improvements of the Ru catalyst with promotion

  1. Final Technical Report: Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project

    Energy Technology Data Exchange (ETDEWEB)

    Ronald Grasman

    2011-12-31

    This report summarizes the work conducted under U.S. Department of Energy (DOE) under contract DE-FC36-04GO14285 by Mercedes-Benz & Research Development, North America (MBRDNA), Chrysler, Daimler, Mercedes Benz USA (MBUSA), BP, DTE Energy and NextEnergy to validate fuel cell technologies for infrastructure, transportation as well as assess technology and commercial readiness for the market. The Mercedes Team, together with its partners, tested the technology by operating and fueling hydrogen fuel cell vehicles under real world conditions in varying climate, terrain and driving conditions. Vehicle and infrastructure data was collected to monitor the progress toward the hydrogen vehicle and infrastructure performance targets of $2.00 to 3.00/gge hydrogen production cost and 2,000-hour fuel cell durability. Finally, to prepare the public for a hydrogen economy, outreach activities were designed to promote awareness and acceptance of hydrogen technology. DTE, BP and NextEnergy established hydrogen filling stations using multiple technologies for on-site hydrogen generation, storage and dispensing. DTE established a hydrogen station in Southfield, Michigan while NextEnergy and BP worked together to construct one hydrogen station in Detroit. BP constructed another fueling station in Burbank, California and provided a full-time hydrogen trailer at San Francisco, California and a hydrogen station located at Los Angeles International Airport in Southern, California. Stations were operated between 2005 and 2011. The Team deployed 30 Gen I Fuel Cell Vehicles (FCVs) in the beginning of the project. While 28 Gen I F-CELLs used the A-Class platform, the remaining 2 were Sprinter delivery vans. Fuel cell vehicles were operated by external customers for real-world operations in various regions (ecosystems) to capture various driving patterns and climate conditions (hot, moderate and cold). External operators consisted of F-CELL partner organizations in California and Michigan

  2. The hydrogen resource. Productive, technical and economic analysis; La risorsa idrogeno: analisi produttiva tecnica ed economica

    Energy Technology Data Exchange (ETDEWEB)

    De Fronzo, G. [Lecce Univ., Lecce (Italy). Dipt. di Scienze Economiche, Matematico-Statistiche, Economici-Aziendali

    2000-02-01

    Diffusion of hydrogen as an energetic vector meets with a lot of obstacles that don't depend on available raw material, but on hydrogen combination with other elements. It is necessary, therefore, to separate hydrogen picking out the available different technologies to have different pure hydrogen of variable quantities. Besides, its diffusion as fuel is limited because of the great production cost compared to fuels sprung from petroleum. Hydrogen used on a large scale could have advantages on the environment and occupation, but there are economic and politic obstacles to limit its diffusion. Future of economic system, based on hydrogen as the main energetic vector, will depend on the programme that national and international qualified governing bodies will be able to do. [Italian] L'articolo analizza l'uso dell'idrogeno come risorsa dal punto di vista tecnico ed economico. Si discute la relazione con i programmi che governi nazionali sapranno mettere in campo per il suo sfruttamento.

  3. Hydrogen.

    Science.gov (United States)

    Bockris, John O'M

    2011-11-30

    The idea of a "Hydrogen Economy" is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO₂ in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H₂ from the electrolyzer. Methanol made with CO₂ from the atmosphere is a zero carbon fuel created from inexhaustible components from the atmosphere. Extensive work on the splitting of water by bacteria shows that if wastes are used as the origin of feed for certain bacteria, the cost for hydrogen becomes lower than any yet known. The first creation of hydrogen and electricity from light was carried out in 1976 by Ohashi et al. at Flinders University in Australia. Improvements in knowledge of the structure of the semiconductor-solution system used in a solar breakdown of water has led to the discovery of surface states which take part in giving rise to hydrogen (Khan). Photoelectrocatalysis made a ten times increase in the efficiency of the photo production of hydrogen from water. The use of two electrode cells; p and n semiconductors respectively, was first introduced by Uosaki in 1978. Most photoanodes decompose during the photoelectrolysis. To avoid this, it has been necessary to create a transparent shield between the semiconductor and its electronic properties and the solution. In this way, 8.5% at 25 °C and 9.5% at 50 °C has been reached in the photo dissociation of water (GaP and InAs) by Kainthla and Barbara Zeleney in 1989. A large consortium has been funded by the US government at the California Institute of Technology under the direction of Nathan Lewis. The decomposition of water by light is the main aim of this group. Whether light will be the origin of the post fossil fuel supply of energy may be questionable, but the maximum program in this direction is likely to come from Cal. Tech.

  4. Texas Hydrogen Highway Fuel Cell Hybrid Bus and Fueling Infrastructure Technology Showcase - Final Scientific/Technical Report

    Energy Technology Data Exchange (ETDEWEB)

    Hitchcock, David

    2012-06-29

    The Texas Hydrogen Highway project has showcased a hydrogen fuel cell transit bus and hydrogen fueling infrastructure that was designed and built through previous support from various public and private sector entities. The aim of this project has been to increase awareness among transit agencies and other public entities on these transportation technologies, and to place such technologies into commercial applications, such as a public transit agency. The initial project concept developed in 2004 was to show that a skid-mounted, fully-integrated, factory-built and tested hydrogen fueling station could be used to simplify the design, and lower the cost of fueling infrastructure for fuel cell vehicles. The approach was to design, engineer, build, and test the integrated fueling station at the factory then install it at a site that offered educational and technical resources and provide an opportunity to showcase both the fueling station and advanced hydrogen vehicles. The two primary technology components include: Hydrogen Fueling Station: The hydrogen fueling infrastructure was designed and built by Gas Technology Institute primarily through a funding grant from the Texas Commission on Environmental Quality. It includes hydrogen production, clean-up, compression, storage, and dispensing. The station consists of a steam methane reformer, gas clean-up system, gas compressor and 48 kilograms of hydrogen storage capacity for dispensing at 5000 psig. The station is skid-mounted for easy installation and can be relocated if needed. It includes a dispenser that is designed to provide temperaturecompensated fills using a control algorithm. The total station daily capacity is approximately 50 kilograms. Fuel Cell Bus: The transit passenger bus built by Ebus, a company located in Downey, CA, was commissioned and acquired by GTI prior to this project. It is a fuel cell plug-in hybrid electric vehicle which is ADA compliant, has air conditioning sufficient for Texas operations

  5. Microstructural studies of hydrogen and deuterium in bcc refractory metals. Final technical report

    International Nuclear Information System (INIS)

    Moss, S.C.

    1984-04-01

    Research was conducted on the microstructural atomic arrangements in alloys of hydrogen and deuterium with bcc refractory metals with emphasis on V and Nb. Because these are interstitial phases in which the host metal lattice is substantially deformed by the incorporation of the H(D) atoms, there are pronounced x-ray scattering effects. X-ray diffraction was used, with neutron scattering providing useful corollary data. One objective was to determine the phase relations, solid solution structures and phase transitions in metal-hydride alloys which depend upon the hydrogen-hydrogen interaction via the displacement field of the metal atoms. This has often included the elucidation of subtle thermodynamic properties (as in critical wetting) which are revealed in structural studies. Crystals were supplied for positron annihilation studies of the Fermi surface of H-Ta alloys which have revealed significant electronic trends. Work on alkali-graphite intercalates was initiated

  6. Technical feasibility and financial analysis of hybrid wind-photovoltaic system with hydrogen storage for Cooma

    Energy Technology Data Exchange (ETDEWEB)

    Shakya, B.D.; Aye, L. [Melbourne Univ., Victoria (Australia). Dept. of Civil and Environmental Engineering; Musgrave, P. [Snowy Hydro Ltd., Cooma, NSW (Australia)

    2005-01-01

    The feasibility of a stand-alone hybrid wind-photovoltaic (PV) system incorporating compressed hydrogen gas storage was studied for Cooma (Australia). Cooma has an average annual solar and wind energy availability of 1784 and 932 kWh/m{sup 2}, respectively. A system with 69 kWh{sub e}/day (load) and 483 kWh{sub e}(storage) was studied. Hydrogen is generated in electrolysers using excess electricity from the system. The system components were selected according to their availability and cost. The 'discounted cash flow' method, with the 'levelized energy cost' (LEC) as a financial indicator was used for analysis. Configurations with PV% of 100, 60, 12 and zero were analysed. The lowest LEC of AU $2.52/kWh{sub e} was found for 100% PV. The cost of hydrogen generation from 100% PV was AU $692/GJ of hydrogen. Fifty-two percent of the total project costs were due to the electrolyser. Hence, a reduction in the electrolyser cost would reduce the cost of the overall system. (Author)

  7. Hydrogen

    Directory of Open Access Journals (Sweden)

    John O’M. Bockris

    2011-11-01

    Full Text Available The idea of a “Hydrogen Economy” is that carbon containing fuels should be replaced by hydrogen, thus eliminating air pollution and growth of CO2 in the atmosphere. However, storage of a gas, its transport and reconversion to electricity doubles the cost of H2 from the electrolyzer. Methanol made with CO2 from the atmosphere is a zero carbon fuel created from inexhaustible components from the atmosphere. Extensive work on the splitting of water by bacteria shows that if wastes are used as the origin of feed for certain bacteria, the cost for hydrogen becomes lower than any yet known. The first creation of hydrogen and electricity from light was carried out in 1976 by Ohashi et al. at Flinders University in Australia. Improvements in knowledge of the structure of the semiconductor-solution system used in a solar breakdown of water has led to the discovery of surface states which take part in giving rise to hydrogen (Khan. Photoelectrocatalysis made a ten times increase in the efficiency of the photo production of hydrogen from water. The use of two electrode cells; p and n semiconductors respectively, was first introduced by Uosaki in 1978. Most photoanodes decompose during the photoelectrolysis. To avoid this, it has been necessary to create a transparent shield between the semiconductor and its electronic properties and the solution. In this way, 8.5% at 25 °C and 9.5% at 50 °C has been reached in the photo dissociation of water (GaP and InAs by Kainthla and Barbara Zeleney in 1989. A large consortium has been funded by the US government at the California Institute of Technology under the direction of Nathan Lewis. The decomposition of water by light is the main aim of this group. Whether light will be the origin of the post fossil fuel supply of energy may be questionable, but the maximum program in this direction is likely to come from Cal. Tech.

  8. Thermodynamic foundations of applications of ab initio methods for determination of the adsorbate equilibria: hydrogen at the GaN(0001) surface.

    Science.gov (United States)

    Kempisty, Pawel; Strąk, Paweł; Sakowski, Konrad; Kangawa, Yoshihiro; Krukowski, Stanisław

    2017-11-08

    Thermodynamic foundations of ab initio modeling of vapor-solid and vapor-surface equilibria are introduced. The chemical potential change is divided into enthalpy and entropy terms. The enthalpy path passes through vapor-solid transition at zero temperature. The entropy path avoids the singular point at zero temperature passing a solid-vapor transition under normal conditions, where evaporation entropy is employed. In addition, the thermal changes are calculated. The chemical potential difference contribution of the following terms: vaporization enthalpy, vaporization entropy, the temperature-entropy related change, the thermal enthalpy change and mechanical pressure is obtained. The latter term is negligibly small for the pressure typical for epitaxy. The thermal enthalpy change is two orders smaller than the first three terms which have to be taken into account explicitly. The configurational vaporization entropy change is derived for adsorption processes. The same formulation is derived for vapor-surface equilibria using hydrogen at the GaN(0001) surface as an example. The critical factor is the dependence of the enthalpy of evaporation (desorption energy) on the pinning of the Fermi level bringing a drastic change of the value from 2.24 eV to -2.38 eV. In addition it is shown that entropic contributions considerable change the hydrogen equilibrium pressure over the GaN(0001) surface by several orders of magnitude. Thus a complete and exact formulation of vapor-solid and vapor-surface equilibria is presented.

  9. Methyl iodide tests on used adsorbents

    International Nuclear Information System (INIS)

    Kovach, J.L.

    1993-01-01

    This paper discusses the history of events leading to the current problems in radioiodine test conditions. These radioiodine tests are performed in the adsorbent media from both safety and non-safety related Nuclear Air Treatment Systems (NATS). The main problem addressed is that currently there are still numerous plant technical specifications for NATS which reference outdated test protocols for the surveillance testing of the radioactive methyl iodide performance of the adsorbents. Recommendations for correcting the test condition problems are presented. 7 refs

  10. Develop improved metal hydride technology for the storage of hydrogen. Final technical report

    Energy Technology Data Exchange (ETDEWEB)

    Sapru, K.

    1998-12-04

    The overall objective was to develop commercially viable metal hydrides capable of reversibly storing at least 3 wt.% hydrogen for use with PEM fuel cells and hydrogen fueled internal combustion engine (HICE) applications. Such alloys are expected to result in system capacities of greater than 2 wt.%, making metal hydride storage systems (MHSS`s) a practical means of supplying hydrogen for many consumer applications. ECD`s (Energy Conversion Devices, Inc.) past work on sputtered thin films of transition metal-based alloys led to the commercialization of it`s nickel/metal hydride batteries, and similar work on thin film Mg-based alloys demonstrated potential to achieve very high gravimetric and volumetric energy densities approaching 2,500 Wh/Kg and 2,500 Wh/M{sup 3} respectively. Under this 2-year cost shared project with the DOE, the authors have successfully demonstrated the feasibility of scaling up the Mg-based hydrides from thin film to bulk production without substantial loss of storage capacity. ECD made progress in alloy development by means of compositional and process modification. Processes used include Mechanical Alloying, Melt spinning and novel Gas Phase Condensation. It was showed that the same composition when prepared by melt-spinning resulted in a more homogeneous material having a higher PCT plateau pressure as compared to mechanical alloying. It was also shown that mechanically alloyed Mg-Al-Zn results in much higher plateau pressures, which is an important step towards reducing the desorption temperature. While significant progress has been made during the past two years in alloy development and understanding the relationship between composition, structure, morphology, and processing parameters, additional R and D needs to be performed to achieve the goals of this work.

  11. Final Technical Report for EE0006091: H2Pump Hydrogen Recycling System Demonstration

    Energy Technology Data Exchange (ETDEWEB)

    Staudt, Rhonda [H2Pump LLC, Latham, NY (United States)

    2017-02-21

    The objective of this project is to demonstrate the product readiness and to quantify the benefits and customer value proposition of H2Pump’s Hydrogen Recycling System (HRS-100™) by installing and analyzing the operation of multiple prototype 100-kg per day systems in real world customer locations. The data gathered will be used to measure reliability, demonstrate the value proposition to customers, and validate our business model. H2Pump will install, track and report multiple field demonstration systems in industrial heat treating and semi-conductor applications. The customer demonstrations will be used to develop case studies and showcase the benefits of the technology to drive market adoption.

  12. Interplay of adsorbate-adsorbate and adsorbate-substrate interactions in self-assembled molecular surface nanostructures

    DEFF Research Database (Denmark)

    Schnadt, Joachim; Xu, Wei; Vang, Ronnie Thorbjørn

    2010-01-01

    a large tolerance to monatomic surface steps on the Ag(110) surface. The observed behaviour is explained in terms of strong intermolecular hydrogen bonding and a strong surface-mediated directionality, assisted by a sufficient degree of molecular backbone flexibility. In contrast, the same kind of step......-edge crossing is not observed when the molecules are adsorbed on the isotropic Ag(111) or more reactive Cu(110) surfaces. On Ag(111), similar 1-D assemblies are formed to those on Ag(110), but they are oriented along the step edges. On Cu(110), the carboxylic groups of NDCA are deprotonated and form covalent...... bonds to the surface, a situation which is also achieved on Ag(110) by annealing to 200 degrees C. These results show that the formation of particular self-assembled molecular nanostructures depends significantly on a subtle balance between the adsorbate-adsorbate and adsorbate-substrate interactions...

  13. Theoretical Insight of Physical Adsorption for a Single Component Adsorbent + Adsorbate System: II. The Henry Region

    KAUST Repository

    Chakraborty, Anutosh

    2009-07-07

    The Henry coefficients of a single component adsorbent + adsorbate system are calculated from experimentally measured adsorption isotherm data, from which the heat of adsorption at zero coverage is evaluated. The first part of the papers relates to the development of thermodynamic property surfaces for a single-component adsorbent + adsorbate system1 (Chakraborty, A.; Saha, B. B.; Ng, K. C.; Koyama, S.; Srinivasan, K. Langmuir 2009, 25, 2204). A thermodynamic framework is presented to capture the relationship between the specific surface area (Ai) and the energy factor, and the surface structural and the surface energy heterogeneity distribution factors are analyzed. Using the outlined approach, the maximum possible amount of adsorbate uptake has been evaluated and compared with experimental data. It is found that the adsorbents with higher specific surface areas tend to possess lower heat of adsorption (ΔH°) at the Henry regime. In this paper, we have established the definitive relation between Ai and ΔH° for (i) carbonaceous materials, metal organic frameworks (MOFs), carbon nanotubes, zeolites + hydrogen, and (ii) activated carbons + methane systems. The proposed theoretical framework of At and AH0 provides valuable guides for researchers in developing advanced porous adsorbents for methane and hydrogen uptake. © 2009 American Chemical Society.

  14. Modeling adsorption: Investigating adsorbate and adsorbent properties

    Science.gov (United States)

    Webster, Charles Edwin

    1999-12-01

    Surface catalyzed reactions play a major role in current chemical production technology. Currently, 90% of all chemicals are produced by heterogeneously catalyzed reactions. Most of these catalyzed reactions involve adsorption, concentrating the substrate(s) (the adsorbate) on the surface of the solid (the adsorbent). Pore volumes, accessible surface areas, and the thermodynamics of adsorption are essential in the understanding of solid surface characteristics fundamental to catalyst and adsorbent screening and selection. Molecular properties such as molecular volumes and projected molecular areas are needed in order to convert moles adsorbed to surface volumes and areas. Generally, these molecular properties have been estimated from bulk properties, but many assumptions are required. As a result, different literature values are employed for these essential molecular properties. Calculated molar volumes and excluded molecular areas are determined and tabulated for a variety of molecules. Molecular dimensions of molecules are important in the understanding of molecular exclusion as well as size and shape selectivity, diffusion, and adsorbent selection. Molecular dimensions can also be used in the determination of the effective catalytic pore size of a catalyst. Adsorption isotherms, on zeolites, (crystalline mineral oxides) and amorphous solids, can be analyzed with the Multiple Equilibrium Analysis (MEA) description of adsorption. The MEA produces equilibrium constants (Ki), capacities (ni), and thermodynamic parameters (enthalpies, ΔHi, and entropies, ΔSi) of adsorption for each process. Pore volumes and accessible surface areas are calculated from the process capacities. Adsorption isotherms can also be predicted for existing and new adsorbate-adsorbent systems with the MEA. The results show that MEA has the potential of becoming a standard characterization method for microporous solids that will lead to an increased understanding of their behavior in gas

  15. Advantage of fast reacting adsorbents like humic acids for the recovery of uranium from seawater

    International Nuclear Information System (INIS)

    Denzinger, H.; Schnell, C.; Heitkamp, D.; Wagener, K.

    1980-01-01

    This report is divided into two sections. The first part comprises experimental data of humic acid adsorbers; whereas, the second concerns design parameter and costs of a recovery plant using fast reacting adsorbents. Summarizing the experimental results, hydrogen-loaded humic acids on carriers show an exceptionally fast kinetics of uranium fixation in seawater which is practically temperature independent. This fast adsorption performance may be maintained in a technical recovery process if care is taken to minimize slow diffraction controlled steps preceding the uranium fixation reaction. When humic acid was used instead of titanium hydroxide in the recovery plant, there was a decrease of investment and production costs of about 50%. However, there was a higher percentage of energy costs, i.e., electric power consumption and investments for pumps

  16. Improved estimates of separation distances to prevent unacceptable damage to nuclear power plant structures from hydrogen detonation for gaseous hydrogen storage. Technical report

    International Nuclear Information System (INIS)

    1994-05-01

    This report provides new estimates of separation distances for nuclear power plant gaseous hydrogen storage facilities. Unacceptable damage to plant structures from hydrogen detonations will be prevented by having hydrogen storage facilities meet separation distance criteria recommended in this report. The revised standoff distances are based on improved calculations on hydrogen gas cloud detonations and structural analysis of reinforced concrete structures. Also, the results presented in this study do not depend upon equivalencing a hydrogen detonation to an equivalent TNT detonation. The static and stagnation pressures, wave velocity, and the shock wave impulse delivered to wall surfaces were computed for several different size hydrogen explosions. Separation distance equations were developed and were used to compute the minimum separation distance for six different wall cases and for seven detonating volumes (from 1.59 to 79.67 lbm of hydrogen). These improved calculation results were compared to previous calculations. The ratio between the separation distance predicted in this report versus that predicted for hydrogen detonation in previous calculations varies from 0 to approximately 4. Thus, the separation distances results from the previous calculations can be either overconservative or unconservative depending upon the set of hydrogen detonation parameters that are used. Consequently, it is concluded that the hydrogen-to-TNT detonation equivalency utilized in previous calculations should no longer be used

  17. Onboard Hydrogen/Helium Sensors in Support of the Global Technical Regulation: An Assessment of Performance in Fuel Cell Electric Vehicle Crash Tests

    Energy Technology Data Exchange (ETDEWEB)

    Post, M. B.; Burgess, R.; Rivkin, C.; Buttner, W.; O' Malley, K.; Ruiz, A.

    2012-09-01

    Automobile manufacturers in North America, Europe, and Asia project a 2015 release of commercial hydrogen fuel cell powered light-duty road vehicles. These vehicles will be for general consumer applications, albeit initially in select markets but with much broader market penetration expected by 2025. To assure international harmony, North American, European, and Asian regulatory representatives are striving to base respective national regulations on an international safety standard, the Global Technical Regulation (GTR), Hydrogen Fueled Vehicle, which is part of an international agreement pertaining to wheeled vehicles and equipment for wheeled vehicles.

  18. Testing a technical-scale counterflow compact heat exchanger for the separation of uranium hexafluoride from hydrogen

    International Nuclear Information System (INIS)

    Hornberger, P.; Seidel, D.; Steinhaus, H.

    1981-07-01

    When enriching the light uranium isotope U-235 according to the separation nozzle method, UF 6 and light auxiliary gas (H 2 ) must be separated from each other at the head as well as at the shoulder of the cascade. After pre-separation at a special separation nozzle stage, fine separation is planned by means of a low-temperature separator made as a compact heat exchanger. This report describes first testing under process conditions of a representative section of the separator blocks intended for technical-scale operation. It is proved that the rated loading capacity is attained while the residual UF 6 concentration contained in the escaping hydrogen can be lowered down to values less than 1 ppm. It is further shown that the requirement of constant pressure drop at the separator, which is decisive for the smooth interplay of preseparator stage and low-temperature separator, can be imposed by direct control of the supply of the refrigerating medium through the variable to be kept constant. A concept of control is proposed for industrial application necessitating the operation of several low-temperature separators staggered in terms of time. This concept allows the relatively simple optimum utilization of the separator capacity even under variable operating conditions. (orig.) [de

  19. Energy policy conference on the technical-economical stakes of hydrogen as future energy vector; Conference de politique energetique sur les enjeux technico-economiques de l'hydrogene comme vecteur energetique

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2002-01-01

    This document is the report of the conference meeting jointly organized by the French general plan commission and the general direction of energy and raw materials on the technical-economical stakes of hydrogen as future energy source, and in particular of hydrogen fuel-cells for cogeneration and vehicle applications: 1 - presentation of the general context: status of the hydrogen industry, French R and D and industrial actors, international status; 2 - competition or association with fossil fuels: which opportunities for hydrogen, recall of the 2020 and 2050 energy prospects, impact of hydrogen on climate change, energy efficiency reference of vehicles, CO{sub 2} emissions 'from the well to the wheel' for the different energy sources, perspectives of hydrogen fuels; 3 - main results of the study carried out by the CEREN on the prospects of stationary fuel cells in France: description of the study, concrete case of a 500 beds hospital, economic and environmental conclusions. The transparencies corresponding to the 3 points above are attached to the report. (J.S.)

  20. The Dynamics and Structures of Adsorbed Surfaces

    DEFF Research Database (Denmark)

    Nielsen, M; Ellenson, W. D.; McTague, J. P.

    1978-01-01

    . Elastic neutron diffraction measurements, determining the two-dimensional structural ordering of the adsorbed films, have been performed on layers of N2, Ar, H2, D2, O2, Kr, and He. Measurements on layers of larger molecules such as CD4 and ND3 have also been reported. Inelastic neutron scattering...... measurements, studying the dynamics of the adsorbed films are only possible in a few especially favourable cases such as 36Ar and D2 films, where the coherent phonon scattering cross-sections are very large. In other cases incoherent scattering from hydrogen can give information about e.g. the mobility...

  1. TESTING OF CARBONACEOUS ADSORBENTS FOR REMOVAL OF POLLUTANTS FROM WATER

    Directory of Open Access Journals (Sweden)

    RAISA NASTAS

    2012-03-01

    Full Text Available Testing of carbonaceous adsorbents for removal of pollutants from water. Relevant direction for improving of quality of potable water is application of active carbons at various stages of water treatments. This work includes complex research dealing with testing of a broad spectrum of carbonaceous adsorbents for removal of hydrogen sulfide and nitrite ions from water. The role of the surface functional groups of carbonaceous adsorbents, their acid-basic properties, and the influence of the type of impregnated heteroatom (N, O, or metals (Fe, Cu, Ni, on removal of hydrogen sulfide species and nitrite ions have been researched. The efficiency of the catalyst obtained from peach stones by impregnation with Cu2+ ions of oxidized active carbon was established, being recommended for practical purposes to remove the hydrogen sulfide species from the sulfurous ground waters. Comparative analysis of carbonaceous adsorbents reveals the importance of surface chemistry for oxidation of nitrite ions.

  2. Regenerative adsorbent heat pump

    Science.gov (United States)

    Jones, Jack A. (Inventor)

    1991-01-01

    A regenerative adsorbent heat pump process and system is provided which can regenerate a high percentage of the sensible heat of the system and at least a portion of the heat of adsorption. A series of at least four compressors containing an adsorbent is provided. A large amount of heat is transferred from compressor to compressor so that heat is regenerated. The process and system are useful for air conditioning rooms, providing room heat in the winter or for hot water heating throughout the year, and, in general, for pumping heat from a lower temperature to a higher temperature.

  3. Final Technical Report for GO15056 Millennium Cell: Development of an Advanced Chemical Hydrogen Storage and Generation System

    Energy Technology Data Exchange (ETDEWEB)

    Moreno, Oscar [Millennium Cell Inc., Eatontown, NJ (United States)

    2017-02-22

    The objectives of this project are to increase system storage capacity by improving hydrogen generation from concentrated sodium borohydride, with emphasis on reactor and system engineering; to complete a conceptual system design based on sodium borohydride that will include key technology improvements to enable a hydrogen fuel system that will meet the systembased storage capacity of 1.2 kWh/L (36 g H2/L) and 1.5 kWh/kg (45 g H2/kg), by the end of FY 2007; and to utilize engineering expertise to guide Center research in both off-board chemical hydride regeneration and on-board hydrogen generation systems.

  4. Hydrogen storage using microporous carbon materials

    International Nuclear Information System (INIS)

    Buczek, B.; Wolak, E.

    2005-01-01

    higher temperatures than liquefaction [3]. Last years have brought the interest in hydrogen storage in porous carbon materials, caused by the design and accessibility of new materials, such as fullerenes, carbon nano-tubes and nano-fibers. In particular the tubular carbon structures are perspective highly adsorbing materials, for their surface adsorption (on the internal and external surface of the nano-tubes), and for the effect of capillary condensation [4]. Data presented in Table 1 show that the amount of hydrogen adsorbed on these new materials depends of their modification and on the type of carbon precursor [5]. In this work the concept of hydrogen storage by adsorption was analyzed. The discussion is based on measurements of hydrogen adsorption on commercial active carbon in the temperature range 77 - 298 K at pressures up to 4 MPa. The amount of gas that can be stored in an adsorption system depends on the adsorbent characteristics and the operating conditions. Adsorption method was compared with another one taking into account both technical and economical aspects. The results show that the adsorption technique could provide a viable method for hydrogen storage. [1]G. D. Berry, A. D. Pastemak, G. D. Rambach, J. R. Smith, N. Schock, Energy. 21, 289, 1996; [2]L. Czepirski, Przem. Chem. 70, 129, 1991 (in Polish); [3]B. Buczek, L. Czepirski, Inz. Chem. Proc., 24, 545, 2003; [4]U. Huczko, Przem. Chem. 81, 19, 2002 (in Polish); [5]U. Buenger, W. Zittel, Appl. Phys. A 72, 147, 2001. (authors)

  5. Hydrogen storage using microporous carbon materials

    International Nuclear Information System (INIS)

    B Buczek; E Wolak

    2005-01-01

    temperatures than liquefaction. Last years have brought the interest in hydrogen storage in porous carbon materials, caused by the design and accessibility of new materials, such as fullerenes, carbon nano-tubes and nano-fibers. In particular the tubular carbon structures are perspective highly adsorbing materials, for their surface adsorption (on the internal and external surface of the nano-tubes), and for the effect of capillary condensation. Data presented in Table 1 show that the amount of hydrogen adsorbed on these new materials depends of their modification and on the type of carbon precursor. In this work the concept of hydrogen storage by adsorption was analyzed. The discussion is based on measurements of hydrogen adsorption on commercial active carbon in the temperature range 77 - 298 K at pressures up to 4 MPa. The amount of gas that can be stored in an adsorption system depends on the adsorbent characteristics and the operating conditions. Adsorption method was compared with another one taking into account both technical and economical aspects. The results show that the adsorption technique could provide a viable method for hydrogen storage

  6. Transporting method for adsorbing tower and the adsorbing tower

    International Nuclear Information System (INIS)

    Shimokawa, Nobuhiro.

    1996-01-01

    A cylindrical plastic bag is disposed to the upper surface of an adsorbing tower so as to surround a suspending piece. One opening of the bag is sealed, and other opening is secured in a sealed state to a bag holding portion disposed to glove box at a gate for the adsorbing tower box. The adsorbing tower is transported into the glove box, and after the completion of the operation of the adsorbing tower, the adsorbing tower is taken out in a state that the bag is restricted and sealed at a portion below the adsorbing tower. The bag may be made of a vinyl plastic, the bag holding portion may be a short-cylindrical protrusion, and may have an O-ring groove at the outer surface. Even if the adsorbing tower is heavy, the adsorbing tower can be carried out easily in a state where it is sealed gas tightly. (N.H.)

  7. Production of Hydrogen by Superadiabatic Decomposition of Hydrogen Sulfide - Final Technical Report for the Period June 1, 1999 - September 30, 2000

    Energy Technology Data Exchange (ETDEWEB)

    Rachid B. Slimane; Francis S. Lau; Javad Abbasian

    2000-10-01

    The objective of this program is to develop an economical process for hydrogen production, with no additional carbon dioxide emission, through the thermal decomposition of hydrogen sulfide (H{sub 2}S) in H{sub 2}S-rich waste streams to high-purity hydrogen and elemental sulfur. The novel feature of the process being developed is the superadiabatic combustion (SAC) of part of the H{sub 2}S in the waste stream to provide the thermal energy required for the decomposition reaction such that no additional energy is required. The program is divided into two phases. In Phase 1, detailed thermochemical and kinetic modeling of the SAC reactor with H{sub 2}S-rich fuel gas and air/enriched air feeds is undertaken to evaluate the effects of operating conditions on exit gas products and conversion efficiency, and to identify key process parameters. Preliminary modeling results are used as a basis to conduct a thorough evaluation of SAC process design options, including reactor configuration, operating conditions, and productivity-product separation schemes, with respect to potential product yields, thermal efficiency, capital and operating costs, and reliability, ultimately leading to the preparation of a design package and cost estimate for a bench-scale reactor testing system to be assembled and tested in Phase 2 of the program. A detailed parametric testing plan was also developed for process design optimization and model verification in Phase 2. During Phase 2 of this program, IGT, UIC, and industry advisors UOP and BP Amoco will validate the SAC concept through construction of the bench-scale unit and parametric testing. The computer model developed in Phase 1 will be updated with the experimental data and used in future scale-up efforts. The process design will be refined and the cost estimate updated. Market survey and assessment will continue so that a commercial demonstration project can be identified.

  8. Hydrogen fuel. Uses

    International Nuclear Information System (INIS)

    Darkrim-Lamari, F.; Malbrunot, P.

    2006-01-01

    Hydrogen is a very energetic fuel which can be used in combustion to generate heat and mechanical energy or which can be used to generate electricity and heat through an electrochemical reaction with oxygen. This article deals with the energy conversion, the availability and safety problems linked with the use of hydrogen, and with the socio-economical consequences of a generalized use of hydrogen: 1 - hydrogen energy conversion: hydrogen engines, aerospace applications, fuel cells (principle, different types, domains of application); 2 - hydrogen energy availability: transport and storage (gas pipelines, liquid hydrogen, adsorbed and absorbed hydrogen in solid materials), service stations; 3 - hazards and safety: flammability, explosibility, storage and transport safety, standards and regulations; 4 - hydrogen economy; 5 - conclusion. (J.S.)

  9. DGEMP/CGP energy policy lecture cycle - technical and economical stakes of hydrogen as an energy carrier

    International Nuclear Information System (INIS)

    Alleau, T.; Freund, E.; Coiffard, J.

    2002-01-01

    Hydrogen is attracting a lot a interest from energy specialists, in particular because supply safety issues are back on the agendas. One of the most promising applications seems to be the 'combustible cells', which changes hydrogen into electricity and heat in various applications: 'mobile', as an alternative to electric cells, for instance in telephones or lap-top computers, 'stationary' for producing electricity and heat, including small and medium voltage, and 'transport' with a high number of light vehicle and even bus prototypes. (authors)

  10. Results of a technical analysis of the Hubble Space Telescope nickel-cadmium and nickel-hydrogen batteries

    Science.gov (United States)

    Manzo, Michelle A.

    1991-01-01

    The Hubble Space Telescope (HST) Program Office requested the expertise of the NASA Aerospace Flight Battery Systems Steering Committee (NAFBSSC) in the conduct of an independent assessment of the HST's battery system to assist in their decision of whether to fly nickel-cadmium or nickel-hydrogen batteries on the telescope. In response, a subcommittee to the NAFBSSC was organized with membership comprised of experts with background in the nickel-cadmium/nickel-hydrogen secondary battery/power systems areas. The work and recommendations of that subcommittee are presented.

  11. Residence time determination for adsorbent beds of different configurations

    Energy Technology Data Exchange (ETDEWEB)

    Otermat, J.E.; Wikoff, W.O.; Kovach, J.L.

    1995-02-01

    The residence time calculations of ASME AG-1 Code, Section FC, currently specify a screen surface area method, that is technically incorrect. Test data has been obtained on Type II adsorber trays of different configurations to establish residence time in the adsorber trays. These data indicate that the air volume/carbon volume ratio or the average screen area are more appropriate for the calculation of the residence time calculation than the currently used, smallest screen area basis.

  12. The state of physically adsorbed substances in microporous adsorbents

    International Nuclear Information System (INIS)

    Fomkin, A.A.

    1987-01-01

    Xe, Kr, Ar, CF 3 Cl, CH 4 adsorption in NaX microporous zeolite of 0.98 Na 2 OxAl 2 O 3 x2.36SiO 2 x0.02H 2 O is studied. Some properties of adsorbates (density, coefficients of expansion, enthalpy, heat capacity) are determined and discussed. The adsorbate in the microporous adsorbent is shown to be a particular state of a substance. Liniarity of adsorption isosteres and sharp changes during isosteric heat capacity of the adsorbate points to the fact that in microporous adsorbents phase transformations of the second type are possible

  13. Photochemical hydrogen production system

    International Nuclear Information System (INIS)

    Copeland, R.J.

    1990-01-01

    Both technical and economic factors affect the cost of producing hydrogen by photochemical processes. Technical factors include the efficiency and the capital and operating costs of the renewable hydrogen conversion system; economic factors include discount rates, economic life, credit for co-product oxygen, and the value of the energy produced. This paper presents technical and economic data for a system that generates on-peak electric power form photochemically produced hydrogen

  14. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor refueling: Technical progress report

    International Nuclear Information System (INIS)

    Kim, K.

    1986-01-01

    A detailed experimental study successfully demonstrates the acceleration of frozen hydrogen pellets by means of a fuseless two-stage electromagnetic railgun system. This system consists of a pneumatic hydrogen pellet injector, which freezes and pneumatically pre-accelerates (with high-pressure helium as the propellant gas) cylindrical 1.6-mm-dia by 2.15-mm-long hydrogen pellets, and a 60-cm-long, 1.6-mm-dia circular-bore electromagnetic railgun. The pellet is introduced into the railgun by means of a coupling piece, and a plasma-arc armature is created from the propellant gas by means of a very unique, fuseless, arc-initiation scheme. Railgun-accelerated hydrogen pellet velocities in excess of 1.6 km/s are achieved from pneumatically accelerated injection velocities of 800 m/s. Streak-camera and current-probe data show that the plasma-arc armature moves at a velocity proportional to the railgun current, I. Insight to this I-dependence is gained through the use of streak photography and current probes for varying bore geometries and gas pressures

  15. Final Technical Report on STTR Project DE-FG02-04ER86191 Hydrogen Cryostat for Muon Beam Cooling

    International Nuclear Information System (INIS)

    Johnson, Rolland P.

    2008-01-01

    The project was to develop cryostat designs that could be used for muon beam cooling channels where hydrogen would circulate through refrigerators and the beam-cooling channel to simultaneously refrigerate (1) high-temperature-superconductor (HTS) magnet coils, (2) cold copper RF cavities, and (3) the hydrogen that is heated by the muon beam. In an application where a large amount of hydrogen is naturally present because it is the optimum ionization cooling material, it was reasonable to explore its use with HTS magnets and cold, but not superconducting, RF cavities. In this project we developed computer programs for simulations and analysis and conducted experimental programs to examine the parameters and technological limitations of the materials and designs of Helical Cooling Channel (HCC) components (magnet conductor, RF cavities, absorber windows, heat transport, energy absorber, and refrigerant). The project showed that although a hydrogen cryostat is not the optimum solution for muon ionization cooling channels, the studies of the cooling channel components that define the cryostat requirements led to fundamental advances. In particular, two new lines of promising development were opened up, regarding very high field HTS magnets and the HS concept, that have led to new proposals and funded projects

  16. Surface treatment method for hydrogen adsorbing alloy powder and alkali secondary battery fabricated by applying the method; Suiso kyuzo gokin funmatsu no hyomen shori hoho to sorewo tekiyoshite eraeta arukari niji denchi

    Energy Technology Data Exchange (ETDEWEB)

    Nishimura, K. [Furukawa Electric Co. Ltd., Tokyo (Japan); Sawa, H. [The Furukawa Battery Co. Ltd., Yokohama (Japan)

    1997-03-07

    Corrosion of alloy proceeds in the conventional hydrogen absorbing alloy because the composing hydrogen absorbing alloy powder contacts with high concentration alkali electrolyte in the battery. Immersion into alkali aqueous solution and pulverization by metal fluoride compound of the electrode have been practiced to solve the problem, but internal resistance of the battery increases and the charge and discharge properties of the battery are deteriorated. This invention relates to a method in which hydrogen absorbing alloy electrode powder or the hydrogen alloy electrode whose main content is the said powder is contacted with alkali aqueous solution to increase the specific surface area of the hydrogen absorbing alloy powder, followed by its contact with pH3-6 acidic aqueous solution containing fluorine ions. As a result, corrosion resistance of the surface of hydrogen absorbing alloy powder after the treatment against high concentration alkali electrolyte is improved to elongate the cycle life. Salts of LiF, NaF, KF, RbF, and CsF or their hydrogen salts can be used as the supply source of fluorine ions. 3 tabs.

  17. Orientational epitaxy in adsorbed monolayers

    International Nuclear Information System (INIS)

    Novaco, A.D.; McTague, J.P.

    1977-01-01

    The ground state for adsorbed monolayers on crystalline substrates is shown to involve a definite relative orientation of the substrate and adsorbate crystal axes, even when the relative lattice parameters are incommensurate. The rotation angle which defines the structure of the monolayer-substrate system is determined by the competition between adsorbate-substrate and adsorbate-adsorbate energy terms, and is generally not a symmetry angle. Numerical predictions are presented for the rare gas-graphite systems, whose interaction potentials are rather well known. Recent LEED data for some of these systems appear to corroborate these predictions

  18. The adsorber loop concept for the contact between seawater and adsorber granulate

    International Nuclear Information System (INIS)

    Koske, P.H.; Ohlrogge, K.

    1984-01-01

    For the production of 1 kg uranium from seawater about 10 9 kg seawater - depending on the extraction efficiency - have to be processed in a production plant. Such high seawater flows have to be put through adsorber beds the area of which depends on the flow velocity of the water in the bed. For a typical polyamidoxim (PAO) adsorber granulate with a grain size distribution of 0.3 to 1.2 mm the velocity in a fluidized bed is limited to about 1 cm/s in order to prevent carry out of the adsorber material. The consequences of this rather low bed velocity are large and expensive bed areas for technical production plants. The present paper deals with the so-called ''adsorber loop concept'' in which the adsorber granulate is carried along with the seawater to be processed in a loop-like configuration and is separated again from the water before this is leaving the adsorption unit. This concept enables considerably higher seawater velocities thus reducing the bed area. Theoretical considerations are presented together with experimental results from field tests. (author)

  19. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor refueling. Technical progress report

    International Nuclear Information System (INIS)

    Kim, K.K.

    1986-01-01

    Using a tungsten-needle arc initiator in conjunction with Paschen curves characteristics hydrogen pellets have been accelerated with a two-stage electromagnetic railgun system. This scheme produced velocities on the order of 1.6 km/s. The effects on performance of the bore size have been studied. Questions of pretriggering, misfiring, plasma-arc stalling, railgun geometry, and railgun currents have been addressed. 1 tab

  20. Application of railgun principle to high-velocity hydrogen pellet injection for magnetic fusion reactor refueling: Technical progress report

    International Nuclear Information System (INIS)

    Kim, Kyekyoon.

    1987-12-01

    This paper discusses the use of a railgun accelerator to inject hydrogen pellets into a magnetic fusion reactor for refueling purposes. Specific studies in this paper include: 1.5 mm-diameter two-stage fuseless plasma-arc-driven electromagnetic railgun, construction and testing of a 3.2 mm-diameter two-stage railgun and a theoretical analysis of the behavior of a railgun plasma-arc armature inside a railgun

  1. Hazards assessment and technical actions due to the production of pressured hydrogen within a pilot photovoltaic-electrolyser-fuel cell power system for agricultural equipment

    Directory of Open Access Journals (Sweden)

    Simone Pascuzzi

    2016-06-01

    Full Text Available A pilot power system formed by photovoltaic panels, alkaline electrolyser and fuel cell stacks was designed and set up to supply the heating system of an experimental greenhouse. The aim of this paper is to analyse the main safety aspects of this power system connected to the management of the pressured hydrogen, such as the explosion limits of the mixture hydrogen-oxygen, the extension of the danger zone, the protection pressure vessels and the system to make unreactive the plant. The electrolyser unit is the core of this plant and from the safety point of view has been equipped with devices able to highlight the malfunctions before they cause damages. Alarm situations are highlighted and the production process is cut off in safe conditions in the event that the operational parameters have an abnormal deviation from the design values. Also the entire power system has been designed so that any failure to its components does not compromise the workers’ safety even if the risk analysis is in progress because technical operations are being carried out for enhancing the plant functionality, making it more suitable to the designed task of supplying electrically the greenhouse heating system during cold periods. Some experimental data pertinent to the solar radiation and the corresponding hydrogen production rate are also reported. At present it does not exist a well-established safety reference protocol to design the reliability of these types of power plants and then the assumed safety measures even if related to the achieved pilot installation, can represent an original base of reference to set up guidelines for designing the safety of power plants in the future available for agricultural purposes.

  2. Hydrogen Embrittlement

    Science.gov (United States)

    Woods, Stephen; Lee, Jonathan A.

    2016-01-01

    Hydrogen embrittlement (HE) is a process resulting in a decrease in the fracture toughness or ductility of a metal due to the presence of atomic hydrogen. In addition to pure hydrogen gas as a direct source for the absorption of atomic hydrogen, the damaging effect can manifest itself from other hydrogen-containing gas species such as hydrogen sulfide (H2S), hydrogen chloride (HCl), and hydrogen bromide (HBr) environments. It has been known that H2S environment may result in a much more severe condition of embrittlement than pure hydrogen gas (H2) for certain types of alloys at similar conditions of stress and gas pressure. The reduction of fracture loads can occur at levels well below the yield strength of the material. Hydrogen embrittlement is usually manifest in terms of singular sharp cracks, in contrast to the extensive branching observed for stress corrosion cracking. The initial crack openings and the local deformation associated with crack propagation may be so small that they are difficult to detect except in special nondestructive examinations. Cracks due to HE can grow rapidly with little macroscopic evidence of mechanical deformation in materials that are normally quite ductile. This Technical Memorandum presents a comprehensive review of experimental data for the effects of gaseous Hydrogen Environment Embrittlement (HEE) for several types of metallic materials. Common material screening methods are used to rate the hydrogen degradation of mechanical properties that occur while the material is under an applied stress and exposed to gaseous hydrogen as compared to air or helium, under slow strain rates (SSR) testing. Due to the simplicity and accelerated nature of these tests, the results expressed in terms of HEE index are not intended to necessarily represent true hydrogen service environment for long-term exposure, but rather to provide a practical approach for material screening, which is a useful concept to qualitatively evaluate the severity of

  3. Nano Structured Activated Carbon for Hydrogen Storge. Project Final Technical Report (May 2, 2005-Dec. 31, 2012)

    Energy Technology Data Exchange (ETDEWEB)

    Cabasso, Israel; Yuan, Youxin

    2013-02-27

    Development of a nanostructured synthetic carbons materials that have been synthesized by thermal-decomposition of aromatic rich polyether such as poly(ether ether ketone) (PEEK) is reported. These polymers based nanostructured carbons efficacious for gas adsorption and storage and have Brunauer-Emmett-Teller (BET) surface area of more than 3000 m2/g, and with average pore diameter of < 2nm. Surface-area, pore characteristics, and other critical variables for selecting porous materials of high gas adsorption capacities are presented. Analysis of the fragments evolved under various carbonization temperatures, and the correlation between the activation and carbonization temperatures provides a mechanistic perspective of the pore evolution during activation. Correlations between gas (N2 and H2) adsorption capacity and porous texture of the materials have been established. The materials possess excellent hydrogen storage properties, with hydrogen storage capacity up to 7.4 wt% (gravimetric) and ~ 45 g H2 L-1 (volumetric) at -196oC and 6.0 MPa.

  4. High performance Mo adsorbent PZC

    Energy Technology Data Exchange (ETDEWEB)

    Anon,

    1998-10-01

    We have developed Mo adsorbents for natural Mo(n, {gamma}){sup 99}Mo-{sup 99m}Tc generator. Among them, we called the highest performance adsorbent PZC that could adsorb about 250 mg-Mo/g. In this report, we will show the structure, adsorption mechanism of Mo, and the other useful properties of PZC when you carry out the examination of Mo adsorption and elution of {sup 99m}Tc. (author)

  5. Positronium chemistry in porous adsorbents

    International Nuclear Information System (INIS)

    Foti, G.; Nagy, L.G.; Moravcsik, G.; Schay, G.

    1981-01-01

    Kinetic studies on the annihilation of orthopositronium in porous adsorbents have been performed using lifetime spectroscopy. The positron source applied was 22 Na with 0.2 MBq activity. The adsorbents investigated were silica gels of different particle size and pore structure. The appearance of the long-lived component in the lifetime spectra can be explained by the diffusion of the orthopositronium into the pores affected by the particle size and the pore size of the adsorbent, the coverage on it and the chemical nature of the adsorbate. The long-term aim of the work is to determine and to explain these effects. (author)

  6. Technical basis for hydrogen-water chemistry: Laboratory studies of water chemistry effects on SCC [stress-corrosion-cracking

    International Nuclear Information System (INIS)

    Kassner, T.F.; Ruther, W.E.; Soppet, W.K.

    1986-10-01

    The influence of different impurities, viz., oxyacids and several chloride salts, on the stress-corrosion-cracking (SCC) of sensitized Type 304 stainless steel (SS) was investigated in constant-extension-rate-tensile (CERT) tests in 289 0 C water at a low dissolved-oxygen concentration ( 0 C in low-oxygen environments with and without sulfate at low concentrations. In these experiments, the crack growth behavior of the materials was correlated with the type and concentration of the impurities and the electrochemical potentials of Type 304 SS and platinum electrodes in the simulated hydrogen-water chemistry environments. The information suggests that better characterization of water quality, through measurement of the concentrations of individual species (SO 4 2- , NO 3 - , Cu 2+ , etc.) coupled with measurements of the corrosion and redox potentials at high temperatures will provide a viable means to monitor and ultimately improve the performance of BWR system materials

  7. Radioactive diffusion gaseous probe technique for study adsorbent structure inhomogeneity

    International Nuclear Information System (INIS)

    Zyuzin, A.Yu.; Korobkov, V.I.; Bekman, I.N.

    1990-01-01

    One of the versions of the method of diffusion gaseous probe - method of longitudinal shear in combination with autoradiography (ARG) - was used for characterising sorbents and catalysts, which are considered to be promising for reprocessing of sulfur-containing natural gases. Hydrogen sulfide, labelled with 35 S was used as diffusion radioactive probe. Zeolite granules of 4A type and granulated adsorbents on the basis of CR and AM aluminium oxides, which are industrial catalysts of Clauss reaction developed at SNEA company, were used as objects under investigation. It is shown that technique for fabrication of 4A zeolite granules leads to asymmetrical pore distribution over the granule diameter. Technique for AM granule fabrication leads to occuRrence of local inhomogeneities of the structure in the form of narrow coaxial rings with decreased or increased local adsorption ability. Granules of adsorbent of CR type are characterized by rather homogeneous structure. It is recommended to use the mentioned method for industrial adsorbent diagnosis

  8. Capture and isotopic exchange method for water and hydrogen isotopes on zeolite catalysts up to technical scale for pre-study of processing highly tritiated water

    Energy Technology Data Exchange (ETDEWEB)

    Michling, R.; Braun, A.; Cristescu, I.; Dittrich, H.; Gramlich, N.; Lohr, N. [Karlsruhe Institute of Technology, Eggenstein-Leopoldshafen (Germany); Glugla, M.; Shu, W.; Willms, S. [ITER Organization, Saint-Paul-lez-Durance (France)

    2015-03-15

    Highly tritiated water (HTW) may be generated at ITER by various processes and, due to the excessive radio toxicity, the self-radiolysis and the exceedingly corrosive property of HTW, a potential hazard is associated with its storage and process. Therefore, the capture and exchange method for HTW utilizing Molecular Sieve Beds (MSB) was investigated in view of adsorption capacity, isotopic exchange performance and process parameters. For the MSB, different types of zeolite were selected. All zeolite materials were additionally coated with platinum. The following work comprised the selection of the most efficient zeolite candidate based on detailed parametric studies during the H{sub 2}/D{sub 2}O laboratory scale exchange experiments (about 25 g zeolite per bed) at the Tritium Laboratory Karlsruhe (TLK). For the zeolite, characterization analytical techniques such as Infrared Spectroscopy, Thermogravimetry and online mass spectrometry were implemented. Followed by further investigation of the selected zeolite catalyst under full technical operation, a MSB (about 22 kg zeolite) was processed with hydrogen flow rates up to 60 mol*h{sup -1} and deuterated water loads up to 1.6 kg in view of later ITER processing of arising HTW. (authors)

  9. Black Sprayable Molecular Adsorber Coating

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of this technology project is to develop, optimize, and flight qualify a black version of the molecular adsorber coating and a conductive version...

  10. Krypton retention on solid adsorbents

    International Nuclear Information System (INIS)

    Monson, P.R. Jr.

    1980-01-01

    Radioactive krypton-85 is released to the atmosphere in the off-gas from nuclear reprocessing plants. Three main methods have been suggested for removal of krypton from off-gas streams: cryogenic distillation; fluorocarbon absorption; and adsorption on solid sorbents. Use of solid adsorbents is the least developed of these methods, but offers the potential advantages of enhanced safety and lower operating costs. An experimental laboratory program was developed that will be used to investigate systematically many solid adsorbents (such as zeolites, i.e., mordenites) for trapping krypton in air. The objective of this investigation is to find an adsorbent that is more economical than silver-exchanged mordenite. Various physical and chemical characteristics such as adsorption isotherms, decontamination factors, co-adsorption, regeneration, and the mechanism and kinetics of noble gas adsorption were used to characterize the adsorbents. In the experimental program, a gas chromatograph using a helium ionization detector was used to measure the krypton in air before and after the adsorbent bed. This method can determine directly decontamination factors greater than 100

  11. Enhanced Hydrogen Dipole Physisorption, Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Ahn, Channing [California Inst. of Technology (CalTech), Pasadena, CA (United States)

    2014-01-03

    The hydrogen gas adsorption effort at Caltech was designed to probe and apply our understanding of known interactions between molecular hydrogen and adsorbent surfaces as part of a materials development effort to enable room temperature storage of hydrogen at nominal pressure. The work we have performed over the past five years has been tailored to address the outstanding issues associated with weak hydrogen sorbent interactions in order to find an adequate solution for storage tank technology.

  12. Membrane adsorber for endotoxin removal

    Directory of Open Access Journals (Sweden)

    Karina Moita de Almeida

    Full Text Available ABSTRACT The surface of flat-sheet nylon membranes was modified using bisoxirane as the spacer and polyvinyl alcohol as the coating polymer. The amino acid histidine was explored as a ligand for endotoxins, aiming at its application for endotoxin removal from aqueous solutions. Characterization of the membrane adsorber, analysis of the depyrogenation procedures and the evaluation of endotoxin removal efficiency in static mode are discussed. Ligand density of the membranes was around 7 mg/g dry membrane, allowing removal of up to 65% of the endotoxins. The performance of the membrane adsorber prepared using nylon coated with polyvinyl alcohol and containing histidine as the ligand proved superior to other membrane adsorbers reported in the literature. The lack of endotoxin adsorption on nylon membranes without histidine confirmed that endotoxin removal was due to the presence of the ligand at the membrane surface. Modified membranes were highly stable, exhibiting a lifespan of approximately thirty months.

  13. Adsorbent Alkali Conditioning for Uranium Adsorption from Seawater. Adsorbent Performance and Technology Cost Evaluation

    International Nuclear Information System (INIS)

    Tsouris, Costas; Mayes, Richard T.; Janke, Christopher James; Dai, Sheng; Das, S.; Liao, W.P.; Kuo, Li-Jung; Wood, Jordana; Gill, Gary; Byers, Maggie Flicker; Schneider, Eric

    2015-01-01

    The Fuel Resources program of the Fuel Cycle Research and Development program of the Office of Nuclear Energy (NE) is focused on identifying and implementing actions to assure that nuclear fuel resources are available in the United States. An immense source of uranium is seawater, which contains an estimated amount of 4.5 billion tonnes of dissolved uranium. This unconventional resource can provide a price cap and ensure centuries of uranium supply for future nuclear energy production. NE initiated a multidisciplinary program with participants from national laboratories, universities, and research institutes to enable technical breakthroughs related to uranium recovery from seawater. The goal is to develop advanced adsorbents to reduce the seawater uranium recovery technology cost and uncertainties. Under this program, Oak Ridge National Laboratory (ORNL) has developed a new amidoxime-based adsorbent of high surface area, which tripled the uranium capacity of leading Japanese adsorbents. Parallel efforts have been focused on the optimization of the physicochemical and operating parameters used during the preparation of the adsorbent for deployment. A set of parameters that need to be optimized are related to the conditioning of the adsorbent with alkali solution, which is necessary prior to adsorbent deployment. Previous work indicated that alkali-conditioning parameters significantly affect the adsorbent performance. Initiated in 2014, this study had as a goal to determine optimal parameters such as base type and concentration, temperature, and duration of conditioning that maximize the uranium adsorption performance of amidoxime functionalized adsorbent, while keeping the cost of uranium production low. After base-treatment at various conditions, samples of adsorbent developed at ORNL were tested in this study with batch simulated seawater solution of 8-ppm uranium concentration, batch seawater spiked with uranium nitrate at 75-100 ppb uranium, and continuous

  14. Adsorbent Alkali Conditioning for Uranium Adsorption from Seawater. Adsorbent Performance and Technology Cost Evaluation

    Energy Technology Data Exchange (ETDEWEB)

    Tsouris, Costas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mayes, Richard T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Janke, Christopher James [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dai, Sheng [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Das, S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Liao, W. -P. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kuo, Li-Jung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wood, Jordana [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gill, Gary [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Byers, Maggie Flicker [Univ. of Texas, Austin, TX (United States); Schneider, Eric [Univ. of Texas, Austin, TX (United States)

    2015-09-30

    The Fuel Resources program of the Fuel Cycle Research and Development program of the Office of Nuclear Energy (NE) is focused on identifying and implementing actions to assure that nuclear fuel resources are available in the United States. An immense source of uranium is seawater, which contains an estimated amount of 4.5 billion tonnes of dissolved uranium. This unconventional resource can provide a price cap and ensure centuries of uranium supply for future nuclear energy production. NE initiated a multidisciplinary program with participants from national laboratories, universities, and research institutes to enable technical breakthroughs related to uranium recovery from seawater. The goal is to develop advanced adsorbents to reduce the seawater uranium recovery technology cost and uncertainties. Under this program, Oak Ridge National Laboratory (ORNL) has developed a new amidoxime-based adsorbent of high surface area, which tripled the uranium capacity of leading Japanese adsorbents. Parallel efforts have been focused on the optimization of the physicochemical and operating parameters used during the preparation of the adsorbent for deployment. A set of parameters that need to be optimized are related to the conditioning of the adsorbent with alkali solution, which is necessary prior to adsorbent deployment. Previous work indicated that alkali-conditioning parameters significantly affect the adsorbent performance. Initiated in 2014, this study had as a goal to determine optimal parameters such as base type and concentration, temperature, and duration of conditioning that maximize the uranium adsorption performance of amidoxime functionalized adsorbent, while keeping the cost of uranium production low. After base-treatment at various conditions, samples of adsorbent developed at ORNL were tested in this study with batch simulated seawater solution of 8-ppm uranium concentration, batch seawater spiked with uranium nitrate at 75-100 ppb uranium, and continuous

  15. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Kreutz, T.G.; Steinbugler, M. [Princeton Univ., NJ (United States)] [and others

    1996-10-01

    In this report the authors describe results from technical and economic assessments carried out during the past year with support from the USDOE Hydrogen R&D Program. (1) Assessment of technologies for small scale production of hydrogen from natural gas. Because of the cost and logistics of transporting and storing hydrogen, it may be preferable to produce hydrogen at the point of use from more readily available energy carriers such as natural gas or electricity. In this task the authors assess near term technologies for producing hydrogen from natural gas at small scale including steam reforming, partial oxidation and autothermal reforming. (2) Case study of developing a hydrogen vehicle refueling infrastructure in Southern California. Many analysts suggest that the first widespread use of hydrogen energy is likely to be in zero emission vehicles in Southern California. Several hundred thousand zero emission automobiles are projected for the Los Angeles Basin alone by 2010, if mandated levels are implemented. Assuming that hydrogen vehicles capture a significant fraction of this market, a large demand for hydrogen fuel could evolve over the next few decades. Refueling a large number of hydrogen vehicles poses significant challenges. In this task the authors assess near term options for producing and delivering gaseous hydrogen transportation fuel to users in Southern California including: (1) hydrogen produced from natural gas in a large, centralized steam reforming plant, and delivered to refueling stations via liquid hydrogen truck or small scale hydrogen gas pipeline, (2) hydrogen produced at the refueling station via small scale steam reforming of natural gas, (3) hydrogen produced via small scale electrolysis at the refueling station, and (4) hydrogen from low cost chemical industry sources (e.g. excess capacity in refineries which have recently upgraded their hydrogen production capacity, etc.).

  16. STUDY OF HYDROGEN SULFIDE REMOVAL FROM GROUNDWATER

    Directory of Open Access Journals (Sweden)

    T. Lupascu

    2013-06-01

    Full Text Available The process of the hydrogen sulfide removal from the underground water of the Hancesti town has been investigated. By oxygen bubbling through the water containing hydrogen sulfide, from the Hancesti well tube, sulfur is deposited in the porous structure of studied catalysts, which decreases their catalytic activity. Concomitantly, the process of adsorption / oxidation of hydrogen sulfide to sulfate take place. The kinetic research of the hydrogen sulfide removal from the Hancesti underground water, after its treatment by hydrogen peroxide, proves greater efficiency than in the case of modified carbonic adsorbents. As a result of used treatment, hydrogen sulfide is completely oxidized to sulfates

  17. Development of technical marginal conditions for the application of hydrogen as storage for renewable energies. Short version of the final report

    International Nuclear Information System (INIS)

    1993-04-01

    Due to the present experiences gained in pilot projects and by the application of hydrogen in the industry it can be expected that an equivalent safety standard will be achieved for a manifold application of hydrogen as energy carrier as e.g. in the case of natural gas or liquid gas. A decentral generation and storage of hydrogen in detached houses is not recommended in conurbation because of necessary structural measurements and safety requirements. Small supply networks on the level of municipalities shall be erected instead. The use of hydrogen in the traffic seems to be useful in utility vehicles (e.g. buses) because the vehicle construction is more suitable for a safe integration of the tank system than in case of a car. The regulation shall be extended for a broader use of hydrogen and contain minimum requirements for the equipment and design of each application in terms of safety technology. (orig./MM) [de

  18. High and rapid hydrogen release from thermolysis of ammonia borane near PEM fuel cell operating temperature

    Science.gov (United States)

    Varma, Arvind; Hwang, Hyun Tae; Al-Kukhun, Ahmad

    2016-11-15

    A system for generating and purifying hydrogen. To generate hydrogen, the system includes inlets configured to receive a hydrogen carrier and an inert insulator, a mixing chamber configured to combine the hydrogen carrier and the inert insulator, a heat exchanger configured to apply heat to the mixture of hydrogen carrier and the inert insulator, wherein the applied heat results in the generation of hydrogen from the hydrogen carrier, and an outlet configured to release the generated hydrogen. To purify hydrogen, the system includes a primary inlet to receive a starting material and an ammonia filtration subassembly, which may include an absorption column configured to absorb the ammonia into water for providing purified hydrogen at a first purity level. The ammonia filtration subassembly may also include an adsorbent member configured to adsorb ammonia from the starting material into an adsorbent for providing purified hydrogen at a second purity level.

  19. US work on technical and economic aspects of electrolytic, thermochemical, and hybrid processes for hydrogen production at temperatures below 550 deg. C

    International Nuclear Information System (INIS)

    Petri, M.C.; Yyldyz, B.; Klickman, A.E.

    2006-01-01

    Hydrogen demand is increasing, but there are few options for affordable hydrogen production free of greenhouse gas emissions. Nuclear power is one of the most promising options. Most research is focused on high-temperature electrolytic and thermochemical processes for nuclear-generated hydrogen, but it will be many years before very high temperature reactors become commercially available. For light water reactors or supercritical reactors, low-temperature water electrolysis is a currently available technology for hydrogen production. Higher efficiencies may be gained through thermo-electrochemical hydrogen production cycles, but there are only a limited number that have heat requirements consistent with the lower temperatures of light-water reactor technology. Indeed, active research is ongoing for only three such cycles in the USA. Reductions in electricity and system costs would be needed (or the imposition of a carbon tax) for low-temperature water electrolysis to compete with today's costs for steam methane reformation. The interactions between hydrogen and electricity markets and hydrogen and electricity producers are complex and will evolve as the markets evolve. (author)

  20. Internal dosimetry of tritiated hydrogen gas

    International Nuclear Information System (INIS)

    Peterman, B.F.; Johnson, J.R.; Dunford, D.W.; McElroy, R.G.C.

    1985-02-01

    This document is a report on experiments to quantify the doses that may occur from the tritium gas that is converted 'in vivo' to tritiated water following the exposure to tritiated hydrogen gas contaminated air. This report also includes theoretical evaluation of the radiological hazards from the uptake through skin of tritium from tritiated hydrogen adsorbed on surfaces

  1. Iodine removal adsorbent histories, aging and regeneration

    International Nuclear Information System (INIS)

    Hunt, J.R.; Rankovic, L.; Lubbers, R.; Kovach, J.L.

    1976-01-01

    The experience of efficiency changes with life under various test conditions is described. The adsorbents were periodically removed from both standby and continuously operating systems and tested under various test methods for residual iodine adsorption efficiency. Adsorbent from several conventional ''sampler'' cartridges versus the bulk adsorbent was also tested showing deficiency in the use of cartridge type sampling. Currently required test conditions were found inadequate to follow the aging of the adsorbent because pre-equilibration of the sample acts as a regenerant and the sample is not tested in the ''as is'' condition. The most stringent test was found to be the ambient temperature, high humidity test to follow the aging of the adsorbent. Several methods were evaluated to regenerate used adsorbents; of these high temperature steaming and partial reimpregnation were found to produce adsorbents with near identical properties of freshly prepared adsorbents

  2. Hydrogen energy systems studies

    Energy Technology Data Exchange (ETDEWEB)

    Ogden, J.M.; Steinbugler, M.; Dennis, E. [Princeton Univ., NJ (United States)] [and others

    1995-09-01

    For several years, researchers at Princeton University`s Center for Energy and Environmental Studies have carried out technical and economic assessments of hydrogen energy systems. Initially, we focussed on the long term potential of renewable hydrogen. More recently we have explored how a transition to renewable hydrogen might begin. The goal of our current work is to identify promising strategies leading from near term hydrogen markets and technologies toward eventual large scale use of renewable hydrogen as an energy carrier. Our approach has been to assess the entire hydrogen energy system from production through end-use considering technical performance, economics, infrastructure and environmental issues. This work is part of the systems analysis activity of the DOE Hydrogen Program. In this paper we first summarize the results of three tasks which were completed during the past year under NREL Contract No. XR-11265-2: in Task 1, we carried out assessments of near term options for supplying hydrogen transportation fuel from natural gas; in Task 2, we assessed the feasibility of using the existing natural gas system with hydrogen and hydrogen blends; and in Task 3, we carried out a study of PEM fuel cells for residential cogeneration applications, a market which might have less stringent cost requirements than transportation. We then give preliminary results for two other tasks which are ongoing under DOE Contract No. DE-FG04-94AL85803: In Task 1 we are assessing the technical options for low cost small scale production of hydrogen from natural gas, considering (a) steam reforming, (b) partial oxidation and (c) autothermal reforming, and in Task 2 we are assessing potential markets for hydrogen in Southern California.

  3. Topological features of engineered arrays of adsorbates in honeycomb lattices

    Energy Technology Data Exchange (ETDEWEB)

    Gonzalez-Arraga, Luis A., E-mail: ludovici83@gmail.com [IMDEA Nanociencia, Calle de Faraday, 9, Cantoblanco, 28049 Madrid (Spain); Lado, J.L. [International Iberian Nanotechnology Laboratory (INL), Av. Mestre Jose Veiga, 4715-330 Braga (Portugal); Guinea, Francisco [IMDEA Nanociencia, Calle de Faraday, 9, Cantoblanco, 28049 Madrid (Spain); School of Physics and Astronomy, University of Manchester, Oxford Road, Manchester M13 9PL (United Kingdom)

    2016-09-01

    Hydrogen adatoms are one of the most the promising proposals for the functionalization of graphene. The adatoms induce narrow resonances near the Dirac energy, which lead to the formation of magnetic moments. Furthermore, they also create local lattice distortions which enhance the spin–orbit coupling. The combination of magnetism and spin–orbit coupling allows for a rich variety of phases, some of which have non-trivial topological features. We analyze the interplay between magnetism and spin–orbit coupling in ordered arrays of adsorbates on honeycomb lattice monolayers, and classify the different phases that may arise. We extend our model to consider arrays of adsorbates in graphene-like crystals with stronger intrinsic spin–orbit couplings. We also consider a regime away from half-filling in which the Fermi level is at the bottom of the conduction band, we find a Berry curvature distribution corresponding to a Valley–Hall effect.

  4. Supercritical fluid regeneration of adsorbents

    Science.gov (United States)

    Defilippi, R. P.; Robey, R. J.

    1983-05-01

    The results of a program to perform studies supercritical (fluid) carbon dioxide (SCF CO2) regeneration of adsorbents, using samples of industrial wastewaters from manufacturing pesticides and synthetic solution, and to estimate the economics of the specific wastewater treatment regenerations, based on test data are given. Processing costs for regenerating granular activated carbon GAC) for treating industrial wastewaters depend on stream properties and regeneration throughput.

  5. Bimetallic promotion of cooperative hydrogen transfer and heteroatom removal in coal liquefaction. Final technical report, September 1, 1988--December 31, 1991

    Energy Technology Data Exchange (ETDEWEB)

    Eisch, J.J.

    1992-04-07

    The ultimate objective of this research has been to uncover novel reagents and experimental conditions for heteroatom removal and hydrogen transfer processes, which would be applicable to the liquefaction of coal under low-severity conditions. To this end, one phase of this research has investigated the cleavage of carbon-heteroatom bonds involving sulfur, oxygen, nitrogen and halogen by subvalent transition-metal complexes. A second phase of the study has assessed the capability of the same transition-metal complexes or of organoaluminum Lewis acids to catalyze the cleavage of carbon-hydrogen bonds in aromatics and hence to promote hydrogen shuttling. Finally, a third phase of our work has uncovered a remarkable synergistic effect of combinations of transition metals with organoaluminum Lewis acids on hydrogen shuttling between aromatics and hydroaromatics. (VC)

  6. Low alloy steels that minimize the hydrogen-carbide reaction. Final technical report, October 1, 1978-September 30, 1979. Part I

    Energy Technology Data Exchange (ETDEWEB)

    Kar, R. J.; Parker, E. R.; Zackay, V. F.

    1979-01-01

    This report presents results obtained during the first year of a research program to investigate important metallurgical parameters that control the reactions of hydrogen with carbides in steels. Preliminary work included a detailed literature review of th phenomenon of decarburization and methane bubble formation in steels and a suitable experimental technique for investigating hydrogen attack in laboratory conditions was established. Detailed microstructural-mechanical property evaluations were carried out on two series of alloys; the first was based on a plain carbon steel to which binary and ternary alloy additions were made to vary the carbide structure and morphology and assess these effects on the observed hydrogen attack resistance. The second group of steels consisted of commercial Mn-Mo-Ni (A 533 B) and Cr-Mo (A 542 type) steels and their alloy modifications, with a view towards developing steels with improved hydrogen attack resistance.

  7. Borazine-boron nitride hybrid hydrogen storage system

    Science.gov (United States)

    Narula, Chaitanya K [Knoxville, TN; Simonson, J Michael [Knoxville, TN; Maya, Leon [Knoxville, TN; Paine, Robert T [Albuquerque, NM

    2008-04-22

    A hybrid hydrogen storage composition includes a first phase and a second phase adsorbed on the first phase, the first phase including BN for storing hydrogen by physisorption and the second phase including a borazane-borazine system for storing hydrogen in combined form as a hydride.

  8. Hydrogen Storage using Physisorption : Modified Carbon Nanofibers and Related Materials

    NARCIS (Netherlands)

    Nijkamp, Marije Gessien

    2002-01-01

    This thesis describes our research on adsorbent systems for hydrogen storage for small scale, mobile application. Hydrogen storage is a key element in the change-over from the less efficient and polluting internal combustion engine to the pollution-free operating hydrogen fuel cell. In general,

  9. Catalytic isotope exchange reaction between deuterium gas and water pre-adsorbed on platinum/alumina

    International Nuclear Information System (INIS)

    Iida, Itsuo; Kato, Junko; Tamaru, Kenzi.

    1976-01-01

    The catalytic isotope exchange reaction between deuterium gas and the water pre-adsorbed on Pt/Al 2 O 3 was studied. At reaction temperatures above 273 K, the exchange rate was proportional to the deuterium pressure and independent of the amount of adsorbed water, which suggests that the rate determining step is the supply of deuterium from the gas phase. Its apparent activation energy was 38 kJ mol -1 . Below freezing point of water, the kinetic behaviour was different from that above freezing point. At higher deuterium pressures the rate dropped abruptly at 273 K. Below the temperature the apparent activation energy was 54 kJ mol -1 and the exchange rate depended not on the deuterium pressure but on the amount of the pre-adsorbed water. At lower pressures, however, the kinetic behaviour was the same as the above 273 K, till the rate of the supply of deuterium from the gas phase exceeded the supply of hydrogen from adsorbed water to platinum surface. These results suggest that below 273 K the supply of hydrogen is markedly retarded, the state of the adsorbed water differing from that above 273 K. It was also demonstrated that when the adsorbed water is in the state of capillary condensation, the exchange rate becomes very small. (auth.)

  10. Hydrogen storage by adsorption on activated carbon: investigation of the thermal effects during the charging process; Stockage de l'hydrogene par adsorption sur charbon actif: etude des effets thermiques lors de la charge dynamique d'un reservoir a lit fixe adsorbant

    Energy Technology Data Exchange (ETDEWEB)

    Hermosilla-Lara, G

    2007-02-15

    This work presents an experimental and numerical investigation of the thermal effects occurring during the charge of adsorbent fixed bed tank. The influence of these thermal effects, which result from the exothermal character of the adsorption process and the pressure forces work, on the storage capacity is specially analysed. An experimental setup allowing the dynamic measurements of the temperature and pressure profiles has been used. Then the numerical protocol with the Fluent software, has been validated by comparison of the simulated pressure, flow rate and temperature fields in the tank with the results obtained from an experimental investigation carried out the dynamic storage. Several predictive simulations have been carried out in order to study the effect of the boundary conditions, as the wall temperature or effective thermal conductivity of the porous bed, on the storage capacity of the reservoir. We searched the optimal geometry of an interbed thermal dissipator for a given industrial tank. To do this we made vary the H/L ratio, which represents the ratio of the height of an elementary stage and the total length of the tank. We could determine an optimal geometry which corresponds to the value 1/3 of the ratio H/L. From this optimum we studied the effect of five additional cooling tubes on the tank storage capacity. The stored mass is 15 % higher than that obtained without these tubes. (author)

  11. Inelastic neutron scattering of H2 adsorbed in HKUST-1

    International Nuclear Information System (INIS)

    Liu, Y.; Brown, C.M.; Neumann, D.A.; Peterson, V.K.; Kepert, C.J.

    2007-01-01

    A series of inelastic neutron scattering (INS) investigations of hydrogen adsorbed in activated HKUST-1 (Cu 3 (1,3,5-benzenetricarboxylate) 2 ) result in INS spectra with rich features, even at very low loading ( 2 :Cu). The distinct inelastic features in the spectra show that there are three binding sites that are progressively populated when the H 2 loading is less than 2.0 H 2 :Cu, which is consistent with the result obtained from previous neutron powder diffraction experiments. The temperature dependence of the INS spectra reveals the relative binding enthalpies for H 2 at each site

  12. Hydrogen, Fuel Cells & Infrastructure Technologies Program

    Energy Technology Data Exchange (ETDEWEB)

    2005-03-01

    This plan details the goals, objectives, technical targets, tasks and schedule for EERE's contribution to the DOE Hydrogen Program. Similar detailed plans exist for the other DOE offices that make up the Hydrogen Program.

  13. Equilibrium and heat of adsorption of diethyl phthalate on heterogeneous adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Zhang, W.M.; Xu, Z.W.; Pan, B.C.; Hong, C.H.; Jia, K.; Jiang, P.J.; Zhang, Q.J.; Pan, B.J. [Nanjing University, Nanjing (China)

    2008-09-15

    Removal of phthalate esters from water has been of considerable concern recently. In the present study, the adsorptive removal performance of diethyl phthalate (DEP) from water was investigated with the aminated polystyrene resin (NDA-101) and oxidized polystyrene resin (NDA-702). In addition, the commercial homogeneous polystyrene resin (XAD-4) and acrylic ester resin (Amberlite XAD-7) as well as coal-based granular activated carbon (AC-750) were chosen for comparison. The corresponding equilibrium isotherms are well described by the Freundlich equation and the adsorption capacities for DEP followed the order NDA-702 > NDA-101 > AC-750 > XAD-4 > XAD-7. Analysis of adsorption mechanisms suggested that these adsorbents spontaneously adsorb DEP molecules driven mainly by enthalpy change, and the adsorption process was derived by multiple adsorbent-adsorbate interactions such as hydrogen bonding, {pi}-{pi} stacking, and micropore filling. The information related to the adsorbent surface heterogeneity and the adsorbate-adsorbate interaction was obtained by Do's model. All the results indicate that heterogeneous resins NDA-702 and NDA-101 have excellent potential as an adsorption material for the removal of DEP from the contaminated water.

  14. A novel fiber-based adsorbent technology

    Energy Technology Data Exchange (ETDEWEB)

    Reynolds, T.A. [Chemica Technologies, Inc., Bend, OR (United States)

    1997-10-01

    In this Phase I Small Business Innovation Research program, Chemica Technologies, Inc. is developing an economical, robust, fiber-based adsorbent technology for removal of heavy metals from contaminated water. The key innovation is the development of regenerable adsorbent fibers and adsorbent fiber cloths that have high capacity and selectivity for heavy metals and are chemically robust. The process has the potential for widespread use at DOE facilities, mining operations, and the chemical process industry.

  15. Hydrogen, energy of the future?

    International Nuclear Information System (INIS)

    Alleau, Th.

    2007-01-01

    A cheap, non-polluting energy with no greenhouse gas emissions and unlimited resources? This is towards this fantastic future that this book brings us, analyzing the complex but promising question of hydrogen. The scientific and technical aspects of production, transport, storage and distribution raised by hydrogen are thoroughly reviewed. Content: I) Energy, which solutions?: 1 - hydrogen, a future; 2 - hydrogen, a foreseeable solution?; II) Hydrogen, an energy vector: 3 - characteristics of hydrogen (physical data, quality and drawbacks); 4 - hydrogen production (from fossil fuels, from water, from biomass, bio-hydrogen generation); 5 - transport, storage and distribution of hydrogen; 6 - hydrogen cost (production, storage, transport and distribution costs); III) Fuel cells and ITER, utopias?: 7 - molecular hydrogen uses (thermal engines and fuel cells); 8 - hydrogen and fusion (hydrogen isotopes, thermonuclear reaction, ITER project, fusion and wastes); IV) Hydrogen acceptability: 9 - risk acceptability; 10 - standards and regulations; 11 - national, European and international policies about hydrogen; 12 - big demonstration projects in France and in the rest of the world; conclusion. (J.S.)

  16. Method of removing hydrogen sulphide from hot gas mixtures

    Energy Technology Data Exchange (ETDEWEB)

    Furimsky, E.; Yumura, M.

    1987-12-22

    Hydrogen sulphide can be removed from hot gas mixtures by contacting the hot gas mixture at temperatures in the range of 500-900/sup 0/C with an adsorbent consisting of managanese nodules. The nodules may contain additional calcium cations. In sulphided form, the nodules are catalytically active for hydrogen sulphide decomposition to produce hydrogen. Regeneration of the adsorbent can be accomplished by roasting in an oxidizing atmosphere. The nodules can be used to treat gaseous mixtures containing up to 20% hydrogen sulfide, for example, gases produced during pyrolysis, cracking, coking, and hydrotreating processes. Experiments using the processes described in this patent are also outlined. 6 tabs.

  17. Neutron scattering from adsorbed species

    International Nuclear Information System (INIS)

    Shuwang An

    1998-01-01

    Neutron reflection has been used to investigate the structure of layers of water-soluble diblock copolymers poly(2-(dimethylamino)ethyl methacrylate-block-methyl methacrylate (poly(DMAEMA-b-MMA)) (70 mol% DMAEMA, M n = 10k, 80 mol% DMAEMA, M n = 10k, and 70 mol% DMAEMA, M n = 20k) adsorbed at the air-liquid and solid-liquid interfaces. The surface tension behaviour of these copolymers at the air-liquid interface has also been investigated. The study of the structure of layers of poly(DMAEMA-b-MMA) adsorbed at the air-water interface forms the main part of the thesis. The surface structure, the effects of pH and ionic strength, and the effects of composition and molecular weight of the copolymers have been studied systematically. For the 70%-10k copolymer at pH 7.5, the adsorption isotherm shows that there is a surface phase transition. The concentration of copolymer at which the phase transition occurs is close to that at which micellar aggregation in the bulk solution also occurs. At low concentrations (below the CMC), the two blocks of the copolymer are approximately uniformly distributed in the direction normal to the interface and the layer is partially immersed in water. At high concentrations (above the CMC), the adsorbed layer has a cross-sectional structure resembling that expected for a micelle with the majority of the MMA blocks forming the core. The outer layers, comprising predominantly DMAEMA blocks, are not equivalent, being more highly extended on the aqueous side of the interface. The effects of pH and added electrolyte on the structure of layers of the 70%-10k copolymer show that the layered structure is promoted by any changes in the bulk solution that enhance the surface coverage but is inhibited by an increase in the fractional charge on the polyelectrolyte part of the copolymer. The effect of lowering the pH is to increase the positive charge on the weak polyelectrolyte block. Addition of electrolyte generally enhances the amount adsorbed and

  18. Filter-adsorber aging assessment

    Energy Technology Data Exchange (ETDEWEB)

    Winegardner, W.K. [Pacific Northwest Laboratory, Richland, WA (United States)

    1995-02-01

    An aging assessment of high-efficiency particulate (HEPA) air filters and activated carbon gas adsorption units was performed by the Pacific Northwest Laboratory as part of the U.S. Nuclear Regulatory Commission`s (USNRC) Nuclear Plant Aging Research (NPAR) Program. This evaluation of the general process in which characteristics of these two components gradually change with time or use included the compilation of information concerning failure experience, stressors, aging mechanisms and effects, and inspection, surveillance, and monitoring methods (ISMM). Stressors, the agents or stimuli that can produce aging degradation, include heat, radiation, volatile contaminants, and even normal concentrations of aerosol particles and gasses. In an experimental evaluation of degradation in terms of the tensile breaking strength of aged filter media specimens, over forty percent of the samples did not meet specifications for new material. Chemical and physical reactions can gradually embrittle sealants and gaskets as well as filter media. Mechanisms that can lead to impaired adsorber performance are associated with the loss of potentially available active sites as a result of the exposure of the carbon to airborne moisture or volatile organic compounds. Inspection, surveillance, and monitoring methods have been established to observe filter pressure drop buildup, check HEPA filters and adsorbers for bypass, and determine the retention effectiveness of aged carbon. These evaluations of installed filters do not reveal degradation in terms of reduced media strength but that under normal conditions aged media can continue to effectively retain particles. However, this degradation may be important when considering the likelihood of moisture, steam, and higher particle loadings during severe accidents and the fact it is probable that the filters have been in use for an extended period.

  19. Catalase-like activity studies of the manganese(II) adsorbed zeolites

    Science.gov (United States)

    Ćiçek, Ekrem; Dede, Bülent

    2013-12-01

    Preparation of manganese(II) adsorbed on zeolite 3A, 4A, 5A. AW-300, ammonium Y zeolite, organophilic, molecular sieve and catalase-like enzyme activity of manganese(II) adsorbed zeolites are reported herein. Firstly zeolites are activated at 873 K for two hours before contact manganese(II) ions. In order to observe amount of adsorption, filtration process applied for the solution. The pure zeolites and manganese(II) adsorbed zeolites were analysed by FT-IR. As a result according to the FT-IR spectra, the incorporation of manganese(II) cation into the zeolite structure causes changes in the spectra. These changes are expected particularly in the pseudolattice bands connected with the presence of alumino and silicooxygen tetrahedral rings in the zeolite structure. Furthermore, the catalytic activities of the Mn(II) adsorbed zeolites for the disproportionation of hydrogen peroxide were investigated in the presence of imidazole. The Mn(II) adsorbed zeolites display efficiency in the disproportion reactions of hydrogen peroxide, producing water and dioxygen in catalase-like activity.

  20. Hydrogen as automotive fuel

    International Nuclear Information System (INIS)

    Dini, D.; Ciancia, A.; Pede, G.; Sglavo, V.; ENEA, Rome

    1992-01-01

    An assessment of the technical/economic feasibility of the use of hydrogen as an automotive fuel is made based on analyses of the following: the chemical- physical properties of hydrogen in relation to its use in internal combustion engines; the modifications necessary to adapt internal combustion engines to hydrogen use; hydrogen fuel injection systems - with water vapour injection, cryogenic injection, and the low or high pressure injection of hydrogen directly into the combustion chamber; the current commercialization status of hydrogen automotive fuels; energy efficiency ratings; environmental impacts; in-vehicle storage systems - involving the use of hydrides, high pressure systems and liquid hydrogen storage systems; performance in terms of pay-load ratio; autonomous operation; and operating costs. The paper concludes that, considering current costs for hydrogen fuel production, distribution and use, at present, the employment of hydrogen fuelled vehicles is feasible only in highly polluted urban environments where the innovative vehicle's air pollution abatement characteristics would justify its high operating costs as compared with those of conventional automotive alternatives

  1. Complete braided adsorbent for marine testing to demonstrate 3g-U/kg-adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Janke, Chris [ORNL; Yatsandra, Oyola [ORNL; Mayes, Richard [ORNL; none,; Gill, Gary [PNNL; Li-Jung, Kuo [PNNL; Wood, Jordana [PNNL; Sadananda, Das [ORNL

    2014-04-30

    ORNL has manufactured four braided adsorbents that successfully demonstrated uranium adsorption capacities ranging from 3.0-3.6 g-U/kg-adsorbent in marine testing at PNNL. Four new braided and leno woven fabric adsorbents have also been prepared by ORNL and are currently undergoing marine testing at PNNL.

  2. Thermodynamics of gas adsorption on solid adsorbents

    International Nuclear Information System (INIS)

    Budrugeac, P.

    1979-01-01

    Starting with several hypotheses about the adsorbtion system and the adsorption phenomenon, a thermodynamic treatment of gas adsorption on solid adsorbants is presented. The relationships for determination from isotherms and calorimetric data of thermodynamic functions are derived. The problem of the phase changes in adsorbed layer is discussed. (author)

  3. Benzene adsorption and hydrogenation on Pd-Ru alloy by pulse chromatography

    International Nuclear Information System (INIS)

    Dobrokhotov, V.G.; Pavlova, L.F.; Gryaznov, V.M.

    1983-01-01

    Pulse chromatography has been applied to investigate benzene adsorption and hydrogenation on the Walls of a capillary of the Pd-6% Ru alloy at different hydrogen contents in the alloy and various methods of hydrogen supply: as a mixture with benzene vapors or by diffusion through the walls of the capillary. It is stated that reversible adsorption of benzene vapors on the Pd-6% Ru alloy at 303 K under the conditions of the β-phase existence in the alloy-hydrogen system does not change whereas in the region of the α-phase existence it slightly increases with a growth of hydrogen pressure. Strongly adsorbed benzene occupies approximately 7% of the surface. Only strongly adsorbed benzene is hydrogenated on the α-phase of the alloy-hydrogen system. Hydrogen supply to the hydrogenation zone by diffusion throUgh the alloy results in supersaturation of the surface active in the reaction of benzene hydrogenation with a chemisorbed hydrogen form

  4. Controlling Hydrogenation of Graphene on Ir(111)

    DEFF Research Database (Denmark)

    Balog, Richard; Andersen, Mie; Jørgensen, Bjarke

    2013-01-01

    Combined fast X-ray photoelectron spectroscopy and density functional theory calculations reveal the presence of two types of hydrogen adsorbate structures at the graphene/ Ir(111) interface, namely, graphane-like islands and hydrogen dimer structures. While the former give rise to a periodic...... pattern, dimers tend to destroy the periodicity. Our data reveal distinctive growth rates and stability of both types of structures, thereby allowing one to obtain well-defined patterns of hydrogen clusters. The ability to control and manipulate the formation and size of hydrogen structures on graphene...

  5. Hydrogen Filling Station

    Energy Technology Data Exchange (ETDEWEB)

    Boehm, Robert F; Sabacky, Bruce; Anderson II, Everett B; Haberman, David; Al-Hassin, Mowafak; He, Xiaoming; Morriseau, Brian

    2010-02-24

    future. Project partners also conducted a workshop on hydrogen safety and permitting. This provided an opportunity for the various permitting agencies and end users to gather to share experiences and knowledge. As a result of this workshop, the permitting process for the hydrogen filling station on the Las Vegas Valley Water District’s land was done more efficiently and those who would be responsible for the operation were better educated on the safety and reliability of hydrogen production and storage. The lessons learned in permitting the filling station and conducting this workshop provided a basis for future hydrogen projects in the region. Continuing efforts to increase the working pressure of electrolysis and efficiency have been pursued. Research was also performed on improving the cost, efficiency and durability of Proton Exchange Membrane (PEM) hydrogen technology. Research elements focused upon PEM membranes, electrodes/catalysts, membrane-electrode assemblies, seals, bipolar plates, utilization of renewable power, reliability issues, scale, and advanced conversion topics. Additionally, direct solar-to-hydrogen conversion research to demonstrate stable and efficient photoelectrochemistry (PEC) hydrogen production systems based on a number of optional concepts was performed. Candidate PEC concepts included technical obstacles such as inefficient photocatalysis, inadequate photocurrent due to non-optimal material band gap energies, rapid electron-hole recombination, reduced hole mobility and diminished operational lifetimes of surface materials exposed to electrolytes. Project Objective 1: Design, build, operate hydrogen filling station Project Objective 2: Perform research and development for utilizing solar technologies on the hydrogen filling station and convert two utility vehicles for use by the station operators Project Objective 3: Increase capacity of hydrogen filling station; add additional vehicle; conduct safety workshop; develop a roadmap for

  6. Cryogenic adsorption of low-concentration hydrogen on charcoal, 5A molecular sieve, sodalite, ZSM-5 and Wessalith DAY

    International Nuclear Information System (INIS)

    Willms, R.S.

    1993-01-01

    The separation of low-concentration hydrogen isotopes from helium is a processing step that is required for ceramic lithium breeding blanket processing. Cryogenic adsorption is one method of effecting this separation. In this study live adsorbents were considered for this purpose: charcoal, 5A molecular sieve, UOP S-115, ZSM-5 and Wessalith DAY. The first two adsorbents exhibit good equilibrium loadings and are shown to be quite effective at adsorbing low-concentration hydrogen isotopes. The latter three adsorbents display considerably lower equilibrium loadings. This study concludes that by using either charcoal or 5A molecular sieve, cryogenic adsorption would be an effective means of separating hydrogen isotopes from helium

  7. Analysis of Adsorbate-Adsorbate and Adsorbate-Adsorbent Interactions to Decode Isosteric Heats of Gas Adsorption.

    Science.gov (United States)

    Madani, S Hadi; Sedghi, Saeid; Biggs, Mark J; Pendleton, Phillip

    2015-12-21

    A qualitative interpretation is proposed to interpret isosteric heats of adsorption by considering contributions from three general classes of interaction energy: fluid-fluid heat, fluid-solid heat, and fluid-high-energy site (HES) heat. Multiple temperature adsorption isotherms are defined for nitrogen, T=(75, 77, 79) K, argon at T=(85, 87, 89) K, and for water and methanol at T=(278, 288, 298) K on a well-characterized polymer-based, activated carbon. Nitrogen and argon are subjected to isosteric heat analyses; their zero filling isosteric heats of adsorption are consistent with slit-pore, adsorption energy enhancement modelling. Water adsorbs entirely via specific interactions, offering decreasing isosteric heat at low pore filling followed by a constant heat slightly in excess of water condensation enthalpy, demonstrating the effects of micropores. Methanol offers both specific adsorption via the alcohol group and non-specific interactions via its methyl group; the isosteric heat increases at low pore filling, indicating the predominance of non-specific interactions. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. Inorganic chemically active adsorbents (ICAAs)

    Energy Technology Data Exchange (ETDEWEB)

    Ally, M.R. [Oak Ridge National Lab., TN (United States); Tavlarides, L.

    1997-10-01

    Oak Ridge National Laboratory (ORNL) researchers are developing a technology that combines metal chelation extraction technology and synthesis chemistry. They begin with a ceramic substrate such as alumina, titanium oxide or silica gel because they provide high surface area, high mechanical strength, and radiolytic stability. One preparation method involves silylation to hydrophobize the surface, followed by chemisorption of a suitable chelation agent using vapor deposition. Another route attaches newly designed chelating agents through covalent bonding by the use of coupling agents. These approaches provide stable and selective, inorganic chemically active adsorbents (ICAAs) tailored for removal of metals. The technology has the following advantages over ion exchange: (1) higher mechanical strength, (2) higher resistance to radiation fields, (3) higher selectivity for the desired metal ion, (4) no cation exchange, (5) reduced or no interference from accompanying anions, (6) faster kinetics, and (7) easy and selective regeneration. Target waste streams include metal-containing groundwater/process wastewater at ORNL`s Y-12 Plant (multiple metals), Savannah River Site (SRS), Rocky Flats (multiple metals), and Hanford; aqueous mixed wastes at Idaho National Engineering Laboratory (INEL); and scrubber water generated at SRS and INEL. Focus Areas that will benefit from this research include Mixed Waste, and Subsurface Contaminants.

  9. Process analysis and economics of biophotolysis of water. IEA technical report from the IEA Agreement on the Production and Utilization of Hydrogen

    Energy Technology Data Exchange (ETDEWEB)

    Benemann, J.R.

    1998-03-31

    This report is a preliminary cost analysis of the biophotolysis of water and was prepared as part of the work of Annex 10 of the IEA Hydrogen agreement. Biophotolysis is the conversion of water and solar energy to hydrogen and oxygen using microalgae. In laboratory experiments at low light intensities, algal photosynthesis and some biophotolysis reactions exhibit highlight conversion efficiencies that could be extrapolated to about 10% solar efficiencies if photosynthesis were to saturate at full sunlight intensities. The most promising approach to achieving the critical goal of high conversion efficiencies at full sunlight intensities, one that appears within the capabilities of modern biotechnology, is to genetically control the pigment content of algal cells such that the photosynthetic apparatus does not capture more photons than it can utilize. A two-stage indirect biophotolysis system was conceptualized and general design parameters extrapolated. The process comprises open ponds for the CO{sub 2}fixation stage, an algal concentration step, a dark adaptation and fermentation stage, and a closed tubular photobioreactor in which hydrogen production would take place. A preliminary cost analysis for a 200 hectare (ha) system, including 140 ha of open algal ponds and 14 ha of photobioreactors was carried out. The cost analysis was based on prior studies for algal mass cultures for fuels production and a conceptual analysis of a hypothetical photochemical processes, as well as the assumption that the photobioreactors would cost about $100/m(sup 2). Assuming a very favorable location, with 21 megajoules (MJ)/m{sup 2} total insolation, and a solar conversion efficiency of 10% based on CO{sub 2} fixation in the large algal ponds, an overall cost of $10/gigajoule (GJ) is projected. Of this, almost half is due to the photobioreactors, one fourth to the open pond system, and the remainder to the H{sub 2} handling and general support systems. It must be cautioned that

  10. Hydrogen sensor

    Science.gov (United States)

    Duan, Yixiang; Jia, Quanxi; Cao, Wenqing

    2010-11-23

    A hydrogen sensor for detecting/quantitating hydrogen and hydrogen isotopes includes a sampling line and a microplasma generator that excites hydrogen from a gas sample and produces light emission from excited hydrogen. A power supply provides power to the microplasma generator, and a spectrometer generates an emission spectrum from the light emission. A programmable computer is adapted for determining whether or not the gas sample includes hydrogen, and for quantitating the amount of hydrogen and/or hydrogen isotopes are present in the gas sample.

  11. Hydrogen purification by periodic adsorption

    Energy Technology Data Exchange (ETDEWEB)

    Barg, Christian; Secchi, Argimiro R.; Trierweiler, Jorge O. [Rio Grande do Sul Univ., Porto Alegre, RS (Brazil). Dept. de Engenharia Quimica]. E-mail: cbarg@enq.ufrgs.br; arge@enq.ufrgs.br; jorge@enq.ufrgs.br

    2000-07-01

    The periodic adsorption processes have been widely used for industrial applications, mainly because it spends less energy than the usual gas separation processes, like the cryogenic distillation. The largest commercial application of periodic adsorption processes is the pressure swing adsorption (PSA) applied to hydrogen purification. Although its wide use in the chemical and petrochemical industry, there are no reports in the open literature about complete modeling studies of a complex commercial unit, with multiple adsorbents and multiple beds and several feed components. This study has as objective the modeling, optimization and dynamical analysis of an industrial PSA unit for hydrogen purification. (author)

  12. Hydrogen system (hydrogen fuels feasibility)

    International Nuclear Information System (INIS)

    Guarna, S.

    1991-07-01

    This feasibility study on the production and use of hydrogen fuels for industry and domestic purposes includes the following aspects: physical and chemical properties of hydrogen; production methods steam reforming of natural gas, hydrolysis of water; liquid and gaseous hydrogen transportation and storage (hydrogen-hydride technology); environmental impacts, safety and economics of hydrogen fuel cells for power generation and hydrogen automotive fuels; relevant international research programs

  13. Alkali metal adsorbate sputtering by molecular impact

    International Nuclear Information System (INIS)

    Moran, J.P.; Wachman, H.Y.; Trilling, L.

    1974-01-01

    An exploratory study of the sputtering by a krypton molecular beam of rubidium adsorbed at low coverage on a tungsten substrate has been described in a previous paper. An extension of this work is reported now

  14. PERVAPORATION USING ADSORBENT-FILLED MEMBRANES

    Science.gov (United States)

    Membranes containing selective fillers, such as zeolites and activated carbon, can improve the separation by pervaporation. Applications of adsorbent-filled membranes in pervaporation have been demonstrated by a number of studies. These applications include removal of organic co...

  15. Chitin Adsorbents for Toxic Metals: A Review

    Directory of Open Access Journals (Sweden)

    Ioannis Anastopoulos

    2017-01-01

    Full Text Available Wastewater treatment is still a critical issue all over the world. Among examined methods for the decontamination of wastewaters, adsorption is a promising, cheap, environmentally friendly and efficient procedure. There are various types of adsorbents that have been used to remove different pollutants such as agricultural waste, compost, nanomaterials, algae, etc., Chitin (poly-β-(1,4-N-acetyl-d-glucosamine is the second most abundant natural biopolymer and it has attracted scientific attention as an inexpensive adsorbent for toxic metals. This review article provides information about the use of chitin as an adsorbent. A list of chitin adsorbents with maximum adsorption capacity and the best isotherm and kinetic fitting models are provided. Moreover, thermodynamic studies, regeneration studies, the mechanism of adsorption and the experimental conditions are also discussed in depth.

  16. Black Sprayable Molecular Adsorber Coating Project

    Data.gov (United States)

    National Aeronautics and Space Administration — The main objective of this technology project is to develop, optimize, and flight qualify a black version of the molecular adsorber coating and a conductive version...

  17. Dissolved Air Flotation of arsenic adsorbent particles

    Directory of Open Access Journals (Sweden)

    Mario Enrique Santander Muñoz

    2015-01-01

    Full Text Available The removal of arsenic from synthetic effluent was studied using the adsorbent particle flotation technique (APF and dissolved air flotation (DAF. A sample of an iron mineral was used as adsorbent particles of arsenic, ferric chloride as coagulant, cationic poly-acrylamide (NALCO 9808 as flocculants, and sodium oleate as collector. Adsorption studies to determine the pH influence, contact time, and adsorbent particles concentration on the adsorption of arsenic were carried out along with flotation studies to determine the removal efficiency of adsorbents particles. The results achieved indicate that the adsorption kinetic of arsenic is very rapid and that in range of pH’s from 2 to 7 the adsorption percentages remain constant. The equilibrium conditions were achieved in 60 minutes and about 95% of arsenic was adsorbed when used an adsorbent concentration of 2 g/L and pH 6.3. The maximum adsorption capacity of adsorbent particles was 4.96 mg/g. The mean free energy of adsorption (E was found to be 2.63 kJ/mol, which suggests physisorption. The results of the flotation studies demonstrated that when synthetic effluents with 8.9 mg/L of arsenic were treated under the following experimental conditions; 2 g/L of adsorbent particles, 120 mg/L of Fe(III, 2 mg/L of Nalco 9808, 20 mg/L of sodium oleate, and 40% of recycle ratio in the DAF, it was possible to reach 98% of arsenic removal and 6.3 NTU of residual turbidity in clarified synthetic effluent.

  18. Properties and selection criteria for adsorbents

    International Nuclear Information System (INIS)

    Wirth, H.

    1976-01-01

    The paper gives a survey of the most important industrial adsorbents and of their suitability for different purposes. With special consideration of activated carbon, the properties and characteristic data are discussed which are used for assessing adsorbents. These, among other things, are as follows: specific surface area, pore size distribution, adsorption isotherms, hydrophobic properties, catalytic properties, chemical resistance, heat resistance, particle size and hardness. (orig.) [de

  19. Protein purification using magnetic adsorbent particles

    DEFF Research Database (Denmark)

    Franzreb, M; Siemann-Herzberg, M.; Hobley, Timothy John

    2006-01-01

    The application of functionalised magnetic adsorbent particles in combination with magnetic separation techniques has received considerable attention in recent years. The magnetically responsive nature of such adsorbent particles permits their selective manipulation and separation in the presence...... separations are fast, gentle, scaleable, easily automated, can achieve separations that would be impossible or impractical to achieve by other techniques, and have demonstrated credibility in a wide range of disciplines, including minerals processing, wastewater treatment, molecular biology, cell sorting...

  20. Mesoporous Silica: A Suitable Adsorbent for Amines

    Directory of Open Access Journals (Sweden)

    Abdollahzadeh-Ghom Sara

    2009-01-01

    Full Text Available Abstract Mesoporous silica with KIT-6 structure was investigated as a preconcentrating material in chromatographic systems for ammonia and trimethylamine. Its adsorption capacity was compared to that of existing commercial materials, showing its increased adsorption power. In addition, KIT-6 mesoporous silica efficiently adsorbs both gases, while none of the employed commercial adsorbents did. This means that KIT-6 Mesoporous silica may be a good choice for integrated chromatography/gas sensing micro-devices.

  1. Correlations between electrochemical activity and heterogeneous catalysis for hydrogen dissociation on platinum

    Energy Technology Data Exchange (ETDEWEB)

    Ross, P N; Stonehart, P [Pratt and Whitney Aircraft, Middletown, Conn. (USA)

    1975-02-01

    Hydrogen-deuterium exchange rates on platinum surfaces have been compared to equivalent hydrogen molecule and adsorbed hydrogen atom electrochemical oxidation rates on the same surfaces. Over a temperature range of 293 to 360/sup 0/K the first order rate constants for H/sub 2/-D/sub 2/ exchange and hydrogen molecule electrochemical oxidation are the same, showing that the absorption-dissociation reaction (TAFEL, BONHOEFFER-FARKAS) is rate controlling. The rate of oxidation of the adsorbed hydrogen atom reaction involving electron transfer (VOLMER) is an order of magnitude larger.

  2. Hail hydrogen

    International Nuclear Information System (INIS)

    Hairston, D.

    1996-01-01

    After years of being scorned and maligned, hydrogen is finding favor in environmental and process applications. There is enormous demand for the industrial gas from petroleum refiners, who need in creasing amounts of hydrogen to remove sulfur and other contaminants from crude oil. In pulp and paper mills, hydrogen is turning up as hydrogen peroxide, displacing bleaching agents based on chlorine. Now, new technologies for making hydrogen have the industry abuzz. With better capabilities of being generated onsite at higher purity levels, recycled and reused, hydrogen is being prepped for a range of applications, from waste reduction to purification of Nylon 6 and hydrogenation of specialty chemicals. The paper discusses the strong market demand for hydrogen, easier routes being developed for hydrogen production, and the use of hydrogen in the future

  3. Hydrogen storage by physisorption on porous materials

    Energy Technology Data Exchange (ETDEWEB)

    Panella, B.

    2006-09-13

    A great challenge for commercializing hydrogen powered vehicles is on-board hydrogen storage using economic and secure systems. A possible solution is hydrogen storage in light-weight solid materials. Here three principle storage mechanisms can be distinguished: i) absorption of hydrogen in metals ii) formation of compounds with ionic character, like complex hydrides and iii) physisorption (or physical adsorption) of hydrogen molecules on porous materials. Physical adsorption exhibits several advantages over chemical hydrogen storage as for example the complete reversibility and the fast kinetics. Two classes of porous materials were investigated for physical hydrogen storage, i.e. different carbon nanostructures and crystalline metal-organic frameworks possessing extremely high specific surface area. Hydrogen adsorption isotherms were measured using a Sieverts' apparatus both at room temperature and at 77 K at pressures up to the saturation regime. Additionally, the adsorption sites of hydrogen in these porous materials were identified using thermal desorption spectroscopy extended to very low temperatures (down to 20 K). Furthermore, the adsorbed hydrogen phase was studied in various materials using Raman spectroscopy at different pressures and temperatures. The results show that the maximum hydrogen storage capacity of porous materials correlates linearly with the specific surface area and is independent of structure and composition. In addition the pore structure of the adsorbent plays an important role for hydrogen storage since the adsorption sites for H2 could be assigned to pores possessing different dimensions. Accordingly it was shown that small pores are necessary to reach high storage capacities already at low pressures. This new understanding may help to tailor and optimize new porous materials for hydrogen storage. (orig.)

  4. Hydrogen storage by physisorption on porous materials

    Energy Technology Data Exchange (ETDEWEB)

    Panella, B

    2006-09-13

    A great challenge for commercializing hydrogen powered vehicles is on-board hydrogen storage using economic and secure systems. A possible solution is hydrogen storage in light-weight solid materials. Here three principle storage mechanisms can be distinguished: i) absorption of hydrogen in metals ii) formation of compounds with ionic character, like complex hydrides and iii) physisorption (or physical adsorption) of hydrogen molecules on porous materials. Physical adsorption exhibits several advantages over chemical hydrogen storage as for example the complete reversibility and the fast kinetics. Two classes of porous materials were investigated for physical hydrogen storage, i.e. different carbon nanostructures and crystalline metal-organic frameworks possessing extremely high specific surface area. Hydrogen adsorption isotherms were measured using a Sieverts' apparatus both at room temperature and at 77 K at pressures up to the saturation regime. Additionally, the adsorption sites of hydrogen in these porous materials were identified using thermal desorption spectroscopy extended to very low temperatures (down to 20 K). Furthermore, the adsorbed hydrogen phase was studied in various materials using Raman spectroscopy at different pressures and temperatures. The results show that the maximum hydrogen storage capacity of porous materials correlates linearly with the specific surface area and is independent of structure and composition. In addition the pore structure of the adsorbent plays an important role for hydrogen storage since the adsorption sites for H2 could be assigned to pores possessing different dimensions. Accordingly it was shown that small pores are necessary to reach high storage capacities already at low pressures. This new understanding may help to tailor and optimize new porous materials for hydrogen storage. (orig.)

  5. The hydrogen highway

    International Nuclear Information System (INIS)

    Grigg, A.

    2004-01-01

    'Full text:' The Hydrogen Highway in British Columbia, Canada, is a coordinated, large-scale demonstration and deployment program aimed at accelerating the commercialization of hydrogen and fuel cell technologies and products. It will be a showcase for fuel cell vehicles, refuelling stations and stationary power systems leading up to the 2010 Olympic and Paralympic Winter Games in Whistler, BC. The Hydrogen Highway is designed to help address many of the challenges to commercialization identified in the Canadian Fuel Cell Commercialization Roadmap. The project will create an early adopter network of hydrogen and fuel cell microenvironments where technology developers and users can learn about the technical, economic, environmental and social impacts of products. The Hydrogen Highway will give the public and potential purchasers an opportunity to feel, touch and see the new technology, as well as provide the industry with a venue in which to develop industry standards and supply chains of materials and components. While demonstration and deployment programs are a recognized and necessary component in the process to commercialize hydrogen and fuel cell technologies, there is no handbook describing how it should be done. This paper will describe the history, objectives, project details and some of the challenges associated with establishing Canada's Hydrogen Highway. (author)

  6. The hydrogen highway

    Energy Technology Data Exchange (ETDEWEB)

    Grigg, A. [Fuel Cells Canada, Vancouver, British Columbia (Canada)

    2004-07-01

    'Full text:' The Hydrogen Highway in British Columbia, Canada, is a coordinated, large-scale demonstration and deployment program aimed at accelerating the commercialization of hydrogen and fuel cell technologies and products. It will be a showcase for fuel cell vehicles, refuelling stations and stationary power systems leading up to the 2010 Olympic and Paralympic Winter Games in Whistler, BC. The Hydrogen Highway is designed to help address many of the challenges to commercialization identified in the Canadian Fuel Cell Commercialization Roadmap. The project will create an early adopter network of hydrogen and fuel cell microenvironments where technology developers and users can learn about the technical, economic, environmental and social impacts of products. The Hydrogen Highway will give the public and potential purchasers an opportunity to feel, touch and see the new technology, as well as provide the industry with a venue in which to develop industry standards and supply chains of materials and components. While demonstration and deployment programs are a recognized and necessary component in the process to commercialize hydrogen and fuel cell technologies, there is no handbook describing how it should be done. This paper will describe the history, objectives, project details and some of the challenges associated with establishing Canada's Hydrogen Highway. (author)

  7. Noble gas separation from nuclear reactor effluents using selective adsorption with inorganic adsorbents

    International Nuclear Information System (INIS)

    Pence, D.T.; Paplawsky, W.J.

    1981-01-01

    A radioactive waste gas treatment system utilizing selective adsorption on inorganic adsorbents is described for application to PWRs. The system operates at near ambient pressure, does not require a hydrogen recombiner, has low radioactive gas inventories, and is cost competitive with existing treatment systems. The proposed technique is also applicable for recovery of noble gases from the containment building of a nuclear reactor after an accident. A system design for this application is also presented

  8. Commodity hydrogen from off-peak electricity

    Energy Technology Data Exchange (ETDEWEB)

    Darrow, K.; Biederman, N.; Konopka, A.

    1977-01-01

    This paper considers the use of off-peak electrical power as an energy source for the electrolytic production of hydrogen. The present industrial uses for hydrogen are examined to determine if hydrogen produced in this fashion would be competitive with the industry's onsite production or existing hydrogen prices. The paper presents a technical and economic feasibility analysis of the various components required and of the operation of the system as a whole including production, transmission, storage, and markets.

  9. Detection of hydrogen peroxide with graphyne

    Science.gov (United States)

    Majidi, R.; Karami, A. R.

    2013-12-01

    The effect of hydrogen peroxide on the electronic properties of graphyne has been investigated to explore the possibility of using graphyne based biosensor. We have used density functional theory to study the electronic properties of γ-graphyne in the presence of different number of hydrogen peroxide. The optimal adsorption position, orientation, and distance of hydrogen peroxide adsorbed on the graphyne sheet have been determined by calculating adsorption energy. It is found that γ-graphyne which is an intrinsic semiconductor becomes an n-type semiconductor due to the presence of hydrogen peroxide. The energy band gap of γ-graphyne is decreased by increasing the number of hydrogen peroxide. The results demonstrate that γ-graphyne is a promising candidate for biosensor application because of its electrical sensitivity to hydrogen peroxide.

  10. First-principles study of pollutant molecules absorbed on polymeric adsorbents using the vdW-DF2 functional

    Science.gov (United States)

    Zhu, Jinguo; Wang, Yapeng; Tian, Ting; Zhang, Qianfan

    2018-03-01

    Polymeric adsorbents have been attracting increasing attention because of their favorable structrual properties and effectiveness of solving small molecules contaminants. However, due to the absence of deep insight into the adsorption mechanism of polymeric adsorbents, researches on new polymeric adsorbents can only be carried out by repeated experiments and tests, which is extremely inefficient. Therefore, investigating the adsorption process of polymeric adsorbents, especially the mechanism of adsorbing various air pollutant molecules by materials modelling and simulation, is of great significance. Here in this work, we systematically studied the adsorption mechanism by first-principles computation with van der Waals interaction. It demonstrates that the adsorption between them was pure physisorption originating from the hydrogen bond and intermolecular forces consisting of Keesom force, Debye force and London dispersion force. The proportions of these forces varied according to different adsorption systems. The adsorption effects were determined by the polymers’ dipole moment and polarizability. The adsorption performance of some polymers with special structures was also investigated to explore their possibility as potential adsorbents. The results of our simulation can provide some guidance for developing new polymeric adsorbents with better performance.

  11. Novel Fiber-Based Adsorbent Technology; FINAL

    International Nuclear Information System (INIS)

    Nixon, P.G.; Tsukamoto, T.; Brose, D.J.

    2001-01-01

    The overall of this Department of Energy (DOE) Phase II SBIR program was to develop a new class of highly robust fiber-based adsorbents for recovery of heavy metals from aqueous waste-streams. The fiber-based adsorbents,when commercialized,will be used for clean up metals in aqueous waste-streams emanating from DOE facilities,industry,mining,and groundwater-cleanup operations.The amount of toxic waste released by these streams is of great significance.The U.S.Environment Protection Agency (EPA) reports that in 1990 alone,4.8 billion pounds of toxic chemicals were released into the environment.Of this waste,the metals-containing waste was the second largest contributor,representing 569 million pounds. This report presents the results of the Phase II program,which successfully synthesized noval fiber-based adsorbents for the removal of Group 12 metals(i.e.mercury),Group 14 metals (lead),and Group 10 metals(platinum and palladium) from contaminated groundwater and industrial waste streams.These fiber-based adsorbents are ideally suited for the recovery of metal ions from aqueous waste streams presently not treatable due to the degrading nature of corrosive chemicals or radioactive components in the feed stream. The adsorbents developed in this program rely on chemically resistant and robust carbon fibers and fabrics as supports for metal-ion selective ligands.These adsorbents demonstrate loading capacities and selectivities for metal ions exceeding those of conventional ion-exchange resins.The adsorbents were also used to construct filter modules that demonstrate minimal fouling,minimal compaction,chemical and physical robustness,and regeneration of metal loading capacity without loss of performance

  12. BIG hydrogen: hydrogen technology in the oil and gas sector

    International Nuclear Information System (INIS)

    2006-01-01

    The BIG Hydrogen workshop was held in Calgary, Alberta, Canada on February 13, 2006. About 60 representatives of industry, academia and government attended this one-day technical meeting on hydrogen production for the oil and gas industry. The following themes were identified from the presentations and discussion: the need to find a BIG hydrogen replacement for Steam Methane Reformer (SMR) because of uncertainty regarding cost and availability of natural gas, although given the maturity of SMR process (reliability, known capital cost) how high will H2 prices have to rise?; need for a national strategy to link the near-term and the longer-term hydrogen production requirements, which can take hydrogen from chemical feedstock to energy carrier; and in the near-term Canada should get involved in demonstrations and build expertise in large hydrogen systems including production and carbon capture and sequestration

  13. Hydrogen storage in graphite nanofibers

    Energy Technology Data Exchange (ETDEWEB)

    Park, C.; Tan, C.D.; Hidalgo, R.; Baker, R.T.K.; Rodriguez, N.M. [Northeastern Univ., Boston, MA (United States). Chemistry Dept.

    1998-08-01

    Graphite nanofibers (GNF) are a type of material that is produced by the decomposition of carbon containing gases over metal catalyst particles at temperatures around 600 C. These molecularly engineered structures consist of graphene sheets perfectly arranged in a parallel, perpendicular or at angle orientation with respect to the fiber axis. The most important feature of the material is that only edges are exposed. Such an arrangement imparts the material with unique properties for gas adsorption because the evenly separated layers constitute the most ordered set of nanopores that can accommodate an adsorbate in the most efficient manner. In addition, the non-rigid pore walls can also expand so as to accommodate hydrogen in a multilayer conformation. Of the many varieties of structures that can be produced the authors have discovered that when gram quantities of a selected number of GNF are exposed to hydrogen at pressures of {approximately} 2,000 psi, they are capable of adsorbing and storing up to 40 wt% of hydrogen. It is believed that a strong interaction is established between hydrogen and the delocalized p-electrons present in the graphite layers and therefore a new type of chemistry is occurring within these confined structures.

  14. Hydrogen detector

    International Nuclear Information System (INIS)

    Kumagaya, Hiromichi; Yoshida, Kazuo; Sanada, Kazuo; Chigira, Sadao.

    1994-01-01

    The present invention concerns a hydrogen detector for detecting water-sodium reaction. The hydrogen detector comprises a sensor portion having coiled optical fibers and detects hydrogen on the basis of the increase of light transmission loss upon hydrogen absorption. In the hydrogen detector, optical fibers are wound around and welded to the outer circumference of a quartz rod, as well as the thickness of the clad layer of the optical fiber is reduced by etching. With such procedures, size of the hydrogen detecting sensor portion can be decreased easily. Further, since it can be used at high temperature, diffusion rate is improved to shorten the detection time. (N.H.)

  15. Black molecular adsorber coatings for spaceflight applications

    Science.gov (United States)

    Abraham, Nithin S.; Hasegawa, Mark M.; Straka, Sharon A.

    2014-09-01

    The molecular adsorber coating is a new technology that was developed to mitigate the risk of on-orbit molecular contamination on spaceflight missions. The application of this coating would be ideal near highly sensitive, interior surfaces and instruments that are negatively impacted by outgassed molecules from materials, such as plastics, adhesives, lubricants, epoxies, and other similar compounds. This current, sprayable paint technology is comprised of inorganic white materials made from highly porous zeolite. In addition to good adhesion performance, thermal stability, and adsorptive capability, the molecular adsorber coating offers favorable thermal control characteristics. However, low reflectivity properties, which are typically offered by black thermal control coatings, are desired for some spaceflight applications. For example, black coatings are used on interior surfaces, in particular, on instrument baffles for optical stray light control. Similarly, they are also used within light paths between optical systems, such as telescopes, to absorb light. Recent efforts have been made to transform the white molecular adsorber coating into a black coating with similar adsorptive properties. This result is achieved by optimizing the current formulation with black pigments, while still maintaining its adsorption capability for outgassing control. Different binder to pigment ratios, coating thicknesses, and spray application techniques were explored to develop a black version of the molecular adsorber coating. During the development process, coating performance and adsorption characteristics were studied. The preliminary work performed on black molecular adsorber coatings thus far is very promising. Continued development and testing is necessary for its use on future contamination sensitive spaceflight missions.

  16. Process for producing zeolite adsorbent and process for treating radioactive liquid waste with the zeolite adsorbent

    International Nuclear Information System (INIS)

    Motojima, K.; Kawamura, F.

    1984-01-01

    Zeolite is contacted with an aqueous solution containing at least one of copper, nickel, cobalt, manganese and zinc salts, preferably copper and nickel salts, particularly preferably copper salt, in such a form as sulfate, nitrate, or chloride, thereby adsorbing the metal on the zeolite in its pores by ion exchange, then the zeolite is treated with a water-soluble ferrocyanide compound, for example, potassium ferrocyanide, thereby forming metal ferrocyanide on the zeolite in its pores. Then, the zeolite is subjected to ageing treatment, thereby producing a zeolite adsorbent impregnated with metal ferrocyanide in the pores of zeolite. The adsorbent can selectively recover cesium with a high percent cesium removal from a radioactive liquid waste containing at least radioactive cesium, for example, a radioactive liquid waste containing cesium and such coexisting ions as sodium, magnesium, calcium and carbonate ions at the same time at a high concentration. The zeolite adsorbent has a stable adsorbability for a prolonged time

  17. Method for modifying trigger level for adsorber regeneration

    Science.gov (United States)

    Ruth, Michael J.; Cunningham, Michael J.

    2010-05-25

    A method for modifying a NO.sub.x adsorber regeneration triggering variable. Engine operating conditions are monitored until the regeneration triggering variable is met. The adsorber is regenerated and the adsorbtion efficiency of the adsorber is subsequently determined. The regeneration triggering variable is modified to correspond with the decline in adsorber efficiency. The adsorber efficiency may be determined using an empirically predetermined set of values or by using a pair of oxygen sensors to determine the oxygen response delay across the sensors.

  18. Adsorbent catalytic nanoparticles and methods of using the same

    Energy Technology Data Exchange (ETDEWEB)

    Slowing, Igor Ivan; Kandel, Kapil

    2017-01-31

    The present invention provides an adsorbent catalytic nanoparticle including a mesoporous silica nanoparticle having at least one adsorbent functional group bound thereto. The adsorbent catalytic nanoparticle also includes at least one catalytic material. In various embodiments, the present invention provides methods of using and making the adsorbent catalytic nanoparticles. In some examples, the adsorbent catalytic nanoparticles can be used to selectively remove fatty acids from feedstocks for biodiesel, and to hydrotreat the separated fatty acids.

  19. Hydrogen-based electrochemical energy storage

    Science.gov (United States)

    Simpson, Lin Jay

    2013-08-06

    An energy storage device (100) providing high storage densities via hydrogen storage. The device (100) includes a counter electrode (110), a storage electrode (130), and an ion conducting membrane (120) positioned between the counter electrode (110) and the storage electrode (130). The counter electrode (110) is formed of one or more materials with an affinity for hydrogen and includes an exchange matrix for elements/materials selected from the non-noble materials that have an affinity for hydrogen. The storage electrode (130) is loaded with hydrogen such as atomic or mono-hydrogen that is adsorbed by a hydrogen storage material such that the hydrogen (132, 134) may be stored with low chemical bonding. The hydrogen storage material is typically formed of a lightweight material such as carbon or boron with a network of passage-ways or intercalants for storing and conducting mono-hydrogen, protons, or the like. The hydrogen storage material may store at least ten percent by weight hydrogen (132, 134) at ambient temperature and pressure.

  20. Hydrogen highway

    International Nuclear Information System (INIS)

    Anon

    2008-01-01

    The USA Administration would like to consider the US power generating industry as a basis ensuring both the full-scale production of hydrogen and the widespread use of the hydrogen related technological processes into the economy [ru

  1. Examining hydrogen transitions.

    Energy Technology Data Exchange (ETDEWEB)

    Plotkin, S. E.; Energy Systems

    2007-03-01

    This report describes the results of an effort to identify key analytic issues associated with modeling a transition to hydrogen as a fuel for light duty vehicles, and using insights gained from this effort to suggest ways to improve ongoing modeling efforts. The study reported on here examined multiple hydrogen scenarios reported in the literature, identified modeling issues associated with those scenario analyses, and examined three DOE-sponsored hydrogen transition models in the context of those modeling issues. The three hydrogen transition models are HyTrans (contractor: Oak Ridge National Laboratory), MARKAL/DOE* (Brookhaven National Laboratory), and NEMS-H2 (OnLocation, Inc). The goals of these models are (1) to help DOE improve its R&D effort by identifying key technology and other roadblocks to a transition and testing its technical program goals to determine whether they are likely to lead to the market success of hydrogen technologies, (2) to evaluate alternative policies to promote a transition, and (3) to estimate the costs and benefits of alternative pathways to hydrogen development.

  2. Noncatalytic hydrogenation of decene-1 with hydrogen accumulated in a hybrid carbon nanostructure in nanosized membrane reactors

    Science.gov (United States)

    Soldatov, A. P.

    2014-08-01

    Studies on the creation of nanosized membrane reactors (NMRs) of a new generation with accumulated hydrogen and a regulated volume of reaction zone were continued at the next stage. Hydrogenation was performed in the pores of ceramic membranes with hydrogen preliminarily adsorbed in mono- and multilayered orientated carbon nanotubes with graphene walls (OCNTGs)—a new hybrid carbon nanostructure formed on the inner pore surface. Quantitative determination of hydrogen adsorption in OCNTGs was performed using TRUMEM ultrafiltration membranes with D av = 50 and 90 nm and showed that hydrogen adsorption was up to ˜1.5% of the mass of OCNTG. The instrumentation and procedure for noncatalytic hydrogenation of decene-1 at 250-350°C using hydrogen accumulated and stored in OCNTG were developed. The conversion of decene-1 into decane was ˜0.2-1.8% at hydrogenation temperatures of 250 and 350°C, respectively. The rate constants and activation energy of hydrogenation were determined. The latter was found to be 94.5 kJ/mol, which is much smaller than the values typical for noncatalytic hydrogenations and very close to the values characteristic for catalytic reactions. The quantitative distribution of the reacting compounds in each pore regarded as a nanosized membrane reactor was determined. The activity of hydrogen adsorbed in a 2D carbon nanostructure was evaluated. Possible mechanisms of noncatalytic hydrogenation were discussed.

  3. Diffusion Monte Carlo simulations of gas phase and adsorbed D2-(H2)n clusters

    Science.gov (United States)

    Curotto, E.; Mella, M.

    2018-03-01

    We have computed ground state energies and analyzed radial distributions for several gas phase and adsorbed D2(H2)n and HD(H2)n clusters. An external model potential designed to mimic ionic adsorption sites inside porous materials is used [M. Mella and E. Curotto, J. Phys. Chem. A 121, 5005 (2017)]. The isotopic substitution lowers the ground state energies by the expected amount based on the mass differences when these are compared with the energies of the pure clusters in the gas phase. A similar impact is found for adsorbed aggregates. The dissociation energy of D2 from the adsorbed clusters is always much higher than that of H2 from both pure and doped aggregates. Radial distributions of D2 and H2 are compared for both the gas phase and adsorbed species. For the gas phase clusters, two types of hydrogen-hydrogen interactions are considered: one based on the assumption that rotations and translations are adiabatically decoupled and the other based on nonisotropic four-dimensional potential. In the gas phase clusters of sufficiently large size, we find the heavier isotopomer more likely to be near the center of mass. However, there is a considerable overlap among the radial distributions of the two species. For the adsorbed clusters, we invariably find the heavy isotope located closer to the attractive interaction source than H2, and at the periphery of the aggregate, H2 molecules being substantially excluded from the interaction with the source. This finding rationalizes the dissociation energy results. For D2-(H2)n clusters with n ≥12 , such preference leads to the desorption of D2 from the aggregate, a phenomenon driven by the minimization of the total energy that can be obtained by reducing the confinement of (H2)12. The same happens for (H2)13, indicating that such an effect may be quite general and impact on the absorption of quantum species inside porous materials.

  4. Recovery of iron oxides from acid mine drainage and their application as adsorbent or catalyst.

    Science.gov (United States)

    Flores, Rubia Gomes; Andersen, Silvia Layara Floriani; Maia, Leonardo Kenji Komay; José, Humberto Jorge; Moreira, Regina de Fatima Peralta Muniz

    2012-11-30

    Iron oxide particles recovered from acid mine drainage represent a potential low-cost feedstock to replace reagent-grade chemicals in the production of goethite, ferrihydrite or magnetite with relatively high purity. Also, the properties of iron oxides recovered from acid mine drainage mean that they can be exploited as catalysts and/or adsorbents to remove azo dyes from aqueous solutions. The main aim of this study was to recover iron oxides with relatively high purity from acid mine drainage to act as a catalyst in the oxidation of dye through a Fenton-like mechanism or as an adsorbent to remove dyes from an aqueous solution. Iron oxides (goethite) were recovered from acid mine drainage through a sequential precipitation method. Thermal treatment at temperatures higher than 300 °C produces hematite through a decrease in the BET area and an increase in the point of zero charge. In the absence of hydrogen peroxide, the solids adsorbed the textile dye Procion Red H-E7B according to the Langmuir model, and the maximum amount adsorbed decreased as the temperature of the thermal treatment increased. The decomposition kinetics of hydrogen peroxide is dependent on the H(2)O(2) concentration and iron oxides dosage, but the second-order rate constant normalized to the BET surface area is similar to that for different iron oxides tested in this and others studies. These results indicate that acid mine drainage could be used as a source material for the production of iron oxide catalysts/adsorbents, with comparable quality to those produced using analytical-grade reagents. Copyright © 2012 Elsevier Ltd. All rights reserved.

  5. Poorly crystalline hydroxyapatite: A novel adsorbent for enhanced fulvic acid removal from aqueous solution

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Wei [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023 (China); Yang, Lei; Zhong, Wenhui; Cui, Jing [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Wei, Zhenggui, E-mail: weizhenggui@gmail.com [Department of Environmental Science and Engineering, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Provincial Key Laboratory of Materials Cycling and Pollution Control, Nanjing Normal University, Nanjing 210023 (China); Jiangsu Center for Collaborative Innovation in Geographical Information Resource Development and Application, Nanjing Normal University, Nanjing 210023 (China)

    2015-03-30

    Graphical abstract: - Highlights: • Poorly crystalline HAP was firstly used for FA removal from aqueous solution. • The maximum adsorption capacity was determined to be 90.20 mg/g at 318 K. • Adsorption kinetics, isotherms and thermodynamic have been studied in detail. • Adsorption mechanism involved surface complexation, electrostatic interaction and hydrogen bonding. - Abstract: In this study, poorly crystalline hydroxyapatite (HAP) was developed as an efficient adsorbent for the removal of fulvic acid (FA) from aqueous solution. Surface functionality, crystallinity, and morphology of the synthetic adsorbent were studied by Fourier-transformation infrared (FT-IR) spectroscopy, powder X-ray diffraction (XRD) and transmission electron microscopy (TEM). The effects of various parameters such as crystallinity of adsorbent, contact time, adsorbent dosage, pH, initial adsorbate concentration, temperature, ionic strength and the presence of alkaline earth metal ions on FA adsorption were investigated. Results indicated that the nanosized HAP calcined at lower temperature was poorly crystalline (X{sub c} = 0.23) and had better adsorption capacity for FA than those (X{sub c} = 0.52, 0.86) calcined at higher temperature. FA removal was increased with increases of adsorbent dosage, temperature, ionic strength and the presence of alkali earth metal ions, but decreased as the pH increased. Kinetic studies showed that pseudo-second-order kinetic model better described the adsorption process. Equilibrium data were best described by Sips models, and the estimated maximum adsorption capacity of poorly crystalline HAP was 90.20 mg/g at 318 K, displaying higher efficiency for FA removal than previously reported adsorbents. FT-IR results revealed that FA adsorption over the adsorbent could be attributed to the surface complexation between the oxygen atom of functional groups of FA and calcium ions of HAP. Regeneration studies indicated that HAP could be recyclable for a long

  6. Energy: the solar hydrogen alternative

    Energy Technology Data Exchange (ETDEWEB)

    Bocheris, J O.M.

    1977-01-01

    The author argues that nuclear and solar energy should begin replacing conventional fossil sources as soon as possible because oil, gas and even coal supplies will be depleted within decades. A hydrogen economy would introduce major technical problems but its chief benefits are that it permits energy storage in a post fossil fuel era when electricity is expected to play a major role. It can be converted to electricity, cleanly and efficiently with fuel cells and in liquid form can be burnt as jet fuel. Hydrogen can also be burnt in internal combustion engines although less efficiently in fuel cells. However, although hydrogen is clean and efficient, technical development is still needed to reduce its cost and to cope with safety problems. The book contains a wealth of technical information and is a valuable reference on a topic of growing importance.

  7. Metallic → Semiconducting transitions in HX(X=F, Br, Cl) adsorbed (5,5) and (7,7) carbon nanotubes: DFT study

    Science.gov (United States)

    Srivastava, Reena; Shrivastava, Sadhana; Srivastava, Anurag

    2018-05-01

    The edge sensitivity of two different chirality (5,5) and (7,7) armchair carbon nanotubes towards toxic hydrogen halides (HF, HBr and HCl) has been analyzed by using density functional theory based ab-initio approach. The edge sensitivity has been discussed in terms of the variations in the electronic band structure of (5,5) and (7,7) carbon nanotube. The observation shows metallic to semiconducting phase transition in HF and HBr adsorbed (5,5) CNT, whereas for HCl adsorbed, it is more metallic. Whereas HBr and HCl adsorbed (7,7) CNT confirms metallic→semiconducting transition and shows diameter dependence of properties of CNTs.

  8. Volatile organic compounds adsorption using different types of adsorbent

    Directory of Open Access Journals (Sweden)

    Pimanmes Chanayotha

    2014-09-01

    Full Text Available Adsorbents were synthesized from coconut shell, coal and coke by pyrolysis followed by chemical activation process. These synthesized materials were used as adsorbents in adsorption test to determine the amount of volatile organic compounds (VOCs namely, 2-Hydroxyethyl methacrylate (HEMA, Octamethylcyclotetrasiloxane and Alkanes standard solution (C8-C20. The adsorption capacities of both synthesized adsorbents and commercial grade adsorbents (Carbotrap™ B and Carbotrap™ C were also compared. It was found that adsorbent A402, which was produced from coconut shell, activated with 40% (wt. potassium hydroxide and at activating temperature of 800°C for 1 hr, could adsorb higher amount of both HEMA and Octamethylcyclotetrasiloxane than other synthesized adsorbents. The maximum adsorption capacity of adsorbent A402 in adsorbing HEMA and Octamethylcyclotetrasiloxane were 77.87% and 50.82% respectively. These adsorption capabilities were 79.73% and 70.07% of the adsorption capacity of the commercial adsorbent Carbotrap™ B respectively. All three types of the synthesized adsorbent (A402, C302, C402 showed the capability to adsorb alkanes standard solution through the range of C8-C20 . However, their adsorption capacities were high in a specific range of C10-C11. The result from the isotherm plot was indicated that surface adsorption of synthesized adsorbent was isotherm type I while the surface adsorption of commercial adsorbent was isotherm type III.

  9. Hydrogen economy

    Energy Technology Data Exchange (ETDEWEB)

    Pahwa, P.K.; Pahwa, Gulshan Kumar

    2013-10-01

    In the future, our energy systems will need to be renewable and sustainable, efficient and cost-effective, convenient and safe. Hydrogen has been proposed as the perfect fuel for this future energy system. The availability of a reliable and cost-effective supply, safe and efficient storage, and convenient end use of hydrogen will be essential for a transition to a hydrogen economy. Research is being conducted throughout the world for the development of safe, cost-effective hydrogen production, storage, and end-use technologies that support and foster this transition. This book discusses hydrogen economy vis-a-vis sustainable development. It examines the link between development and energy, prospects of sustainable development, significance of hydrogen energy economy, and provides an authoritative and up-to-date scientific account of hydrogen generation, storage, transportation, and safety.

  10. Containment hydrogen removal system for a nuclear power plant

    International Nuclear Information System (INIS)

    Callaghan, V.M.; Flynn, E.P.; Pokora, B.M.

    1984-01-01

    A hydrogen removal system (10) separates hydrogen from the containment atmosphere of a nuclear power plant using a hydrogen permeable membrane separator (30). Water vapor is removed by condenser (14) from a gas stream withdrawn from the containment atmosphere. The gas stream is then compressed by compressor (24) and cooled (28,34) to the operating temperature of the hydrogen permeable membrane separator (30). The separator (30) separates the gas stream into a first stream, rich in hydrogen permeate, and a second stream that is hydrogen depleted. The separated hydrogen is passed through a charcoal adsorber (48) to adsorb radioactive particles that have passed through the hydrogen permeable membrane (44). The hydrogen is then flared in gas burner (52) with atmospheric air and the combustion products vented to the plant vent. The hydrogen depleted stream is returned to containment through a regenerative heat exchanger (28) and expander (60). Energy is extracted from the expander (60) to drive the compressor (24) thereby reducing the energy input necessary to drive the compressor (24) and thus reducing the hydrogen removal system (10) power requirements

  11. Photoemission spectroscopy of surfaces and adsorbates

    International Nuclear Information System (INIS)

    Chiang, T.C.; Kaindl, G.; Himpsel, F.J.; Eastman, D.E.

    1982-01-01

    Core level photoelectron spectroscopy is providing new information concerning the electronic properties of adsorbates and surfaces. Several examples will be discussed, including studies of adsorbed rare gas submonolayers and multilayers as well as clean metal surfaces. For rare gas multilayers adsorbed on metal surfaces, the photoelectrons and Auger electrons exhibit well-resolved increases in kinetic energy with decreasing distance between the excited atom and the substrate, allowing a direct labeling of the layers. These energy shifts are mainly due to the substrate screening effects, and can be described well by an image-charge model. For a Kr/Xe bilayer system prepared by first coating a Pd substrate with a monolayer of Kr and then overcoating with a layer of Xe, a thermally activated layer inversion process is observed when the temperature is raised, with Xe coming in direct contact with the substrate. For rare gas submonolayers adsorbed on the Al(111) surface, coverage-dependent core level shift and work function measurements provide information about the adatom spatial distributions, polarizabilities, and dipole moments for the ground and excited states. We have also studied the 2p core level shifts for a clean Al(001) surface relative to the bulk. The shifts have a large contribution from the initial-state effects

  12. Heterogeneous membranes filled with hypercrosslinked microparticle adsorbent

    Czech Academy of Sciences Publication Activity Database

    Hradil, Jiří; Krystl, V.; Hrabánek, P.; Bernauer, B.; Kočiřík, Milan

    2005-01-01

    Roč. 65, 1-2 (2005), s. 57-68 ISSN 1381-5148 R&D Projects: GA ČR GA104/03/0680 Institutional research plan: CEZ:AV0Z40500505 Keywords : heterogeneous membranes * hypercrosslinked adsorbent * microparticle s Subject RIV: CD - Macromolecular Chemistry Impact factor: 1.565, year: 2005

  13. Growth and hydrogenation of ultra-thin Mg films on Mo(111)

    DEFF Research Database (Denmark)

    Ostenfeld, Christopher Worsøe; Davies, Jonathan Conrad; Vegge, Tejs

    2005-01-01

    . Hydrogen cannot be adsorbed on magnesium films under UHV conditions. However, when evaporating Mg in a hydrogen background, a hydrogen overlayer is seen to adsorb at the Mg surface, due to the catalytic interaction with the Mo(1 1 1) substrate and subsequent spill-over. We show that two monolayers of Mg......The growth and hydrogenation of ultra-thin magnesium overlayers have been investigated on a Mo(1 1 1) single crystal substrate. For increasing magnesium coverages we observe intermediate stages in the TPD and LEISS profiles, which illustrate the transition from one monolayer to multilayer growth...

  14. Clarification of the mechanism of sulfur trioxide electrolysis. Evaluation of SO3 and O atom adsorbed on Pt surface

    International Nuclear Information System (INIS)

    Suzuki, Chikashi; Nakagiri, Toshio

    2008-01-01

    We developed a hybrid thermo-chemical process, which included a SO 3 electrolysis process utilizing the heat supplied by a fast breeder reactor (FBR), as a new hydrogen production process. To clarify the mechanism of SO 3 electrolysis, we evaluated the electronic states of SO 3 and O atom adsorbed on the Pt (111) surface using first-principles calculations with a slab model. Moreover, we evaluated the chemical bonding states of SO 3 and adsorbed O using molecular orbital calculation on the basis of the calculations using a slab model. We found that there were two stable adsorbed SO 3 configurations on the Pt surface. From the molecular orbital calculation, it was found that the S-O bond became weak by SO 3 absorption, and it was conjectured that SO 3 dissociation proceeded through the intermediate state of adsorbed SO 2 and adsorbed O on the Pt surface. Moreover, we derived the O coverage considering the adsorbed SO 2 and evaluated the influence of SO 3 adsorption energy on the O coverage. (author)

  15. Hydrogen safety

    International Nuclear Information System (INIS)

    Frazier, W.R.

    1991-01-01

    The NASA experience with hydrogen began in the 1950s when the National Advisory Committee on Aeronautics (NACA) research on rocket fuels was inherited by the newly formed National Aeronautics and Space Administration (NASA). Initial emphasis on the use of hydrogen as a fuel for high-altitude probes, satellites, and aircraft limited the available data on hydrogen hazards to small quantities of hydrogen. NASA began to use hydrogen as the principal liquid propellant for launch vehicles and quickly determined the need for hydrogen safety documentation to support design and operational requirements. The resulting NASA approach to hydrogen safety requires a joint effort by design and safety engineering to address hydrogen hazards and develop procedures for safe operation of equipment and facilities. NASA also determined the need for rigorous training and certification programs for personnel involved with hydrogen use. NASA's current use of hydrogen is mainly for large heavy-lift vehicle propulsion, which necessitates storage of large quantities for fueling space shots and for testing. Future use will involve new applications such as thermal imaging

  16. Band mapping of surface states vs. adsorbate coverage

    International Nuclear Information System (INIS)

    Rotenberg, E.; Kevan, S.D.; Denlinger, J.D.; Chung, Jin-Wook

    1997-01-01

    The theory of electron bands, which arises from basic quantum mechanical principles, has been the cornerstone of solid state physics for over 60 years. Simply put, an energy band is an electron state in a solid whose energy varies with its momentum (similar to, but with a more complicated dependence than, how a free electron's energy is proportional to its momentum squared). Much attention over the last 15 years has been given to the study of band structure of surfaces and interfaces, especially as the applications of these two-dimensional systems have become increasingly important to industry and science. The ultraESCA endstation at beamline 7.01 at the Advanced Light Source was developed for very high-energy - (∼50 meV) and angular - ( 12 photons/sec) makes the detailed study of the evolution of bands possible. The authors are interested in learning how, when one forms a chemical bond between a metal and an overlaying atom or molecule, the resulting charge transfer to or from the adsorbate affects the surface bands. In some cases of interest, intermediate coverages lead to different band structure than at the extremes of clean and saturated surfaces. Surfaces of tungsten are particularly interesting, as their atomic geometry has been shown to be exquisitely sensitive to both the surface vibrational and electronic properties. In this study, the authors looked at the surface bands of tungsten ((110) surface), as a function both of coverage and mass of overlaying atoms. The adsorbed atoms were hydrogen and the alkali atoms lithium and cesium

  17. Spin currents and filtering behavior in zigzag graphene nanoribbons with adsorbed molybdenum chains

    International Nuclear Information System (INIS)

    García-Fuente, A; Gallego, L J; Vega, A

    2015-01-01

    By means of density-functional-theoretic calculations, we investigated the structural, electronic and transport properties of hydrogen-passivated zigzag graphene nanoribbons (ZGNRs) on which a one-atom-thick Mo chain was adsorbed (with or without one or two missing atoms), or in which the passivating hydrogen atoms were replaced by Mo atoms. Mo-passivated ZGNRs proved to be nonmagnetic. ZGNRs with an adsorbed defect-free Mo chain were most stable with the Mo atoms forming dimers above edge bay sites, which suppressed the magnetic moments of the C atoms in that half of the ribbon; around the Fermi level of these systems, each spin component had a transmission channel via the Mo sp z band and one had an additional channel created by polarization of the ZGNR π * band, leading to a net spin current. The absence of an Mo dimer from an Mo chain adsorbed at the ZGNR edge made the system a perfect spin filter at low voltage bias by suppressing the Mo sp z band channels. Thus this last kind of hybrid system is a potential spin valve. (paper)

  18. PNNL Development and Analysis of Material-Based Hydrogen Storage Systems for the Hydrogen Storage Engineering Center of Excellence

    Energy Technology Data Exchange (ETDEWEB)

    Brooks, Kriston P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Alvine, Kyle J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Johnson, Kenneth I. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Klymyshyn, Nicholas A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pires, Richard P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Ronnebro, Ewa [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Simmons, Kevin L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Weimar, Mark R. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Westman, Matthew P. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

    2016-02-29

    The Hydrogen Storage Engineering Center of Excellence is a team of universities, industrial corporations, and federal laboratories with the mandate to develop lower-pressure, materials-based, hydrogen storage systems for hydrogen fuel cell light-duty vehicles. Although not engaged in the development of new hydrogen storage materials themselves, it is an engineering center that addresses engineering challenges associated with the currently available hydrogen storage materials. Three material-based approaches to hydrogen storage are being researched: 1) chemical hydrogen storage materials 2) cryo-adsorbents, and 3) metal hydrides. As a member of this Center, Pacific Northwest National Laboratory (PNNL) has been involved in the design and evaluation of systems developed with each of these three hydrogen storage materials. This report is a compilation of the work performed by PNNL for this Center.

  19. Hydrogen storage in graphitic nanofibres

    OpenAIRE

    McCaldin, Simon Roger

    2007-01-01

    There is huge need to develop an alternative to hydrocarbons fuel, which does not produce CO2 or contribute to global warming - 'the hydrogen economy' is such an alternative, however the storage of hydrogen is the key technical barrier that must be overcome. The potential of graphitic nanofibres (GNFs) to be used as materials to allow the solid-state storage of hydrogen has thus been investigated. This has been conducted with a view to further developing the understanding of the mechanism(s) ...

  20. Innovative Elution Processes for Recovering Uranium and Transition Metals from Amidoxime-based Adsorbents

    Energy Technology Data Exchange (ETDEWEB)

    Wai, Chien M. [Univ. of Idaho, Moscow, ID (United States). Dept. of Chemistry

    2017-04-18

    Amidoxime-based polymer fibers are considered one of the most promising materials for sequestering uranium from seawater. The high-surface-area polymer fibers containing amidoxime and carboxylate groups synthesized by Oak Ridge National Lab (ORNL-AF1) show very high uranium adsorption capacities known in the literature. Effective elution of uranium and repeated use of the adsorbent are important factors affecting the cost of producing uranium from seawater using this material. Traditional acid leaching of uranium followed by KOH conditioning of the fiber causes chemical changes and physical damage to the ORNL-AF1 adsorbent. Two alkaline solution leaching methods were developed by this project, one uses a highly concentrated (3 M) potassium bicarbonate solution at pH 8.3 and 40 °C; the other uses a mixture of sodium carbonate and hydrogen peroxide at pH 10.4. Both elution methods do not require KOH conditioning prior to reusing the fiber adsorbent. The conditions of eluting uranium from the amidoxime-based adsorbent using these alkaline solutions are confirmed by thermodynamic calculations. The bicarbonate elution method is selective for uranium recovery compared to other elution methods and causes no chemical change to the fiber material based on FTIR spectroscopy

  1. Controlled Hydrogen Fleet and Infrastructure Demonstration and Validation Project

    Energy Technology Data Exchange (ETDEWEB)

    Stottler, Gary

    2012-02-08

    General Motors, LLC and energy partner Shell Hydrogen, LLC, deployed a system of hydrogen fuel cell electric vehicles integrated with a hydrogen fueling station infrastructure to operate under real world conditions as part of the U.S. Department of Energy's Controlled Hydrogen Fleet and Infrastructure Validation and Demonstration Project. This technical report documents the performance and describes the learnings from progressive generations of vehicle fuel cell system technology and multiple approaches to hydrogen generation and delivery for vehicle fueling.

  2. The adsorber loop concept for the contact between seawater and adsorber granulate

    International Nuclear Information System (INIS)

    Koske, P.H.; Ohlrogge, K.

    1984-01-01

    The present paper deals with the so-called ''adsorber loop concept'' in which the adsorber granulate is carried along with the seawater to be processed in a loop-like configuration and is separated again from the depleted water before this is leaving the adsorption unit. This concept enables high seawater velocities thus reducing the required bed area. Theoretical considerations are presented together with experimental results from field tests. (orig.) [de

  3. Hydrogen storage in carbon nanotubes.

    Science.gov (United States)

    Hirscher, M; Becher, M

    2003-01-01

    The article gives a comprehensive overview of hydrogen storage in carbon nanostructures, including experimental results and theoretical calculations. Soon after the discovery of carbon nanotubes in 1991, different research groups succeeded in filling carbon nanotubes with some elements, and, therefore, the question arose of filling carbon nanotubes with hydrogen by possibly using new effects such as nano-capillarity. Subsequently, very promising experiments claiming high hydrogen storage capacities in different carbon nanostructures initiated enormous research activity. Hydrogen storage capacities have been reported that exceed the benchmark for automotive application of 6.5 wt% set by the U.S. Department of Energy. However, the experimental data obtained with different methods for various carbon nanostructures show an extreme scatter. Classical calculations based on physisorption of hydrogen molecules could not explain the high storage capacities measured at ambient temperature, and, assuming chemisorption of hydrogen atoms, hydrogen release requires temperatures too high for technical applications. Up to now, only a few calculations and experiments indicate the possibility of an intermediate binding energy. Recently, serious doubt has arisen in relation to several key experiments, causing considerable controversy. Furthermore, high hydrogen storage capacities measured for carbon nanofibers did not survive cross-checking in different laboratories. Therefore, in light of today's knowledge, it is becoming less likely that at moderate pressures around room temperature carbon nanostructures can store the amount of hydrogen required for automotive applications.

  4. Electronic spectral properties of surfaces and adsorbates and atom-adsorbate van der Waals interactions

    International Nuclear Information System (INIS)

    Lovric, D.; Gumhalter, B.

    1988-01-01

    The relevance of van der Waals interactions in the scattering of neutral atoms from adsorbates has been recently confirmed by highly sensitive molecular-beam techniques. The theoretical descriptions of the collision dynamics which followed the experimental studies have necessitated very careful qualitative and quantitative examinations and evaluations of the properties of atom-adsorbate van der Waals interactions for specific systems. In this work we present a microscopic calculation of the strengths and reference-plane positions for van der Waals potentials relevant for scattering of He atoms from CO adsorbed on various metallic substrates. In order to take into account the specificities of the polarization properties of real metals (noble and transition metals) and of chemisorbed CO, we first calculate the spectra of the electronic excitations characteristic of the respective electronic subsystems by using various data sources available and combine them with the existing theoretical models. The reliability of the calculated spectra is then verified in each particular case by universal sum rules which may be established for the electronic excitations of surfaces and adsorbates. The substrate and adsorbate polarization properties which derive from these calculations serve as input data for the evaluation of the strengths and reference-plane positions of van der Waals potentials whose computed values are tabulated for a number of real chemisorption systems. The implications of the obtained results are discussed in regard to the atom-adsorbate scattering cross sections pertinent to molecular-beam scattering experiments

  5. Importance of international standards on hydrogen technologies

    International Nuclear Information System (INIS)

    Bose, T.K.; Gingras, S.

    2001-01-01

    This presentation provided some basic information regarding standards and the International Organization for Standardization (ISO). It also explained the importance of standardization activities, particularly ISO/TC 197 which applies to hydrogen technologies. Standards are established by consensus. They define the minimum requirements that will ensure that products and services are reliable and effective. Standards contribute to the elimination of technical barriers to trade (TBT). The harmonization of standards around the world is desirable in a free trade environment. The influence of the TBT on international standardization was discussed with particular reference to the objectives of ISO/TC 197 hydrogen technologies. One of the priorities for ISO/TC 197 is a hydrogen fuel infrastructure which includes refuelling stations, fuelling connectors, and storage technologies for gaseous and liquid hydrogen. Other priorities include an agreement between the International Electrotechnical Commission (IEC) and the ISO, in particular the IEC/TC 105 and ISO/TC 197 for the development of fuel cell standards. The international standards that have been published thus far include ISO 13984:1999 for liquid hydrogen, land vehicle fuelling system interface, and ISO 14687:1999 for hydrogen fuel product specification. Standards are currently under development for: liquid hydrogen; airport hydrogen fuelling facilities; gaseous hydrogen blends; basic considerations for the safety of hydrogen systems; gaseous hydrogen and hydrogen blends; and gaseous hydrogen for land vehicle filling connectors. It was concluded that the widespread use of hydrogen is dependent on international standardization

  6. Technical writing versus technical writing

    Science.gov (United States)

    Dillingham, J. W.

    1981-01-01

    Two terms, two job categories, 'technical writer' and 'technical author' are discussed in terms of industrial and business requirements and standards. A distinction between 'technical writing' and technical 'writing' is made. The term 'technical editor' is also considered. Problems inherent in the design of programs to prepare and train students for these jobs are discussed. A closer alliance between industry and academia is suggested as a means of preparing students with competent technical communication skills (especially writing and editing skills) and good technical skills.

  7. Hydrogen generation utilizing integrated CO2 removal with steam reforming

    Science.gov (United States)

    Duraiswamy, Kandaswamy; Chellappa, Anand S

    2013-07-23

    A steam reformer may comprise fluid inlet and outlet connections and have a substantially cylindrical geometry divided into reforming segments and reforming compartments extending longitudinally within the reformer, each being in fluid communication. With the fluid inlets and outlets. Further, methods for generating hydrogen may comprise steam reformation and material adsorption in one operation followed by regeneration of adsorbers in another operation. Cathode off-gas from a fuel cell may be used to regenerate and sweep the adsorbers, and the operations may cycle among a plurality of adsorption enhanced reformers to provide a continuous flow of hydrogen.

  8. Hydrogen millennium

    International Nuclear Information System (INIS)

    Bose, T.K.; Benard, P.

    2000-05-01

    The 10th Canadian Hydrogen Conference was held at the Hilton Hotel in Quebec City from May 28 to May 31, 2000. The topics discussed included current drivers for the hydrogen economy, the international response to these drivers, new initiatives, sustainable as well as biological and hydrocarbon-derived production of hydrogen, defense applications of fuel cells, hydrogen storage on metal hydrides and carbon nanostructures, stationary power and remote application, micro-fuel cells and portable applications, marketing aspects, fuel cell modeling, materials, safety, fuel cell vehicles and residential applications. (author)

  9. California Hydrogen Infrastructure Project

    Energy Technology Data Exchange (ETDEWEB)

    Heydorn, Edward C

    2013-03-12

    Air Products and Chemicals, Inc. has completed a comprehensive, multiyear project to demonstrate a hydrogen infrastructure in California. The specific primary objective of the project was to demonstrate a model of a real-world retail hydrogen infrastructure and acquire sufficient data within the project to assess the feasibility of achieving the nation's hydrogen infrastructure goals. The project helped to advance hydrogen station technology, including the vehicle-to-station fueling interface, through consumer experiences and feedback. By encompassing a variety of fuel cell vehicles, customer profiles and fueling experiences, this project was able to obtain a complete portrait of real market needs. The project also opened its stations to other qualified vehicle providers at the appropriate time to promote widespread use and gain even broader public understanding of a hydrogen infrastructure. The project engaged major energy companies to provide a fueling experience similar to traditional gasoline station sites to foster public acceptance of hydrogen. Work over the course of the project was focused in multiple areas. With respect to the equipment needed, technical design specifications (including both safety and operational considerations) were written, reviewed, and finalized. After finalizing individual equipment designs, complete station designs were started including process flow diagrams and systems safety reviews. Material quotes were obtained, and in some cases, depending on the project status and the lead time, equipment was placed on order and fabrication began. Consideration was given for expected vehicle usage and station capacity, standard features needed, and the ability to upgrade the station at a later date. In parallel with work on the equipment, discussions were started with various vehicle manufacturers to identify vehicle demand (short- and long-term needs). Discussions included identifying potential areas most suited for hydrogen fueling

  10. Adsorbents for radioactive organic solvent wastes

    International Nuclear Information System (INIS)

    Ichinose, Shigeo; Kiribayashi, Takehiko.

    1986-01-01

    Purpose: To enable to settle radioactive solvents such as tributyl phosphate (TBP) and n-dodecane as they are without using hydrophobicizing agent such as quaternary ammonium salts. Constitution: The adsorbents are prepared by replacing interlaminer ions of swelling-type synthetic mica with alkaline earth metals or metal ions. For instance, synthetic micas introduced with Zr 4+ or Ca 2+ between the layers provide quite different functions from those of starting materials due to the properties of ions introduced between the layers. That is, they provide an intense affinity to organic phosphates such as TBP and transform into material showing a property of adsorbing and absorbing them. Particularly, the fixing nature to the phosphor content constituting TBP is significantly increased. (Horiuchi, T.)

  11. Zeolites as alcohol adsorbents from aqueous solutions

    Directory of Open Access Journals (Sweden)

    Cekova Blagica

    2006-01-01

    Full Text Available The potential usage of zeolites as adsorbents for the removal of organic molecules from water was investigated in a series of experiments with aqueous solutions of lower alcohols. This could represent a simple solution to the problem of cleaning up industrial wastewater as well as recovering valuable chemicals at relatively low costs. Adsorption isotherms of the Langmuir type were applied, and calculations showed that the amount of propanol adsorbed on silicalite corresponded to approximately 70% of the pore volume. The adsorption process is simple, and recovery of the more concentrated products is easily done by heat treatment and/or at lowered pressures. Adsorption experiments with aqueous acetone showed that silicalite had approximately the same adsorption capacity for acetone as for n-propanol. Heats of adsorption were determined calorimetrically.

  12. Analysis of Adsorbed Natural Gas Tank Technology

    Science.gov (United States)

    Knight, Ernest; Schultz, Conrad; Rash, Tyler; Dohnke, Elmar; Stalla, David; Gillespie, Andrew; Sweany, Mark; Seydel, Florian; Pfeifer, Peter

    With gasoline being an ever decreasing finite resource and with the desire to reduce humanity's carbon footprint, there has been an increasing focus on innovation of alternative fuel sources. Natural gas burns cleaner, is more abundant, and conforms to modern engines. However, storing compressed natural gas (CNG) requires large, heavy gas cylinders, which limits space and fuel efficiency. Adsorbed natural gas (ANG) technology allows for much greater fuel storage capacity and the ability to store the gas at a much lower pressure. Thus, ANG tanks are much more flexible in terms of their size, shape, and weight. Our ANG tank employs monolithic nanoporous activated carbon as its adsorbent material. Several different configurations of this Flat Panel Tank Assembly (FPTA) along with a Fuel Extraction System (FES) were examined to compare with the mass flow rate demands of an engine.

  13. Green Adsorbents for Wastewaters: A Critical Review

    Directory of Open Access Journals (Sweden)

    George Z. Kyzas

    2014-01-01

    Full Text Available One of the most serious environmental problems is the existence of hazardous and toxic pollutants in industrial wastewaters. The major hindrance is the simultaneous existence of many/different types of pollutants as (i dyes; (ii heavy metals; (iii phenols; (iv pesticides and (v pharmaceuticals. Adsorption is considered to be one of the most promising techniques for wastewater treatment over the last decades. The economic crisis of the 2000s led researchers to turn their interest in adsorbent materials with lower cost. In this review article, a new term will be introduced, which is called “green adsorption”. Under this term, it is meant the low-cost materials originated from: (i agricultural sources and by-products (fruits, vegetables, foods; (ii agricultural residues and wastes; (iii low-cost sources from which most complex adsorbents will be produced (i.e., activated carbons after pyrolysis of agricultural sources. These “green adsorbents” are expected to be inferior (regarding their adsorption capacity to the super-adsorbents of previous literature (complex materials as modified chitosans, activated carbons, structurally-complex inorganic composite materials etc., but their cost-potential makes them competitive. This review is a critical approach to green adsorption, discussing many different (maybe in some occasions doubtful topics such as: (i adsorption capacity; (ii kinetic modeling (given the ultimate target to scale up the batch experimental data to fixed-bed column calculations for designing/optimizing commercial processes and (iii critical techno-economical data of green adsorption processes in order to scale-up experiments (from lab to industry with economic analysis and perspectives of the use of green adsorbents.

  14. Generating Atomistic Slab Surfaces with Adsorbates

    Science.gov (United States)

    2017-12-01

    slabs of various thickness and with various vacuum spacing need be calculated. This can occur in serial or simultaneously . If performed in serial, the...the user. Although the optimization of the slab thickness and vacuum padding can be done simultaneously , it is more computationally conservative to...monolayer is a slab (True if slab), the type of mesh desired (adsorbates.py was written for “Gamma”), how detailed the mesh should be (in units of inverse

  15. Green Adsorbents for Wastewaters: A Critical Review

    Science.gov (United States)

    Kyzas, George Z.; Kostoglou, Margaritis

    2014-01-01

    One of the most serious environmental problems is the existence of hazardous and toxic pollutants in industrial wastewaters. The major hindrance is the simultaneous existence of many/different types of pollutants as (i) dyes; (ii) heavy metals; (iii) phenols; (iv) pesticides and (v) pharmaceuticals. Adsorption is considered to be one of the most promising techniques for wastewater treatment over the last decades. The economic crisis of the 2000s led researchers to turn their interest in adsorbent materials with lower cost. In this review article, a new term will be introduced, which is called “green adsorption”. Under this term, it is meant the low-cost materials originated from: (i) agricultural sources and by-products (fruits, vegetables, foods); (ii) agricultural residues and wastes; (iii) low-cost sources from which most complex adsorbents will be produced (i.e., activated carbons after pyrolysis of agricultural sources). These “green adsorbents” are expected to be inferior (regarding their adsorption capacity) to the super-adsorbents of previous literature (complex materials as modified chitosans, activated carbons, structurally-complex inorganic composite materials etc.), but their cost-potential makes them competitive. This review is a critical approach to green adsorption, discussing many different (maybe in some occasions doubtful) topics such as: (i) adsorption capacity; (ii) kinetic modeling (given the ultimate target to scale up the batch experimental data to fixed-bed column calculations for designing/optimizing commercial processes) and (iii) critical techno-economical data of green adsorption processes in order to scale-up experiments (from lab to industry) with economic analysis and perspectives of the use of green adsorbents. PMID:28788460

  16. Adsorbate Diffusion on Transition Metal Nanoparticles

    Science.gov (United States)

    2015-01-01

    correlation is a Bronsted-Evans-Polanyi ( BEP )- type of correlation, similar to other BEP correlations established earlier for surface-catalyzed bond- breaking...bond-making reactions.6-9 The universal BEP -type correlation is independent of the nature of the adsorbed species and that of the metal surface. For...a certain class of surface-catalyzed reactions, the existence of a BEP -type correlation reflects a similarity between the geometry of the transition

  17. Theoretical Insight of Physical Adsorption for a Single-Component Adsorbent + Adsorbate System: I. Thermodynamic Property Surfaces

    KAUST Repository

    Chakraborty, Anutosh; Saha, Bidyut Baran; Ng, Kim Choon; Koyama, Shigeru; Srinivasan, Kandadai

    2009-01-01

    Thermodynamic property surfaces for a single-component adsorbent + adsorbate system are derived and developed from the viewpoint of classical thermodynamics, thermodynamic requirements of chemical equilibrium, Gibbs law, and Maxwell relations

  18. Biological adsorbent for water decontamination from uranium

    Energy Technology Data Exchange (ETDEWEB)

    Jilek, R [Vyzkumny Ustav Veterinarniho Lekarstvi, Brno-Medlanky (Czechoslovakia); Fuska, J; Nemec, P [Slovenska Vysoka Skola Technicka, Bratislava (Czechoslovakia). Chemickotechnologicka Fakulta

    1978-01-01

    A study was made into the capacity of native and heat-denaturated mycelium to adsorb uranium salts from solutions and into the effect of uranium on the growth of the microorganism biomass. The presence of uranium did not inhibit the growth of Penicillium and Aspergillus strains used at a concentration of up to 5x10/sup -4/ M/dm/sup 3/. Uranium added to a nutrient medium produced complexes with phosphorus ions which were adsorbed on the surface of growing hyphae, thus the removal of the mycelium also removed uranium. The results of the experiments with denaturated mycelium of the same strains suggested that uranium was also bound to the biomass with chemical bonds so that mycelium acted as a ''multifunction ion exchanger'' from which adsorbed uranium can be removed step by step by elution. A sorbent of a three-dimensional structure could be prepared from a dried native mycelium using reinforcing resins, which prevented leakage of the biomass. Uranium sorption by biosorbents is a function of the concentration of the cation sorbed and of the pH of the solution.

  19. Biological adsorbent for water decontamination from uranium

    International Nuclear Information System (INIS)

    Jilek, R.; Fuska, J.; Nemec, P.

    1978-01-01

    A study was made into the capacity of native and heat-denaturated mycelium to adsorb uranium salts from solutions and into the effect of uranium on the growth of the microorganism biomass. The presence of uranium did not inhibit the growth of Penicillium and Aspergillus strains used at a concentration of up to 5x10 -4 M/dm 3 . Uranium added to a nutrient medium produced complexes with phosphorus ions which were adsorbed on the surface of growing hyphae, thus the removal of the mycelium also removed uranium. The results of the experiments with denaturated mycelium of the same strains suggested that uranium was also bound to the biomass with chemical bonds so that mycelium acted as a ''multifunction ion exchanger'' from which adsorbed uranium can be removed step by step by elution. A sorbent of a three-dimensional structure could be prepared from a dried native mycelium using reinforcing resins, which prevented leakage of the biomass. Uranium sorption by biosorbents is a function of the concentration of the cation sorbed and of the pH of the solution. (author)

  20. Characterisation of lignite as an industrial adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Ying Qi; Andrew F.A. Hoadley; Alan L. Chaffee; Gil Garnier [Monash University, Clayton, Vic. (Australia). Department of Chemical Engineering

    2011-04-15

    An alternative use of the abundant and inexpensive lignite (also known as brown coal) as an industrial adsorbent has been characterised. The adsorptive properties of two Victorian lignite without any pre-treatment were investigated using the cationic methylene blue dye as a model compound in aqueous solutions. Two commercial activated carbon products were also studied for comparison. The adsorption equilibrium of the four adsorbents was better described by the Langmuir isotherm model than the Freundlich model. The adsorption capacities of the two untreated lignite adsorbents, Loy Yang and Yallourn, calculated using Langmuir isotherms were 286 and 370 mg/g, respectively, higher than a coconut shell-based activated carbon (167 mg/g), but lower than a coal-based activated carbon (435 mg/g). Surface area results suggested that larger micropores and mesopores were important for achieving good methylene blue adsorption by the activated carbons. However, FTIR and cation exchange capacity analyses revealed that, for the lignite, chemical interactions between lignite surface functional groups and methylene blue molecules occurred, thereby augmenting its adsorption capacity. 63 refs., 3 figs., 7 tabs.

  1. Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion

    Directory of Open Access Journals (Sweden)

    Katsuaki Tanabe

    2016-01-01

    Full Text Available We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

  2. Modeling of hydrogen/deuterium dynamics and heat generation on palladium nanoparticles for hydrogen storage and solid-state nuclear fusion.

    Science.gov (United States)

    Tanabe, Katsuaki

    2016-01-01

    We modeled the dynamics of hydrogen and deuterium adsorbed on palladium nanoparticles including the heat generation induced by the chemical adsorption and desorption, as well as palladium-catalyzed reactions. Our calculations based on the proposed model reproduce the experimental time-evolution of pressure and temperature with a single set of fitting parameters for hydrogen and deuterium injection. The model we generated with a highly generalized set of formulations can be applied for any combination of a gas species and a catalytic adsorbent/absorbent. Our model can be used as a basis for future research into hydrogen storage and solid-state nuclear fusion technologies.

  3. Hydrogen exchange

    DEFF Research Database (Denmark)

    Jensen, Pernille Foged; Rand, Kasper Dyrberg

    2016-01-01

    Hydrogen exchange (HX) monitored by mass spectrometry (MS) is a powerful analytical method for investigation of protein conformation and dynamics. HX-MS monitors isotopic exchange of hydrogen in protein backbone amides and thus serves as a sensitive method for probing protein conformation...... and dynamics along the entire protein backbone. This chapter describes the exchange of backbone amide hydrogen which is highly quenchable as it is strongly dependent on the pH and temperature. The HX rates of backbone amide hydrogen are sensitive and very useful probes of protein conformation......, as they are distributed along the polypeptide backbone and form the fundamental hydrogen-bonding networks of basic secondary structure. The effect of pressure on HX in unstructured polypeptides (poly-dl-lysine and oxidatively unfolded ribonuclease A) and native folded proteins (lysozyme and ribonuclease A) was evaluated...

  4. Hydrogen storage in nanostructured materials

    Energy Technology Data Exchange (ETDEWEB)

    Assfour, Bassem

    2011-02-28

    total hydrogen uptake at 77 K and 100 bar amounts to 7.8 wt.% comparable to the total uptake reported of MOF-177 (10 wt.%), which is a benchmark material for high pressure and low temperature H{sub 2} adsorption. Covalent organic frameworks are new class of nanoporous materials constructed solely from light elements (C, H, B, and O). The number of adsorption sites as well as the strength of adsorption are essential prerequisites for hydrogen storage in porous materials because they determine the storage capacity and the operational conditions. Currently, to the best of our knowledge, no experimental data are available on the position of preferential H{sub 2} adsorption sites in COFs. Molecular dynamics simulations were applied to determine the position of preferential hydrogen sites in COFs. Our results demonstrate that H{sub 2} molecule adsorbed at low temperature in seven different adsorption sites in COFs. The calculated adsorption energies are about 3 kJ/mol, comparable to that found for MOF systems. The gravimetric uptake for COF-108 reached 4.17 wt.% at room temperature and 100 bar, which makes this class of materials promising for hydrogen storage applications. (orig.)

  5. Adsorption process to recover hydrogen from feed gas mixtures having low hydrogen concentration

    Science.gov (United States)

    Golden, Timothy Christopher; Weist, Jr., Edward Landis; Hufton, Jeffrey Raymond; Novosat, Paul Anthony

    2010-04-13

    A process for selectively separating hydrogen from at least one more strongly adsorbable component in a plurality of adsorption beds to produce a hydrogen-rich product gas from a low hydrogen concentration feed with a high recovery rate. Each of the plurality of adsorption beds subjected to a repetitive cycle. The process comprises an adsorption step for producing the hydrogen-rich product from a feed gas mixture comprising 5% to 50% hydrogen, at least two pressure equalization by void space gas withdrawal steps, a provide purge step resulting in a first pressure decrease, a blowdown step resulting in a second pressure decrease, a purge step, at least two pressure equalization by void space gas introduction steps, and a repressurization step. The second pressure decrease is at least 2 times greater than the first pressure decrease.

  6. Recovery of high-purity hydrogen from COG

    Energy Technology Data Exchange (ETDEWEB)

    Tsukiyama, Y

    1982-01-01

    A general account of the latest trends in the recovery of high-purity hydrogen from coke oven gas (COG), the article being based on both Japanese and overseas literature: 1) Deep-freeze separation: impurities are liquefied and removed. This method make use of the fact that hydrogen is hard to liquefy. 2) The PSA method: high-purity hydrogen is recovered by the adsorption of other constituents at high pressures. This technique makes use of the fact that the adsorption capacity of an adsorbent varies with the partial pressure of the substances being adsorbed. 3) Membrane separation: a permeation separation method that uses a functional polymer separation membrane, and that depends on the fact that hydrogen has a low molecular weight in comparison with the other constituents. (19 refs.) (In Japanese)

  7. Effect of hydrogen coverage on hydrogenation of o-cresol on Pt(111)

    Science.gov (United States)

    Li, Yaping; Liu, Zhimin; Crossley, Steven P.; Jentoft, Friederike C.; Wang, Sanwu

    2018-06-01

    The conversion of phenolics over metal catalysts is an important process for upgrading biofuels. With density functional calculations, hydrogenation of o-cresol on the hydrogen-covered Pt(111) surface was investigated. The results show that the coverage of hydrogen plays a significant role in the reaction rate while it does not affect the reaction selectivity. The reaction barriers of the hydrogenation process leading to the formation of both 2-methyl-cyclohexanone (the intermediate product) and 2-methyl-cyclohexanol (the final product) at high H coverages (∼1 ML) are found to be smaller by 0.14-0.69 eV than those at lower H coverages (∼1/25 ML). After both hydrogen and cresol are adsorbed on Pt(111) from their initial gas phase state, the reaction energy of each hydrogenation step on the surface is also dependent on the hydrogen coverage. On the H-covered Pt(111) surface, most steps of hydrogenation involve exothermic reactions when the hydrogen coverage is high while they are endothermic reactions at low hydrogen coverages. The differences in reaction rate and reaction energy between high and low H coverages can be understood with the coverage-dependent bonding strength and configurations.

  8. Cost analysis of seawater uranium recovered by a polymeric adsorbent system

    International Nuclear Information System (INIS)

    Schneider, E.; Lindner, H.; Sachde, D.; Flicker, M.

    2014-01-01

    In tandem with its adsorbent development and marine testing efforts, the United States Department of Energy, Office of Nuclear Energy, routinely updates and expands its cost analysis of technologies for extracting uranium from seawater. If informed by repeatable data from field tests, a rigorous cost analysis can convincingly establish seawater uranium as a “backstop” to conventional uranium resources. A backstop provides an essentially unlimited supply of an otherwise exhaustible resource. Its role is to remove the uncertainty around the long-term sustainability of the resource. The cost analysis ultimately aims to demonstrate a uranium production cost that is sustainable for the nuclear power industry, with no insurmountable technical or environmental roadblocks. It is also a tool for guiding further R&D, identifying inputs and performance factors where further development would offer the greatest reduction in costs and/or uncertainties. A life cycle discounted cash flow methodology is used to calculate the uranium production cost and its uncertainty from the costs of fundamental inputs including chemicals and materials, labor, equipment, energy carriers and facilities. The inputs themselves are defined by process flow models of the adsorbent fabrication and grafting, mooring at sea, recovery, and elution and purification steps in the seawater uranium recovery process. Pacific Northwest National Laboratory (PNNL) has carried out marine tests of the Oak Ridge National Laboratory amidoxime grafted polymer adsorbent in natural seawater. Multiple test campaigns demonstrated that after 60 days of immersion the uranium uptake averaged 3090 ± 310 μg U/g of adsorbent. Past ocean experiments on similar material by the Japan Atomic Energy Agency (JAEA) demonstrated that the adsorbent may be used in the sea six times before being replaced, with 5% uptake degradation per reuse. The mooring and recovery system envisioned for the adsorbent is similar to one proposed by

  9. Removal of adsorbent particles od copper ions by Jet flotation

    International Nuclear Information System (INIS)

    Santander, M.; Tapia, P.; Pavez, O.; Valderrama, L.; Guzman, D.

    2009-01-01

    The present study shows the results obtained on the removal of copper ions from synthetic effluents by using the adsorbent particles flotation technique (APF) in a Jet flotation cell (Jameson type). In a typical experimental run, a mineral with high quartz content was used as adsorbent particles in the adsorption and flotation experiments, to determine optimal pH conditions, adsorbent particles concentration; flotation reagents dosage and air/effluent flow ratio for applying in the Jet cell to maximize the efficiency of copper ions adsorptions and the removal of particles adsorbents containing the absorbed copper ions. The results indicate the at pH>7 and at adsorbent particles concentration of 2 kg.m - 3, 99% of copper ions is adsorbed and, when the air/effluent flow ratio applied in the Jet cell is 0,2, 98% of absorbent particles containing the adsorbed copper ions is removed. (Author) 39 refs.

  10. Sorption of CO 2 in a hydrogen-bonded diamondoid network of sulfonylcalix[4]arene

    Energy Technology Data Exchange (ETDEWEB)

    Sinnwell, Michael A. [Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland, WA, USA; Atwood, Jerry L. [Department of Chemistry, University of Missouri-Columbia, Columbia, MO, USA; Thallapally, Praveen K. [Physical and Computational Science Directorate, Pacific Northwest National Laboratory, Richland, WA, USA

    2018-02-08

    An organic material, p-tert-butyltetrasulfonylcalix[4]arene, self-assembles via hydrogen bonding to form a diamondoid supramolecular network. Possessing discrete, zero-dimensional (0D) microcavities, the thiacalixarene derivative adsorbs CO2 at high pressures

  11. Hydrogen adsorption on partially oxidised microporous carbons

    International Nuclear Information System (INIS)

    J B Parra; C O Ania; C J Duran Valle; M L Sanchez; C Otero Arean

    2005-01-01

    The search for cost effective adsorbents for large scale gas separation, storage and transport constitutes a present day strategic issue in the energy sector, propelled mainly by the potential use of hydrogen as an energy vector in a sustainable (and cleaner) energy scenario. Both, activated carbons and carbon based nano-structured materials have been proposed as potential candidates for reversible hydrogen storage in cryogenically cooled vessels. For that purpose, surface modification so as to enhance the gas solid interaction energy is desirable. We report on hydrogen adsorption on microporous (active) carbons which have been partially oxidised with nitric acid and ammonium persulfate. From the corresponding hydrogen adsorption isotherms (Fig. 1) an isosteric heat of about 3 kJ mol -1 was derived. This value is in agreement with that of about 3 to 4 kJ mol -1 obtained by quantum chemical calculations on the interaction between the hydrogen molecule and simple model systems (Fig. 2) of both, hydroxyl and carboxyl groups. Further research is in progress with a view to further increases the gas solid interaction energy. However, the values so far obtained are significantly larger than the liquefaction enthalpy of hydrogen: 0.90 kJ mol -1 ; and this is relevant to both, hydrogen separation from gas mixtures and cryogenic hydrogen storage. (authors)

  12. A nuclear based hydrogen economy

    International Nuclear Information System (INIS)

    Sandquist, G.M.; Tamm, G.; Kunze, J.

    2005-01-01

    Exhausting demands are being imposed upon the world's ability to extract and deliver oil to the nations demanding fluid fossil fuels. This paper analyzes these issues and concludes that there must be no delay in beginning the development of the 'hydrogen economy' using nuclear energy as the primary energy source to provide both the fluid fuel and electrical power required in the 21st century. Nuclear energy is the only proven technology that is abundant and available worldwide to provide the primary energy needed to produce adequate hydrogen fluid fuel supplies to replace oil. Most importantly, this energy transition can be accomplished in an economical and technically proven manner while lowering greenhouse gas emissions. Furthermore, a similar application of using wind and solar to produce hydrogen instead of electricity for the grid can pave the way for the much larger production scales of nuclear plants producing both electricity and hydrogen. (authors)

  13. Questioning hydrogen

    International Nuclear Information System (INIS)

    Hammerschlag, Roel; Mazza, Patrick

    2005-01-01

    As an energy carrier, hydrogen is to be compared to electricity, the only widespread and viable alternative. When hydrogen is used to transmit renewable electricity, only 51% can reach the end user due to losses in electrolysis, hydrogen compression, and the fuel cell. In contrast, conventional electric storage technologies allow between 75% and 85% of the original electricity to be delivered. Even when hydrogen is extracted from gasified coal (with carbon sequestration) or from water cracked in high-temperature nuclear reactors, more of the primary energy reaches the end user if a conventional electric process is used instead. Hydrogen performs no better in mobile applications, where electric vehicles that are far closer to commercialization exceed fuel cell vehicles in efficiency, cost and performance. New, carbon-neutral energy can prevent twice the quantity of GHG's by displacing fossil electricity than it can by powering fuel cell vehicles. The same is true for new, natural gas energy. New energy resources should be used to displace high-GHG electric generation, not to manufacture hydrogen

  14. Development of adsorbents for recovery of uranium from seawater

    International Nuclear Information System (INIS)

    Egawa, Hiroaki; Furusaki, Shintaro.

    1987-01-01

    The largest subject for putting the extraction of uranium from seawater in practical use is the development of high performance adsorbents for uranium. In this paper, the way of thinking about the development of adsorbents for extracting uranium from seawater and the recent reports on this subject are described. Next, the research on the adsorbing capacity and adsorbing rate of the adsorbents developed so far is summarized, and the way of thinking about the evaluation of adsorbent performance which is the base of the design of a system for extracting uranium from seawater is explained, taking amidoxime type adsorbent as the example. For Japan where energy resources are scant, the uranium contained in seawater, which is estimated to be about 4.2 billion t, is the most luring important element. Uranium is contained in seawater is very low concentration of 3 ppb, and exists as anion complex salt. In 1960s, the Harwell Atomic Energy Research Establishment in UK found out that titanium oxide hydrate is the most promising as the adsorbent. Also a number of organic absorbents have been developed. In order to bring adsorbents in contact with seawater, pumping, ocean current and wave force are utilized. Adsorbents are in spherical, fiber and film forms, and held as fixed beds and fluidized beds. (Kako, I.) 48 refs

  15. Electrochemical reduction of hydrogen peroxide on stainless steel

    Indian Academy of Sciences (India)

    Administrator

    wide range of industrial processes such as food processing (e.g. in the ... tron transfer effect of mitochondria.4 These radicals. (reactive .... of H2O2 without undergoing fouling or poisoning due to any inter- .... adsorbed OHads species was shown operative at po- tentials of .... Douglass W C 2003 Hydrogen peroxide medical.

  16. SISGR - Hydrogen Caged in Carbon-Exploration of Novel Carbon-Hydrogen Interactions

    Energy Technology Data Exchange (ETDEWEB)

    Lueking, Angela [Pennsylvania State Univ., State College, PA (United States); Badding, John [Pennsylvania State Univ., State College, PA (United States); Crespi, Vinent [Pennsylvania State Univ., State College, PA (United States)

    2015-12-01

    Hydrogen trapped in a carbon cage, captured through repulsive interactions, is a novel concept in hydrogen storage. Trapping hydrogen via repulsive interactions borrows an idea from macroscale hydrogen storage (i.e. compressed gas storage tanks) and reapplies these concepts on the nanoscale in specially designed molecular containers. Under extreme conditions of pressure, hydrogen solubility in carbon materials is expected to increase and carbon is expected to restructure to minimize volume via a mixed sp2/sp3 hydrogenated state. Thermodynamics dictate that pre-formed C-H structures will rearrange with increased pressure, yet the final carbon-hydrogen interactions may be dependent upon the mechanism by which hydrogen is introduced. Gas “trapping” is meant to denote gas present in a solid in a high density, adsorbed-like state, when the external pressure is much less than that necessary to provide a comparable fluid density. Trapping thus denotes a kinetically metastable state rather than thermodynamic equilibrium. This project probed mechanochemical means to polymerize select hydrocarbons in the presence of gases, in an attempt to form localized carbon cages that trap gases via repulsive interactions. Aromatic, polyaromatic, and hydroaromatic molecules expected to undergo cyclo-addition reactions were polymerized at high (~GPa) pressures to form extended hydrogenated amorphous carbon networks. Notably, aromatics with a pre-existing internal free volume (such as Triptycene) appeared to retain an internal porosity upon application of pressure. However, a high photoluminescence background after polymerization precluded in situ identification of trapped gases. No spectroscopic evidence was found after depressurization that would be indicative of pockets of trapped gases in a localized high-pressure environment. Control studies suggested this measurement may be insensitive to gases at low pressure. Similarly, no spectral fingerprint was found for gas-imbued spherical

  17. Hydrogen storage technology materials and applications

    CERN Document Server

    Klebanoff, Lennie

    2012-01-01

    Zero-carbon, hydrogen-based power technology offers the most promising long-term solution for a secure and sustainable energy infrastructure. With contributions from the world's leading technical experts in the field, Hydrogen Storage Technology: Materials and Applications presents a broad yet unified account of the various materials science, physics, and engineering aspects involved in storing hydrogen gas so that it can be used to provide power. The book helps you understand advanced hydrogen storage materials and how to build systems around them. Accessible to nonscientists, the first chapt

  18. Theoretical Insight of Physical Adsorption for a Single Component Adsorbent + Adsorbate System: II. The Henry Region

    KAUST Repository

    Chakraborty, Anutosh; Saha, Bidyut Baran; Ng, Kim Choon; Koyama, Shigeru; Srinivasan, Kandadai

    2009-01-01

    evaluated and compared with experimental data. It is found that the adsorbents with higher specific surface areas tend to possess lower heat of adsorption (ΔH°) at the Henry regime. In this paper, we have established the definitive relation between Ai and ΔH

  19. Natural adsorbents of dyes from aqueous solution

    Science.gov (United States)

    Rahmani, Meryem; El Hajjaji, souad; Dahchour, Abdelmalek; El M'Rabet, Mohammadine

    2017-04-01

    Contamination of natural waters is a current environmental problem and lot of work has been done to find methods for its, prevention and remediation such as ionic exchange, adsorption on active carbon, filtration, electrolysis, biodegradation …etc. Adsorption is one of the most applied methods according to its effectiveness and easy management. Some adsorbents with good properties such as active alumina, zeolites, crop residues … etc, are suitable to substitute usual active carbon. This study aimed at the removal of dyes using oil shale as natural support, and its optimization by factorial experiment. Three factors were considered namly:pollutant concentration, pH and weight of the adsorbent. Tests have been performed with cationic and anionic dyes. Experimental results show that pseudo-first-order kinetic model provided the best fit to the experimental data for the adsorption by the oil shale. Langmuir, Freundlich and Temkin isotherm models were tested to fit experimental data, the adsorption equilibrium was well described by Freundlich isotherm for methylorange and Temkin for methyl blue. Analysis were completed by oil shale characterization educing XRD, IR, XRF techniques, and cationic exchange capacity.

  20. Optimizing heterosurface adsorbent synthesis for liquid chromatography

    Science.gov (United States)

    Bogoslovskii, S. Yu.; Serdan, A. A.

    2016-03-01

    The structural and geometric parameters of a silica matrix (SM) for the synthesis of heterosurface adsorbents (HAs) are optimized. Modification is performed by shielding the external surfaces of alkyl-modified silica (AS) using human serum albumin and its subsequent crosslinking. The structural and geometric characteristics of the SM, AS, and HA are measured via low-temperature nitrogen adsorption. It is found that the structural characteristics of AS pores with diameters D 9 nm reduces significantly due to adsorption of albumin. It is concluded that silica gel with a maximum pore size distribution close to 5 nm and a minimal proportion of pores with D > 9 nm is optimal for HA synthesis; this allows us to achieve the greatest similarity between the chromatographic retention parameters for HA and AS. The suitability of the synthesized adsorbents for analyzing drugs in biological fluids through direct sample injection is confirmed by chromatography. It was found that the percentage of the protein fraction detected at the outlet of the chromatographic column is 98%.

  1. Imagining Technicities

    DEFF Research Database (Denmark)

    Liboriussen, Bjarke; Plesner, Ursula

    2011-01-01

    to the elements of taste and skill. In the final analysis those references were synthesized as five imagined technicities: the architect, the engineer, the client, the Chinese, and the Virtual World native. Because technicities are often assumed and rarely discussed as actants who influence practice, their role......, this article focuses on innovative uses of virtual worlds in architecture. We interviewed architects, industrial designers and other practitioners. Conceptually supported by an understanding of technicity found in Cultural Studies, the interviews were then coded with a focus on interviewees’ references...... in cooperation and development of ICTs seems to pass unnoticed. However, since they are aligned into ICTs, technicities impact innovation....

  2. New type of amidoxime-group-containing adsorbent for the recovery of uranium from seawater. III. Recycle use of adsorbent

    International Nuclear Information System (INIS)

    Omichi, H.; Katakai, A.; Sugo, T.; Okamoto, J.

    1986-01-01

    An amidoxime-group adsorbent for recovering uranium from seawater was made by radiation-induced graft polymerization of acrylonitrile onto polymeric fiber, followed by amidoximation. Uranium adsorption of the adsorbent contacted with seawater in a column increased with the increase in flow rate, then leveled off. The relationship between uranium adsorption in a batch process and the ratio of the amount of seawater to that of adsorbent was found to be effective in evaluating adsorbent contacted with any amount of seawater. The conditioning of the adsorbent with an alkaline solution at higher temperature (∼80 0 C) after the acid desorption recovered the adsorption ability to the original level. This made it possible to apply the adsorbent to recycle use. On the other hand, the adsorbent conditioned at room temperature or that without conditioning lost adsorption ability during recycle use. The increase in water uptake was observed as one of the physical changes produced during recycle use of the alkaline-conditioned adsorbent, while the decrease in water uptake was observed with the unconditioned adsorbent. The IR spectra of the adsorbent showed a probability of reactions of amidoxime groups with acid and alkaline solutions, which can explain the change in uranium adsorption during the adsorption-desorption cycle

  3. Hydrogen Production from Nuclear Energy via High Temperature Electrolysis

    International Nuclear Information System (INIS)

    James E. O'Brien; Carl M. Stoots; J. Stephen Herring; Grant L. Hawkes

    2006-01-01

    This paper presents the technical case for high-temperature nuclear hydrogen production. A general thermodynamic analysis of hydrogen production based on high-temperature thermal water splitting processes is presented. Specific details of hydrogen production based on high-temperature electrolysis are also provided, including results of recent experiments performed at the Idaho National Laboratory. Based on these results, high-temperature electrolysis appears to be a promising technology for efficient large-scale hydrogen production

  4. Microporous Metal Organic Materials for Hydrogen Storage

    Energy Technology Data Exchange (ETDEWEB)

    S. G. Sankar; Jing Li; Karl Johnson

    2008-11-30

    We have examined a number of Metal Organic Framework Materials for their potential in hydrogen storage applications. Results obtained in this study may, in general, be summarized as follows: (1) We have identified a new family of porous metal organic framework materials with the compositions M (bdc) (ted){sub 0.5}, {l_brace}M = Zn or Co, bdc = biphenyl dicarboxylate and ted = triethylene diamine{r_brace} that adsorb large quantities of hydrogen ({approx}4.6 wt%) at 77 K and a hydrogen pressure of 50 atm. The modeling performed on these materials agree reasonably well with the experimental results. (2) In some instances, such as in Y{sub 2}(sdba){sub 3}, even though the modeling predicted the possibility of hydrogen adsorption (although only small quantities, {approx}1.2 wt%, 77 K, 50 atm. hydrogen), our experiments indicate that the sample does not adsorb any hydrogen. This may be related to the fact that the pores are extremely small or may be attributed to the lack of proper activation process. (3) Some samples such as Zn (tbip) (tbip = 5-tert butyl isophthalate) exhibit hysteresis characteristics in hydrogen sorption between adsorption and desorption runs. Modeling studies on this sample show good agreement with the desorption behavior. It is necessary to conduct additional studies to fully understand this behavior. (4) Molecular simulations have demonstrated the need to enhance the solid-fluid potential of interaction in order to achieve much higher adsorption amounts at room temperature. We speculate that this may be accomplished through incorporation of light transition metals, such as titanium and scandium, into the metal organic framework materials.

  5. Nanocrystalline electrodeposited Ni-Mo-C cathodes for hydrogen production

    International Nuclear Information System (INIS)

    Hashimoto, K.; Sasaki, T.; Meguro, S.; Asami, K.

    2004-01-01

    Tailoring active nickel alloy cathodes for hydrogen evolution in a hot concentrated hydroxide solution was attempted by electrodeposition. The carbon addition to Ni-Mo alloys decreased the nanocrystalline grain size and remarkably enhanced the activity for hydrogen evolution, changing the mechanism of hydrogen evolution. The Tafel slope of hydrogen evolution was about 35 mV per decade. This suggested that the rate-determining step is desorption of adsorbed hydrogen atoms by recombination. As was distinct from the binary Ni-Mo alloys, after open circuit immersion, the overpotential, that is, the activity of nanocrystalline Ni-Mo-C alloys for hydrogen evolution was not changed, indicating the sufficient durability in the practical electrolysis

  6. Polyaniline as a material for hydrogen storage applications.

    Science.gov (United States)

    Attia, Nour F; Geckeler, Kurt E

    2013-07-12

    The main challenge of commercialization of the hydrogen economy is the lack of convenient and safe hydrogen storage materials, which can adsorb and release a significant amount of hydrogen at ambient conditions. Finding and designing suitable cost-effective materials are vital requirements to overcome the drawbacks of investigated materials. Because of its outstanding electronic, thermal, and chemical properties, the electrically conducting polyaniline (PANI) has a high potential in hydrogen storage applications. In this review, the progress in the use of different structures of conducting PANI, its nanocomposites as well as activated porous materials based on PANI as hydrogen storage materials is presented and discussed. The effect of the unique electronic properties based on the π-electron system in the backbone of these materials in view of the hydrogen uptake and the relevant mechanisms are highlighted. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. The US Department of Energy hydrogen baseline survey: assessing knowledge and opinions about hydrogen technology

    International Nuclear Information System (INIS)

    Christy Cooper; Tykey Truett; R L Schmoyer

    2006-01-01

    To design and maintain its education program, the United States Department of Energy (DOE) Hydrogen Program conducted a statistically-valid national survey to measure knowledge and opinions of hydrogen among key target audiences. The Hydrogen Baseline Knowledge Survey provides a reference for designing the DOE hydrogen education strategy and will be used in comparisons with future surveys to measure changes in knowledge and opinions over time. The survey sampled four U.S. populations: (1) public; (2) students; (3) state and local government officials; and (4) potential large-scale hydrogen end-users in three business categories. Questions measured technical understanding of hydrogen and opinions about hydrogen safety. Other questions assessed visions of the likelihood of future hydrogen applications and sources of energy information. Several important findings were discovered, including a striking lack of technical understanding across all survey groups, as well as a strong correlation between technical knowledge and opinions about safety: those who demonstrated an understanding of hydrogen technologies expressed the least fear of its safe use. (authors)

  8. Economical and ecological comparison of granular activated carbon (GAC) adsorber refill strategies.

    Science.gov (United States)

    Bayer, Peter; Heuer, Edda; Karl, Ute; Finkel, Michael

    2005-05-01

    Technical constraints can leave a considerable freedom in the design of a technology, production or service strategy. Choosing between economical or ecological decision criteria then characteristically leads to controversial solutions of ideal systems. For the adaptation of granular-activated carbon (GAC) fixed beds, various technical factors determine the adsorber volume required to achieve a desired service life. In considering carbon replacement and recycling, a variety of refill strategies are available that differ in terms of refill interval, respective adsorber volume, and time-dependent use of virgin, as well as recycled GAC. Focusing on the treatment of contaminant groundwater, we compare cost-optimal reactor configurations and refill strategies to the ecologically best alternatives. Costs and consumption of GAC are quantified within a technical-economical framework. The emissions from GAC production out of hard coal, transport and recycling are equally derived through a life cycle impact assessment. It is shown how high discount rates lead to a preference of small fixed-bed volumes, and accordingly, a high number of refills. For fixed discount rates, the investigation reveals that both the economical as well as ecological assessment of refill strategies are especially sensitive to the relative valuation of virgin and recycled GAC. Since recycling results in economic and ecological benefits, optimized systems thus may differ only slightly.

  9. Hydrogen program overview

    Energy Technology Data Exchange (ETDEWEB)

    Gronich, S. [Dept. of Energy, Washington, DC (United States). Office of Utility Technologies

    1997-12-31

    This paper consists of viewgraphs which summarize the following: Hydrogen program structure; Goals for hydrogen production research; Goals for hydrogen storage and utilization research; Technology validation; DOE technology validation activities supporting hydrogen pathways; Near-term opportunities for hydrogen; Market for hydrogen; and List of solicitation awards. It is concluded that a full transition toward a hydrogen economy can begin in the next decade.

  10. Low concentration CO2 capture using physical adsorbents: Are Metal-Organic Frameworks becoming the new benchmark materials?

    KAUST Repository

    Belmabkhout, Youssef

    2016-03-30

    The capture and separation of traces and concentrated CO2 from important commodities such as CH4, H2, O2 and N2, is becoming important in many areas related to energy security and environmental sustainability. While trace CO2 concentration removal applications have been modestly studied for decades, the spike in interest in the capture of concentrated CO2 was motivated by the need for new energy vectors to replace highly concentrated carbon fuels and the necessity to reduce emissions from fossil fuel-fired power plants. CO2 capture from various gas streams, at different concentrations, using physical adsorbents, such as activated carbon, zeolites, and metal-organic frameworks (MOFs), is attractive. However, the adsorbents must be designed with consideration of many parameters including CO2 affinity, kinetics, energetics, stability, capture mechanism, in addition to cost. Here, we perform a systematic analysis regarding the key technical parameters that are required for the best CO2 capture performance using physical adsorbents. We also experimentally demonstrate a suitable material model of Metal Organic Framework as advanced adsorbents with unprecedented properties for CO2 capture in a wide range of CO2 concentration. These recently developed class of MOF adsorbents represent a breakthrough finding in the removal of traces CO2 using physical adsorption. This platform shows colossal tuning potential for more efficient separation agents.

  11. Low concentration CO2 capture using physical adsorbents: Are Metal-Organic Frameworks becoming the new benchmark materials?

    KAUST Repository

    Belmabkhout, Youssef; Guillerm, Vincent; Eddaoudi, Mohamed

    2016-01-01

    The capture and separation of traces and concentrated CO2 from important commodities such as CH4, H2, O2 and N2, is becoming important in many areas related to energy security and environmental sustainability. While trace CO2 concentration removal applications have been modestly studied for decades, the spike in interest in the capture of concentrated CO2 was motivated by the need for new energy vectors to replace highly concentrated carbon fuels and the necessity to reduce emissions from fossil fuel-fired power plants. CO2 capture from various gas streams, at different concentrations, using physical adsorbents, such as activated carbon, zeolites, and metal-organic frameworks (MOFs), is attractive. However, the adsorbents must be designed with consideration of many parameters including CO2 affinity, kinetics, energetics, stability, capture mechanism, in addition to cost. Here, we perform a systematic analysis regarding the key technical parameters that are required for the best CO2 capture performance using physical adsorbents. We also experimentally demonstrate a suitable material model of Metal Organic Framework as advanced adsorbents with unprecedented properties for CO2 capture in a wide range of CO2 concentration. These recently developed class of MOF adsorbents represent a breakthrough finding in the removal of traces CO2 using physical adsorption. This platform shows colossal tuning potential for more efficient separation agents.

  12. New Fiber Materials with Sorption Capacity at 5.0 g-U/kg Adsorbent under Marine Testing Conditions

    Energy Technology Data Exchange (ETDEWEB)

    Saito, Tomonori [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Brown, S. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Das, Sadananda [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Mayes, Richard T. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Janke, Christopher James [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Dai, Sheng [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Kuo, Li-Jung [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Strivens, Jonathan E. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Schlafer, Nicholas [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Wood, J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Gill, G. A. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Flicker Byers, M. [Univ. of Texas, Austin, TX (United States); Schneider, Eric [Univ. of Texas, Austin, TX (United States)

    2016-03-30

    The Fuel Resources program of the Fuel Cycle Research and Development program of the Office of Nuclear Energy (NE) has focused on assuring that nuclear fuel resources are available in the United States for a long term. An immense source of uranium is seawater, which contains an estimated amount of 4.5 billion tonnes of dissolved uranium. Extraction of the uranium resource in seawater can provide a price cap and ensure centuries of uranium supply for future nuclear energy production. NE initiated a multidisciplinary program with participants from national laboratories, universities, and research institutes to enable technical breakthroughs related to uranium recovery from seawater. The goal is to develop advanced adsorbents to make the seawater uranium recovery technology a cost competitive, viable technology. Under this program, Oak Ridge National Laboratory (ORNL) has developed several novel adsorbents, which enhanced the uranium capacity 4-5 times from the state-of-the art Japanese adsorbents. Uranium exists uniformly at a concentration of ~3.3 ppb in seawater. Because of the vast volume of the oceans, the total estimated amount of uranium in seawater is approximately 1000 times larger than its amount in terrestrial resources. However, due to the low concentration, a significant challenge remains for making the extraction of uranium from seawater a commercially viable alternative technology. The biggest challenge for this technology to overcome to efficiently reduce the extraction cost is to develop adsorbents with increased uranium adsorption capacity. Two major approaches were investigated for synthesizing novel adsorbents with enhanced uranium adsorption capacity. One method utilized conventional radiation induced graft polymerization (RIGP) to synthesize adsorbents on high-surface area trunk fibers and the other method utilized a chemical grafting technique, atom-transfer radical polymerization (ATRP). Both approaches have shown promising uranium extraction

  13. Hydrogen for automotive applications and beyond

    Energy Technology Data Exchange (ETDEWEB)

    Eberle, U. [Adam Opel GmbH, Ruesselsheim (Germany)

    2010-12-30

    The energy storage system is of decisive importance for all types of electric vehicles, in contrast to the case of vehicles powered by a conventional fossil fuel or bio-fuel based internal combustion engine. Two major alternatives exist and need to be discussed: on the one hand, there is the possibility of electrical energy storage using batteries, whilst on the other hand there is the storage of energy in chemical form as hydrogen and the application of a fuel cell as energy converter. Considering the latter concept, hydrogen is a promising energy carrier in future energy systems. However, storage of hydrogen is a substantial challenge, especially for applications in vehicles with fuel cells that use proton-exchange membranes (PEMs). Different methods for hydrogen storage are discussed, including high-pressure and cryogenic-liquid storage, adsorptive storage on high-surface-area adsorbents, chemical storage in metal hydrides and complex hydrides, and storage in boranes. For the latter chemical solutions, reversible options and hydrolytic release of hydrogen with off-board regeneration are both possible. Reforming of liquid hydrogen-containing compounds is also a possible means of hydrogen generation. The advantages and disadvantages of the different systems are compared. (orig.)

  14. Hydrogen adsorption in carbon nanostructures compared

    International Nuclear Information System (INIS)

    Schimmel, H.G.; Nijkamp, G.; Kearley, G.J.; Rivera, A.; Jong, K.P. de; Mulder, F.M.

    2004-01-01

    Recent reports continue to suggest high hydrogen storage capacities for some carbon nanostructures due to a stronger interaction between hydrogen and carbon. Here the interaction of hydrogen with activated charcoal, carbon nanofibers, single walled carbon nanotubes (SWNT), and electron beam 'opened' SWNT are compared and shown to be similar. The storage capacity below 77 K of these materials correlates with the surface area of the material with the activated charcoal having the largest. SWNT and 'opened' SWNT have a relatively low accessible surface area due to bundling of the tubes. Pressure-temperature curves give the interaction potential, which was found to be ∼580 K or 50 meV in all samples, leading to significant adsorption below ∼50 K. Using the inelastic neutron scattering signal associated with rotation of the hydrogen molecule as a sensitive probe for the surroundings of the molecule, no difference was found between the hydrogen molecules adsorbed in the investigated materials. These combined spectroscopic and macroscopic results show that SWNT, nanofibers and activated carbons store molecular hydrogen due to their graphitic nature and not because they possess special morphologies. Results from a density functional theory computer calculation suggest molecular hydrogen bonding to an aromatic C-C bond of graphite, irrespective of the surface morphology farther away

  15. WGS-Adsorbent Reaction Studies at Laboratory Scale

    International Nuclear Information System (INIS)

    Marano, M.; Torreiro, Y.

    2014-01-01

    This document reports the most significant results obtained during the experimental work performed under task WGS adsorbent experimental studies within CAPHIGAS project (National Research Plan 2008-2011, ref: ENE2009-08002). The behavior of the binary adsorbent-catalyst system which will be used in the hybrid system is described in this document. Main results reported here were used during the design and development of the hybrid system adsorbent catalyst- membrane proposed in the CAPHIGAS project. The influence of main operating parameters and the optimized volume ratio adsorbent-catalyst are also presented in this report. (Author)

  16. Neutralization of Rubidium Adsorbate Electric Fields by Electron Attachment

    Energy Technology Data Exchange (ETDEWEB)

    Sedlacek, J. A. [Univ. of Oklahoma, Norman, OK (United States); Kim, E. [Univ. of Nevada, Las Vegas, NV (United States); Rittenhouse, S. T. [Western Washington Univ., Bellingham, WA (United States); US Naval Academy, Annapolis, MD (United States); Weck, Philippe F [Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Sadeghpour, H. R. [Harvard-Smithsonian Center for Astrophysics, Cambridge, MA (United States); Shaffer, J. P. [Univ. of Oklahoma, Norman, OK (United States)

    2015-10-01

    We investigate the (0001) surface of single crystal quartz with a submonolayer of Rb adsorbates. Using Rydberg atom electromagnetically induced transparency, we investigate the electric elds resulting from Rb adsorbed on the quartz surface, and measure the activation energy of the Rb adsorbates. We show that the Rb induces a negative electron affnity (NEA) on the quartz surface. The NEA surface allows for low energy electrons to bind to the surface and cancel the electric eld from the Rb adsorbates. Our results have implications for integrating Rydberg atoms into hybrid quantum systems and the fundamental study of atom-surface interactions, as well as applications for electrons bound to a 2D surface.

  17. Interaction of hydrogen and oxygen with continuous or granular films of palladium

    Energy Technology Data Exchange (ETDEWEB)

    Mikhalenko, I.I.; Prokopov, A.M.; Yagodovskii, V.D.

    1986-03-01

    The authors use desorption and conductometric methods in establishing the existence of three species of adsorbed hydrogen on continuous Pd films and two species on Pd films with a granular structure. Preoxidation of the surface of the continuous films does not affect the rate or kinetic order of hydrogen sorption; oxidation/reduction treatment changes these parameters, but the magnitude of Edes of hydrogen remains unchanged.

  18. Resonance studies of H atoms adsorbed on frozen H2 surfaces

    International Nuclear Information System (INIS)

    Crampton, S.B.

    1980-01-01

    Observations are reported of the ground state hyperfine resonance of hydrogen atoms stored in a 5 cm. diameter bottle coated with frozen molecular hydrogen. Dephasing of the hyperfine resonance while the atoms are adsorbed produces frequency shifts which vary by a factor of two over the temperature range 3.7 K to 4.6 K and radiative decay rates which vary by a factor of five over this range. The magnitudes and temperature dependences of the frequency shifts and decay rates are consistent with a non-uniform distribution of surface adsorption energies with mean about 38(8) K, in agreement with theoretical estimates for a smooth surface. Extrapolation of the 30 nanosec. mean adsorption times at 4.2 K predicts very long adsorption times for H on H 2 below 1 K. Studies of level population recovery rates provide evidence for surface electron spin exchange collisions between adsorbed atoms with collision duration long compared to the hyperfine period, suggesting that the atoms are partially mobile on the surface. The lowest rates observed for level population recovery set a lower limit of about 500 atom-surface collisions at 4.2 K without recombination

  19. Development of Hydrogen Education Programs for Government Officials

    Energy Technology Data Exchange (ETDEWEB)

    Baxter, Shannon [South Carolina Hydrogen and Fuel Cell Alliance, Columbia, SC (United States); Keller, Russ [Advanced Technology International, Cedarburg, WI (United States)

    2016-03-08

    1. Subcontractor/Technical Subject Matter Expert (Tasks 1-3) 2. Technical lead for LFG cleanup and hydrogen production systems Support for Feasibility Study 3. Technical Lead for Feasibility Study Coordination of site preparation activities for all project equipment 4. Host site

  20. Theoretical Insight of Physical Adsorption for a Single-Component Adsorbent + Adsorbate System: I. Thermodynamic Property Surfaces

    KAUST Repository

    Chakraborty, Anutosh

    2009-02-17

    Thermodynamic property surfaces for a single-component adsorbent + adsorbate system are derived and developed from the viewpoint of classical thermodynamics, thermodynamic requirements of chemical equilibrium, Gibbs law, and Maxwell relations. They enable us to compute the entropy and enthalpy of the adsorbed phase, the isosteric heat of adsorption, specific heat capacity, and the adsorbed phase volume thoroughly. These equations are very simple and easy to handle for calculating the energetic performances of any adsorption system. We have shown here that the derived thermodynamic formulations fill up the information gap with respect to the state of adsorbed phase to dispel the confusion as to what is the actual state of the adsorbed phase. We have also discussed and established the temperature-entropy diagrams of (i) CaCl 2-in-silica gel + water system for cooling applications, and (ii) activated carbon (Maxsorb III) + methane system for gas storage. © Copyright 2009 American Chemical Society.

  1. Hydrogen Storage Engineering Center of Excellence Metal Hydride Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Motyka, T. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL)

    2014-05-31

    The Hydrogen Storage Engineering Center of Excellence (HSECoE) was established in 2009 by the U.S. Department of Energy (DOE) to advance the development of materials-based hydrogen storage systems for hydrogen-fueled light-duty vehicles. The overall objective of the HSECoE is to develop complete, integrated system concepts that utilize reversible metal hydrides, adsorbents, and chemical hydrogen storage materials through the use of advanced engineering concepts and designs that can simultaneously meet or exceed all the DOE targets. This report describes the activities and accomplishments during Phase 1 of the reversible metal hydride portion of the HSECoE, which lasted 30 months from February 2009 to August 2011. A complete list of all the HSECoE partners can be found later in this report but for the reversible metal hydride portion of the HSECoE work the major contributing organizations to this effort were the United Technology Research Center (UTRC), General Motors (GM), Pacific Northwest National Laboratory (PNNL), the National Renewable Energy Laboratory (NREL) and the Savannah River National Laboratory (SRNL). Specific individuals from these and other institutions that supported this effort and the writing of this report are included in the list of contributors and in the acknowledgement sections of this report. The efforts of the HSECoE are organized into three phases each approximately 2 years in duration. In Phase I, comprehensive system engineering analyses and assessments were made of the three classes of storage media that included development of system level transport and thermal models of alternative conceptual storage configurations to permit detailed comparisons against the DOE performance targets for light-duty vehicles. Phase 1 tasks also included identification and technical justifications for candidate storage media and configurations that should be capable of reaching or exceeding the DOE targets. Phase 2 involved bench-level testing and

  2. Ion exchange/adsorbent pilot plant

    International Nuclear Information System (INIS)

    Anon.

    1982-01-01

    A decontamination of greater than 99% of the actinides and fission products contained in radioactive waste water can be obtained using ion exchange resins. A system for achieving this result is described in this paper. This ion exchange pilot-plant design is the culmination of five years of study of the decontamination of radioactive waste streams by ion exchange resins and other adsorbents at Mound. In order to maintain maximum flexibility of treatments, this pilot-plant design is a conceptual design with specific flows, resins, and column specifications, but with many optional features and no rigid equipment specifications. This flexibility allows the system to be amenable to almost any radioactive waste stream. Very specific designs can be constructed from this conceptual design for the treatment of any specific waste stream. Operating and capital costs are also discussed. 1 figure, 5 tables

  3. Canyon solvent cleaning with solid adsorbents

    International Nuclear Information System (INIS)

    Reif, D.J.

    1987-01-01

    The HM Process at the Savannah River Plant (SRP) uses 7.5% tributyl phosphate in n-paraffin as an extraction solvent. During use, the solvent is altered due to hydrolysis and radiolysis, forming materials that influence product losses, product decontamination, and separation efficiencies. Laboratory studies to improve online solvent cleaning have shown that carbonate washing, although removing residual solvent activity, does not remove binding ligands that hold fission products in the solvent. Treatment of solvent with a solid adsorbent removes binding ligands and significantly improves recycle solvent performance. Both laboratory work defining a full-scale adsorption process and the use of the process to clean HM Process first cycle solvent are presented

  4. Arsenic Remediation by Synthetic and Natural Adsorbents

    Directory of Open Access Journals (Sweden)

    Muhammad Saqaf Jagirani

    2017-06-01

    Full Text Available The contagion of toxic metals in water is a serious environmental and health concern and threatening problem worldwide. Particularly arsenic contamination in ground water has became great dilemma in the earlier decades. With advent in research for arsenic remediation, standard of drinking water is improving and now reduced to few parts per million (ppm level of arsenic in drinking water sources. However, due to continuous enhancement in environmental pollution, remediation techniques are still needed to achieve the drinking water quality standard. Development of novel and economically feasible removal techniques or materials for selective separation of this toxic specie has been the main focus of research. Several arsenic removal techniques, including membrane separation, coagulation, precipitation, anion exchange have been developed. The aim of this article is to review briefly arsenic chemistry and previous and current available technologies that have been reported various low-cost adsorbents for arsenic removal.

  5. The condensation of water on adsorbed viruses.

    Science.gov (United States)

    Alonso, José María; Tatti, Francesco; Chuvilin, Andrey; Mam, Keriya; Ondarçuhu, Thierry; Bittner, Alexander M

    2013-11-26

    The wetting and dewetting behavior of biological nanostructures and to a greater degree single molecules is not well-known even though their contact with water is the basis for all biology. Here, we show that environmental electron microscopy (EM) can be applied as a means of imaging the condensation of water onto viruses. We captured the formation of submicrometer water droplets and filaments on single viral particles by environmental EM and by environmental transmission EM. The condensate structures are compatible with capillary condensation between adsorbed virus particles and with known droplet shapes on patterned surfaces. Our results confirm that such droplets exist down to condensation/evaporation cycle as expected from their stability in air and water. Moreover we developed procedures that overcome problems of beam damage and of resolving structures with a low atomic number.

  6. Applications of core level spectroscopy to adsorbates

    International Nuclear Information System (INIS)

    Nilsson, Anders

    2002-01-01

    In the following review different applications of core-level spectroscopy to atomic and molecular adsorbates will be shown. Core-holes are created through core-level ionization and X-ray absorption processes and the core-hole decays by radiant and non-radiant processes. This forms the basis for X-ray photoelectron spectroscopy, X-ray absorption spectroscopy, Auger electron spectroscopy and X-ray emission spectroscopy. We will demonstrate how we can use the different methods to obtain information about the chemical state, local geometric structure, nature of chemical bonding and dynamics in electron transfer processes. The adsorption of N 2 and CO on Ni(100) will be used as prototype systems for chemisorption while N 2 on graphite and Ar on Pt for physisorption

  7. In vitro hydroxyapatite adsorbed salivary proteins

    International Nuclear Information System (INIS)

    Vitorino, Rui; Lobo, Maria Joao C.; Duarte, Jose; Ferrer-Correia, Antonio J.; Tomer, Kenneth B.; Dubin, Joshua R.; Domingues, Pedro M.; Amado, Francisco M.L.

    2004-01-01

    In spite of the present knowledge about saliva components and their respective functions, the mechanism(s) of pellicle and dental plaque formation have hitherto remained obscure. This has prompted recent efforts on in vitro studies using hydroxyapatite (HA) as an enamel model. In the present study salivary proteins adsorbed to HA were extracted with TFA and EDTA and resolved by 2D electrophoresis over a pH range between 3 and 10, digested, and then analysed by MALDI-TOF/TOF mass spectrometry and tandem mass spectrometry. Nineteen different proteins were identified using automated MS and MS/MS data acquisition. Among them, cystatins, amylase, carbonic anhydrase, and calgranulin B, were identified

  8. Biodegradation of bacterial polysaccharides adsorbed on montmorillonite

    International Nuclear Information System (INIS)

    Guckert, A.; Tok, H.H.; Jacquin, F.

    1977-01-01

    In this research, by means of a model, a study was made of the biodegradation of microbial organic compounds adsorbed on clays, with a parallel experiment on Fontainebleau sand serving as the control. During incubation the three classes of organic matter ( 14 C-labelled glucose, 14 C-labelled polysaccharides and 14 C-labelled microbial cells) mineralize more actively in the presence of sand than in the presence of clay, since the latter provides protection against biodegradation. Mineralization of the adsorbed organic compounds, however, is marked by clear-cut differences after three weeks - glucose (55%)>polysaccharides (43%)>microbial organisms (7.3%). After incubation, chemical extraction of the organo-mineral complexes by alkaline solvents shows only water-soluble and alkali-soluble products in the case of sand; conversely, in that of montmorillonite the bulk of the 14 C was found in the non-extractable fraction or humin (18.1% of the initial 14 C for glucose, 27.3% for the polysaccharides, and 67.6% for the microbial organisms). A second incubation carried out after a phase in which there was drying and remoistening of the organo-mineral complexes, brings to light the important part played by climatic alternations during the biodegradation process. A new mineralization phase is observed, affecting more the bacterial organisms (14.1%) than the polysaccharides (6.3%), with the glucose-base complexes occupying an intermediate position (11.2%). The chemical fractioning of the organo-mineral complexes following re-incubation shows the stability of 14 C in humin very clearly, especially in the case of polysaccharides, where the mineralization phase relates primarily to the products extractable with alkalis. (author)

  9. Hydrogen storage - are we making progress?

    International Nuclear Information System (INIS)

    Blair, L.; Milliken, J.; Satyapal, S.

    2004-01-01

    'Full text:' The efficient storage of hydrogen in compact, lightweight systems that allow greater than 300-mile range has been identified as one of the major technical challenges facing the practical commercialization of fuel cell power systems for light-duty vehicles. Following the hydrogen vision announced by President Bush in his 2003 State of the Union address, the U.S. Department of Energy issued a Grand Challenge, soliciting ideas from universities, national laboratories, and industry. DOE's National Hydrogen Storage Project, an aggressive and innovative research program focused on materials R and D, will be launched in Fiscal Year 2005. An intensive effort is also underway in the private sector, both in the U.S. and abroad, to meet the challenging on-board hydrogen storage requirements. A historical perspective of hydrogen storage research and development will be provided and the current DOE technical targets for hydrogen storage systems will be discussed. The state-of-the-art in hydrogen storage will be summarized and recent progress assessed. Finally future research directions and areas of technical emphasis will be described. (author)

  10. Hydrogen bonding-mediated dehydrogenation in the ammonia borane combined graphene oxide systems

    Science.gov (United States)

    Kuang, Anlong; Liu, Taijuan; Kuang, Minquan; Yang, Ruifeng; Huang, Rui; Wang, Guangzhao; Yuan, Hongkuan; Chen, Hong; Yang, Xiaolan

    2018-03-01

    The dehydrogenation of ammonia borane (AB) adsorbed on three different graphene oxide (GO) sheets is investigated within the ab initio density functional theory. The energy barriers to direct combination the hydrogens of hydroxyl groups and the hydridic hydrogens of AB to release H2 are relatively high, indicating that the process is energetically unfavorable. Our theoretical study demonstrates that the dehydrogenation mechanism of the AB-GO systems has undergone two critical steps, first, there is the formation of the hydrogen bond (O-H-O) between two hydroxyl groups, and then, the hydrogen bond further react with the hydridic hydrogens of AB to release H2 with low reaction barriers.

  11. Understanding Trends in Catalytic Activity: The Effect of Adsorbate-Adsorbate Interactions for CO Oxidation Over Transition Metals

    DEFF Research Database (Denmark)

    Grabow, Lars; Larsen, Britt Hvolbæk; Nørskov, Jens Kehlet

    2010-01-01

    Using high temperature CO oxidation as the example, trends in the reactivity of transition metals are discussed on the basis of density functional theory (DFT) calculations. Volcano type relations between the catalytic rate and adsorption energies of important intermediates are introduced...... and the effect of adsorbate-adsorbate interaction on the trends is discussed. We find that adsorbate-adsorbate interactions significantly increase the activity of strong binding metals (left side of the volcano) but the interactions do not change the relative activity of different metals and have a very small...... influence on the position of the top of the volcano, that is, on which metal is the best catalyst....

  12. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimize the management of the Technical Network (TN), to ease the understanding and purpose of devices connected to the TN, and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive email notifications from IT/CS asking them to add the corresponding information in the network database. Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  13. Technical Network

    CERN Multimedia

    2007-01-01

    In order to optimise the management of the Technical Network (TN), to facilitate understanding of the purpose of devices connected to the TN and to improve security incident handling, the Technical Network Administrators and the CNIC WG have asked IT/CS to verify the "description" and "tag" fields of devices connected to the TN. Therefore, persons responsible for systems connected to the TN will receive e-mails from IT/CS asking them to add the corresponding information in the network database at "network-cern-ch". Thank you very much for your cooperation. The Technical Network Administrators & the CNIC WG

  14. Facile preparation of highly hydrophilic, recyclable high-performance polyimide adsorbents for the removal of heavy metal ions

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Jieyang; Zheng, Yaxin; Luo, Longbo; Feng, Yan [State Key Laboratory of Polymer Material and Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065 (China); Zhang, Chaoliang [State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University, Chengdu 610041 (China); Wang, Xu, E-mail: wx19861027@163.com [State Key Laboratory of Polymer Material and Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065 (China); Liu, Xiangyang, E-mail: lxy6912@sina.com [State Key Laboratory of Polymer Material and Engineering, College of Polymer Science and Engineering, Sichuan University, Chengdu 610065 (China)

    2016-04-05

    Highlights: • High-performance polyimide was used as heavy metal adsorbents. • The contradiction between hydrophilicity and high performance of PI was solved. • Adsorption amount for Cu{sup 2+} of PI/silica was 77 times higher than that of PI. • The adsorption ability remained steady for more than 50 recycling processes. - Abstract: To obtain high-performance adsorbents that combine excellent adsorption ability, thermal stability, service life and recycling ability, polyimide (PI)/silica powders were prepared via a facile one-pot coprecipitation process. A benzimidazole unit was introduced into the PI backbone as the adsorption site. The benzimidazole unit induced more hydroxyls onto the silica, which provided hydrophilic sites for access by heavy metal ions. By comprehensively analyzing the effect of hydrophilcity, agglomeration, silica polycondensation, specific surface area and PI crystallinity, 10% was demonstrated to be the most proper feed silica content. The equilibrium adsorption amount (Q{sub e}) for Cu{sup 2+} of PI/silica adsorbents was 77 times higher than that of pure PI. Hydrogen chloride (HCl) was used as a desorbent for heavy metal ions and could be decomplexed with benzimidazole unit at around 300 °C, which was lower than the glass transition temperature of PI. The complexation and decomplexation process of HCl made PI/silica adsorbents recyclable, and the adsorption ability remained steady for more than 50 recycling processes. As PI/silica adsorbents possess excellent thermal stability, chemical resistance and radiation resistance and hydrophilicity, they have potential as superior recyclable adsorbents for collecting heavy metal ions from waste water in extreme environments.

  15. Metastable hydrogen

    International Nuclear Information System (INIS)

    Dose, V.

    1982-01-01

    This paper deals with the basic physical properties of the metastable 2 2 sub(1/2) state of atomic hydrogen. Applications relying on its special properties, including measurement of the Lamb shift, production of spin-polarized protons and the measurement of molecular electric moments, are discussed. (author)

  16. Extraction of uranium from sea water with the granular composite adsorbent by using the fixed bed

    International Nuclear Information System (INIS)

    Katoh, Shunsaku; Sakane, Kohji; Hirotsu, Takahiro; Fujii, Ayako; Kitamura, Takao

    1981-01-01

    To clarify the technical problems existing in the extraction process of uranium from sea water, uranium was extracted from natural sea water, with the granulated C-Ti-OH composite adsorbent. The adsorption of uranium from sea water was carried out by using the fixed bed that had been designed in our laboratory. The uranium recovery from the sea water was 13.9% in the adsorption process of 56 d. The adsorbed uranium was eluted from the adsorbent with 0.5 N NaHCO 3 -0.5N Na 2 CO 3 soln. at 70 0 C. The elution recovery was 97.4% for 35 h. The uranium contained in the eluate was concentrated twenty times as much as in the anion exchange process, and then 100 times in the solvent extraction process with oxine-chloroform and TOA-kerosene. About 0.7 g of yellow cake was prepared from natural sea water, and it was identified to be pure 2UO 2 .NH 3 .3H 2 O by X-ray diffraction method and X-ray fluorometry. (author)

  17. Industrial view of Hydrogen Energy

    International Nuclear Information System (INIS)

    Francois Jackow

    2006-01-01

    Industrial Gases Companies have been mastering Hydrogen production, distribution, safe handling and applications for several decades for a wide range of gas applications. This unique industrial background positioned these companies to play a key role in the emerging Hydrogen Energy market, which can rely, at early stage of development, on already existing infrastructure, logistics and technical know-how. Nevertheless, it is important to acknowledge that Hydrogen Energy raised specific challenges which are not totally addressed by industrial gas activities. The main difference is obviously in the final customer profile, which differs significantly from the qualified professional our industry is used to serve. A non professional end-user, operating with Hydrogen at home or on board of his family car, has to be served with intrinsically safe and user-friendly solutions that exceed by far the industrial specifications already in place. Another significant challenge is that we will need breakthroughs both in terms of products and infrastructure, with development time frame that may require several decades. The aim of this presentation is to review how a company like Air Liquide, worldwide leader already operating more than 200 large hydrogen production sites, is approaching this new Hydrogen Energy market, all along the complete supply chain from production to end-users. Our contributions to the analysis, understanding and deployment of this new Energy market, will be illustrated by the presentation of Air Liquide internal development's as well as our participation in several national and European projects. (author)

  18. Industrial implications of hydrogen

    International Nuclear Information System (INIS)

    Pressouyre, G.M.

    1982-01-01

    Two major industrial implications of hydrogen are examined: problems related to the effect of hydrogen on materials properties (hydrogen embrittlement), and problems related to the use and production of hydrogen as a future energy vector [fr

  19. A nuclear standard high-efficiency adsorber for iodine

    International Nuclear Information System (INIS)

    Wang Jianmin; Qian Yinge

    1988-08-01

    The structure of a nuclear standard high-efficiency adsorber, adsorbent and its performance are introduced. The performance and structure were compared with the same kind product of other firms. The results show that the leakage rate is less than 0.005%

  20. Comparative evaluation of selected starches as adsorbent for Thin ...

    African Journals Online (AJOL)

    The most commonly used is silica gel which is an inorganic adsorbent. Organic substances like cellulose, polyethylene are also used. All these are imported into Nigeria and are unhealthy for economic policies. Most commonly used adsorbent may not be easy to produce locally, but starch, which is a very common product, ...

  1. Synthesis and properties of porous zeolite aluminosilicate adsorbents

    International Nuclear Information System (INIS)

    Shilina, A.S.; Milinchuk, V.K.; Burukhin, S.B.; Gordienko, A.B.

    2015-01-01

    Environmentally safe non-energy-intensive methods of the synthesis have been developed and the properties of solid inorganic nanostructured zeolite-like adsorbents of a broad spectrum have been studied. The sorption capacities of the adsorbents with respect to various components of water pollution have been determined [ru

  2. Development of ultrafiltration and inorganic adsorbents: January--March 1977

    International Nuclear Information System (INIS)

    Koenst, J.W. Jr.

    1977-01-01

    Ultrafiltration media with and without the assistance of bone char filters were evaluated to determine their effectiveness in removing radionuclides from contaminated solutions. Precipitants, resin, adsorbents, and inorganic adsorbents were studied to determine their effectiveness in decontaminating solutions. A study of the effects of radiation on ultrafiltration media was initiated. An ultrafiltration media pilot plant was ordered and is being installed

  3. Friction and diffusion dynamics of adsorbates at surfaces

    NARCIS (Netherlands)

    Fusco, C.

    2005-01-01

    A theoretical study of the motion of adsorbates (e. g. atoms, molecules or clusters) on solid surfaces is presented, with a focus on surface diffusion and atomic-scale friction. These two phenomena are inextricably linked, because when an atomic or molecular adsorbate diffuses, or is pulled, it

  4. Mixed-matrix membrane adsorbers for protein separation

    NARCIS (Netherlands)

    Avramescu, M.E.; Borneman, Z.; Wessling, M.

    2003-01-01

    The separation of two similarly sized proteins, bovine serum albumin (BSA) and bovine hemoglobin (Hb) was carried out using a new type of ion-exchange mixed-matrix adsorber membranes. The adsorber membranes were prepared by incorporation of various types of Lewatit ion-exchange resins into an

  5. Single bank NOx adsorber for heavy duty diesel engines

    NARCIS (Netherlands)

    Genderen, M. van; Aken, M.G. van

    2003-01-01

    In a NOx adsorber programme the feasibility for applying this technology to heavy duty diesel engines was investigated. After modelling and simulations for realising best λ < 1 engine conditions a platform was build which was used to obtain good NOx adsorber regeneration settings in a number of

  6. Multiply Surface-Functionalized Nanoporous Carbon for Vehicular Hydrogen Storage

    Energy Technology Data Exchange (ETDEWEB)

    Pfeifer, Peter [Univ. of Missouri, Columbia, MO (United States). Dept. of Physics; Gillespie, Andrew [Univ. of Missouri, Columbia, MO (United States). Dept. of Physics; Stalla, David [Univ. of Missouri, Columbia, MO (United States). Dept. of Physics; Dohnke, Elmar [Univ. of Missouri, Columbia, MO (United States). Dept. of Physics

    2017-02-20

    The purpose of the project “Multiply Surface-Functionalized Nanoporous Carbon for Vehicular Hydrogen Storage” is the development of materials that store hydrogen (H2) by adsorption in quantities and at conditions that outperform current compressed-gas H2 storage systems for electric power generation from hydrogen fuel cells (HFCs). Prominent areas of interest for HFCs are light-duty vehicles (“hydrogen cars”) and replacement of batteries with HFC systems in a wide spectrum of applications, ranging from forklifts to unmanned areal vehicles to portable power sources. State-of-the-art compressed H2 tanks operate at pressures between 350 and 700 bar at ambient temperature and store 3-4 percent of H2 by weight (wt%) and less than 25 grams of H2 per liter (g/L) of tank volume. Thus, the purpose of the project is to engineer adsorbents that achieve storage capacities better than compressed H2 at pressures less than 350 bar. Adsorption holds H2 molecules as a high-density film on the surface of a solid at low pressure, by virtue of attractive surface-gas interactions. At a given pressure, the density of the adsorbed film is the higher the stronger the binding of the molecules to the surface is (high binding energies). Thus, critical for high storage capacities are high surface areas, high binding energies, and low void fractions (high void fractions, such as in interstitial space between adsorbent particles, “waste” storage volume by holding hydrogen as non-adsorbed gas). Coexistence of high surface area and low void fraction makes the ideal adsorbent a nanoporous monolith, with pores wide enough to hold high-density hydrogen films, narrow enough to minimize storage as non-adsorbed gas, and thin walls between pores to minimize the volume occupied by solid instead of hydrogen. A monolith can be machined to fit into a rectangular tank (low pressure, conformable tank), cylindrical tank

  7. Ionogenic adsorbents based on local raw materials for radiation protection

    International Nuclear Information System (INIS)

    Isobaev, M.D.; Davlatnazarova, M.; Turdialiev, M.Z.; Abdullayev, T.H.; Pulatov, E.H.

    2012-01-01

    The successful management of uranium wastes and creating the conditions for effective rehabilitation activities require special adsorbents capable of holding on the surface complexes, including radioactive elements. Currently tested and have shown promising synthetic adsorbents based pitted apricot fruits and other fruit plants. This report presents data for the establishment of ionic type available adsorbents based on Tajikistan coal. As the base for the creation of this type of adsorbent were taken the coal of the 'Ziddi' deposits. As follows from our data on the chemical composition, the studied coals contain more than 20% of the ash. According to the available literature theses ashes contains various minerals compositions that can form the adsorbent's active surface. Thus, the model for this type of activated carbon can serve as a mixture of zeolite, ion exchange resins and activated carbon itself.

  8. Processing method and device for iodine adsorbing material

    International Nuclear Information System (INIS)

    Watanabe, Shin-ichi; Shiga, Reiko.

    1997-01-01

    An iodine adsorbing material adsorbing silver compounds is reacted with a reducing gas, so that the silver compounds are converted to metal silver and stored. Then, the silver compounds are not melted or recrystallized even under a highly humid condition, accordingly, peeling of the adsorbed materials from a carrier can be prevented, and the iodine adsorbing material can be stored stably. Since the device is disposed in an off gas line for discharging off gases from a nuclear power facility, the iodine adsorbing material formed by depositing silver halides to the carrier is contained, and a reducing or oxidizing gas is supplied to the vessel as required, and silver halides can be converted to metal silver or the metal silver can be returned to silver halide. (T.M.)

  9. Nano-sized Adsorbate Structure Formation in Anisotropic Multilayer System

    Science.gov (United States)

    Kharchenko, Vasyl O.; Kharchenko, Dmitrii O.; Yanovsky, Vladimir V.

    2017-05-01

    In this article, we study dynamics of adsorbate island formation in a model plasma-condensate system numerically. We derive the generalized reaction-diffusion model for adsorptive multilayer system by taking into account anisotropy in transfer of adatoms between neighbor layers induced by electric field. It will be found that with an increase in the electric field strength, a structural transformation from nano-holes inside adsorbate matrix toward separated nano-sized adsorbate islands on a substrate is realized. Dynamics of adsorbate island sizes and corresponding distributions are analyzed in detail. This study provides an insight into details of self-organization of adatoms into nano-sized adsorbate islands in anisotropic multilayer plasma-condensate systems.

  10. Noble gas separation with the use of inorganic adsorbents

    International Nuclear Information System (INIS)

    Pence, D.T.; Chou, C.C.; Christian, J.D.; Paplawsky, W.J.

    1979-01-01

    A noble gas separation process is proposed for application to airborne nuclear fuel reprocessing plant effluents. The process involves the use of inorganic adsorbents for the removal of contaminant gases and noble gas separation through selective adsorption. Water and carbon dioxide are removed with selected zeolites that do not appreciably adsorb the noble gases. Xenon is essentially quantitatively removed with a specially developed adsorbent using conventional adsorption-desorption techniques. Oxygen is removed to low ppM levels by the use of a rapid cycle adsorption technique on a special adsorbent leaving a krypton-nitrogen mixture. Krypton is separated from nitrogen with a special adsorbent operated at about -80 0 C. Because the separation process does not require high pressures and oxygen is readily removed to sufficiently limit ozone formation to insignificant levels, appreciable capital and operating cost savings with this process are possible compared with other proposed processes. In addition, the proposed process is safer to operate

  11. Flow boundary conditions for chain-end adsorbing polymer blends.

    Science.gov (United States)

    Zhou, Xin; Andrienko, Denis; Delle Site, Luigi; Kremer, Kurt

    2005-09-08

    Using the phenol-terminated polycarbonate blend as an example, we demonstrate that the hydrodynamic boundary conditions for a flow of an adsorbing polymer melt are extremely sensitive to the structure of the epitaxial layer. Under shear, the adsorbed parts (chain ends) of the polymer melt move along the equipotential lines of the surface potential whereas the adsorbed additives serve as the surface defects. In response to the increase of the number of the adsorbed additives the surface layer becomes thinner and solidifies. This results in a gradual transition from the slip to the no-slip boundary condition for the melt flow, with a nonmonotonic dependence of the slip length on the surface concentration of the adsorbed ends.

  12. Hydrogen Storage and Production Project

    Energy Technology Data Exchange (ETDEWEB)

    Bhattacharyya, Abhijit [Univ. of Arkansas, Little Rock, AR (United States); Biris, A. S. [Univ. of Arkansas, Little Rock, AR (United States); Mazumder, M. K. [Univ. of Arkansas, Little Rock, AR (United States); Karabacak, T. [Univ. of Arkansas, Little Rock, AR (United States); Kannarpady, Ganesh [Univ. of Arkansas, Little Rock, AR (United States); Sharma, R. [Univ. of Arkansas, Little Rock, AR (United States)

    2011-07-31

    This is the final technical report. This report is a summary of the project. The goal of our project is to improve solar-to-hydrogen generation efficiency of the PhotoElectroChemical (PEC) conversion process by developing photoanodes with high absorption efficiency in the visible region of the solar radiation spectrum and to increase photo-corrosion resistance of the electrode for generating hydrogen from water. To meet this goal, we synthesized nanostructured heterogeneous semiconducting photoanodes with a higher light absorption efficiency compared to that of TiO2 and used a corrosion protective layer of TiO2. While the advantages of photoelectrochemical (PEC) production of hydrogen have not yet been realized, the recent developments show emergence of new nanostructural designs of photoanodes and choices of materials with significant gains in photoconversion efficiency.

  13. Electric hydrogen recombiner special tests

    International Nuclear Information System (INIS)

    Wilson, J.F.

    1975-12-01

    Westinghouse has produced an electric hydrogen recombiner to control hydrogen levels in reactor containments following a postulated loss-of-coolant accident. The recombiner underwent extensive testing for NRC qualification (see WCAP 7709-L and Supplements 1, 2, 3, 4). As a result, WCAP 7709-L and Supplements 1, 2, 3, and 4 have been accepted by the NRC for reference in applications not committed to IEEE-323-1974. Supplement 5 and the next supplement will demonstrate conformance to IEEE-323-1974. This supplement describes additional tests, beyond those necessary to qualify the system, which will be referenced in supplement 6. Each test has demonstrated a considerable margin of safety over required performance. Concurrently, the test results increased the fund of technical information on the electric hydrogen recombiner

  14. Bioavailability of Carbon Nanomaterial-Adsorbed Polycyclic Aromatic Hydrocarbons to Pimphales promelas: Influence of Adsorbate Molecular Size and Configuration.

    Science.gov (United States)

    Linard, Erica N; Apul, Onur G; Karanfil, Tanju; van den Hurk, Peter; Klaine, Stephen J

    2017-08-15

    Despite carbon nanomaterials' (CNMs) potential to alter the bioavailability of adsorbed contaminants, information characterizing the relationship between adsorption behavior and bioavailability of CNM-adsorbed contaminants is still limited. To investigate the influence of CNM morphology and organic contaminant (OC) physicochemical properties on this relationship, adsorption isotherms were generated for a suite of polycyclic aromatic hydrocarbons (PAHs) on multiwalled carbon nanotubes (MWCNTs) and exfoliated graphene (GN) in conjunction with determining the bioavailability of the adsorbed PAHs to Pimphales promelas using bile analysis via fluorescence spectroscopy. Although it appeared that GN adsorbed PAHs indiscriminately compared to MWCNTs, the subsequent bioavailability of GN-adsorbed PAHs was more sensitive to PAH morphology than MWCNTs. GN was effective at reducing bioavailability of linear PAHs by ∼70%, but had little impact on angular PAHs. MWCNTs were sensitive to molecular size, where bioavailability of two-ringed naphthalene was reduced by ∼80%, while bioavailability of the larger PAHs was reduced by less than 50%. Furthermore, the reduction in bioavailability of CNM-adsorbed PAHs was negatively correlated with the amount of CNM surface area covered by the adsorbed-PAHs. This study shows that the variability in bioavailability of CNM-adsorbed PAHs is largely driven by PAH size, configuration and surface area coverage.

  15. Milestone Report - Complete New Adsorbent Materials for Marine Testing to Demonstrate 4.5 g-U/kg Adsorbent

    Energy Technology Data Exchange (ETDEWEB)

    Janke, Christopher James [ORNL; Das, Sadananda [ORNL; Oyola, Yatsandra [ORNL; Mayes, Richard T. [ORNL; Saito, Tomonori [ORNL; Brown, Suree [ORNL; Gill, Gary [PNNL; Kuo, Li-Jung [PNNL; Wood, Jordana [PNNL

    2014-08-01

    This report describes work on the successful completion of Milestone M2FT-14OR03100115 (8/20/2014) entitled, “Complete new adsorbent materials for marine testing to demonstrate 4.5 g-U/kg adsorbent”. This effort is part of the Seawater Uranium Recovery Program, sponsored by the U.S. Department of Energy, Office of Nuclear Energy, and involved the development of new adsorbent materials at the Oak Ridge National Laboratory (ORNL) and marine testing at the Pacific Northwest National Laboratory (PNNL). ORNL has recently developed two new families of fiber adsorbents that have demonstrated uranium adsorption capacities greater than 4.5 g-U/kg adsorbent after marine testing at PNNL. One adsorbent was synthesized by radiation-induced graft polymerization of itaconic acid and acrylonitrile onto high surface area polyethylene fibers followed by amidoximation and base conditioning. This fiber showed a capacity of 4.6 g-U/kg adsorbent in marine testing at PNNL. The second adsorbent was prepared by atom-transfer radical polymerization of t-butyl acrylate and acrylonitrile onto halide-functionalized round fibers followed by amidoximation and base hydrolysis. This fiber demonstrated uranium adsorption capacity of 5.4 g-U/kg adsorbent in marine testing at PNNL.

  16. Effect of controlled deactivation on the thermochemical characteristics of hydrogen adsorption on skeletal nickel from sodium hydroxide-water solutions

    Science.gov (United States)

    Prozorov, D. A.; Lukin, M. V.; Ulitin, M. V.

    2013-04-01

    Differential heats of adsorption in a wide range of surface coverage and maximum amounts of adsorbed hydrogen are determined by adsorption calorimetry on partially deactivated skeletal nickel from aqueous solutions of sodium hydroxide. The effect of the composition of solutions on the values of limiting adsorption and adsorption equilibria of individual forms of hydrogen is shown.

  17. Hydrogen: the future of the car

    International Nuclear Information System (INIS)

    Beuzit, P.

    2007-01-01

    With the end of the petroleum resources, the hydrogen offers interesting perspectives in the context of a sustainable development. The authors analyze the challenges of the hydrogen vehicle: the substitution fuels, the technical interior design, the cost of this evolution, the impacts on the world energy map and the part played by the France and the automobile sector in this evolution. (A.L.B.)

  18. Formic Acid as a Hydrogen Energy Carrier

    KAUST Repository

    Eppinger, Jö rg; Huang, Kuo-Wei

    2016-01-01

    The high volumetric capacity (S3 g H-2/L) and its low toxicity and flammability under ambient conditions make formic acid a promising hydrogen energy carrier. Particularly, in the past decade, significant advancements have been achieved in catalyst development for selective hydrogen generation from formic acid. This Perspective highlights the advantages of this approach with discussions focused on potential applications in the transportation sector together with analysis of technical requirements, limitations, and costs.

  19. Formic Acid as a Hydrogen Energy Carrier

    KAUST Repository

    Eppinger, Jorg

    2016-12-15

    The high volumetric capacity (S3 g H-2/L) and its low toxicity and flammability under ambient conditions make formic acid a promising hydrogen energy carrier. Particularly, in the past decade, significant advancements have been achieved in catalyst development for selective hydrogen generation from formic acid. This Perspective highlights the advantages of this approach with discussions focused on potential applications in the transportation sector together with analysis of technical requirements, limitations, and costs.

  20. Surface characterization of Ag/Titania adsorbents

    International Nuclear Information System (INIS)

    Samokhvalov, Alexander; Nair, Sachin; Duin, Evert C.; Tatarchuk, Bruce J.

    2010-01-01

    The Ag/Titania adsorbent for selective removal of the desulfurization-refractive polycyclic aromatic sulfur heterocycles (PASHs) from liquid hydrocarbon fuels was prepared, its total and the Ag specific surface area were determined and the surface reaction sites in the sorbent that may be active in the adsorptive selective desulfurization were characterized by several spectroscopic and surface science techniques. The sorbent contains Ag, Ti, O and spurious C on its surface, as by the XPS measurements. Silver is present as an oxide, as judged by the XPS Auger parameter (AP). The complementary electron spin resonance (ESR) spectroscopy confirms that the majority of Ag is present in the diamagnetic Ag 1+ form, with the minor concentration (∼0.1% of total Ag) present as Ag 2+ . The findings by XPS and ESR are confirmed by the XRD, UV-vis spectroscopy and thermodynamic considerations. The supported Ag is highly dispersed on the surface of the titania support, with the particle size of ∼30-60 A depending on Ag content, with an Ag specific surface area of ∼7-14 m 2 /g, vs. the total surface area of ∼114-58 m 2 /g.

  1. Modification of the properties of Pt-Al/sub 2/O/sub 3/ catalysts by hydrogen at high temperatures

    Energy Technology Data Exchange (ETDEWEB)

    Menon, P.G.; Froment, G.F.

    1979-08-01

    Pulse reactor studies were performed on the hydrogenolysis of n-pentane and n-hexane at 400/sup 0/C on two commercial reforming catalysts that contained 0.6 and 0.75% platinum on alumina, respectively, and which were calcined in air at 500/sup 0/C, followed by hydrogen-reduction at 400/sup 0/-600/sup 0/C. On catalysts reduced at 400/sup 0/C, hydrogenolysis was the main reaction; with increasing reducing temperature, hydrogenolysis was suppressed and isomerization selectivity increased; at 550/sup 0/C pretreatment temperature, hydrogenolysis was near zero. This selective catalyst deactivation was reversed by oxidizing the catalyst in air at 500/sup 0/C in a similar manner as previously found for sulfided and chlorided catalysts. Temperature-programed desorption of hydrogen adsorbed at 20/sup 0/-600/sup 0/C revealed that the higher the adsorption temperature, the higher the temperature of the hydrogen desorption peaks: the hydrogen adsorbed below 400/sup 0/C desorbed mainly at 50/sup 0/-300/sup 0/C, but the hydrogen adsorbed at higher temperatures desorbed at 300/sup 0/-500/sup 0/C. Apparently, two types of hydrogen adsorb in the two temperature regions, of which the more strongly adsorbed type inhibits hydrogenolysis but not isomerization.

  2. Hydrogen Adsorption in Zeolite Studied with Sievert and Thermogravimetric Methods

    International Nuclear Information System (INIS)

    Lesnicenoks, P; Sivars, A; Grinberga, L; Kleperis, J

    2012-01-01

    Natural clinoptilolite (mixture from clinoptilolite, quartz and muscovite) is activated with palladium and tested for hydrogen adsorption capability at temperatures RT - 200°C. Thermogravimetric and volumetric methods showed that zeolite activated with palladium (1.25%wt) shows markedly high hydrogen adsorption capacity - up to 3 wt%. Lower amount of adsorbed hydrogen (∼1.5 wt%) was found for raw zeolite and activated with higher amount of palladium sample. Hypothesis is proposed that the heating of zeolite in argon atmosphere forms and activates the pore structure in zeolite material, where hydrogen encapsulation (trapping) is believed to occur when cooling down to room temperature. An effect of catalyst (Pd) on hydrogen sorption capability is explained by spillover phenomena were less-porous fractions of natural clinoptilolite sample (quartz and muscovite) are involved.

  3. Magnetic adsorbent constructed from the loading of amino functionalized Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalates nanoparticle and its tetracycline adsorption removal property study

    Energy Technology Data Exchange (ETDEWEB)

    Ou, Jinzhao; Mei, Mingliang; Xu, Xinxin, E-mail: xuxx@mail.neu.edu.cn

    2016-06-15

    A magnetic polyoxometalates based adsorbent has been synthesized successfully through the loading of amino functionalized Fe{sub 3}O{sub 4} (NH{sub 2}-Fe{sub 3}O{sub 4}) on nanoparticle of a coordination complex modified polyoxometalates (CC/POMNP). FTIR illustrate there exist intense hydrogen bonds between NH{sub 2}-Fe{sub 3}O{sub 4} and CC/POMNP, which keep the stability of this adsorbent. At room temperature, this adsorbent exhibits ferromagnetic character with saturation magnetization of 8.19 emu g{sup −1}, which provides prerequisite for fast magnetic separation. Water treatment experiment illustrates this POM based magnetic adsorbent exhibits high adsorption capacity on tetracycline. The adsorption process can be described well with Temkin model, which illustrates the interaction between adsorbent and tetracycline plays the dominated role in tetracycline removal. The rapid, high efficient tetracycline adsorption ability suggests this POM based magnetic adsorbent exhibits promising prospect in medical and agriculture waste water purification. A magnetic polyoxometalates based adsorbent, which exhibits excellent tetracycline adsorption removal property has been synthesized through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalates - Graphical abstract: A magnetic polyoxometalates based adsorbent, which exhibits excellent tetracycline adsorption removal property has been synthesized through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on coordination complex modified polyoxometalate. Display Omitted - Highlights: • A POM based magnetic adsorbent was fabricated through the loading of NH{sub 2}-Fe{sub 3}O{sub 4} on POM nanoparticle. • This adsorbent possesses excellent tetracycline adsorption property. • Saturation magnetization value of this adsorbent is 8.19 emug−1, which is enough for magnetic separation.

  4. DEVELOPMENT OF DOPED NANOPOROUS CARBONS FOR HYDROGEN STORAGE

    Energy Technology Data Exchange (ETDEWEB)

    Lueking, Angela D.; Li, Qixiu; Badding, John V.; Fonseca, Dania; Gutierrez, Humerto; Sakti, Apurba; Adu, Kofi; Schimmel, Michael

    2010-03-31

    Hydrogen storage materials based on the hydrogen spillover mechanism onto metal-doped nanoporous carbons are studied, in an effort to develop materials that store appreciable hydrogen at ambient temperatures and moderate pressures. We demonstrate that oxidation of the carbon surface can significantly increase the hydrogen uptake of these materials, primarily at low pressure. Trace water present in the system plays a role in the development of active sites, and may further be used as a strategy to increase uptake. Increased surface density of oxygen groups led to a significant enhancement of hydrogen spillover at pressures less than 100 milibar. At 300K, the hydrogen uptake was up to 1.1 wt. % at 100 mbar and increased to 1.4 wt. % at 20 bar. However, only 0.4 wt% of this was desorbable via a pressure reduction at room temperature, and the high lowpressure hydrogen uptake was found only when trace water was present during pretreatment. Although far from DOE hydrogen storage targets, storage at ambient temperature has significant practical advantages oner cryogenic physical adsorbents. The role of trace water in surface modification has significant implications for reproducibility in the field. High-pressure in situ characterization of ideal carbon surfaces in hydrogen suggests re-hybridization is not likely under conditions of practical interest. Advanced characterization is used to probe carbon-hydrogen-metal interactions in a number of systems and new carbon materials have been developed.

  5. Analysis of hydrogen distribution on Mg-Ni alloy surface by scanning electron-stimulated desorption ion microscope (SESDIM)

    International Nuclear Information System (INIS)

    Yamaga, Atsushi; Hibino, Kiyohide; Suzuki, Masanori; Yamada, Masaaki; Tanaka, Kazuhide; Ueda, Kazuyuki

    2008-01-01

    Hydrogen distribution and behavior on a Mg-Ni alloy surface are studied by using a time-of-flight electron-stimulated desorption (TOF-ESD) microscopy and a scanning electron microscope with energy dispersive X-ray spectroscopy (SEM-EDX). The desorbed hydrogen ions are energy-discriminated and distinguished into two characters in the adsorbed states, which belong to Mg 2 Ni grains and the other to oxygen-contaminated Mg phase at the grain boundaries. Adsorbed hydrogen is found to be stable up to 150 deg. C, but becomes thermally unstable around at 200 deg. C

  6. Codes and Standards Technical Team Roadmap

    Energy Technology Data Exchange (ETDEWEB)

    None

    2013-06-01

    The Hydrogen Codes and Standards Tech Team (CSTT) mission is to enable and facilitate the appropriate research, development, & demonstration (RD&D) for the development of safe, performance-based defensible technical codes and standards that support the technology readiness and are appropriate for widespread consumer use of fuel cells and hydrogen-based technologies with commercialization by 2020. Therefore, it is important that the necessary codes and standards be in place no later than 2015.

  7. Mercury adsorption properties of sulfur-impregnated adsorbents

    Science.gov (United States)

    Hsi, N.-C.; Rood, M.J.; Rostam-Abadi, M.; Chen, S.; Chang, R.

    2002-01-01

    Carbonaceous and noncarbonaceous adsorbents were impregnated with elemental sulfur to evaluate the chemical and physical properties of the adsorbents and their equilibrium mercury adsorption capacities. Simulated coal combustion flue gas conditions were used to determine the equilibrium adsorption capacities for Hg0 and HgCl2 gases to better understand how to remove mercury from gas streams generated by coal-fired utility power plants. Sulfur was deposited onto the adsorbents by monolayer surface deposition or volume pore filling. Sulfur impregnation increased the total sulfur content and decreased the total and micropore surface areas and pore volumes for all of the adsorbents tested. Adsorbents with sufficient amounts of active adsorption sites and sufficient microporous structure had mercury adsorption capacities up to 4,509 ??g Hg/g adsorbent. Elemental sulfur, organic sulfur, and sulfate were formed on the adsorbents during sulfur impregnation. Correlations were established with R2>0.92 between the equilibrium Hg0/HgCl2 adsorption capacities and the mass concentrations of elemental and organic sulfur. This result indicates that elemental and organic sulfur are important active adsorption sites for Hg0 and HgCl2.

  8. Hydrogenation of benzaldehyde via electrocatalysis and thermal catalysis on carbon-supported metals

    Energy Technology Data Exchange (ETDEWEB)

    Song, Yang; Sanyal, Udishnu; Pangotra, Dhananjai; Holladay, Jamelyn D.; Camaioni, Donald M.; Gutierrez-Tinoco, Oliver Y.; Lercher, Johannes A.

    2018-03-01

    Abstract Selective reduction of benzaldehyde to benzyl alcohol on C-supported Pt, Rh, Pd, and Ni in aqueous phase was conducted using either directly H2 (thermal catalytic hydrogenation, TCH) or in situ electrocatalytically generated hydrogen (electrocatalytic hydrogenation, ECH). In TCH, the intrinsic activity of the metals at room temperature and 1 bar H2 increased in the sequence Rh/C < Pt/C < Pd/C, while Ni/C is inactive at these conditions due to surface oxidation in the absence of cathodic potential. The reaction follows a Langmuir-Hinshelwood mechanism with the second hydrogen addition to the adsorbed hydrocarbon being the rate-determining step. All tested metals were active in ECH of benzaldehyde, although hydrogenation competes with the hydrogen evolution reaction (HER). The minimum cathodic potentials to obtain appreciable ECH rates were identical to the onset potentials of HER. Above this onset, the relative rates of H reacting to H2 and H addition to the hydrocarbon determines the selectivity to ECH and TCH. Accordingly, the selectivity of the metals towards ECH increases in the order Ni/C < Pt/C < Rh/C < Pd/C. Pd/C shows exceptionally high ECH selectivity due to its surprisingly low HER reactivity under the reaction conditions. Acknowledgements The authors would like to thank the groups of Hubert A. Gasteiger at the Technische Universität München of Jorge Gascon at the Delft University of Technology for advice and valuable discussions. The authors are grateful to Nirala Singh, Erika Ember, Gary Haller, and Philipp Rheinländer for fruitful discussions. We are also grateful to Marianne Hanzlik for TEM measurements and to Xaver Hecht and Martin Neukamm for technical support. Y.S. would like to thank the Chinese Scholarship Council for the financial support. The research described in this paper is part of the Chemical Transformation Initiative at Pacific Northwest National Laboratory (PNNL), conducted under the Laboratory Directed Research and

  9. Nonadiabatic effects on surfaces: Kohn anomaly, electronic damping of adsorbate vibrations, and local heating of single molecules

    International Nuclear Information System (INIS)

    Kroeger, J

    2008-01-01

    Three aspects of electron-phonon coupling at metal surfaces are reviewed. One aspect is the Kohn effect, which describes an anomalous dispersion relation of surface phonons due to quasi-one-dimensional nesting of Fermi surface contours. The combination of electron energy loss spectroscopy and angle-resolved photoelectron spectroscopy allows us to unambiguously characterize Kohn anomaly systems. A second aspect is the nonadiabatic damping of adsorbate vibrations. Characteristic spectroscopic line shapes of vibrational modes allow us to estimate the amount of energy transfer between the vibrational mode and electron-hole pairs. Case studies of a Kohn anomaly and nonadiabatic damping are provided by the hydrogen- and deuterium-covered Mo(110) surface. As a third aspect of interaction between electrons and phonons, local heating of a C 60 molecule adsorbed on Cu(100) and in contact with the tip of a scanning tunnelling microscope is covered

  10. A theoretical study of adsorbate-adsorbate interactions on Ru(0001)

    DEFF Research Database (Denmark)

    Mortensen, Jens Jørgen; Hammer, Bjørk; Nørskov, Jens Kehlet

    1998-01-01

    the barrier for dissociation, whereas S will increase it. The interaction with alkali atoms is mainly of an electrostatic nature. The poisoning by S is due to two kinds of repulsive interactions: a Pauli repulsion and a reduced covalent bond strength between the adsorbate and the surface d-electrons. In order...... to investigate these different interactions in more detail, we look at three different species (N atoms, and terminally bonded N(2) and CO) and use them as probes to study their interaction with two modifier atoms (Na and S). The two modifier atoms have very different properties, which allows us to decouple...

  11. Kinetics, isotope effects, and mechanism for the hydrogenation of carbon monoxide on supported nickel catalysts

    International Nuclear Information System (INIS)

    Mori, T.; Masuda, H.; Imai, H.; Miyamoto, A.; Baba, S.; Murakami, Y.

    1982-01-01

    Kinetics and hydrogen-deuterium isotope effects in the methanation of adsorbed CO molecules on a Ni/SiO 2 catalyst were precisely measured by using pulse surface reaction rate analysis (PSRA). When a CO pulse was injected into flowing hydrogen, it was immediately adsorbed on the catalyst and gradually hydrogenated to CH 4 and H 2 O. The amounts of CH 4 and H 2 O produced by the hydrogenation of the adsorbed CO were determined up to various times, and it was found that CH 4 and H 2 O were produced at the same rate. When O 2 instead of CO was injected, H 2 O was immediately produced. From these results, the rate-determining step of the reaction was found to be C-O bond dissociation of an adsorbed CO molecule or a partially hydrogenated CO species. By PSRA, the rate constant for the C-O bond dissocition process per adsorbed CO molecule (k/sub H/) was determined at various temperatures, and the Arrhenius parameters of the rate constant were obtained. The rate constant in flowing deuterium (k/sub D/) was also determined. it was found that k/sub D/ is considerably larger than k/sub H/, indicating an inverse isotope effect. The average value of k/sub H//k/sub D/ was 0.75. From these results, it was concluded that adsorbed CO is not directly dissociated to surface carbon and oxygen atoms but it is partially hydrogenated before C-O bond dissociation under the conditions of the PSRA experiment. 8 figures

  12. The hydrogen; L'hydrogene

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-07-01

    The hydrogen as an energy system represents nowadays a main challenge (in a scientific, economical and environmental point of view). The physical and chemical characteristics of hydrogen are at first given. Then, the challenges of an hydrogen economy are explained. The different possibilities of hydrogen production are described as well as the distribution systems and the different possibilities of hydrogen storage. Several fuel cells are at last presented: PEMFC, DMFC and SOFC. (O.M.)

  13. Scanning tunneling spectroscopy of Co adsorbates on superconducting Pb nanostructures

    Energy Technology Data Exchange (ETDEWEB)

    Decker, Regis; Caminale, Michael; Oka, Hirofumi; Stepniak, Agnieszka; Leon Vanegas, Augusto A.; Sander, Dirk; Kirschner, Juergen [Max-Planck-Institut fuer Mikrostrukturphysik, Weinberg 2, 06120 Halle (Germany)

    2015-07-01

    Superconductivity in low-dimensional structures has become an active research area. In order to understand the superconducting pairing, long-standing work has been devoted to the pair breaking effect, where magnetic impurities break Cooper pair singlets. We performed scanning tunneling spectroscopy at low temperature on Co adsorbates on superconducting Pb nanoislands. On the Co adsorbates, we observe spectral features in the superconductor's energy gap, which we attribute to magnetic impurity induced bound states, a hallmark of the pair breaking effect. We discuss the response of the superconducting islands to the presence of Co adsorbates.

  14. Cathodic over-potential and hydrogen partial pressure coupling in hydrogen evolution reaction of marine steel under hydrostatic pressure

    International Nuclear Information System (INIS)

    Xiong, X.L.; Zhou, Q.J.; Li, J.X.; Volinsky, Alex A.; Su, Y.J.

    2017-01-01

    Highlights: •Hydrostatic pressure increases the Volmer and the Heyrovsky reactions rates. •Hydrostatic pressure decreases the Tafel reaction rate. •Hydrogen adsorption conditions change with pressure under −1.2 and −1.3 V SSE . •Under −1.2 and −1.3 V SSE , the Heyrovsky reaction dominates the hydrogen recombination. •Under −1.0 and −1.1 V SSE , the Tafel reaction dominates the hydrogen recombination. -- Abstract: A new electrochemical impedance spectroscopy (EIS) model, which considers both the Tafel recombination and the Heyrovsky reaction under permeable boundary conditions, was developed to characterize the kinetic parameters of the hydrogen evolution reaction (HER) under hydrostatic pressure. The effect of the hydrostatic pressure on the kinetic parameters of the HER and the permeation of A514 steel in alkaline solution were measured using potentiodynamic polarization, the Devanathan cell hydrogen permeation, and EIS. The hydrostatic pressure accelerates the Volmer reaction and inhibits the Tafel recombination, which increases the number of adsorbed hydrogen atoms. On the other hand, the pressure accelerates the Heyrovsky reaction, which decreases the amount of adsorbed hydrogen atoms. At 10 to 40 MPa hydrostatic pressure within the −1.0 to −1.1 V SSE cathodic potential region, the HER is controlled by hydrogen partial pressure, and hydrogen adsorption is the Langmuir type. Within the −1.2 to −1.3 V SSE cathodic potential region, the HER is controlled by the potential, and hydrogen adsorption gradually transfers from the Langmuir type to the Temkin type with increasing hydrostatic pressure.

  15. The solar-hydrogen economy: an analysis

    Science.gov (United States)

    Reynolds, Warren D.

    2007-09-01

    The 20th Century was the age of the Petroleum Economy while the 21st Century is certainly the age of the Solar-Hydrogen Economy. The global Solar-Hydrogen Economy that is now emerging follows a different logic. Under this new economic paradigm, new machines and methods are once again being developed while companies are restructuring. The Petroleum Economy will be briefly explored in relation to oil consumption, Hubbert's curve, and oil reserves with emphasis on the "oil crash". Concerns and criticisms about the Hydrogen Economy will be addressed by debunking some of the "hydrogen myths". There are three major driving factors for the establishment of the Solar-Hydrogen Economy, i.e. the environment, the economy with the coming "oil crash", and national security. The New Energy decentralization pathway has developed many progressive features, e.g., reducing the dependence on oil, reducing the air pollution and CO II. The technical and economic aspects of the various Solar-Hydrogen energy options and combinations will be analyzed. A proposed 24-hour/day 200 MWe solar-hydrogen power plant for the U.S. with selected energy options will be discussed. There are fast emerging Solar Hydrogen energy infrastructures in the U.S., Europe, Japan and China. Some of the major infrastructure projects in the transportation and energy sectors will be discussed. The current and projected growth in the Solar-Hydrogen Economy through 2045 will be given.

  16. HTTR workshop (workshop on hydrogen production technology)

    International Nuclear Information System (INIS)

    Shiina, Yasuaki; Takizuka, Takakazu

    2004-12-01

    Various research and development efforts have been performed to solve the global energy and environmental problems caused by large consumption of fossil fuels. Research activities on advanced hydrogen production technology by the use of nuclear heat from high temperature gas cooled reactors, for example, have been flourished in universities, research institutes and companies in many countries. The Department of HTTR Project and the Department of Advanced Nuclear Heat Technology of JAERI held the HTTR Workshop (Workshop on Hydrogen Production Technology) on July 5 and 6, 2004 to grasp the present status of R and D about the technology of HTGR and the nuclear hydrogen production in the world and to discuss about necessity of the nuclear hydrogen production and technical problems for the future development of the technology. More than 110 participants attended the Workshop including foreign participants from USA, France, Korea, Germany, Canada and United Kingdom. In the Workshop, the presentations were made on such topics as R and D programs for nuclear energy and hydrogen production technologies by thermo-chemical or other processes. Also, the possibility of the nuclear hydrogen production in the future society was discussed. The workshop showed that the R and D for the hydrogen production by the thermo-chemical process has been performed in many countries. The workshop affirmed that nuclear hydrogen production could be one of the competitive supplier of hydrogen in the future. The second HTTR Workshop will be held in the autumn next year. (author)

  17. Carbon nanotube materials for hydrogen storage

    Energy Technology Data Exchange (ETDEWEB)

    Dillon, A.C.; Parilla, P.A.; Jones, K.M.; Riker, G.; Heben, M.J. [National Renewable Energy Lab., Golden, CO (United States)

    1998-08-01

    Carbon single-wall nanotubes (SWNTs) are essentially elongated pores of molecular dimensions and are capable of adsorbing hydrogen at relatively high temperatures and low pressures. This behavior is unique to these materials and indicates that SWNTs are the ideal building block for constructing safe, efficient, and high energy density adsorbents for hydrogen storage applications. In past work the authors developed methods for preparing and opening SWNTs, discovered the unique adsorption properties of these new materials, confirmed that hydrogen is stabilized by physical rather than chemical interactions, measured the strength of interaction to be {approximately} 5 times higher than for adsorption on planar graphite, and performed infrared absorption spectroscopy to determine the chemical nature of the surface terminations before, during, and after oxidation. This year the authors have made significant advances in synthesis and characterization of SWNT materials so that they can now prepare gram quantities of high-purity SWNT samples and measure and control the diameter distribution of the tubes by varying key parameters during synthesis. They have also developed methods which purify nanotubes and cut nanotubes into shorter segments. These capabilities provide a means for opening the tubes which were unreactive to the oxidation methods that successfully opened tubes, and offer a path towards organizing nanotube segments to enable high volumetric hydrogen storage densities. They also performed temperature programmed desorption spectroscopy on high purity carbon nanotube material obtained from collaborator Prof. Patrick Bernier and finished construction of a high precision Seivert`s apparatus which will allow the hydrogen pressure-temperature-composition phase diagrams to be evaluated for SWNT materials.

  18. Evaluation of hydrogen sulphide test for detection of fecal coliform ...

    African Journals Online (AJOL)

    GREGO

    2007-03-19

    Mar 19, 2007 ... on production of hydrogen sulphide by bacteria that are associated with fecal contamination. This rapid fields test needs no technical staff and the cost is lower than ..... Sources and Potable Water Supplies in Peru.

  19. 2010 Hydrogen and Fuel Cell Global Commercialization & Development Update

    Energy Technology Data Exchange (ETDEWEB)

    none,

    2010-11-01

    This report offers examples of real-world applications and technical progress of hydrogen and fuel cell technologies, including policies adopted by countries to increase technology development and commercialization.

  20. Advanced Hydrogen Turbine Development

    Energy Technology Data Exchange (ETDEWEB)

    Marra, John [Siemens Energy, Inc., Orlando, FL (United States)

    2015-09-30

    Under the sponsorship of the U.S. Department of Energy (DOE) National Energy Technology Laboratories, Siemens has completed the Advanced Hydrogen Turbine Development Program to develop an advanced gas turbine for incorporation into future coal-based Integrated Gasification Combined Cycle (IGCC) plants. All the scheduled DOE Milestones were completed and significant technical progress was made in the development of new technologies and concepts. Advanced computer simulations and modeling, as well as subscale, full scale laboratory, rig and engine testing were utilized to evaluate and select concepts for further development. Program Requirements of: A 3 to 5 percentage point improvement in overall plant combined cycle efficiency when compared to the reference baseline plant; 20 to 30 percent reduction in overall plant capital cost when compared to the reference baseline plant; and NOx emissions of 2 PPM out of the stack. were all met. The program was completed on schedule and within the allotted budget

  1. Adsorption of hydrogen gas and redox processes in clays.

    Science.gov (United States)

    Didier, Mathilde; Leone, Laura; Greneche, Jean-Marc; Giffaut, Eric; Charlet, Laurent

    2012-03-20

    In order to assess the adsorption properties of hydrogen gas and reactivity of adsorbed hydrogen, we measured H(2)(g) adsorption on Na synthetic montmorillonite-type clays and Callovo-Oxfordian (COx) clayrock using gas chromatography. Synthetic montmorillonites with increasing structural Fe(III) substitution (0 wt %, 3.2 wt %, and 6.4 wt % Fe) were used. Fe in the synthetic montmorillonites is principally present as structural Fe(III) ions. We studied the concomitant reduction of structural Fe(III) in the clays using (57)Fe Mössbauer spectrometry. The COx, which mainly contains smectite/illite and calcite minerals, is also studied together with the pure clay fraction of this clayrock. Experiments were performed with dry clay samples which were reacted with hydrogen gas at 90 and 120 °C for 30 to 45 days at a hydrogen partial pressure close to 0.45 bar. Results indicate that up to 0.11 wt % of hydrogen is adsorbed on the clays at 90 °C under 0.45 bar of relative pressure. (57)Fe Mössbauer spectrometry shows that up to 6% of the total structural Fe(III) initially present in these synthetic clays is reduced upon adsorption of hydrogen gas. No reduction is observed with the COx sample in the present experimental conditions.

  2. Technical Note

    African Journals Online (AJOL)

    Administratör

    In this report on four patients, we did not use any of these techniques. The existence and the site of the fistulas was clearly demonstrated using basic but important preoperative detailed assessment and two intraoperative findings. The preoperative referral note that indicated the site of technical difficulty during the previous ...

  3. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball

    2010-01-01

    Operational Experience At the end of the first full-year running period of LHC, CMS is established as a reliable, robust and mature experiment. In particular common systems and infrastructure faults accounted for <0.6 % CMS downtime during LHC pp physics. Technical operation throughout the entire year was rather smooth, the main faults requiring UXC access being sub-detector power systems and rack-cooling turbines. All such problems were corrected during scheduled technical stops, in the shadow of tunnel access needed by the LHC, or in negotiated accesses or access extensions. Nevertheless, the number of necessary accesses to the UXC averaged more than one per week and the technical stops were inevitably packed with work packages, typically 30 being executed within a few days, placing a high load on the coordination and area management teams. It is an appropriate moment for CMS Technical Coordination to thank all those in many CERN departments and in the Collaboration, who were involved in CMS techni...

  4. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball

    2010-01-01

    Operational Experience Since the closure of the detector in February, the technical operation of CMS has been quite smooth and reliable. Some minor interventions in UXC were required to cure failures of power supplies, fans, readout boards and rack cooling connections, but all these failures were repaired in scheduled technical stops or parasitically during access dedicated to fixing LHC technical problems. The only occasion when CMS had to request an access between fills was to search for the source of an alarm from the leak-detection cables mounted in the DT racks. After a few minutes of diagnostic search, a leaking air-purge was found. Replacement was complete within 2 hours. This incident demonstrated once more the value of these leak detection cables; the system will be further extended (during the end of year technical stop) to cover more racks in UXC and the floor beneath the detector. The magnet has also been operating reliably and reacted correctly to the 14s power cut on 29 May (see below). In or...

  5. Technical endoscopy

    International Nuclear Information System (INIS)

    Cavalar, K.O.

    1988-01-01

    A survey is provided on different versions of endoscopes, taking into account the new developments of video endoscopy. With a variety of practical examples it is shown that technical tests using endoscopy are a demanding task for nondestructive testing, whose requirements can only be met on a customized basis. (orig./HP) [de

  6. Technical Training: Technical Training Seminar

    CERN Multimedia

    2004-01-01

    TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch Monday 9 February 2004 From 10:00 to 12:00 - IT Auditorium - bldg. 31, 3rd floor ANSOFT High-Frequency Seminar David Prestaux, Application Engineer, ANSOFT F-78535 BUC, France This Technical Training seminar will present two Ansoft application products: Ansoft HFSS and Ansoft Designer. Ansoft HFSS makes use of the Finite Element Method (FEM) to calculate field solutions from first principles. It can accurately predict all high-frequency behaviours such as dispersion, mode conversion, and losses due to materials and radiation. Ansoft Designer is a suite of design tools to fully integrate high-frequency, physics-based electromagnetic simulations into a seamless system-level simulation environment. Ansoft Designer uses a simple interface to give complete control over every design task, by a method allowing multiple solvers, Solver on Demand. • Introduction • Overview of the Ansoft Total solution • Ansoft HFSS 9...

  7. Hycom Pre - Feasibility study. Final report[Hydrogen communities

    Energy Technology Data Exchange (ETDEWEB)

    Lacobazzi, A; Mario, F di [ENEA, (Italy); Hasenauer, U [Fraunhofer IS, (Germany); Joergensen, B H; Bromand Noergaard, P [Risoe National Lab., (Denmark)

    2005-07-01

    The Quick-start Programme of the European Union Initiative for Growth identifies the hydrogen economy as one of the key areas for investment in the medium term (2004-2015). In this context the HyCOM (Hydrogen Communities) programme has been initiated. The main goal of this programme is the creation of a limited number of strategically sited stand-alone hydrogen communities producing hydrogen from various primary sources (mostly renewables) and using it for heat and electricity production and as fuel for vehicles. This report looks at the establishment of such hydrogen communities, analysing the main technical, economic, social, and environmental aspects as well as financial and regulatory barriers associated with the creation and operation of hydrogen communities. It also proposes a number of concepts for Hydrogen Communities and criteria with which a Hydrogen Community should be evaluated. The study is not in any way intended to be prescriptive. (ln)

  8. Radioactive gas and hydrogen removal after a LOCE at the LOFT Facility

    International Nuclear Information System (INIS)

    McCormick-Barger, J.W.; Sumpter, K.C.

    1979-01-01

    The use of a silver-zeolite halogen adsorber placed in series with a hydrogen catalytic recombiner and a cryogenic noble gas adsorber assembly constitutes a waste gas processing system (WGPS) capable of handling hydrogen and fission product gases following a Loss-of-Coolant Experiment (LOCE). This paper describes: the types and quantities of gases expected to be found at the facility after a failed-fuel LOCE; the purpose of the WGPS; and the general configuration and expected decontamination factors associated with the LOFT WGPS

  9. Dynamics of CO 2 Adsorption on Amine Adsorbents. 2. Insights Into Adsorbent Design

    KAUST Repository

    Bollini, Praveen

    2012-11-21

    Packed bed breakthrough experiments are reported for commercial zeolite 13X and 3-aminopropyl-functionalized SBA-15 silica materials with three different amine loadings. Mass and heat transfer dynamics for all four materials are modeled successfully. Amine adsorbents with open pores are found to exhibit faster mass diffusion rates compared to zeolite 13X. When amine loading is increased by coupling aminopropyl groups, premature breakthrough combined with a long tail is observed. Contrary to conventional physisorbants, finite heat losses to the column wall do not explain the long breakthrough tail. A rate model that accounts for heterogeneity in diffusion was found to accurately capture the breakthrough shape of the high loading material. Batch uptake measurements support the hypothesis that slow diffusion through the polymer phase is what hampers adsorption kinetics in the high amine loading adsorbent. The results emphasize the importance of designing materials that are not overloaded with amine sites, as excessive amine loadings can lead to depressed adsorption kinetics and premature column breakthrough. © 2012 American Chemical Society.

  10. Hydrogen production processes

    International Nuclear Information System (INIS)

    2003-01-01

    The goals of this first Gedepeon workshop on hydrogen production processes are: to stimulate the information exchange about research programs and research advances in the domain of hydrogen production processes, to indicate the domains of interest of these processes and the potentialities linked with the coupling of a nuclear reactor, to establish the actions of common interest for the CEA, the CNRS, and eventually EDF, that can be funded in the framework of the Gedepeon research group. This document gathers the slides of the 17 presentations given at this workshop and dealing with: the H 2 question and the international research programs (Lucchese P.); the CEA's research program (Lucchese P., Anzieu P.); processes based on the iodine/sulfur cycle: efficiency of a facility - flow-sheets, efficiencies, hard points (Borgard J.M.), R and D about the I/S cycle: Bunsen reaction (Colette S.), R and D about the I/S cycle: the HI/I 2 /H 2 O system (Doizi D.), demonstration loop/chemical engineering (Duhamet J.), materials and corrosion (Terlain A.); other processes under study: the Westinghouse cycle (Eysseric C.), other processes under study at the CEA (UT3, plasma,...) (Lemort F.), database about thermochemical cycles (Abanades S.), Zn/ZnO cycle (Broust F.), H 2 production by cracking, high temperature reforming with carbon trapping (Flamant G.), membrane technology (De Lamare J.); high-temperature electrolysis: SOFC used as electrolyzers (Grastien R.); generic aspects linked with hydrogen production: technical-economical evaluation of processes (Werkoff F.), thermodynamic tools (Neveu P.), the reactor-process coupling (Aujollet P.). (J.S.)

  11. Electronic structure of benzene adsorbed on Ni and Cu surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Weinelt, M.; Nilsson, A.; Wassdahl, N. [Uppsala Univ. (Sweden)] [and others

    1997-04-01

    Benzene has for a long time served as a prototype adsorption system of large molecules. It adsorbs with the molecular plane parallel to the surface. The bonding of benzene to a transition metal is typically viewed to involve the {pi} system. Benzene adsorbs weakly on Cu and strongly on Ni. It is interesting to study how the adsorption strength is reflected in the electronic structure of the adsorbate-substrate complex. The authors have used X-ray Emission (XE) and X-ray Absorption (XA) spectroscopies to selectively study the electronic states localized on the adsorbed benzene molecule. Using XES the occupied states can be studies and with XAS the unoccupied states. The authors have used beamline 8.0 and the Swedish endstation equipped with a grazing incidence x-ray spectrometer and a partial yield absorption detector. The resolution in the XES and XAS were 0.5 eV and 0.05 eV, respectively.

  12. Enhanced vanillin production from ferulic acid using adsorbent resin.

    Science.gov (United States)

    Hua, Dongliang; Ma, Cuiqing; Song, Lifu; Lin, Shan; Zhang, Zhaobin; Deng, Zixin; Xu, Ping

    2007-03-01

    High vanillin productivity was achieved in the batch biotransformation of ferulic acid by Streptomyces sp. strain V-1. Due to the toxicity of vanillin and the product inhibition, fed-batch biotransformation with high concentration of ferulic acid was unsuccessful. To solve this problem and improve the vanillin yield, a biotransformation strategy using adsorbent resin was investigated. Several macroporous adsorbent resins were chosen to adsorb vanillin in situ during the bioconversion. Resin DM11 was found to be the best, which adsorbed the most vanillin and the least ferulic acid. When 8% resin DM11 (wet w/v) was added to the biotransformation system, 45 g l(-1) ferulic acid could be added continually and 19.2 g l(-1) vanillin was obtained within 55 h, which was the highest vanillin yield by bioconversion until now. This yield was remarkable for exceeding the crystallization concentration of vanillin and therefore had far-reaching consequence in its downstream processing.

  13. Production of Flocculants, Adsorbents, and Dispersants from Lignin.

    Science.gov (United States)

    Chen, Jiachuan; Eraghi Kazzaz, Armin; AlipoorMazandarani, Niloofar; Hosseinpour Feizi, Zahra; Fatehi, Pedram

    2018-04-10

    Currently, lignin is mainly produced in pulping processes, but it is considered as an under-utilized chemical since it is being mainly used as a fuel source. Lignin contains many hydroxyl groups that can participate in chemical reactions to produce value-added products. Flocculants, adsorbents, and dispersants have a wide range of applications in industry, but they are mainly oil-based chemicals and expensive. This paper reviews the pathways to produce water soluble lignin-based flocculants, adsorbents, and dispersants. It provides information on the recent progress in the possible use of these lignin-based flocculants, adsorbents, and dispersants. It also critically discusses the advantages and disadvantages of various approaches to produce such products. The challenges present in the production of lignin-based flocculants, adsorbents, and dispersants and possible scenarios to overcome these challenges for commercial use of these products in industry are discussed.

  14. Order-disorder transitions in adsorbed systems on magnetic surfaces

    International Nuclear Information System (INIS)

    Aguilera-Granja, F.; Moran-Lopez, J.L.; Instituto Politecnico Nacional, Mexico City. Centro de Investigacion y de Estudios Avanzados); Falicov, L.M.

    1984-01-01

    It is investigated the effect of adsorbed atoms on the magnetic properties of ferromagnets. The Ising model is employed considering nearest neigbours with antiferromagnetic coupling between atoms. (M.W.O.) [pt

  15. Production of Flocculants, Adsorbents, and Dispersants from Lignin

    Directory of Open Access Journals (Sweden)

    Jiachuan Chen

    2018-04-01

    Full Text Available Currently, lignin is mainly produced in pulping processes, but it is considered as an under-utilized chemical since it is being mainly used as a fuel source. Lignin contains many hydroxyl groups that can participate in chemical reactions to produce value-added products. Flocculants, adsorbents, and dispersants have a wide range of applications in industry, but they are mainly oil-based chemicals and expensive. This paper reviews the pathways to produce water soluble lignin-based flocculants, adsorbents, and dispersants. It provides information on the recent progress in the possible use of these lignin-based flocculants, adsorbents, and dispersants. It also critically discusses the advantages and disadvantages of various approaches to produce such products. The challenges present in the production of lignin-based flocculants, adsorbents, and dispersants and possible scenarios to overcome these challenges for commercial use of these products in industry are discussed.

  16. Comparative analysis of the efficiencies of two low cost adsorbents ...

    African Journals Online (AJOL)

    ISHIOMA

    tanning, metallurgical operation and manufacturing have led to the release ... pulmonary fibrosis and inhibit many enzymatic functions. (Liphadzi ... sector is a low cost adsorbent for heavy metal but has ... as its economic value is less. The aim ...

  17. Selectivity of β-Sitosterol Imprinted Polymers as Adsorbent

    Science.gov (United States)

    Fauziah, St.; Hariani Soekamto, Nunuk; Taba, Paulina; Bachri Amran, Muh

    2018-03-01

    Molecularly Imprinted Polymers (MIPs) are smart materials that have been used as adsorbents in separation processes of compounds because they have a memorial effect to a certain compound. In this research, MIP synthesized was used as adsorbent for β-sitosterol. The objective of the research was to know the selectivity of MIP in adsorbing β-sitosterol. The concentrations of β-sitosterol after adsorption and desorption were analyzed by a UV-Vis spectrophotometer and the selectivity test was analyzed by HPLC. Result showed that the MIP had high adsorption ability ( qe ). The recovery of β-sitosterol from MIP for the adsorption-desorption process was 68.48%. The MIP was very selective to β-sitosterol compared to cholesterol because it can adsorb β-sitosterol as many as 100%, whereas the adsorption of cholesterol was only 30.27 %.

  18. Characterization of novel adsorbents for radiostrontium reduction in foods

    International Nuclear Information System (INIS)

    Puziy, A.M.; Bengtsson, G.B.; Hansen, H.S.

    1999-01-01

    Distribution coefficients, pH dependence, isotherms, kinetics and breakthrough curves of Sr binding have been measured on several types of adsorbents (carbons modified with titanium silicate, crystalline titanium silicate, mixed titanium-manganese oxide, and synthetic zeolites A4 and P) from different water solutions. It is concluded that acid-base properties of the adsorbent is very important for Sr binding. Titanium silicate based adsorbents had reduced chemical stability in an artificial food fluid below pH 2, the mixed titanium manganese oxide below pH 6, zeolite A4 below pH 5 and zeolite P below pH 7. Consideration is given to the feasibility of the adsorbents for food decontamination. (author)

  19. Adsorption of β-galactosidase on silica and aluminosilicate adsorbents

    Science.gov (United States)

    Atyaksheva, L. F.; Dobryakova, I. V.; Pilipenko, O. S.

    2015-03-01

    It is shown that adsorption of β-galactosidase of Aspergillus oryzae fungi on mesoporous and biporous silica and aluminosilicate adsorbents and the rate of the process grow along with the diameter of the pores of the adsorbent. It is found that the shape of the adsorption isotherms changes as well, depending on the texture of the adsorbent: the Michaelis constant rises from 0.3 mM for the enzyme in solution to 0.4-0.5 mM for the enzyme on a surface in the hydrolysis of o-nitrophenyl-β-D-galactopyranoside. It is concluded that β-galactosidase displays its maximum activity on the surface of biporous adsorbents.

  20. Adsorption of uranium on adsorbents produced from used tires

    International Nuclear Information System (INIS)

    Mahramanlioglu, M.

    2003-01-01

    Potential use of adsorbents produced from used tires for the removal of uranium from aqueous solutions is investigated. Two different adsorbents were used including char and activated carbon produced from used tires. The surface area was larger on activated carbon. Adsorption experiments were carried out as a function of time, adsorbent concentration, pH and initial concentration of uranium. The adsorption kinetics was found to follow the Lagergren equation. The rate constants of intraparticle diffusion and mass transfer coefficients were calculated. It was shown that the equilibrium data could be fitted by the Langmuir and Freundlich equations. The adsorption of uranium in the presence of different cations were also studied and the results were correlated with the ionic potential of the cations. It was demonstrated that the activated carbon produced from used tires can be considered as an adsorbent that has a commercial potential for uranium removal. (author)

  1. In situ STM imaging of the structures of pentacene molecules adsorbed on Au(111).

    Science.gov (United States)

    Pong, Ifan; Yau, Shuehlin; Huang, Peng-Yi; Chen, Ming-Chou; Hu, Tarng-Shiang; Yang, Yawchia; Lee, Yuh-Lang

    2009-09-01

    In situ scanning tunneling microscope (STM) was used to examine the spatial structures of pentacene molecules adsorbed onto a Au(111) single-crystal electrode from a benzene dosing solution containing 16-400 microM pentacene. Molecular-resolution STM imaging conducted in 0.1 M HClO(4) revealed highly ordered pentacene structures of ( radical31 x radical31)R8.9 degrees , (3 x 10), ( radical31 x 10), and ( radical7 x 2 radical7)R19.1 degrees adsorbed on the reconstructed Au(111) electrode dosed with different pentacene solutions. These pentacene structures and the reconstructed Au(111) substrate were stable between 0.2 and 0.8 V [vs reversible hydrogen electrode, RHE]. Increasing the potential to E > 0.8 V lifted the reconstructed Au(111) surface and disrupted the ordered pentacene adlattices simultaneously. Ordered pentacene structures could be restored by applying potentials negative enough to reinforce the reconstructed Au(111). At potentials negative of 0.2 V, the adsorption of protons became increasingly important to displace adsorbed pentacene admolecules. Although the reconstructed Au(111) structure was not essential to produce ordered pentacene adlayers, it seemed to help the adsorption of pentacene molecules in a long-range ordered pattern. At room temperature (25 degrees C), approximately 100 pentacene molecules seen in STM images could rotate and align themselves to a neighboring domain in 10 s, suggesting that pentacene admolecules could be mobile on Au(111) under the STM imaging conditions of -150 mV in bias voltage and 1 nA in feedback current.

  2. Role of adsorbates on current fluctuations in DC field emission

    International Nuclear Information System (INIS)

    Luong, M.; Bonin, B.; Long, H.; Safa, H.

    1996-01-01

    Field emission experiments in DC regime usually show important current fluctuations for a fixed electric field. These fluctuations are attributed to adsorbed layers (molecules or atoms), liable to affect the work function, height and shape of the potential barrier binding the electron in the metal. The role of these adsorbed species is investigated by showing that the field emission from a well desorbed sample is stable and reproducible and by comparing the emission from the same sample before and after desorption. (author)

  3. Simulations of the Static Friction Due to Adsorbed Molecules

    OpenAIRE

    He, Gang; Robbins, Mark O.

    2001-01-01

    The static friction between crystalline surfaces separated by a molecularly thin layer of adsorbed molecules is calculated using molecular dynamics simulations. These molecules naturally lead to a finite static friction that is consistent with macroscopic friction laws. Crystalline alignment, sliding direction, and the number of adsorbed molecules are not controlled in most experiments and are shown to have little effect on the friction. Temperature, molecular geometry and interaction potenti...

  4. Vanadium (4) complexing in phase of adsorbent with benzimidazole groups

    Energy Technology Data Exchange (ETDEWEB)

    Shvoeva, O P; Kuchava, G P; Evtikova, G A; Belyaeva, V K; Myasoedova, G V; Marov, I N [AN SSSR, Moscow (USSR). Inst. Geokhimii i Analiticheskoj Khimii

    1989-04-01

    Equilibrium and kinetic characteristics of V{sup 4+} sorption by POLYORGS XI-H adsorbent with benzimidazole groups (BIm) are investigated. Using ESR method it is stated that (VO{sup 2+}):(BIm)1:2 complex, where VO{sup 2+} is combined with nitrogen atoms of two imidazole groups, is formed in adsorbent phase. The highest distribution factor of 4.7x10{sup 3} is attained at pH6.

  5. Vanadium (4) complexing in phase of adsorbent with benzimidazole groups

    International Nuclear Information System (INIS)

    Shvoeva, O.P.; Kuchava, G.P.; Evtikova, G.A.; Belyaeva, V.K.; Myasoedova, G.V.; Marov, I.N.

    1989-01-01

    Equilibrium and kinetic characteristics of V 4+ sorption by POLYORGS XI-H adsorbent with benzimidazole groups (BIm) are investigated. Using ESR method it is stated that [VO 2+ ]:[BIm]1:2 complex, where VO 2+ is combined with nitrogen atoms of two imidazole groups, is formed in adsorbent phase. The highest distribution factor of 4.7x10 3 is attained at pH6

  6. Efforts to Consolidate Chalcogels with Adsorbed Iodine

    Energy Technology Data Exchange (ETDEWEB)

    Riley, Brian J.; Pierce, David A.; Chun, Jaehun

    2013-08-28

    This document discusses ongoing work with non-oxide aerogels, called chalcogels, that are under development at the Pacific Northwest National Laboratory as sorbents for gaseous iodine. Work was conducted in fiscal year 2012 to demonstrate the feasibility of converting Sn2S3 chalcogel without iodine into a glass. This current document summarizes the work conducted in fiscal year 2013 to assess the consolidation potential of non-oxide aerogels with adsorbed iodine. The Sn2S3 and Sb13.5Sn5S20 chalcogels were selected for study. The first step in the process for these experiments was to load them with iodine (I2). The I2 uptake was ~68 mass% for Sn2S3 and ~50 mass% for Sb13.5Sn5S20 chalcogels. X-ray diffraction (XRD) of both sets of sorbents showed that metal-iodide complexes were formed during adsorption, i.e., SnI4 for Sn2S3 and SbI3 for Sb13.5Sn5S20. Additionally, metal-sulfide-iodide complexes were formed, i.e., SnSI for Sn2S3 and SbSI for Sb13.5Sn5S20. No XRD evidence for unreacted iodine was found in any of these samples. Once the chalcogels had reached maximum adsorption, the consolidation potential was assessed. Here, the sorbents were heated for consolidation in vacuum-sealed quartz vessels. The Sb13.5Sn5S20 chalcogel was heated both (1) in a glassy carbon crucible within a fused quartz tube and (2) in a single-containment fused quartz tube. The Sn2S3 chalcogel was only heated in a single-containment fused quartz tube. In both cases with the single-containment fused quartz experiments, the material consolidated nicely. However, in both cases, there were small fractions of metal iodides not incorporated into the final product as well as fused quartz particles within the melt due to the sample attacking the quartz wall during the heat treatment. The Sb13.5Sn5S20 did not appear to attack the glassy carbon crucible so, for future experiments, it would be ideal to apply a coating, such as pyrolytic graphite, to the inner walls of the fused quartz vessel to prevent

  7. Hydrogen trapping ability of the pyridine-lithium⁺ (1:1) complex.

    Science.gov (United States)

    Chattaraj, Saparya; Srinivasu, K; Mondal, Sukanta; Ghosh, Swapan K

    2015-03-26

    Theoretical studies have been carried out at different levels of theory to verify the hydrogen adsorption characteristics of pyridine-lithium ion (1:1) complexes. The nature of interactions associated with the bonding between pyridine and lithium as well as that between lithium and adsorbed molecular hydrogen is studied through the calculation of electron density and electron-density-based reactivity descriptors. The pyridine-lithium ion complex has been hydrogenated systematically around the lithium site, and each lithium site is found to adsorb a maximum of four hydrogen molecules with an interaction energy of ∼-4.0 kcal/mol per molecule of H2. The fate of the hydrogen adsorbed in a pyridine-lithium ion complex (corresponding to the maximum adsorption) is studied in the course of a 2 ps time evolution through ab initio molecular dynamics simulation at different temperatures. The results reveal that the complex can hold a maximum of four hydrogen molecules at a temperature of 77 K, whereas it can hold only two molecules of hydrogen at 298 K.

  8. Solar Hydrogen Fuel Cell Projects at Brooklyn Tech

    Science.gov (United States)

    Fedotov, Alex; Farah, Shadia; Farley, Daithi; Ghani, Naureen; Kuo, Emmy; Aponte, Cecielo; Abrescia, Leo; Kwan, Laiyee; Khan, Ussamah; Khizner, Felix; Yam, Anthony; Sakeeb, Khan; Grey, Daniel; Anika, Zarin; Issa, Fouad; Boussayoud, Chayama; Abdeldayem, Mahmoud; Zhang, Alvin; Chen, Kelin; Chan, Kameron Chuen; Roytman, Viktor; Yee, Michael

    2010-01-01

    This article describes the projects on solar hydrogen powered vehicles using water as fuel conducted by teams at Brooklyn Technical High School. Their investigations into the pure and applied chemical thermodynamics of hydrogen fuel cells and bio-inspired devices have been consolidated in a new and emerging sub-discipline that they define as solar…

  9. Maximizing Light Utilization Efficiency and Hydrogen Production in Microalgal Cultures

    Energy Technology Data Exchange (ETDEWEB)

    Melis, Anastasios [Univ. of California, Berkeley, CA (United States)

    2014-12-31

    The project addressed the following technical barrier from the Biological Hydrogen Production section of the Fuel Cell Technologies Program Multi-Year Research, Development and Demonstration Plan: Low Sunlight Utilization Efficiency in Photobiological Hydrogen Production is due to a Large Photosystem Chlorophyll Antenna Size in Photosynthetic Microorganisms (Barrier AN: Light Utilization Efficiency).

  10. Irradiation Degradation of Adsorbents for Minor Actinides Recovery

    International Nuclear Information System (INIS)

    Watanabe, S.; Sano, Y.; Kofuji, H.; Takeuchi, M.; Koizumi, T.

    2015-01-01

    Extraction chromatography is one of the promising technologies for minor actinides (MA: Am and Cm) recovery from high-level liquid waste. The degradation behaviour of the organic species in the adsorbents under radiation exposure is important to discuss the safety and durability of the adsorbent in the extraction chromatography process. In this study, gamma-ray irradiation experiments on TODGA/SiO 2 -P adsorbent were carried out to investigate the degradation products from radiolysis of the adsorbent. The degraded organic species eluted from the adsorbent and those remaining inside the adsorbent were thoroughly identified by GC/MS, FT-IR and NMR analyses. The species suspected as hydrolysis products of TODGA were mainly detected from the analyses. Since some radicals such as.H or.OH are generated by the gamma-ray irradiation on water molecules, it was discussed that the radicals products from radiolysis of HNO 3 solution are related to the degradation reaction of the extractants. (authors)

  11. Present status of research on hydrogen energy and perspective of HTGR hydrogen production system

    Energy Technology Data Exchange (ETDEWEB)

    Miyamoto, Yoshiaki; Ogawa, Masuro; Akino, Norio [Japan Atomic Energy Research Inst., Oarai, Ibaraki (Japan). Oarai Research Establishment] [and others

    2001-03-01

    A study was performed to make a clear positioning of research and development on hydrogen production systems with a High Temperature Gas-cooled Reactor (HTGR) under currently promoting at the Japan Atomic Energy Research Institute through a grasp of the present status of hydrogen energy, focussing on its production and utilization as an energy in future. The study made clear that introduction of safe distance concept for hydrogen fire and explosion was practicable for a HTGR hydrogen production system, including hydrogen properties and need to provide regulations applying to handle hydrogen. And also generalization of hydrogen production processes showed technical issues of the HTGR system. Hydrogen with HTGR was competitive to one with fossil fired system due to evaluation of production cost. Hydrogen is expected to be used as promising fuel of fuel cell cars in future. In addition, the study indicated that there were a large amount of energy demand alternative to high efficiency power generation and fossil fuel with nuclear energy through the structure of energy demand and supply in Japan. Assuming that hydrogen with HTGR meets all demand of fuel cell cars, an estimation would show introduction of the maximum number of about 30 HTGRs with capacity of 100 MWt from 2020 to 2030. (author)

  12. Composition of Surface Adsorbed Layer of TiO2 Stored in Ambient Air

    Directory of Open Access Journals (Sweden)

    Zakharenko V.S.

    2017-11-01

    Full Text Available The processes of dark, UV, and visible light promoted desorption of surface species were investigated for three different TiO2 samples: TiO2 prepared by dispersion of the titania single crystal, TiO2 prepared by combustion of a pyrotechnic mixture in air, and commercial TiO2 P25. The composition of the adsorbed layer was identified in the dark and under UV and visible light irradiation. The composition of desorption products showed the dependence of the adsorption layer state on the TiO2 nature. Methane photodesorption was detected only for the commercial TiO2 P25. Possible reasons for methane emission include the capturing of complete molecules during the TiO2 production process and photocatalytic hydrogenation of CO2 under UV-light.

  13. Inelastic neutron scattering of H{sub 2} adsorbed in HKUST-1

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Y. [Department of Materials and Engineering, University of Maryland, College Park, MD 20742 (United States); NIST Center for Neutron Research, 100 Bureau Drive, Gaithersburg, MD 20899-8562 (United States); Brown, C.M. [NIST Center for Neutron Research, 100 Bureau Drive, Gaithersburg, MD 20899-8562 (United States); Indiana University Cyclotron Facility, Indiana University, 2401 Milo B. Sampson Lane, Bloomington, IN 47408 (United States)], E-mail: craig.brown@nist.gov; Neumann, D.A. [NIST Center for Neutron Research, 100 Bureau Drive, Gaithersburg, MD 20899-8562 (United States); Peterson, V.K.; Kepert, C.J. [School of Chemistry, University of Sydney, NSW 2006 (Australia)

    2007-10-31

    A series of inelastic neutron scattering (INS) investigations of hydrogen adsorbed in activated HKUST-1 (Cu{sub 3}(1,3,5-benzenetricarboxylate){sub 2}) result in INS spectra with rich features, even at very low loading (<1.0 H{sub 2}:Cu). The distinct inelastic features in the spectra show that there are three binding sites that are progressively populated when the H{sub 2} loading is less than 2.0 H{sub 2}:Cu, which is consistent with the result obtained from previous neutron powder diffraction experiments. The temperature dependence of the INS spectra reveals the relative binding enthalpies for H{sub 2} at each site.

  14. Gold recovery from low concentrations using nanoporous silica adsorbent

    Science.gov (United States)

    Aledresse, Adil

    The development of high capacity adsorbents with uniform porosity denoted 5%MP-HMS (5% Mercaptopropyl-Hexagonal Mesoporous Structure) to extract gold from noncyanide solutions is presented. The preliminary studies from laboratory simulated noncyanide gold solutions show that the adsorption capacities of these materials are among the highest reported. The high adsorption saturation level of these materials, up to 1.9 mmol/g (37% of the adsorbent weight) from gold chloride solutions (potassium tetrachloroaurate) and 2.9 mmol/g (57% of the adsorbent weight) from gold bromide solutions (potassium tetrabromoaurate) at pH = 2, is a noteworthy feature of these materials. This gold loading from [AuC4]- and [AuBr4 ]- solutions corresponds to a relative Au:S molar ratio of 2.5:1 and 3.8:1, respectively. These rates are significantly higher than the usual 1:1 (Au:S) ratio expected for metal ion binding with the material. The additional gold ions loaded have been spontaneously reduced to metallic gold in the mesoporous material. Experimental studies indicated high maximum adsorptions of gold as high as 99.9% recovery. Another promising attribute of these materials is their favourable adsorption kinetics. The MP-HMS reaches equilibrium (saturation) in less than 1 minute of exposure in gold bromide and less than 10 minutes in gold chloride. The MP-HMS materials adsorption is significantly improved by agitation and the adsorption capacity of Au (III) ions increases with the decrease in pH. The recovery of adsorbed gold and the regeneration of spent adsorbent were investigated for MP-HMS adsorbent. The regenerated adsorbent (MP-HMS) maintained its adsorption capacity even after repeated use and all the gold was successfully recovered from the spent adsorbent. For the fist time, a promising adsorbent system has been found that is capable of effectively concentrating gold thiosulphate complexes, whereas conventional carbon-inpulp (CIP) and carbon-in-leach (CIL) systems fail. The

  15. Cell for studying electron-adsorbed gas interactions; Cellule d'etudes des interactions electron-gaz adsorbe

    Energy Technology Data Exchange (ETDEWEB)

    Golowacz, H; Degras, D A [Commissariat a l' Energie Atomique, 91 - Saclay (France). Centre d' Etudes Nucleaires, Deptartement de Physique des Plasmas et de la Fusion Controlee, Service de Physique Appliquee, Service de Physique des Interractions Electroniques, Section d' Etude des Interactions Gaz-Solides

    1967-07-01

    The geometry and the technology of a cell used for investigations on electron-adsorbed gas interactions are described. The resonance frequencies of the surface ions which are created by the electron impact on the adsorbed gas are predicted by simplified calculations. The experimental data relative to carbon monoxide and neon are in good agreement with these predictions. (authors) [French] Les caracteristiques geometriques et technologiques generales d'une cellule d'etude des interactions entre un faisceau d'electrons et un gaz adsorbe sont donnees. Un calcul simplifie permet de prevoir les frequences de resonance des ions de surface crees par l'impact des electrons sur le gaz adsorbe. Les donnees experimentales sur l'oxyde de carbone et le neon confirment les previsions du calcul. (auteurs)

  16. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball

    Overview From a technical perspective, CMS has been in “beam operation” state since 6th November. The detector is fully closed with all components operational and the magnetic field is normally at the nominal 3.8T. The UXC cavern is normally closed with the radiation veto set. Access to UXC is now only possible during downtimes of LHC. Such accesses must be carefully planned, documented and carried out in agreement with CMS Technical Coordination, Experimental Area Management, LHC programme coordination and the CCC. Material flow in and out of UXC is now strictly controlled. Access to USC remains possible at any time, although, for safety reasons, it is necessary to register with the shift crew in the control room before going down.It is obligatory for all material leaving UXC to pass through the underground buffer zone for RP scanning, database entry and appropriate labeling for traceability. Technical coordination (notably Stephane Bally and Christoph Schaefer), the shift crew and run ...

  17. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball and W. Zeuner

    2011-01-01

    In this report we will review the main achievements of the Technical Stop and the progress of several centrally-managed projects to support CMS operation and maintenance and prepare the way for upgrades. Overview of the extended Technical Stop  The principal objectives of the extended Technical Stop affecting the detector itself were the installation of the TOTEM T1 telescopes on both ends, the readjustment of the alignment link-disk in YE-2, the replacement of the light-guide sleeves for all PMs of both HFs, and some repairs on TOTEM T2 and CASTOR. The most significant tasks were, however, concentrated on the supporting infrastructure. A detailed line-by-line leak search was performed in the C6F14 cooling system of the Tracker, followed by the installation of variable-frequency drives on the pump motors of the SS1 and SS2 tracker cooling plants to reduce pressure transients during start-up. In the electrical system, larger harmonic filters were installed in ...

  18. Destructive hydrogenation

    Energy Technology Data Exchange (ETDEWEB)

    Terrisse, H; Dufour, L

    1929-01-21

    Oils of high boiling point, e.g. gas oil, lamp oil, schist oil, brown coal tar etc., are converted into motor benzine by heating them at 200 to 500/sup 0/C under pressure of 5 to 40 kilograms/cm/sup 2/ in the presence of ferrous chloride and gases such as hydrogen, or water gas, the desulfurization of the oils proceeding simultaneously. One kilogram of lamp oil and 100 g. ferrous chloride are heated in an autoclave in the presence of water gas under a pressure of 18 kg/cm/sup 2/ to 380 to 400/sup 0/C. The gaseous products are allowed to escape intermittently and are replaced by fresh water gas. A product distilling between 35 and 270/sup 0/C is obtained.

  19. Sc-Decorated WS_2 Nanoribbons as Hydrogen Storage Media

    International Nuclear Information System (INIS)

    Xu Bin; Wang Yu-Sheng; Zhang Jing; Song Na-Hong; Li Meng; Yi Lin

    2016-01-01

    The hydrogen storage behavior of Sc-decorated WS_2 monolayer and WS_2 nanoribbons is systematically studied by using first principles calculations based on the density functional theory. The present results indicate that an Sc-decorated WS_2 monolayer is not suitable for storing hydrogen due to the weak interaction between the monolayer WS_2 sheet and the Sc atoms. It is found that both the hybridization mechanism and the Coulomb attraction make the Sc atoms stably adsorb on the edges of WS_2 nanoribbons without clustering. The 2Sc/WS_2 NRs system can adsorb at most eight H_2 molecules with average adsorption energy of 0.20 eV/H_2. The results show that the desorption of H_2 is possible by lowering the pressure or by increasing the temperature. (paper)

  20. Materials for Hydrogen Storage in Nanocavities: Design criteria

    Energy Technology Data Exchange (ETDEWEB)

    Reguera, E. [Centro de Investigacion en Ciencia Aplicada y Tecnologia Avanzada del IPN, Unidad Legaria, Legaria 694, Col. Irrigacion (Mexico)

    2009-11-15

    The adsorption potential for a given adsorbate depends of both, material surface and adsorbate properties. In this contribution the possible guest-host interactions for H{sub 2} within a cavity or on a surface are discussed considering the molecule physical properties. Five different interactions contribute to the adsorption forces for this molecule: 1) quadrupole moment interaction with the local electric field gradient; 1) electron cloud polarization by a charge center; 3) dispersive forces (van der Waals); 4) quadrupole moment versus quadrupole moment between neighboring H{sub 2} molecules, and, 5) H{sub 2} coordination to a metal center. The relative importance of these five interactions for the hydrogen storage in nanocavities is discussed from experimental evidences in order to extract materials design criteria for molecular hydrogen storage. (author)

  1. Adsorption methods for hydrogen isotope storage on zeolitic sieves

    International Nuclear Information System (INIS)

    Cristescu, Ioana; Cristescu, Ion; Vasut, F.; Brad, S.; Lazar, A.

    2001-01-01

    For hydrogen isotope separation, adsorption molecular sieves and active carbon were used. Adsorption process proceeds at liquid nitrogen and liquid hydrogen temperatures. Commercial zeolites have the same proprieties with natural zeolites, but they have a regular pore structure. They also have affinity for molecules of different size with defined shapes. Experimental results obtained at liquid nitrogen temperature (77.4 K) and liquid hydrogen revealed the efficient behaviour of the active carbon and zeolitic sieves for hydrogen isotopes temporary storage. We study adsorption of the synthetic zeolites in a wide range of temperatures and pressures and we used the molecular sieves 4A, 5A and active carbon. The 4A and 5A zeolites have a tridimensional structure with 11.4 A diameter. When the hydration water is eliminated, the material keeps a porous structure. The porous volume represents 45% from the zeolite mass for 4A and 5A sieves. The activation temperature of the zeolite and the carbon is very important for obtaining a high adsorption capacity. If the temperature used for activation is low, the structural water will be not eliminated and the adsorption capacity will be low. The excessive temperature will destroy the porous structure. The adsorption capacity for the hydrogen isotopes was calculated with the relation: A = V ads /m (cm 3 /g). The adsorption capacity and efficiency for the adsorbent materials, are given. Physical adsorption process of the hydrogen isotopes was carried out at liquid nitrogen temperature. The flux gas used in the adsorption system is composed of dry deuterium and protium. This mixture is cooled in liquid nitrogen and then is passed to the adsorbent getter at the same temperature (77.4 K). The gas flux in the adsorbent getter is 5 and 72 l/h (which correspond to 0.008 and 0.134 discharge velocity, respectively). (authors)

  2. Study on the adsorption performance of composite adsorbent of CaCl2 and expanded graphite with ammonia as adsorbate

    International Nuclear Information System (INIS)

    Li, S.L.; Wu, J.Y.; Xia, Z.Z.; Wang, R.Z.

    2009-01-01

    A novel constant volume test unit was built to study the adsorption performance of a new type composite adsorbent. This test unit can measure the adsorption isosteres of the working pairs. The adsorption isosteres are the curves of the adsorption pressure variation with the adsorption temperatures at constant adsorption quantities. Compared to the former test results of isothermals and isobars, the isosteres are better for the calculation of the adsorption heat, desorption heat and the selection the adsorption working pairs. Three experimental results were obtained: the first result was that the expanded graphite powders were superior to the expandable graphite powders to facilitate the transportation of working fluid in the composite adsorbent. The second one was that the composite adsorbent treated by solution is more homogeneous than the simple mixed composite adsorbent and the treated composite adsorbent has a better mass transfer performance. The last one was that the adsorption isosteres was the same one not only in the heating process but also in the cooling process and this performance was not relevant to the homogeneity of the composite adsorbent

  3. Theoretical investigation on the alkali-metal doped BN fullerene as a material for hydrogen storage

    International Nuclear Information System (INIS)

    Venkataramanan, Natarajan Sathiyamoorthy; Belosludov, Rodion Vladimirovich; Note, Ryunosuke; Sahara, Ryoji; Mizuseki, Hiroshi; Kawazoe, Yoshiyuki

    2010-01-01

    Graphical abstract: First-principles calculations have been used to investigate hydrogen adsorption on alkali atom doped B 36 N 36 clusters. Adsorption of alkali atoms involves a charge transfer process, creating positively-charged alkali atoms and this polarizes the H 2 molecules and increases their binding energy. The maximum hydrogen storage capacity of Li doped BN fullerene is 8.9 wt.% in which 60 hydrogen atoms were chemisorbed and 12 H 2 were adsorbed in molecular form. - Abstract: First-principles calculations have been used to investigate hydrogen adsorption on alkali atom doped B 36 N 36 clusters. The alkali atom adsorption takes place near the six tetragonal bridge sites available on the cage, thereby avoiding the notorious clustering problem. Adsorption of alkali atoms involves a charge transfer process, creating positively charged alkali atoms and this polarizes the H 2 molecules thereby, increasing their binding energy. Li atom has been found to adsorb up to three hydrogen molecules with an average binding energy of 0.189 eV. The fully doped Li 6 B 36 N 36 cluster has been found to hold up to 18 hydrogen molecules with the average binding energy of 0.146 eV. This corresponds to a gravimetric density of hydrogen storage of 3.7 wt.%. Chemisorption on the Li 6 B 36 N 36 has been found to be an exothermic reaction, in which 60 hydrogen atoms chemisorbed with an average chemisorption energy of -2.13 eV. Thus, the maximum hydrogen storage capacity of Li doped BN fullerene is 8.9 wt.% in which 60 hydrogen atoms were chemisorbed and 12 hydrogen molecules were adsorbed in molecular form.

  4. Development of Advanced Small Hydrogen Engines

    Energy Technology Data Exchange (ETDEWEB)

    Sapru, Krishna; Tan, Zhaosheng; Chao, Ben

    2010-09-30

    The main objective of the project is to develop advanced, low cost conversions of small (< 25 hp) gasoline internal combustion engines (ICEs) to run on hydrogen fuel while maintaining the same performance and durability. This final technical report summarizes the results of i) the details of the conversion of several small gasoline ICEs to run on hydrogen, ii) the durability test of a converted hydrogen engine and iii) the demonstration of a prototype bundled canister solid hydrogen storage system. Peak power of the hydrogen engine achieves 60% of the power output of the gasoline counterpart. The efforts to boost the engine power with various options including installing the over-sized turbocharger, retrofit of custom-made pistons with high compression ratio, an advanced ignition system, and various types of fuel injection systems are not realized. A converted Honda GC160 engine with ACS system to run with hydrogen fuel is successful. Total accumulative runtime is 785 hours. A prototype bundled canister solid hydrogen storage system having nominal capacity of 1.2 kg is designed, constructed and demonstrated. It is capable of supporting a wide range of output load of a hydrogen generator.

  5. Configuration and technology implications of potential nuclear hydrogen system applications.

    Energy Technology Data Exchange (ETDEWEB)

    Conzelmann, G.; Petri, M.; Forsberg, C.; Yildiz, B.; ORNL

    2005-11-05

    Nuclear technologies have important distinctions and potential advantages for large-scale generation of hydrogen for U.S. energy services. Nuclear hydrogen requires no imported fossil fuels, results in lower greenhouse-gas emissions and other pollutants, lends itself to large-scale production, and is sustainable. The technical uncertainties in nuclear hydrogen processes and the reactor technologies needed to enable these processes, as well waste, proliferation, and economic issues must be successfully addressed before nuclear energy can be a major contributor to the nation's energy future. In order to address technical issues in the time frame needed to provide optimized hydrogen production choices, the Nuclear Hydrogen Initiative (NHI) must examine a wide range of new technologies, make the best use of research funding, and make early decisions on which technology options to pursue. For these reasons, it is important that system integration studies be performed to help guide the decisions made in the NHI. In framing the scope of system integration analyses, there is a hierarchy of questions that should be addressed: What hydrogen markets will exist and what are their characteristics? Which markets are most consistent with nuclear hydrogen? What nuclear power and production process configurations are optimal? What requirements are placed on the nuclear hydrogen system? The intent of the NHI system studies is to gain a better understanding of nuclear power's potential role in a hydrogen economy and what hydrogen production technologies show the most promise. This work couples with system studies sponsored by DOE-EE and other agencies that provide a basis for evaluating and selecting future hydrogen production technologies. This assessment includes identifying commercial hydrogen applications and their requirements, comparing the characteristics of nuclear hydrogen systems to those market requirements, evaluating nuclear hydrogen configuration options

  6. Technical Training: Technical Training Seminar

    CERN Multimedia

    2004-01-01

    Tuesday 30 March TECHNICAL TRAINING SEMINAR From 9:00 to 12:00 and from 13:00 to 16:00 hrs - Council Chamber, Salle B, Salle des Pas Perdus National Instruments (NI) on Tour 2004 Claudia Jüngel, Evrem Yarkin, Joel Clerc, Hervé Baour / NATIONAL INSTRUMENTS The special event NI on Tour 2004, run in Germany, Austria and Switzerland, will be at CERN on March 30. Technical seminars and free introductory courses will be offered all day long in the Council Chamber, Salle B, and Salle des Pas Perdus (buildings 61 and 503). Technical conferences: 09:00 - 12:00 Data acquisition systems on PCs. Industrial measurement and control techniques. 13:00 - 16:00 Advanced LabVIEW software and PXI instrumentation. Measuring instruments and system components for teststand automation. Introductory courses: 09:00 - 12:00 DIAdem: Data analysis and presentation 13:00 - 16:00 Data acquisition with LabVIEW Language: English and French Free special seminar. Registration is recommended with National Instruments Switzerland (please sp...

  7. Technical Training: Technical Training Seminar

    CERN Multimedia

    2004-01-01

    Tuesday 30 March TECHNICAL TRAINING SEMINAR From 9:00 to 12:00 and from 13:00 to 16:00 hrs - Council Chamber, Salle B, Salle des Pas Perdus National Instruments (NI) on Tour 2004 Claudia Jüngel, Evrem Yarkin, Joel Clerc, Hervé Baour / NATIONAL INSTRUMENTS The special event NI on Tour 2004, run in Germany, Austria and Switzerland, will be at CERN on March 30. Technical seminars and free introductory courses will be offered all day long in the Council Chamber, Salle B, and Salle des Pas Perdus (buildings 61 and 503). Technical conferences: 09:00 - 12:00 Data acquisition systems on PCs. Industrial measurement and control techniques. 13:00 - 16:00 Advanced LabVIEW software and PXI instrumentation. Measuring instruments and system components for teststand automation. Introductory courses: 09:00 - 12:00 DIAdem: Data analysis and presentation 13:00 - 16:00 Data acquisition with LabVIEW Language: English and French Free special seminar. Registration is recommended with National Instruments Swi...

  8. Hydrogen Plasma Processing of Iron Ore

    Science.gov (United States)

    Sabat, Kali Charan; Murphy, Anthony B.

    2017-06-01

    Iron is currently produced by carbothermic reduction of oxide ores. This is a multiple-stage process that requires large-scale equipment and high capital investment, and produces large amounts of CO2. An alternative to carbothermic reduction is reduction using a hydrogen plasma, which comprises vibrationally excited molecular, atomic, and ionic states of hydrogen, all of which can reduce iron oxides, even at low temperatures. Besides the thermodynamic and kinetic advantages of a hydrogen plasma, the byproduct of the reaction is water, which does not pose any environmental problems. A review of the theory and practice of iron ore reduction using a hydrogen plasma is presented. The thermodynamic and kinetic aspects are considered, with molecular, atomic and ionic hydrogen considered separately. The importance of vibrationally excited hydrogen molecules in overcoming the activation energy barriers, and in transferring energy to the iron oxide, is emphasized. Both thermal and nonthermal plasmas are considered. The thermophysical properties of hydrogen and argon-hydrogen plasmas are discussed, and their influence on the constriction and flow in the of arc plasmas is considered. The published R&D on hydrogen plasma reduction of iron oxide is reviewed, with both the reduction of molten iron ore and in-flight reduction of iron ore particles being considered. Finally, the technical and economic feasibility of the process are discussed. It is shown that hydrogen plasma processing requires less energy than carbothermic reduction, mainly because pelletization, sintering, and cokemaking are not required. Moreover, the formation of the greenhouse gas CO2 as a byproduct is avoided. In-flight reduction has the potential for a throughput at least equivalent to the blast furnace process. It is concluded that hydrogen plasma reduction of iron ore is a potentially attractive alternative to standard methods.

  9. Testing of adsorbents used in nuclear power plant air cleaning systems using the open-quotes Newclose quotes standards

    International Nuclear Information System (INIS)

    Freeman, W.P.

    1993-01-01

    Ever since the publication of the NRC Information Notice No. 87-32: Deficiencies in the Testing of Nuclear-Grade Activated Charcoal, nuclear power facilities in the US have struggled in their efforts to open-quotes...review the information for applicability to their facilities and consider action, if appropriate ...close quotes as stated in the notice. The encouragement of resident NRC inspectors at some nuclear power facilities has prompted a variety of responses ranging from no change at all in testing requirements to contemplated changes in plant technical specifications. This confusion is the result of a couple factors. The first factor is the lack of a current revision to NRC Regulatory Guide 1.52, the basic document used in nuclear power plant technical specifications for the testing of engineered-safety feature (ESF) post accident air cleaning systems. The second factor is the standards that have been written since the last revision of Reg. Guide 1.52 which include two revision of ANSI N509 and N510, two revisions of RDT M16-1T, two version of ASTM D3803, two versions of ASTM D4069, and three versions of an SME code AG-1. Few of the standards and codes listed above are commensurate with each other and, thus, present a nearly insolvable maze to the HVAC engineer asked to upgrade adsorbent testing requirements following the standards. This paper describes the authors experience with a number of nuclear power facilities in their efforts to meet the requirements of the new standards of testing adsorbents from nuclear power plant air cleaning systems. The existing standards are discussed in light of the current state of the art for adsorbent testing of adsorbent media from nuclear air treatment systems. Test results are presented showing the impact of new test requirements on acceptance criteria when compared to the old test requirements and recommendations are offered for solution of this testing problem in the future. 12 refs., 5 tabs

  10. Selective Electrochemical Generation of Hydrogen Peroxide from Water Oxidation

    DEFF Research Database (Denmark)

    Viswanathan, Venkatasubramanian; Hansen, Heine Anton; Nørskov, Jens K.

    2015-01-01

    evolution and form hydrogen peroxide. Using density functional theory calculations, we show that the free energy of adsorbed OH* can be used to determine selectivity trends between the 2e(-) water oxidation to H2O2 and the 4e(-) oxidation to O2. We show that materials which bind oxygen intermediates...... sufficiently weakly, such as SnO2, can activate hydrogen peroxide evolution. We present a rational design principle for the selectivity in electrochemical water oxidation and identify new material candidates that could perform H2O2 evolution selectively....

  11. Enhanced hydrogen storage by using lithium decoration on phosphorene

    Energy Technology Data Exchange (ETDEWEB)

    Yu, Zhiyuan; Wan, Neng, E-mail: wn@seu.edu.cn, E-mail: lsy@seu.edu.cn; Lei, Shuangying, E-mail: wn@seu.edu.cn, E-mail: lsy@seu.edu.cn; Yu, Hong [Key Laboratory of Microelectromechanical Systems of the Ministry of Education, Southeast University, Nanjing 210096 (China)

    2016-07-14

    The hydrogen storage characteristics of Li decorated phosphorene were systematically investigated based on first-principle density functional theory. It is revealed that the adsorption of H{sub 2} on pristine phosphorene is relatively weak with an adsorption energy of 0.06 eV. While this value can be dramatically enhanced to ∼0.2 eV after the phosphorene was decorated by Li, and each Li atom can adsorb up to three H{sub 2} molecules. The detailed mechanism of the enhanced hydrogen storage was discussed based on our density functional theory calculations. Our studies give a conservative prediction of hydrogen storage capacity to be 4.4 wt. % through Li decoration on pristine phosphorene. By comparing our calculations to the present molecular dynamic simulation results, we expect our adsorption system is stable under room temperature and hydrogen can be released after moderate heating.

  12. Hydrogen production through small capacity water electrolysis systems; Production d'hydrogene par electrolyse de l'eau. Application a des systemes de petite capacite

    Energy Technology Data Exchange (ETDEWEB)

    Schulz, Ph. [TotalFinaElf, la Defense 6, 92 - Courbevoie (France)

    2002-01-01

    Less than 1 % of the world's hydrogen is produced by electrolysis of water, in large plants mainly in connection with hydropower. For users requiring extremely pure hydrogen, electrolysis can be a convenient mean of obtaining the required hydrogen quality, where cheap electricity is available. This paper aims at presenting the latest technical developments of small capacity electrolyzers, that could fuel hydrogen cells or internal combustion engines. (author)

  13. Effects of welding fumes on nuclear air cleaning system carbon adsorber banks

    Energy Technology Data Exchange (ETDEWEB)

    Roberson, P.W. [Duke Power Company, Huntersville, NC (United States)

    1997-08-01

    Standard Technical Specifications for nuclear air cleaning systems include requirements for surveillance tests following fire, painting, or chemical release in areas communicating with the affected system. To conservatively implement this requirement, many plants categorize welding as a chemical release process, and institute controls to ensure that welding fumes do not interact with carbon adsorbers in a filter system. After reviewing research data that indicated welding had a minimal impact on adsorber iodine removal efficiency, further testing was performed with the goal of establishing a welding threshold. It was anticipated that some quantity of weld electrodes could be determined that had a corresponding detrimental impact on iodine removal efficiency for the exposed adsorber. This value could be used to determine a conservative sampling schedule that would allow the station to perform laboratory testing to ensure system degradation did not occur without a full battery of surveillance tests. A series of tests was designed to demonstrate carbon efficiency versus cumulative welding fume exposure. Three series of tests were performed, one for each of three different types of commonly used weld electrodes. Carbon sampling was performed at baseline conditions, and every five pounds of electrode thereafter. Two different laboratory tests were performed for each sample; one in accordance with ASTM 3803/1989 at 95% relative humidity and 30 degrees C, and another using the less rigorous conditions of 70% relative humidity and 80 degrees C. Review of the test data for all three types of electrodes failed to show a significant correlation between carbon efficiency degradation and welding fume exposure. Accordingly, welding is no longer categorized as a `chemical release process` at McGuire Nuclear Station, and limits on welding fume interaction with ventilation systems have been eliminated. 4 refs., 3 figs., 1 tab.

  14. INDOT Technical Training Plan : [Technical Summary

    Science.gov (United States)

    2012-01-01

    A wide range of job classifications, increasing technical : performance expectations, licensing and certification requirements, : budget restrictions and frequent department : reorganization has made technical training of employees : more difficult, ...

  15. Study of the chemisorption and hydrogenation of propylene on platinum by temperature-programed desorption

    Energy Technology Data Exchange (ETDEWEB)

    Tsuchiya, S.; Nakamura, M.; Yoshioka, N.

    1978-01-01

    Temperature-programed desorption (TPD) chromotograms of propylene adsorbed on platinum black in the absence or presence of hydrogen preadsorbed, admitted simultaneously, or admitted later, all showed four peaks at about 260/sup 0/ (A), 380/sup 0/ (B), 570/sup 0/ (C), and higher than 720/sup 0/K (D). Peaks A and B were identified as mixtures of propylene and propane, and peaks C and D were methane formed by thermal decomposition of the chemisorbed propylene during desorption. When nitrogen rather than helium was used as the carrier gas for the TPD, only delta-hydrogen was observed; this suggested that propylene was more strongly adsorbed on the platinum than hydrogen. Studies of the reactivities with propylene of the various types of chemisorbed hydrogen previously detected by TPD showed that propylene reacted with ..gamma..-hydrogen present on the surface in the form of hydrogen atoms chemisorbed on top of platinum atoms and with ..beta..-hydrogen, molecular hydrogen chemisorbed in a bridged form, but did not react with delta-hydrogen. Tables and graph.

  16. A study of the thermostimulated evolution of labelled hydrogen sulfide from the leached basalt fibers

    International Nuclear Information System (INIS)

    Zheleznov, A.V.; Zyuzin, A.Yu.; Bekman, I.N.

    1991-01-01

    Thermostimulated separation of labelled hydrogen sulfide from basalt fibers leached by hydrochloric acid is investigated by the method of radioactive tracers. It is shown that the type of H 2 35 S thermosorption spectrum depends on the presence of water traces in a fibrous adsrobent. Formal order and activation energy of thermodesorption of labelled hydrogen sulfide as well as inhomogeneity of porous structure of adsorbents based on basalt fibers are established

  17. Hydrogen-powered lawn mower: 14 years of operation

    International Nuclear Information System (INIS)

    Yvon, K.; Lorenzoni, J.-L.

    2006-01-01

    Our hydrogen-powered lawn mower [Yvon K, Lorenzoni J-L. Hydrogen powered lawn mower. Int J Hydrogen Energy 1993; 18, 345-48] has been operated without major interruption during the past 14 years. The commercial model was originally running on gasoline and was adapted to hydrogen by making small adjustments to the carburettor and by installing a hydrogen reservoir containing solid-state metal hydrides. During the evaluation period the only maintenance work was changing the lubricating oil of the engine once a year, and reactivating the metal hydride powder by external heating after an accidental inlet of air into the reservoir. There occurred no technical failure, and there was no safety incident, neither during operation nor during recharging of hydrogen. This demonstrates that a hydrogen-operated device of this type is mature for use by greater public. Cost and marketing issues are discussed. (author)

  18. Hydrogen Production Using Nuclear Energy

    Energy Technology Data Exchange (ETDEWEB)

    Verfondern, K. [Research Centre Juelich (Germany)

    2013-03-15

    One of the IAEA's statutory objectives is to 'seek to accelerate and enlarge the contribution of atomic energy to peace, health and prosperity throughout the world.' One way this objective is achieved is through the publication of a range of technical series. Two of these are the IAEA Nuclear Energy Series and the IAEA Safety Standards Series. According to Article III.A.6 of the IAEA Statute, the safety standards establish 'standards of safety for protection of health and minimization of danger to life and property'. The safety standards include the Safety Fundamentals, Safety Requirements and Safety Guides. These standards are written primarily in a regulatory style, and are binding on the IAEA for its own programmes. The principal users are the regulatory bodies in Member States and other national authorities. The IAEA Nuclear Energy Series comprises reports designed to encourage and assist R and D on, and application of, nuclear energy for peaceful uses. This includes practical examples to be used by owners and operators of utilities in Member States, implementing organizations, academia, and government officials, among others. This information is presented in guides, reports on technology status and advances, and best practices for peaceful uses of nuclear energy based on inputs from international experts. The IAEA Nuclear Energy Series complements the IAEA Safety Standards Series. Nuclear generated hydrogen has important potential advantages over other sources that will be considered for a growing hydrogen share in a future world energy economy. Still, there are technical uncertainties in nuclear hydrogen processes that need to be addressed through a vigorous research and development effort. Safety issues as well as hydrogen storage and distribution are important areas of research to be undertaken to support a successful hydrogen economy in the future. The hydrogen economy is gaining higher visibility and stronger political support in several parts of the

  19. TECHNICAL COORDINATION

    CERN Document Server

    A. Ball and W. Zeuner

    2013-01-01

    For the reporting period, the CMS common systems and infrastructure worked well, without failures that caused significant data losses. One more disconnection of the magnet cold box occurred in the shadow of interruptions in data taking, caused by a series of technical faults. The recognition during 2012 that re-connection can only safely be done at around 2 T implies a minimum magnet recovery time of 12 hours and raises serious concerns about the number of ramping cycles of the magnet these incidents cause. This has triggered studies of how to make the cryo-system of the magnet more robust against failures. The proton-proton run ended just before the end-of-year CERN closure, during which CASTOR was installed on the negative end of CMS and both ZDC calorimeters were installed in TAN absorbers the LHC tunnel, in preparation for the heavy-ion run. The installation of CASTOR was an excellent “engineering test” of procedures for working in an activated environment. Despite some technical pr...

  20. TECHNICAL COORDINATION

    CERN Multimedia

    Austin Ball

    Summary of progress since last CMS week. Ten years of construction work have been completed. CMS is closed, in very close to the ideal low luminosity configuration, and performed well in the first tests with LHC beam. Behind this encouraging news is the story of a summer of intense commitment by many teams (from the collaboration and 3 CERN departments) working together, against the clock and despite many minor setbacks, to ensure that the experiment was ready to play a leading role in the excitement of September 10. Following beampipe bakeout and refill with pure neon, a magnificent effort by the ECAL group and the pt 5 technical crew made it possible to install and commission all 4 ECAL endcap Dees before the end of August. In the shadow of this activity, the barrel and forward pixel trackers and part of the beam monitoring were installed within the vac tank. The pt 5 technical teams then succeeded in safely removing the 20t installation tables and their support blocks from beneath the already installed ...

  1. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball and W. Zeuner

    2011-01-01

      Operational experience 2011 CMS is approaching the end of a very successful year of operation. Proton- proton running ended in the late afternoon of 30th October with a stunning 5.73 fb–1 delivered by LHC, of which CMS recorded 5.22 fb–1. During heavy-ion operation, which continues until 7th December, both the accelerator and the CMS detector have also performed very well. Despite the encouraging overall reliability of technical operation, several infrastructure failures which occurred since the last Bulletin are worthy of mention, with one leading for the first time to significant data-loss. On 10th July, a CERN-wide power failure brought down essentially all services including the magnet, due to an MCS setting being left in “manual” after the recent technical stop, but there was no significant damage and the detector was operational before the LHC, despite a slow and tortuous recovery (one of several indications this year that there is room for improve...

  2. Microporous carbonaceous adsorbents for CO2 separation via selective adsorption

    KAUST Repository

    Zhao, Yunfeng

    2015-01-01

    Selective adsorption of CO2 has important implications for many energy and environment-related processes, which require the separation of CO2 from other gases (e.g. N2 and CH4) with high uptakes and selectivity. The development of high-performance adsorbents is one of the most promising solutions to the success of these processes. The present review is focused on the state-of-the-art of carbon-based (carbonaceous) adsorbents, covering microporous inorganic carbons and microporous organic polymers, with emphasis on the correlation between their textural and compositional properties and their CO2 adsorption/separation performance. Special attention is given to the most recently developed materials that were not covered in previous reviews. We summarize various effective strategies (N-doping, surface functionalization, extra-framework ions, molecular design, and pore size engineering) for enhancing the CO2 adsorption capacity and selectivity of carbonaceous adsorbents. Our discussion focuses on CO2/N2 separation and CO2/CH4 separation, while including an introduction to the methods and criteria used for evaluating the performance of the adsorbents. Critical issues and challenges regarding the development of high-performance adsorbents as well as some overlooked facts and misconceptions are also discussed, with the aim of providing important insights into the design of novel carbonaceous porous materials for various selective adsorption based applications. This journal is © The Royal Society of Chemistry.

  3. Adsorption behavior of lithium from seawater using manganese oxide adsorbent

    International Nuclear Information System (INIS)

    Wajima, Takaaki; Munakata, Kenzo; Uda, Tatsuhiko

    2012-01-01

    The deuterium-tritium (D-T) fusion reactor system is expected to provide the main source of electricity in the future. Large amounts of lithium will be required, dependent on the reactor design concept, and alternative resources should be found to provide lithium inventories for nuclear fusion plants. Seawater has recently become an attractive source of this element and the separation and recovery of lithium from seawater by co-precipitation, solvent extraction and adsorption have been investigated. Amongst these techniques, the adsorption method is suitable for recovery of lithium from seawater, because certain inorganic ion-exchange materials, especially spinel-type manganese oxides, show extremely high selectivity for the lithium ion. In this study, we prepared a lithium adsorbent (HMn 2 O 4 ) by elution of spinel-type lithium di-manganese-tetra-oxide (LiMn 2 O 4 ) and examined the kinetics of the adsorbent for lithium ions in seawater using a pseudo-second-order kinetic model. The intermediate, LiMn 2 O 4 , can be synthesized from LiOH·H 2 O and Mn 3 O 4 , from which the lithium adsorbent can subsequently be prepared via acid treatment., The adsorption kinetics become faster and the amount of lithium adsorbed on the adsorbent increases with increasing solution temperature. The thermodynamic values, ΔG 0 , ΔH 0 and ΔS 0 , indicate that adsorption is an endothermic and spontaneous process. (author)

  4. Kinetics of conformational changes of fibronectin adsorbed onto model surfaces.

    Science.gov (United States)

    Baujard-Lamotte, L; Noinville, S; Goubard, F; Marque, P; Pauthe, E

    2008-05-01

    Fibronectin (FN), a large glycoprotein found in body fluids and in the extracellular matrix, plays a key role in numerous cellular behaviours. We investigate FN adsorption onto hydrophilic bare silica and hydrophobic polystyrene (PS) surfaces using Fourier transform infrared spectroscopy-attenuated total reflection (FTIR-ATR) in aqueous medium. Adsorption kinetics using different bulk concentrations of FN were followed for 2h and the surface density of adsorbed FN and its time-dependent conformational changes were determined. When adsorption occurs onto the hydrophilic surface, FN molecules keep their native conformation independent of the adsorption conditions, but the amount of adsorbed FN increases with time and the bulk concentration. Although the protein surface density is the same on the hydrophobic PS surface, this has a strong impact on the average conformation of the adsorbed FN layer. Indeed, interfacial hydration changes induced by adsorption onto the hydrophobic surface lead to a decrease in unhydrated beta-sheet content and cause an increase in hydrated beta-strand and hydrated random domain content of adsorbed FN. This conformational change is mainly dependent on the bulk concentration. Indeed, at low bulk concentrations, the secondary structures of adsorbed FN molecules undergo strong unfolding, allowing an extended and hydrated conformation of the protein. At high bulk concentrations, the molecular packing reduces the unfolding of the stereoregular structures of the FN molecules, preventing stronger spreading of the protein.

  5. Producing hydrogen from coke-oven gas: the Solmer project. [PSA process

    Energy Technology Data Exchange (ETDEWEB)

    Bernard, G; Vidal, J

    1984-05-01

    After presenting the energy situation at the Solmer plant, where coke-oven gas is produced to excess, the authors examine the technical and economic possibilities of utilizing this gas for hydrogen extraction. They describe a project (based on the PSA process) for producing some 65 t/d of hydrogen and present the technical features of the scheme. An evaluation of the energy and financial costs of producing the hydrogen confirms the competitive status of the process.

  6. Revamping of existent chlor-alkali plants for conversion of hydrogen to electricity, hydrogen community germination step

    Energy Technology Data Exchange (ETDEWEB)

    Iordache, Ioan; Laurentiu, Patularu [National R and D Institute for Cryogenics and Isotopic Technologies - ICSI, Rm. Valcea (Romania); Delfrate, Alessandro [UHDENORA SpA (Italy); Iordache, Mihaela [National R and D Institute for Industrial Ecology - ECOIND, Rm. Valcea (Romania)

    2010-07-01

    The transition towards hydrogen becoming widespread in future energy systems and may be one of the greatest social and technical challenges facing society. A wide range of stakeholders will need to work together over extended periods of time to make the sustainable hydrogen ''vision'' a reality. Community-based projects are seen as a route to stimulate the start of the transformation, leading to more widespread early adoption of these new technologies. Valcea have premises to develop some local projects in order to become a Hydrogen Community. This ''Community'' fulfills both an economic-technical background and a scientifically potential. (orig.)

  7. An in situ XPS study of L-cysteine co-adsorbed with water on polycrystalline copper and gold

    Science.gov (United States)

    Jürgensen, Astrid; Raschke, Hannes; Esser, Norbert; Hergenröder, Roland

    2018-03-01

    The interactions of biomolecules with metal surfaces are important because an adsorbed layer of such molecules introduces complex reactive functionality to the substrate. However, studying these interactions is challenging: they usually take place in an aqueous environment, and the structure of the first few monolayers on the surface is of particular interest, as these layers determine most interfacial properties. Ideally, this requires surface sensitive analysis methods that are operated under ambient conditions, for example ambient pressure x-ray photoelectron spectroscopy (AP-XPS). This paper focuses on an AP-XPS study of the interaction of water vapour and l-Cysteine on polycrystalline copper and gold surfaces. Thin films of l-Cysteine were characterized with XPS in UHV and in a water vapour atmosphere (P ≤ 1 mbar): the structure of the adsorbed l-Cysteine layer depended on substrate material and deposition method, and exposure of the surface to water vapour led to the formation of hydrogen bonds between H2O molecules and the COO- and NH2 groups of adsorbed l-Cysteine zwitterions and neutral molecules, respectively. This study also proved that it is possible to investigate monolayers of biomolecules in a gas atmosphere with AP-XPS using a conventional laboratory Al-Kα x-ray source.

  8. Removal of chromium (VI from aqueous medium using chemically modified banana peels as efficient low-cost adsorbent

    Directory of Open Access Journals (Sweden)

    Ashraf Ali

    2016-09-01

    Full Text Available The adsorptive removal of hexavalent chromium Cr(VI from aqueous solutions was investigated by acrylonitrile grafted banana peels (GBPs. Banana peels were treated with 10% HCl, followed by alkaline hydrolysis with 10% NaOH, and washed thoroughly. The bleaching of alkali hydrolyzed peels was carried out with sodium chlorate (NaClO3 in the presence of hydrogen peroxide and glacial acetic acid. The grafting co-polymerization of acrylonitrile onto the bleached pulp was initiated by Fenton’s reagent (Fe+2/H2O2. The optimum conditions for adsorption of Cr(VI were found to be the following: pH 3, adsorbent dose 4 g/L, concentration 400 mg/L and contact time of 120 min. The surface morphology of adsorbent was characterized by scanning electron microscopy (SEM before and after the adsorption. The adsorption of Cr(VI onto grafted banana peels (GBPs was recorded to be 96%. The adsorption data were fully fitted with the Freundlich and Langmuir isotherm model and followed a pseudo-second order kinetic model. Thermodynamic study showed that the adsorption is exothermic and spontaneous. Owing to high efficiency and low cost, grafted banana peels (GBPs can be used as effective adsorbent for Cr(VI removal from wastewater.

  9. Electrochemistry and biosensing reactivity of heme proteins adsorbed on the structure-tailored mesoporous Nb2O5 matrix

    International Nuclear Information System (INIS)

    Xu Xin; Tian Bozhi; Zhang Song; Kong Jilie; Zhao Dongyuan; Liu Baohong

    2004-01-01

    The highly ordered mesoporous niobium oxides fabricated by self-adjusted synthesis have been used as immobilization matrices of heme proteins including Cytochrome c (Cyt C) and horseradish peroxidase (HRP) for their large surface areas, narrow pore size distributions and good biocompatibility. The assembling process was investigated by cyclic voltammetry, amperometry and potential step chronoamperometry in details. Niobium oxide matrices with different structural features were templated with the surfactants and the selectivity of these hosts to specific protein characteristics was determined. It was observed that proteins could be readily assembled onto the mesoporous films with detectable retention of bioactivity. The Nb 2 O 5 matrix with a tailored pore size and counterpoised surface charge to that of hemes allowed for a maximum adsorption capacity of biomolecules. The adsorbed redox molecules exhibited direct electrochemical behavior and gave a pair of well-defined quasi-reversible cyclic voltammetric peaks, indicating that the mesoporous niobium oxide matrix could effectively promote the direct electron transfer between the protein redox site adsorbed and the electrode surface. The midpoint redox potentials of adsorbed Cyt-c and HRP were 14 and -122 mV versus SCE, respectively. Furthermore, the immobilized HRP onto Nb 2 O 5 derived electrode presented good bioactivity and thus was fabricated as an amperometric biosensor for the response of hydrogen peroxide in the range from 0.1 μM to 0.1 mM

  10. Hydrogen converters

    International Nuclear Information System (INIS)

    Mondino, Angel V.

    2003-01-01

    The National Atomic Energy Commission of Argentina developed a process of 99 Mo production from fission, based on irradiation of uranium aluminide targets with thermal neutrons in the RA-3 reactor of the Ezeiza Atomic Centre. These targets are afterwards dissolved in an alkaline solution, with the consequent liberation of hydrogen as the main gaseous residue. This work deals with the use of a first model of metallic converter and a later prototype of glass converter at laboratory scale, adjusted to the requirements and conditions of the specific redox process. Oxidized copper wires were used, which were reduced to elementary copper at 400 C degrees and then regenerated by oxidation with hot air. Details of the bed structure and the operation conditions are also provided. The equipment required for the assembling in cells is minimal and, taking into account the operation final temperature and the purge with nitrogen, the procedure is totally safe. Finally, the results are extrapolated for the design of a converter to be used in a hot cell. (author)

  11. Li-Decorated β12-Borophene as Potential Candidates for Hydrogen Storage: A First-Principle Study.

    Science.gov (United States)

    Liu, Tingting; Chen, Yuhong; Wang, Haifeng; Zhang, Meiling; Yuan, Lihua; Zhang, Cairong

    2017-12-07

    The hydrogen storage properties of pristine β 12 -borophene and Li-decorated β 12 -borophene are systemically investigated by means of first-principles calculations based on density functional theory. The adsorption sites, adsorption energies, electronic structures, and hydrogen storage performance of pristine β 12 -borophene/H₂ and Li- β 12 -borophene/H₂ systems are discussed in detail. The results show that H₂ is dissociated into Two H atoms that are then chemisorbed on β 12 -borophene via strong covalent bonds. Then, we use Li atom to improve the hydrogen storage performance and modify the hydrogen storage capacity of β 12 -borophene. Our numerical calculation shows that Li- β 12 -borophene system can adsorb up to 7 H₂ molecules; while 2Li- β 12 -borophene system can adsorb up to 14 H₂ molecules and the hydrogen storage capacity up to 10.85 wt %.

  12. Hydrogen energy economy: More than utopia

    International Nuclear Information System (INIS)

    Weber, R.

    1992-01-01

    Under the pressure of increasing climate changes in the last years the attitude towards hydrogen technology has changed. Germany has taken a leading position in hydrogen research. Above all there is not only government-sponsored research but also industrial research. It is even assumed that an energy economy on the basis of solar energy as well as of hydrogen is technically possible. If the fact that the total power of all cars in the FRG amounts to 200.000 MW - twice as much as all power stations - is taken into consideration it should be possible to produce in large-scale production decentralized solar or hydrogen energy converters at similar kilowatt rates. (BWI) [de

  13. The future of hydrogen - opportunities and challenges

    International Nuclear Information System (INIS)

    Ball, Michael; Wietschel, Martin

    2009-01-01

    The following article is reproduced from 'The Hydrogen Economy: Opportunities and Challenges', edited by Michael Ball and Martin Wietschel, to be published by Cambridge University Press in June 2009. In the light of ever-increasing global energy use, the increasing cost of energy services, concerns over energy supply security, climate change and local air pollution, this book centres around the question of how growing energy demand for transport can be met in the long term. Given the sustained interest in and controversial discussion of the prospects of hydrogen, the authors highlight the opportunities and the challenges of introducing hydrogen as alternative fuel in the transport sector from an economic, technical and environmental point of view. Through its multi-disciplinary approach the book provides a broad range of researchers, decision makers and policy makers with a solid and wide-ranging knowledge base concerning the hydrogen economy. (author)

  14. Solar driven technologies for hydrogen production

    Directory of Open Access Journals (Sweden)

    Medojević Milovan M.

    2016-01-01

    Full Text Available Bearing in mind that the production of hydrogen based on renewable energy sources, without doubt, is an important aspect to be taken into account when considering the potential of this gas, where as particularly interesting technologies stand out the ones which are based on the use of solar energy to produce hydrogen. The goal of this paper provides basic technological trajectories, with the possibility of combining, for solar driven hydrogen production, such as: electrochemical, photochemical and thermochemical process. Furthermore, the paper presents an analysis of those technologies from a technical as well as economic point of view. In addition, the paper aims to draw attention to the fact that the generation of hydrogen using renewable energy should be imposed as a logical and proper way to store solar energy in the form of chemical energy.

  15. Direct observation and modelling of ordered hydrogen adsorption and catalyzed ortho-para conversion on ETS-10 titanosilicate material.

    Science.gov (United States)

    Ricchiardi, Gabriele; Vitillo, Jenny G; Cocina, Donato; Gribov, Evgueni N; Zecchina, Adriano

    2007-06-07

    Hydrogen physisorption on porous high surface materials is investigated for the purpose of hydrogen storage and hydrogen separation, because of its simplicity and intrinsic reversibility. For these purposes, the understanding of the binding of dihydrogen to materials, of the structure of the adsorbed phase and of the ortho-para conversion during thermal and pressure cycles are crucial for the development of new hydrogen adsorbents. We report the direct observation by IR spectroscopic methods of structured hydrogen adsorption on a porous titanosilicate (ETS-10), with resolution of the kinetics of the ortho-para transition, and an interpretation of the structure of the adsorbed phase based on classical atomistic simulations. Distinct infrared signals of o- and p-H2 in different adsorbed states are measured, and the conversion of o- to p-H2 is monitored over a timescale of hours, indicating the presence of a catalyzed reaction. Hydrogen adsorption occurs in three different regimes characterized by well separated IR manifestations: at low pressures ordered 1:1 adducts with Na and K ions exposed in the channels of the material are formed, which gradually convert into ordered 2:1 adducts. Further addition of H2 occurs only through the formation of a disordered condensed phase. The binding enthalpy of the Na+-H2 1:1 adduct is of -8.7+/-0.1 kJ mol(-1), as measured spectroscopically. Modeling of the weak interaction of H2 with the materials requires an accurate force field with a precise description of both dispersion and electrostatics. A novel three body force field for molecular hydrogen is presented, based on the fitting of an accurate PES for the H2-H2 interaction to the experimental dipole polarizability and quadrupole moment. Molecular mechanics simulations of hydrogen adsorption at different coverages confirm the three regimes of adsorption and the structure of the adsorbed phase.

  16. Factors determining the activity of catalysts of various chemical types in the oxidation of hydrogen. I. Oxidation and isotope exchange of hydrogen on cobalt monoxide-oxide

    International Nuclear Information System (INIS)

    Polgikh, L.Y.; Golodets, G.I.; Il'chenko, N.I.

    1985-01-01

    On the basis of data on the kinetics of the reaction 2H 2 + O 2 = 2H 2 O isotope exchange H 2 + D 2 = 2HD under the conditions of oxidative catalysis, and the kinetic isotope effect, a mechanism is proposed for the oxidation of hydrogen on cobalt monoxide-oxide. At low temperatures the reaction proceeds according to a mechanism of alternating reduction-reoxidation of the surface with the participation of hydrogen adsorbed in molecular form; at increased temperature and low P 02 /P /SUB H2/ ratios, a significant contribution to the observed rate is made by a mechanism including dissociative chemisorption of hydrogen

  17. Quantitative relationship between adsorbed amount of solute and solvent composition

    International Nuclear Information System (INIS)

    Wang Yan; Geng Xindu; Zebolsky, Don M.

    2003-01-01

    A new adsorption isotherm that relates the amount of solute adsorbed to the solvent concentration is proposed. The new equation is derived from Geng and Shi's stoichiometric displacement model for adsorption (SDM-A). The obtained equation may be simplified to an expression containing two parameters. The equation with two parameters, valid for low concentrations of solute, is a logarithmically linear relationship. The intercept contains a thermodynamic equilibrium constant of the solute displacing solvent from the adsorbent. The slope is the negative value of the stoichiometric displacement parameter (Z), the average total number of solvent molecules displaced from an active site on the adsorbent and from the solute. Tests with a homologous series of aromatic alcohols by frontal analysis in reversed phase liquid chromatography demonstrate that experimental results fit the equation well

  18. Lotus Dust Mitigation Coating and Molecular Adsorber Coating

    Science.gov (United States)

    O'Connor, Kenneth M.; Abraham, Nithin S.

    2015-01-01

    NASA Goddard Space Flight Center has developed two unique coating formulations that will keep surfaces clean and sanitary and contain contaminants.The Lotus Dust Mitigation Coating, modeled after the self-cleaning, water-repellant lotus leaf, disallows buildup of dust, dirt, water, and more on surfaces. This coating, has been successfully tested on painted, aluminum, glass, silica, and some composite surfaces, could aid in keeping medical assets clean.The Molecular Adsorber Coating is a zeolite-based, sprayable molecular adsorber coating, designed to prevent outgassing in materials in vacuums. The coating works well to adsorb volatiles and contaminates in manufacturing and processing, such as in pharmaceutical production. The addition of a biocide would also aid in controlling bacteria levels.

  19. Interaction of Hydrogen with MOF-5.

    Science.gov (United States)

    Bordiga, Silvia; Vitillo, Jenny G; Ricchiardi, Gabriele; Regli, Laura; Cocina, Donato; Zecchina, Adriano; Arstad, Bjørnar; Bjørgen, Morten; Hafizovic, Jasmina; Lillerud, Karl Petter

    2005-10-06

    Hydrogen storage is among the most demanding challenges in the hydrogen-based energy cycle. One proposed strategy for hydrogen storage is based on physisorption on high surface area solids such as metal-organic frameworks (MOFs). Within this class of materials, MOF-5 has been the first structure studied for hydrogen storage. The IR spectroscopy of adsorbed H2 performed at 15 K and ab initio calculations show that the adsorptive properties of this material are mainly due to dispersive interactions with the internal wall structure and to weak electrostatic forces associated with O13Zn4 clusters. Calculated and measured binding enthalpies are between 2.26 and 3.5 kJ/mol, in agreement with the H2 rotational barriers reported in the literature. A minority of binding sites with higher adsorption enthalpy (7.4 kJ/mol) is also observed. These species are probably associated with OH groups on the external surfaces present as termini of the microcrystals.

  20. Zero emission distributed hydrogen production

    International Nuclear Information System (INIS)

    Maddaloni, J.; Rowe, A.; Bailey, R.; McDonald, J.D.

    2004-01-01

    The need for distributed production facilities has become a critical issue in developing a hydrogen infrastructure. Hydrogen generation using processes that make effective use of what would normally be considered waste streams or process inefficiencies can have more favorable economics than stand-alone technologies. Currently, natural gas is distributed to industrial and residential customers through a network of pipelines. High pressure main lines move gas to the vicinity of consumers where the pressure is reduced for local, low pressure distribution. Often, the practice is to use an isenthalpic expansion which results in a cooling of the gas stream. Some of the natural gas is burned to preheat the fuel so that the temperature after the expansion is near ambient. This results in the destruction of exergy in the high pressure gas stream and produces CO 2 in the process. If, instead, a turbo-expander is used to reduce the stream pressure, work can be recovered using a generator and hydrogen can be produced via electrolysis. This method of hydrogen production is free of green-house gas emissions, makes use of existing gas distribution facilities, and uses exergy that would otherwise be destroyed. Pressure reduction using the work producing process (turbo-expander) is accompanied by a large drop in temperature, on the average of 70 K. The local gas distributor requires the gas temperature to be raised again to near 8 o C to prevent damage to valve assemblies. The required heating power after expansion can be on the order of megawatts (site dependent.) Supplying the heat can be seen as a cost if energy is taken from the system to reheat the fuel; however, the low temperature stream may also be considered an asset if the cooling power can be used for a local process. This analysis is the second stage of a study to examine the technical and economic feasibility of using pressure let-down sites as hydrogen production facilities. This paper describes a proposed

  1. Technical presentation

    CERN Multimedia

    GS Department

    2010-01-01

    10 March 2010 DYNEOS 10:00 – 12:00 - Main Building, Room B, 61-1-009 Dyneos AG is active in the fields of photonics, laser and high-precision positioning. Our highly qualified engineer team has more than 30 years of experience in electro-optical solutions sales. The engineers are supported by a technical and administrative team. We are focused on the Swiss market and represent six suppliers (Coherent, PI Physik Instrumente, SIOS, Nanonics Imaging, APE, Ekspla) in order to give a qualified sales and service support to our customers. Our products are dedicated to the research field as well as to industry. In addition to standard catalog products, we offer custom designs to fulfill the specific needs of OEM customers or specific applications.

  2. Technical presentation

    CERN Document Server

    FP Department

    2009-01-01

    07 April 2009 Technical presentation by Leuze Electronics: 14.00 – 15.00, Main Building, Room 61-1-017 (Room A) Photoelectric sensors, data identification and transmission systems, image processing systems. We at Leuze Electronics are "the sensor people": we have been specialising in optoelectronic sensors and safety technology for accident prevention for over 40 years. Our dedicated staff are all highly customer oriented. Customers of Leuze Electronics can always rely on one thing – on us! •\tFounded in 1963 •\t740 employees •\t115 MEUR turnover •\t20 subsidiaries •\t3 production facilities in southern Germany Product groups: •\tPhotoelectric sensors •\tIdentification and measurements •\tSafety devices

  3. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball and W. Zeuner

    2010-01-01

    Overview Once again, the bulk of this article reviews the intense activity of a recently completed shutdown, which, although quite unforeseeable until a few weeks before it started, proved by its success that our often advertised capability to conduct major maintenance within a two month period is real. Although safely completed, on-time to remarkable precision, the activity was not without incident, and highlighted our dependence on many experienced, specialist teams and their precise choreography. Even after the yoke was safely closed, magnet re-commissioning and beampipe pumpdown showed new and thought-provoking behaviour. The struggle to maintain adequate technical resources will be a pre-occupation over the coming months, in parallel with the start of truly sustained operation, for which various procedures are still being put in place. Planning for future shutdowns must now become a high priority, with many working groups and task forces already in existence to prepare infrastructure improvements and to...

  4. Technical presentation

    CERN Document Server

    FI Department

    2008-01-01

    RADIOSPARES, the leading catalogue distributor of components (electronic, electrical, automation, etc.) and industrial supplies will be at CERN on Friday 3 October 2008 (Main Building, Room B, from 9.00 a.m. to 3.00 p.m.) to introduce its new 2008/2009 catalogue. This will be the opportunity for us to present our complete range of products in more detail: 400 000 part numbers available on our web site (Radiospares France, RS International, extended range of components from other manufacturers); our new services: quotations, search for products not included in the catalogue, SBP products (Small Batch Production: packaging in quantities adapted to customers’ requirements); partnership with our focus manufacturers; demonstration of the on-line purchasing tool implemented on our web site in conjunction with CERN. RADIOSPARES will be accompanied by representatives of FLUKE and TYCO ELECTRONICS, who will make presentations, demonstrate materials and answer any technical questio...

  5. Heat transfer between adsorbate and laser-heated hot electrons

    International Nuclear Information System (INIS)

    Ueba, H; Persson, B N J

    2008-01-01

    Strong short laser pulses can give rise to a strong increase in the electronic temperature at metal surfaces. Energy transfer from the hot electrons to adsorbed molecules may result in adsorbate reactions, e.g. desorption or diffusion. We point out the limitations of an often used equation to describe the heat transfer process in terms of a friction coupling. We propose a simple theory for the energy transfer between the adsorbate and hot electrons using a newly introduced heat transfer coefficient, which depends on the adsorbate temperature. We calculate the transient adsorbate temperature and the reaction yield for a Morse potential as a function of the laser fluency. The results are compared to those obtained using a conventional heat transfer equation with temperature-independent friction. It is found that our equation of energy (heat) transfer gives a significantly lower adsorbate peak temperature, which results in a large modification of the reaction yield. We also consider the heat transfer between different vibrational modes excited by hot electrons. This mode coupling provides indirect heating of the vibrational temperature in addition to the direct heating by hot electrons. The formula of heat transfer through linear mode-mode coupling of two harmonic oscillators is applied to the recent time-resolved study of carbon monoxide and atomic oxygen hopping on an ultrafast laser-heated Pt(111) surface. It is found that the maximum temperature of the frustrated translation mode can reach high temperatures for hopping, even when direct friction coupling to the hot electrons is not strong enough

  6. SAPO-34 coated adsorbent heat exchanger for adsorption chillers

    International Nuclear Information System (INIS)

    Freni, Angelo; Bonaccorsi, Lucio; Calabrese, Luigi; Caprì, Angela; Frazzica, Andrea; Sapienza, Alessio

    2015-01-01

    In this work, adsorbent coatings on aluminum surfaces were prepared by dip-coating method starting from a water suspension of SAPO-34 zeolite and a silane-based binder. Silane-zeolite coatings morphology and surface coverage grade were evaluated by scanning electron microscopy. Adhesive and mechanical properties were evaluated by peel, pull-off, impact and micro-hardness tests, confirming the good interaction between metal substrate, binder and zeolite. Adsorption equilibrium and kinetics of water vapour adsorption on the adsorbent coating were studied in the range T = 30–150 °C and pH 2 O = 11 mbar using a CAHN 2000 thermo-balance. It was found that, in the investigated conditions, the organic binder doesn't affect the water adsorption capacity and adsorption kinetics of the original SAPO-34 zeolite. Subsequently, the zeolite coating was applied on a finned flat-tubes aluminum heat exchanger realizing a full-scale AdHEx with an uniform adsorbent coating 0.1 mm thick and a metal/adsorbent mass ratio = 6. The cooling capacity of the realized coated AdHEx was measured by a lab-scale adsorption chiller under realistic operating conditions for air conditioning applications. The coated AdHEx produced up to 675 W/kg ads specific cooling power with a cycle time of 5 min. Adsorption stability of the coated adsorber subjected to 600 sorption cycles was successfully verified. - Highlights: • Adsorbent coatings on aluminum surfaces were prepared by dip-coating method. • Silane-zeolite coatings morphology, and mechanical properties were studied. • The zeolite coating was applied on a finned flat-tubes aluminum heat exchanger. • The coated AdHEx was tested in a lab scale adsorption chiller

  7. On the Role of Surface Modifications of Palladium Catalysts in the Selective Hydrogenation of Acetylene

    DEFF Research Database (Denmark)

    Studt, Felix; Abild-Pedersen, Frank; Bligaard, Thomas

    2008-01-01

    Summing Me up: DFT calculations have shown that alloying, subsurface carbon, and hydride formation, all increase the selectivity of Pd catalysts for acetylene hydrogenation by weakening the surface–adsorbate bond. A simple descriptor—the adsorption energy of a methyl group—has been used to quanti...

  8. Technical Training: Technical Training Seminar

    CERN Multimedia

    2004-01-01

    TECHNICAL TRAINING Monique Duval tel. 74924 technical.training@cern.ch Tuesday 3 February 2004 From 09:00 to 13:30 - Training Centre Auditorium - bldg. 593, room 11 USB (Universal Serial Bus) CYPRESS Seminar Claudia Colombini, Field Application Engineer CYPRESS ActiveComp Electronic GmbH D-85077 MANCHING, Germany As a pioneer in USB, CYPRESS sets the standard for cost-effective solutions without sacrificing functionality, performance or reliability. Having shipped over 200 million USB devices, Cypress is the undisputed market leader and demonstrates unmatched USB expertise. With the industry's broadest selection of USB solutions, Cypress has the right silicon, software and support for every USB application, from Low-speed to High-Speed and USB On-The-Go (OTG). 9:00 - 10:30 Overview of USB systems. USB CYPRESS product overview. Peripherals: Low Speed, Full Speed, High Speed (1.1 and 2.0). Hub Solutions, Embedded Host Solutions, On-The-Go (OTG) and wireless USB. USB Development Tools (first part) 10:30 -...

  9. Hydrogen Production Cost Estimate Using Biomass Gasification: Independent Review

    Energy Technology Data Exchange (ETDEWEB)

    Ruth, M.

    2011-10-01

    This independent review is the conclusion arrived at from data collection, document reviews, interviews and deliberation from December 2010 through April 2011 and the technical potential of Hydrogen Production Cost Estimate Using Biomass Gasification. The Panel reviewed the current H2A case (Version 2.12, Case 01D) for hydrogen production via biomass gasification and identified four principal components of hydrogen levelized cost: CapEx; feedstock costs; project financing structure; efficiency/hydrogen yield. The panel reexamined the assumptions around these components and arrived at new estimates and approaches that better reflect the current technology and business environments.

  10. Surface characterization of adsorbed asphaltene on a stainless steel surface

    International Nuclear Information System (INIS)

    Abdallah, W.A.; Taylor, S.D.

    2007-01-01

    X-ray photoelectron spectroscopy was used to characterize a single layer of adsorbed asphaltene on a metallic surface. The deposits were created by immersing a stainless steel disc into a dilute asphaltene solution with either toluene or dichloromethane as the solvent, although the toluene solution allowed for better control of the adsorbed asphaltene layer and less atmospheric oxygen contamination. The analyses for C 1s, S 2p 3/2 , N 1s and O 1s photoemission peaks indicated that different functional groups are present in the asphaltene layer including carboxylic, pyrrolic, pyridininc, thiophenic and sulfite, with slight differences in their binding energies

  11. Adsorbates in a Box: Titration of Substrate Electronic States

    Science.gov (United States)

    Cheng, Zhihai; Wyrick, Jonathan; Luo, Miaomiao; Sun, Dezheng; Kim, Daeho; Zhu, Yeming; Lu, Wenhao; Kim, Kwangmoo; Einstein, T. L.; Bartels, Ludwig

    2010-08-01

    Nanoscale confinement of adsorbed CO molecules in an anthraquinone network on Cu(111) with a pore size of ≈4nm arranges the CO molecules in a shell structure that coincides with the distribution of substrate confined electronic states. Molecules occupy the states approximately in the sequence of rising electron energy. Despite the sixfold symmetry of the pore boundary itself, the adsorbate distribution adopts the threefold symmetry of the network-substrate system, highlighting the importance of the substrate even for such quasi-free-electron systems.

  12. Longitudinal dispersion coefficient depending on superficial velocity of hydrogen isotopes flowing in column packed with zeolite pellets at 77.4 K

    Energy Technology Data Exchange (ETDEWEB)

    Kotoh, K. [Faculty of Engineering, Kyushu University, Nishi-ku, Fukuoka (Japan); Graduate School of Engineering, Kyushu University, Nishi-ku, Fukuoka (Japan); Kubo, K.; Takashima, S.; Moriyama, S.T. [Graduate School of Engineering, Kyushu University, Nishi-ku, Fukuoka (Japan); Tanaka, M. [National Institute for Fusion Science, Oroshi-cho, Toki, Gifu (Japan); Sugiyama, T. [Faculty of Engineering, Nagoya University, Furo-cho, Chikusa-ku, Nagoya (Japan)

    2015-03-15

    Authors have been developing a cryogenic pressure swing adsorption system for hydrogen isotope separation. In the problem of its design and operation, it is necessary to predict the concentration profiles developing in packed beds of adsorbent pellets. The profiling is affected by the longitudinal dispersion of gas flowing in packed beds, in addition to the mass transfer resistance in porous media of adsorbent pellets. In this work, an equation is derived for estimating the packed-bed dispersion coefficient of hydrogen isotopes, by analyzing the breakthrough curves of trace D{sub 2} or HD replacing H{sub 2} adsorbed in synthetic zeolite particles packed columns at the liquefied nitrogen temperature 77.4 K. Since specialized for hydrogen isotopes, this equation can be considered to estimate the dispersion coefficients more reliable for the cryogenic hydrogen isotope adsorption process, than the existing equations. (authors)

  13. Electric arc hydrogen heaters

    International Nuclear Information System (INIS)

    Zasypin, I.M.

    2000-01-01

    The experimental data on the electric arc burning in hydrogen are presented. Empirical and semiempirical dependences for calculating the arc characteristics are derived. An engineering method of calculating plasma torches for hydrogen heating is proposed. A model of interaction of a hydrogen arc with a gas flow is outlined. The characteristics of plasma torches for heating hydrogen and hydrogen-bearing gases are described. (author)

  14. Evaluation of Nuclear Hydrogen Production System

    International Nuclear Information System (INIS)

    Park, Won Seok; Park, C. K.; Park, J. K. and others

    2006-04-01

    The major objective of this work is tow-fold: one is to develop a methodology to determine the best VHTR types for the nuclear hydrogen demonstration project and the other is to evaluate the various hydrogen production methods in terms of the technical feasibility and the effectiveness for the optimization of the nuclear hydrogen system. Both top-tier requirements and design requirements have been defined for the nuclear hydrogen system. For the determination of the VHTR type, a comparative study on the reference reactors, PBR and PBR, was conducted. Based on the analytic hierarchy process (AHP) method, a systematic methodology has been developed to compare the two VHTR types. Another scheme to determine the minimum reactor power was developed as well. Regarding the hydrogen production methods, comparison indices were defined and they were applied to the IS (Iodine-Sulfur) scheme, Westinghouse process, and the, high-temperature electrolysis method. For the HTE, IS, and MMI cycle, the thermal efficiency of hydrogen production were systematically evaluated. For the IS cycle, an overall process was identified and the functionality of some key components was identified. The economy of the nuclear hydrogen was evaluated, relative to various primary energy including natural gas coal, grid-electricity, and renewable. For the international collaborations, two joint research centers were established: NH-JRC between Korea and China and NH-JDC between Korea and US. Currently, several joint researches are underway through the research centers

  15. Manitoba: path to a hydrogen future

    International Nuclear Information System (INIS)

    Parsons, R.V.; Crone, J.

    2003-01-01

    A hydrogen economy is not just about future clean energy but is also about future economic development. It is about new products, new services, new knowledge, and renewable energy sources that will be ultimately used by consumers in the future, and thus represent potential new economic opportunities. The concept of achieving important environmental and health goals through a cleaner energy economy, based on hydrogen, is not new. Similarly, the desire of individual jurisdictions to seek out and develop economic development opportunities is not new. The key question today becomes one of how to plot directions on hydrogen that will yield appropriate economic development gains in the future. While hydrogen offers significant promise, the prospect benefits are recognized to be still largely long-term in nature. In addition, the ability to identify appropriate future directions is clouded by a degree of 'hydrogen hype' and by a variety of major technical and market uncertainties. During 2002, a unique process was initiated within Manitoba combining these elements to work toward a Hydrogen Economic Development Strategy, a strategy that is ultimately intended to lead the province as a whole to determining our future economic niches for hydrogen. This paper describes the nature of the assessment process undertaken within Manitoba, the outcomes achieved and general insights of relevance to a broader audience. (author)

  16. Relative efficiency of hydrogen technologies for the hydrogen economy : a fuzzy AHP/DEA hybrid model approach

    International Nuclear Information System (INIS)

    Lee, S.

    2009-01-01

    As a provider of national energy security, the Korean Institute of Energy Research is seeking to establish a long term strategic technology roadmap for a hydrogen-based economy. This paper addressed 5 criteria regarding the strategy, notably economic impact, commercial potential, inner capacity, technical spinoff, and development cost. The fuzzy AHP and DEA hybrid model were used in a two-stage multi-criteria decision making approach to evaluate the relative efficiency of hydrogen technologies for the hydrogen economy. The fuzzy analytic hierarchy process reflects the uncertainty of human thoughts with interval values instead of clear-cut numbers. It therefore allocates the relative importance of 4 criteria, notably economic impact, commercial potential, inner capacity and technical spin-off. The relative efficiency of hydrogen technologies for the hydrogen economy can be measured via data envelopment analysis. It was concluded that the scientific decision making approach can be used effectively to allocate research and development resources and activities

  17. Relative efficiency of hydrogen technologies for the hydrogen economy : a fuzzy AHP/DEA hybrid model approach

    Energy Technology Data Exchange (ETDEWEB)

    Lee, S. [Korea Inst. of Energy Research, Daejeon (Korea, Republic of). Energy Policy Research Division; Mogi, G. [Tokyo Univ., (Japan). Dept. of Technology Management for Innovation, Graduate School of Engineering; Kim, J. [Korea Inst. of Energy Research, Daejeon (Korea, Republic of)

    2009-07-01

    As a provider of national energy security, the Korean Institute of Energy Research is seeking to establish a long term strategic technology roadmap for a hydrogen-based economy. This paper addressed 5 criteria regarding the strategy, notably economic impact, commercial potential, inner capacity, technical spinoff, and development cost. The fuzzy AHP and DEA hybrid model were used in a two-stage multi-criteria decision making approach to evaluate the relative efficiency of hydrogen technologies for the hydrogen economy. The fuzzy analytic hierarchy process reflects the uncertainty of human thoughts with interval values instead of clear-cut numbers. It therefore allocates the relative importance of 4 criteria, notably economic impact, commercial potential, inner capacity and technical spin-off. The relative efficiency of hydrogen technologies for the hydrogen economy can be measured via data envelopment analysis. It was concluded that the scientific decision making approach can be used effectively to allocate research and development resources and activities.

  18. A national inventory of greenhouse gas (GHG), criteria air contaminants (CAC) and hydrogen sulphide (H2S) emissions by the upstream oil and gas industry : volume 1, overview of the GHG emissions inventory : technical report

    International Nuclear Information System (INIS)

    2004-09-01

    A detailed inventory of greenhouse gas (GHG) emissions from the upstream oil and gas sector in Canada was presented along with explanations of the methodologies and data sources used. This report is based on previous work done on methane and volatile organic compound emissions from the upstream oil and gas sector for the period of 1990 to 1995, but it includes key improvements in identifying primary types of emissions sources such as emissions from fuel combustion, flaring, venting, fugitive equipment leaks and accidental releases. It also includes criteria air contaminants and hydrogen sulfide emissions, an analysis of GHG emission intensities and a change in the definition of volatile organic compounds from comprising all non-methane hydrocarbons to comprising all non-methane and non-ethane hydrocarbons. The report covers portions of the upstream oil and gas industry in Canada plus the natural gas transmission and natural gas distribution industries with reference to well drilling, oil production, and natural gas production, processing, transmission and distribution. Accidents and equipment failures are also included. The report reveals the total GHG emissions by source type, sub-sector, facility type and sub-type for the year 2000 at the national level. In 2000, the total carbon dioxide equivalent GHG emissions from the entire oil and gas sector were 101,211 kilo tonnes. For the upstream oil and gas sector alone, total GHG emissions were 84,355 kilo tonnes, representing 12 per cent of Canada's total national emissions of GHGs in 2000. This is an increase of about 25 per cent from 1995 levels. The biggest primary source of these emissions is fuel combustion, which accounts for 40.8 per cent of the total. This report also includes a provincial breakdown of GHG emissions for the natural gas transmission, storage and distribution sub-sectors in Canada for the year 2000. refs., tabs., figs

  19. Solar and Hydrogen

    International Nuclear Information System (INIS)

    Kadirgan, F.; Beyhan, S.; Oezenler, S.

    2006-01-01

    developments allowing wide spread commercialisation of this technology are more likely to come from improvements in the central PEMFC components. Currently, there are two major obstacles inhibiting the application of PEMFC namely, the low activity of anode catalysts and the phenomenon of methanol crossover through the polymer electrolyte membrane from the anode to cathode side. Efforts have been expended in developing new anode catalysts and, to some extend, methanol impermeable membranes.This paper reviews the choice of materials and main methods of manufacture of photovoltaic solar cells, modules, spectrally selective surfaces, and PEMFC components that are commercially available. The research and development works on solar and hydrogen energy systems including PEMFC components made in Istanbul Technical University also will be given.

  20. IEA Hydrogen Implementing Agreement's Second Generation R and D and the Hydrogen Economy

    Energy Technology Data Exchange (ETDEWEB)

    Beck, N.; Garcia-Conde, A. G.; Riis, T. U.; Luzzi, A.; Valladares, M. R. de

    2005-07-01

    join the HIA soon. This paper and presentation will inform the audience about the HIA, recent advances in its collaborative R and D program as well as its future plans. Learn how the HIA, the premier global resource for technical expertise in hydrogen R and D, will contribute to the coming hydrogen economy and how you can benefit from participation in the HIA. (Author)

  1. Generalized model development for a cryo-adsorber and 1-D results for the isobaric refueling period

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, V. Senthil [India Science Lab, General Motors Global R and D, Creator Building, International Technology Park, Bangalore 560066 (India); Kumar, Sudarshan [Chemical Sciences and Material Systems Lab, General Motors Global R and D, Warren Technical Center Campus, 30500 Mound Road, Warren, MI 48090 (United States)

    2010-04-15

    We have developed 3-D model equations for a cryo-adsorption hydrogen storage tank, where the energy balance accommodates the temperature and pressure variation of all the thermodynamic properties. We then reduce the 3-D model to the 1-D isobaric system and study the isobaric refueling period, for simplified geometry and charging conditions. The hydrogen capacity evolution predicted by the 1-D axial bed model is significantly different than that predicted by the lumped-parameter model because of the presence of sharp temperature gradients during refueling. The 1-D model predicts a higher hydrogen capacity than the lumped-parameter model. This observation can be rationalized by the fact that a bed with temperature gradients on equilibration should desorb gas, whenever the adsorbed phase entropy is lower than the gas phase entropy. The 1-D analysis of the isobaric refueling period does not show any significant difference in hydrogen capacity evolution among the axial, single and multicartridge annular bed designs. Hence, a multicartridge annular design, though giving a slightly lower pressure drop, does not offer any heat and mass transfer enhancement over the single cartridge design. And, the single cartridge annular design appears to be optimal. (author)

  2. Effects of basic nitrogen poisoning on adsorption of hydrogen on a hydrotreatment catalyst

    International Nuclear Information System (INIS)

    Entz, R.W.; Seapan, M.

    1985-01-01

    Activity of a hydrotreatment catalyst depends on the hydrogen adsorption characteristics of the catalyst. In this work, the adsorption of hydrogen on a Ni-Mo/Al/sub 2/O/sub 3/ catalyst (shell 324) has been studied using a TGA at 1 atm pressure and 200-400 0 C temperature. Hydrogen adsorption on a calcined catalyst was shown to be of activated type with a sudden increase in hydrogen adsorption around 350 0 C. When the catalyst is extracted with Tetrahydrofuran (THF), the hydrogen adsorption increases gradually as the temperature is increased, approaching a monolayer coverage of the catalyst surface. It is shown that solvent extraction of catalyst changes its hydrogen adsorption characteristics significantly. Indeed, at 400 0 C, an extracted catalyst adsorbs about four times more hydrogen than an unextracted catalyst. Adsorption of basic nitrogen compounds on the catalyst interferes with the hydrogen adsorption. The adsorption of pyridine, piperidine, n-pentylamine, and ammonia were studied at 400 0 C. It is shown that the strength of adsorption of piperidine and n-pentylamine are relatively similar, however their adsorption strength is higher than pyridine. Ammonia is the weakest adsorbing compound studied. These observations are in agreement with other studies

  3. Microscale Enhancement of Heat and Mass Transfer for Hydrogen Energy Storage

    Energy Technology Data Exchange (ETDEWEB)

    Drost, Kevin [Oregon State Univ., Corvallis, OR (United States); Jovanovic, Goran [Oregon State Univ., Corvallis, OR (United States); Paul, Brian [Oregon State Univ., Corvallis, OR (United States)

    2015-09-30

    The document summarized the technical progress associated with OSU’s involvement in the Hydrogen Storage Engineering Center of Excellence. OSU focused on the development of microscale enhancement technologies for improving heat and mass transfer in automotive hydrogen storage systems. OSU’s key contributions included the development of an extremely compact microchannel combustion system for discharging hydrogen storage systems and a thermal management system for adsorption based hydrogen storage using microchannel cooling (the Modular Adsorption Tank Insert or MATI).

  4. Bio-inspired co-catalysts bonded to a silicon photocathode for solar hydrogen evolution

    DEFF Research Database (Denmark)

    Hou, Yidong; Abrams, Billie; Vesborg, Peter Christian Kjærgaard

    2011-01-01

    The production of fuels directly or indirectly from sunlight represents one of the major challenges to the development of a sustainable energy system. Hydrogen is the simplest fuel to produce and while platinum and other noble metals are efficient catalysts for photoelectrochemical hydrogen...... at the reversible potential match the requirement of a photoelectrochemical hydrogen production system with a solar-to-hydrogen efficiency in excess of 10%. The experimental observations are supported by DFT calculations of the Mo3S4 cluster adsorbed on the hydrogen-terminated silicon surface providing insights...... deposited on various supports. It will be demonstrated how this overpotential can be eliminated by depositing the same type of hydrogen evolution catalyst on p-type Si which can harvest the red part of the solar spectrum. Such a system could constitute the cathode part of a tandem dream device where the red...

  5. To the problem of structural materials serviceability in nitrogen-hydrogen-containing environments

    International Nuclear Information System (INIS)

    Bichuya, A.L.

    1982-01-01

    The analysis of the factors which affect high-temperature serviceability of structural materials in nitrogen-hydrogen-containing environments, in particular in ammonia, has been carried out on the basis of the published and own experimental data. It is shown that the observed reduction of serviceability of structural materials, under the effect of high temperatures and nitrogen-hydrogen-containing environments, can occur as a result of corrosion failure connected with nitriding, and also hydrogen embrittlement appearing as a result of the penetration of hydrogen formed during adsorbed gaseous phase dissociation on the metal being deformed. The suggested scheme of high-temperature metal fracture under the effect of nitrogen-hydrogen-containing environments, that in contrast to the previous ones includes the factor of hydrogen ebrittlement, allows to give a real estimation of structional materials serviceability under product service conditions

  6. Chemical hydrogen storage material property guidelines for automotive applications

    Science.gov (United States)

    Semelsberger, Troy A.; Brooks, Kriston P.

    2015-04-01

    Chemical hydrogen storage is the sought after hydrogen storage media for automotive applications because of the expected low pressure operation (0.05 kg H2/kgsystem), and system volumetric capacities (>0.05 kg H2/Lsystem). Currently, the primary shortcomings of chemical hydrogen storage are regeneration efficiency, fuel cost and fuel phase (i.e., solid or slurry phase). Understanding the required material properties to meet the DOE Technical Targets for Onboard Hydrogen Storage Systems is a critical knowledge gap in the hydrogen storage research community. This study presents a set of fluid-phase chemical hydrogen storage material property guidelines for automotive applications meeting the 2017 DOE technical targets. Viable material properties were determined using a boiler-plate automotive system design. The fluid-phase chemical hydrogen storage media considered in this study were neat liquids, solutions, and non-settling homogeneous slurries. Material properties examined include kinetics, heats of reaction, fuel-cell impurities, gravimetric and volumetric hydrogen storage capacities, and regeneration efficiency. The material properties, although not exhaustive, are an essential first step in identifying viable chemical hydrogen storage material properties-and most important, their implications on system mass, system volume and system performance.

  7. Why hydrogen; Pourquoi l'hydrogene?

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2004-02-01

    The energy consumption increase and the associated environmental risks, led to develop new energy sources. The authors present the potentialities of the hydrogen in this context of energy supply safety. They detail the today market and the perspectives, the energy sources for the hydrogen production (fossils, nuclear and renewable), the hydrogen transport, storage, distribution and conversion, the application domains, the associated risks. (A.L.B.)

  8. TECHNICAL COORDINATION

    CERN Multimedia

    Austin Ball

    2013-01-01

      Since the last report, much visible progress has been made, as the LS1 programme approaches the halfway point. From early October, technical and safety shift-crew have been present around the clock, allowing detectors to stay switched on overnight, ensuring that safety systems are operational and instructions for non-expert shift-crew are clear. LS1 progress Throughout the summer, whilst the solenoid vacuum tank and YB0 surfaces were accessible, an extensive installation programme took place to prepare for Tracker colder operation and the PLT installation, in 2014, the Phase 1 Pixel Tracker installation, in 2016–’17, and the HCAL Phase 1 upgrade completion, ending in LS2. This included pipework for N2 or dry air to flush the Tracker bulkhead region, many sensors to monitor temperature and dew point in the Tracker and its service channels, heating wires outside the Tracker cooling bundles, supports for the new vacuum-jacketed, concentric, CO2 Pixel cooling lines, the PLT cool...

  9. TECHNICAL COORDINATION

    CERN Multimedia

    A. Ball and W. Zeuner

    2012-01-01

      UXC + detectors As explained in detail in the November 2011 bulletin, the bellows unit at −18.5 m from the CMS interaction point was identified as a prime candidate for the regularly occurring pressure spikes which occasionally led to sustained severe background conditions in 2011, affecting dead time and data quality. Similar regions in LHC with vacuum instabilities were observed to be close to bellows, which radiography showed to have distorted RF-fingers — on removal, they proved to have been severely overheated. The plans for the Year-End Technical Stop were adapted to prioritise radiography of the bellows at 16 m to 18 m either end of CMS. Excellent work by the beam pipe, survey and heavy mechanical teams allowed the X-rays to be taken as planned on 20th December, showing that the bellow at −18.5m had an obvious non-conformity. The RF-fingers were found inside the end of the opposing flared pipe instead of outside. In addition, the overlap between fingers and...

  10. Mercury chemisorption by sulfur adsorbed in porous materials

    NARCIS (Netherlands)

    Steijns, M.; Peppelenbos, A.; Mars, P.

    1976-01-01

    The sorption of mercury vapor by adsorbed sulfur in the zeolites CaA (= 5A) and NaX (=13X) and two types of active carbon has been measured at a temperature of 50°C. With increasing degree of micropore filling by sulfur the fraction of sulfur accessible to mercury atoms decreased for CaA and NaX.

  11. Electrospun chitosan/baker's yeast nanofibre adsorbent: preparation ...

    Indian Academy of Sciences (India)

    poration, complexation, reverse osmosis and membrane pro- cesses [2–4]. ... activities and some human activities such as exploitation of uranium and ... bre adsorbent for U(VI) and Th(IV) removal from aqueous solutions. 2. Experimental ..... Adsorption capacity of uranium(VI) and thorium(IV) in binary systems. where. H.

  12. Substrate induced ordering of molecular adsorbates on Au(111)

    International Nuclear Information System (INIS)

    Schott, J.H.; White, H.S.; Arana, C.R.

    1992-01-01

    Using scanning tunneling microscopy in dimethylformate, [Ru(bpy) 2 (bpy-(CH 2 ) x -bpy) 2+ ] (x = 4 and 5) monolayers adsorbed on the unreconstructed and √3 x 22 reconstructed surfaces of Au(111) were imaged in this paper. The substrate had a highly ordered pattern on the reconstructed surface, but random spatial distribution on the unreconstructed surface. 17 refs., 3 figs

  13. Removal of nickel from wastewater using an agricultural adsorbent

    African Journals Online (AJOL)

    2009-11-26

    Nov 26, 2009 ... qmax is the theoretical maximum adsorption capacity of the adsorbent (mg/g). KL is the Langmuir affinity constant (ℓ/mg). Ce is the supernatant equilibrium concentration of the system (mg/ℓ) (Febrianto et al., 2009). The Freundlich isotherm model can also be expressed in the linearised logarithmic form (Eq.

  14. Magnetic-supported cucurbituril: A recyclable adsorbent for the ...

    Indian Academy of Sciences (India)

    Administrator

    removal of humic acid from simulated water. QIN YANG* ... The commonly used adsorbents are activated carbon. (Deng and Bai ... Q[n] is practically insoluble in all common organic solvents. ... Q[n] has other advantages such as its strong rigid structure .... and it does not result in the phase change of Fe3O4. In addition ...

  15. Interactions between adsorbed macromolecules : measurements on emulsions and liquid films

    NARCIS (Netherlands)

    Vliet, van T.

    1977-01-01

    The aim of this study was to gain more insight into the factors, determining the inter- and intramolecular interactions between adsorbed macromolecules. To that end several experimental and theoretical approaches were followed, using well-defined systems. It was shown that these

  16. Analytical phase diagrams for colloids and non-adsorbing polymer

    NARCIS (Netherlands)

    Fleer, G.J.; Tuinier, R.

    2008-01-01

    We review the free-volume theory (FVT) of Lekkerkerker et al. [Europhys. Lett. 20 (1992) 5591 for the phase behavior of colloids in the presence of non-adsorbing polymer and we extend this theory in several aspects: (i) We take the solvent into account as a separate component and show that the

  17. Application of adsorbent as a novel technique during ...

    African Journals Online (AJOL)

    STORAGESEVER

    2008-09-17

    Sep 17, 2008 ... hydrophilic compound (carbon), thermally activated at temperatures of 300, 500, 700 and ... carbon in microbial degradation of anthracene, elicits an enhanced disappearance rate of the ... persistence, toxicity and their tendency to bioaccumulate ... paper therefore, investigates the use of adsorbent (acti-.

  18. Theoretical study of hydrogen storage in metal hydrides.

    Science.gov (United States)

    Oliveira, Alyson C M; Pavão, A C

    2018-05-04

    Adsorption, absorption and desorption energies and other properties of hydrogen storage in palladium and in the metal hydrides AlH 3 , MgH 2 , Mg(BH 4 ) 2 , Mg(BH 4 )(NH 2 ) and LiNH 2 were analyzed. The DFT calculations on cluster models show that, at a low concentration, the hydrogen atom remains adsorbed in a stable state near the palladium surface. By increasing the hydrogen concentration, the tetrahedral and the octahedral sites are sequentially occupied. In the α phase the tetrahedral site releases hydrogen more easily than at the octahedral sites, but the opposite occurs in the β phase. Among the hydrides, Mg(BH 4 ) 2 shows the highest values for both absorption and desorption energies. The absorption energy of LiNH 2 is higher than that of the palladium, but its desorption energy is too high, a recurrent problem of the materials that have been considered for hydrogen storage. The release of hydrogen, however, can be favored by using transition metals in the material structure, as demonstrated here by doping MgH 2 with 3d and 4d-transition metals to reduce the hydrogen atomic charge and the desorption energy.

  19. Hydrogen in metals

    CSIR Research Space (South Africa)

    Carter, TJ

    2001-04-01

    Full Text Available .J. Cartera,*, L.A. Cornishb aAdvanced Engineering & Testing Services, MATTEK, CSIR, Private Bag X28, Auckland Park 2006, South Africa bSchool of Process and Materials Engineering, University of the Witwatersrand, Private Bag 3, P.O. WITS 2050, South Africa... are contrasted, and an unusual case study of hydrogen embrittlement of an alloy steel is presented. 7 2001 Published by Elsevier Science Ltd. Keywords: Hydrogen; Hydrogen-assisted cracking; Hydrogen damage; Hydrogen embrittlement 1. Introduction Hydrogen suC128...

  20. Natural material adsorbed onto a polymer to enhance immune function

    Directory of Open Access Journals (Sweden)

    Reinaque AP

    2012-08-01

    Full Text Available Ana Paula Barcelos Reinaque,1 Eduardo Luzía França,2 Edson Fredulin Scherer,3 Mayra Aparecida Côrtes,1 Francisco José Dutra Souto,4 Adenilda Cristina Honorio-França51Post Graduate Program in Material Science, 2Institute of Biological and Health Science, Federal University of Mato Grosso, Barra do Garças, 3Post Graduate Program in Material Science, Institute of Biological and Health Science, Federal University of Mato Grosso, Pontal do Araguaia, 4Faculty of Medical Sciences, Federal University of Mato Grosso, Cuiabá, 5Institute of Biological and Health Science, Federal University of Mato Grosso, Pontal do Araguaia, MT, BrazilBackground: In this study, we produced poly(ethylene glycol (PEG microspheres of different sizes and adsorbing a medicinal plant mixture, and verified their effect in vitro on the viability, superoxide production, and bactericidal activity of phagocytes in the blood.Methods: The medicinal plant mixture was adsorbed onto PEG microspheres and its effects were evaluated by flow cytometry and fluorescence microscopy.Results: Adsorption of the herbal mixture onto the PEG microspheres was achieved and the particles were internalized by phagocytes. PEG microspheres bearing the adsorbed herbal mixture stimulated superoxide release, and activated scavenging and microbicidal activity in phagocytes. No differences in functional activity were observed when the phagocytes were not incubated with PEG microspheres bearing the adsorbed herbal mixture.Conclusion: This system may be useful for the delivery of a variety of medicinal plants and can confer additional protection against infection. The data reported here suggest that a polymer adsorbed with a natural product is a treatment alternative for enhancing immune function.Keywords: natural product, polymer, adsorption, immune function, phagocytes

  1. Technical innovation and management

    Energy Technology Data Exchange (ETDEWEB)

    Yoon, Yang Cheol

    1982-08-15

    This book gives explanations of the conception of technical innovation, development plan in Korea, connection between technology and a growth factor in national income, problem of technical innovation in developing country, analysis on cooperation between a developed country and a developing country, evaluation and strategy of technical development in Korea, technical innovation of industry, management of technical industry, analysis of special condition in Korea.

  2. Technical innovation and management

    International Nuclear Information System (INIS)

    Yoon, Yang Cheol

    1982-08-01

    This book gives explanations of the conception of technical innovation, development plan in Korea, connection between technology and a growth factor in national income, problem of technical innovation in developing country, analysis on cooperation between a developed country and a developing country, evaluation and strategy of technical development in Korea, technical innovation of industry, management of technical industry, analysis of special condition in Korea.

  3. Hydrogen spillover on DV (555-777) graphene – vanadium cluster system: First principles study

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, E. Mathan, E-mail: ranjit.t@res.srmuniv.ac.in, E-mail: mathanranjitha@gmail.com; Thapa, Ranjit, E-mail: ranjit.t@res.srmuniv.ac.in, E-mail: mathanranjitha@gmail.com [SRM Research Institute, SRM University, Kattankulathur, Tamil Nadu - 603203 (India); P, Sabarikirishwaran [Department of Physics and Nanotechnology, SRM University, Kattankulathur, Tamil Nadu - 603203 (India)

    2015-06-24

    Using dispersion corrected density functional theory (DFT+D), the interaction of Vanadium adatom and cluster with divacancy (555-777) defective graphene sheet has been studied elaborately. We explore the prospect of hydrogen storage on V{sub 4} cluster adsorbed divacancy graphene system. It has been observed that V{sub 4} cluster (acting as a catalyst) can dissociate the H{sub 2} molecule into H atoms with very low barrier energy. We introduce the spillover of the atomic hydrogen throughout the surface via external mediator gallane (GaH{sub 3}) to form a hydrogenated system.

  4. Hydrogenation of hexene over platinum on alumina vs. platinum in a Na-Y zeolite

    International Nuclear Information System (INIS)

    Miner, R.S. Jr.; Ione, K.G.; Namba, S.; Turkevich, J.

    1978-01-01

    In order to study the efficacy of zeolites as supports, several platinum H--Y zeolites were prepared by ion exchanging an H--Y zeolite with Pt(NH 3 ) 4 Cl 2 and reducing these products with hydrazine hydrate (A, B, C). Another preparation was made by adsorbing 32-A platinum sol on the zeolite crystallites (D). These catalysts were studied for hydrogenation and isomerization of hexene-1, ethylene hydrogenation, hydrogen chemisorption, and poison titration. They were compared with monodisperse Pt (32 A diameter) on alumina. A marked difference was found between the behavior of hexene-1 with the platinum-in-zeolite and with the platinum-on-alumina

  5. Technical-economic study of the development of a hydrogen-based energy system in Venezuela; Estudio tecnico-economico del desarrollo en Venezuela de un sistema energetico basado en el hidrogeno

    Energy Technology Data Exchange (ETDEWEB)

    Posso, F. [ULA-Tachira. San Cristobal (Venezuela)] email: fausto@ula.ve; Contreras, A. [ETSII-UNED (Venezuela)

    2009-09-15

    The feasibility of the development in Venezuela of a hydroelectric/hydrogen energy system (HHES) was studied. The application of this system is intended for rural sectors in the country with no available permanent and safe energy services. The study was conducted by developing and later simulating a mathematical model for each of the components of the energy system: transformation, storage, transport, distribution and final use. Structurally, the models are composed of an energy sub-model and a cost sub-model. The HHES model as a whole is obtained from the connection of the models and the components. The simulation is performed for operating conditions and parameter values that are most favorable for the proposed use, with the same temporal period in all cases. The results indicate that the annual production of H{sub 2} must increase in order to satisfy the growing energy needs of the rural study population. The total annual costs of the HHES decreased during the study period, primarily due to a decrease in the costs of the final use component, which indicates the behavior of total costs. A comparison of the results obtained with those from the literature demonstrate interest in the proposed system given the ideal economic and environmental conditions provided to the zone selected, primarily due to the availability of inexpensive hydroelectric energy in the country. The current feasibility of the development of the HHES is shown, as compared to the option of supplying electric energy to rural population centers via traditional electric installations. [Spanish] Se estudia la viabilidad del desarrollo en Venezuela del Sistema Energetico Hidroelectricidad/Hidrogeno, SEHH, con vista a su aplicacion en sectores rurales del pais que no disponen de servicios permanentes y seguros de energia. El estudio se realiza mediante la elaboracion y posterior simulacion de un modelo matematico para cada uno de los componentes del sistema energetico: transformacion, almacenamiento

  6. Using the solar energy by technical photosynthesis

    International Nuclear Information System (INIS)

    Radebold, R.

    1975-01-01

    A system is decribed which makes it possible to copy some of the basic features of photosynthesis with technical means which are available to-day. Hydrazine and hydrogen peroxide are used as energy carrier, whereby hydrazine acts a propellant and hydrogen peroxide as oxidator. The synthesis of the two media is based on nitrogen and water which can, in principle, be taken from the air; nitrogen and water are also the products of the reactions. Liquid alcali metals are the donators of electrons for the synthesis which occurs, as in nature, by the intermediate action of electric energy. (orig.) [de

  7. Modeling of the thermal effects of hydrogen adsorption on activated carbon

    International Nuclear Information System (INIS)

    Richard, M.-A.; Chahine, R.

    2006-01-01

    'Full text:' Heat management is one of the most critical issues for the design of efficient adsorption-based storage of hydrogen. We present simulations of mass and energy balance for hydrogen and nitrogen adsorption on activated carbon over wide temperature and pressure ranges. First, the Dubinin-Astakhov (DA) model is adapted to model excess hydrogen and nitrogen adsorption isotherms at high pressures and supercritical temperatures assuming a constant microporous adsorption volume. The five parameter modified D-A adsorption model is shown to fit the experimental data over the temperature range (35 K-293 K) for hydrogen and (93 K-298 K) for nitrogen and pressure range (0-6 MPa) within the experimental uncertainties of the measurement system. We derive the thermodynamic properties of the adsorbed phase from this analytical expression of the measured data. The mass and energy rate balance equations in a microporous adsorbent/adsorbate system are then presented and validated with nitrogen desorption experiments. Finally, simulations of adiabatic and isothermal filling of adsorption-based hydrogen storage are presented and discussed. (author)

  8. Fundamental hydrogen interactions with beryllium : a magnetic fusion perspective.

    Energy Technology Data Exchange (ETDEWEB)

    Wampler, William R. (Sandia National Laboratories, Albuquerque, NM); Felter, Thomas E.; Whaley, Josh A.; Kolasinski, Robert D.; Bartelt, Norman Charles

    2012-03-01

    Increasingly, basic models such as density functional theory and molecular dynamics are being used to simulate different aspects of hydrogen recycling from plasma facing materials. These models provide valuable insight into hydrogen diffusion, trapping, and recombination from surfaces, but their validation relies on knowledge of the detailed behavior of hydrogen at an atomic scale. Despite being the first wall material for ITER, basic single crystal beryllium surfaces have been studied only sparsely from an experimental standpoint. In prior cases researchers used electron spectroscopy to examine surface reconstruction or adsorption kinetics during exposure to a hydrogen atmosphere. While valuable, these approaches lack the ability to directly detect the positioning of hydrogen on the surface. Ion beam techniques, such as low energy ion scattering (LEIS) and direct recoil spectroscopy (DRS), are two of the only experimental approaches capable of providing this information. In this study, we applied both LEIS and DRS to examine how hydrogen binds to the Be(0001) surface. Our measurements were performed using an angle-resolved ion energy spectrometer (ARIES) to probe the surface with low energy ions (500 eV - 3 keV He{sup +} and Ne{sup +}). We were able to obtain a 'scattering maps' of the crystal surface, providing insight on how low energy ions are focused along open surface channels. Once we completed a characterization of the clean surface, we dosed the sample with atomic hydrogen using a heated tungsten capillary. A distinct signal associated with adsorbed hydrogen emerged that was consistent with hydrogen residing between atom rows. To aid in the interpretation of the experimental results, we developed a computational model to simulate ion scattering at grazing incidence. For this purpose, we incorporated a simplified surface model into the Kalypso molecular dynamics code. This approach allowed us to understand how the incident ions interacted with the

  9. Fuel Cell and Hydrogen Technologies Program | Hydrogen and Fuel Cells |

    Science.gov (United States)

    NREL Fuel Cell and Hydrogen Technologies Program Fuel Cell and Hydrogen Technologies Program Through its Fuel Cell and Hydrogen Technologies Program, NREL researches, develops, analyzes, and validates fuel cell and hydrogen production, delivery, and storage technologies for transportation

  10. Dynamics of hydrogen in hydrogenated amorphous silicon

    Indian Academy of Sciences (India)

    is mobile and can easily move through the material). Hydrogen diffuses ... The determination of the relationship of light-enhanced hydrogen motion to ... term is negligible, and using the thermodynamic relation given below f(c) = kBT .... device-applications problematic but the normal state can be recovered by a thermal an-.

  11. Potensi bambu swat (gigantochloa verticillata sebagai material karbon aktif untuk adsorbed natural gas (ANG

    Directory of Open Access Journals (Sweden)

    Dewa Ngakan Ketut Putra Negara

    2017-03-01

    Full Text Available Abstrak: Bambu merupakan material biomassa yang banyak diteliti, diproduksi sebagai karbon aktif dan diaplikasikan di berbagaibidang kehidupan. Namun sangat sedikit bahkan hampir tidak ditemukan referensi yang membahas kegunaan karbonaktif dari bambusebagai adsorbent untuk Adsorbed Natural Gas (ANG. Penelitian ini difokuskan untukmengkarakterisasai dan menevaluasi potensi bambu swat (Gigantochloa verticillata sebagai material dasar karbon aktifuntuk aplikasi ANG. Pengujian yang dilakukan meliputi uji proximate, uji ultimate, uji komposisi kimia dan pengamatanstruktur mikro. Hasil penelitian menunjukkan bahwa bambuswat memiliki kandungan lignin 22,9920%, selulosa44,2247%, volatile 88’32%, carbon 43,42%,ash 1,83%, silica (1,8664% dan nitrogen 1,7065%. Bambu swat memilikiikatan pembuluh yang terdiri atas satu ikatan pembuluh (xilem dan floem dan dua ikatan serat yang terletak di sebelahdalam dan luar dari ikatan pembuluh.Secara umum dapat dikatakan bahwa bamboo jenis ini memiliki kandungansellulosa, volatile dan karbon yang cukup tinggi serta ash, silica, hydrogen dan nitrogen yang rendah sehinggabambuswat sangat berpotensi digunakan sebagai material sumber karbon aktif.Kata kunci: Karbon aktif, bambu swat, ANG, lignin, sellulosa, analisa ultimate dan proximates Abstract: Bamboo is a biomass material widely researched, produced as activated carbon and applied in various life fields.However, very little or almost no references were found with regard to utilization of bamboo activated carbon asadsorbent for Adsorbed Natural Gas (ANG. This study is concerned to characterize and evaluate potency of bambooswat (Gigantochloa verticillata as aprecursor of activated carbon for ANG application. Examinations conducted wereproximate, ultimate, chemical composisition tests and microstructure observation. The results showed that bambooswathave a lignin content 22.9920%, cellulose 44.2247%, volatile 88.32%, carbon 43.42%, ash 1.83%, silica 1.8664% andnitrogen

  12. Handbook of hydrogen energy

    CERN Document Server

    Sherif, SA; Stefanakos, EK; Steinfeld, Aldo

    2014-01-01

    ""This book provides an excellent overview of the hydrogen economy and a thorough and comprehensive presentation of hydrogen production and storage methods.""-Scott E. Grasman, Rochester Institute of Technology, New York, USA

  13. Hydrogen production by Cyanobacteria

    Directory of Open Access Journals (Sweden)

    Chaudhuri Surabhi

    2005-12-01

    Full Text Available Abstract The limited fossil fuel prompts the prospecting of various unconventional energy sources to take over the traditional fossil fuel energy source. In this respect the use of hydrogen gas is an attractive alternate source. Attributed by its numerous advantages including those of environmentally clean, efficiency and renew ability, hydrogen gas is considered to be one of the most desired alternate. Cyanobacteria are highly promising microorganism for hydrogen production. In comparison to the traditional ways of hydrogen production (chemical, photoelectrical, Cyanobacterial hydrogen production is commercially viable. This review highlights the basic biology of cynobacterial hydrogen production, strains involved, large-scale hydrogen production and its future prospects. While integrating the existing knowledge and technology, much future improvement and progress is to be done before hydrogen is accepted as a commercial primary energy source.

  14. Center for Hydrogen Storage.

    Science.gov (United States)

    2013-06-01

    The main goals of this project were to (1) Establish a Center for Hydrogen Storage Research at Delaware State University for the preparation and characterization of selected complex metal hydrides and the determination their suitability for hydrogen ...

  15. Hydrogen release at metal-oxide interfaces: A first principle study of hydrogenated Al/SiO{sub 2} interfaces

    Energy Technology Data Exchange (ETDEWEB)

    Huang, Jianqiu, E-mail: jianqiu@vt.edu [Department of Mechanical Engineering, Virginia Tech, Goodwin Hall, 635 Prices Fork Road - MC 0238, Blacksburg, VA 24061 (United States); Tea, Eric; Li, Guanchen [Department of Mechanical Engineering, Virginia Tech, Goodwin Hall, 635 Prices Fork Road - MC 0238, Blacksburg, VA 24061 (United States); Hin, Celine [Department of Mechanical Engineering, Virginia Tech, Goodwin Hall, 635 Prices Fork Road - MC 0238, Blacksburg, VA 24061 (United States); Department of Material Science and Engineering, Virginia Tech, Goodwin Hall, 635 Prices Fork Road-MC 0238, Blacksburg, VA 24061 (United States)

    2017-06-01

    Highlights: • Hydrogen release process at the Al/SiO{sub 2} metal-oxide interface has been investigated. • A mathematical model that estimates the hydrogen release potential has been proposed. • Al atoms, Al−O bonds, and Si−Al bonds are the major hydrogen traps at the Al/SiO{sub 2} interface. • Hydrogen atoms are primarily release from Al−H and O−H bonds at the Al/SiO{sub 2} metal-oxide interface. - Abstract: The Anode Hydrogen Release (AHR) mechanism at interfaces is responsible for the generation of defects, that traps charge carriers and can induce dielectric breakdown in Metal-Oxide-Semiconductor Field Effect Transistors. The AHR has been extensively studied at Si/SiO{sub 2} interfaces but its characteristics at metal-silica interfaces remain unclear. In this study, we performed Density Functional Theory (DFT) calculations to study the hydrogen release mechanism at the typical Al/SiO{sub 2} metal-oxide interface. We found that interstitial hydrogen atoms can break interfacial Al−Si bonds, passivating a Si sp{sup 3} orbital. Interstitial hydrogen atoms can also break interfacial Al−O bonds, or be adsorbed at the interface on aluminum, forming stable Al−H−Al bridges. We showed that hydrogenated O−H, Si−H and Al−H bonds at the Al/SiO{sub 2} interfaces are polarized. The resulting bond dipole weakens the O−H and Si−H bonds, but strengthens the Al−H bond under the application of a positive bias at the metal gate. Our calculations indicate that Al−H bonds and O−H bonds are more important than Si−H bonds for the hydrogen release process.

  16. Hydrogen Induced Cracking of Drip Shield

    Energy Technology Data Exchange (ETDEWEB)

    G. De

    2003-02-24

    One potential failure mechanism for titanium and its alloys under repository conditions is via the absorption of atomic hydrogen in the metal crystal lattice. The resulting decreased ductility and fracture toughness may lead to brittle mechanical fracture called hydrogen-induced cracking (HIC) or hydrogen embrittlement. For the current design of the engineered barrier without backfill, HIC may be a problem since the titanium drip shield can be galvanically coupled to rock bolts (or wire mesh), which may fall onto the drip shield, thereby creating conditions for hydrogen production by electrochemical reaction. The purpose of this scientific analysis and modeling activity is to evaluate whether the drip shield will fail by HIC or not under repository conditions within 10,000 years of emplacement. This Analysis and Model Report (AMR) addresses features, events, and processes related to hydrogen induced cracking of the drip shield. REV 00 of this AMR served as a feed to ''Waste Package Degradation Process Model Report'' and was developed in accordance with the activity section ''Hydrogen Induced Cracking of Drip Shield'' of the development plan entitled ''Analysis and Model Reports to Support Waste Package PMR'' (CRWMS M&O 1999a). This AMR, prepared according to ''Technical Work Plan for: Waste Package Materials Data Analyses and Modeling'' (BSC 2002), is to feed the License Application.

  17. Hydrogen gas getters: Susceptibility to poisoning

    International Nuclear Information System (INIS)

    Mroz, E.J.; Dye, R.C.; Duke, J.R.; Weinrach, J.

    1998-01-01

    About 40% (∼9,000) of the ∼23,000 transuranic (TRU) waste drums at Los Alamos National Laboratory (LANL) are presently unshippable because conservative calculations suggest that the hydrogen concentration may exceed the lower explosive limit for hydrogen. This situation extends across nearly all DOE sites holding and generating TRU waste. The incorporation of a hydrogen getter such as DEB into the waste drums (or the TRUPACT II shipping containers) could substantially mitigate the explosion risk. The result would be to increase the number of drums that qualify for transportation to the Waste Isolation Pilot Plant (WIPP) without having to resort to expensive re-packaging or waste treatment technologies. However, before this approach can be implemented, key technical questions must be answered. Foremost among these is the question of whether the presence of other chemical vapors and gases in the drum might poison the catalytic reaction between hydrogen and DEB. This is the final report of a one-year, Laboratory Directed Research and Development (LDRD) project at the Los Alamos National Laboratory (LANL). The objective of this project was to obtain fundamental information on the chemical mechanism of the catalytic reaction of hydrogen with one commonly used hydrogen getter, DEB. Experiments with these materials showed that the method of exposure affects the nature of the reaction products. The results of this work contributed to the development of a mechanistic model of the reaction

  18. H/CNG pathway to hydrogen

    International Nuclear Information System (INIS)

    Bugyra, W.J.; Martin, D.R.

    2004-01-01

    'Full text:' The addition of hydrogen to natural gas to produce a 'premium' fuel offers an ideal bridge to the hydrogen and fuel cell era. This pathway provides many of the expected benefits of hydrogen and fuel cells, reduces cost and risk, and facilitates the transition to hydrogen incrementally through existing infrastructure, technologies and channels. The H/CNG pathway is evaluated qualitatively and quantitatively in the context of: barriers to introducing hydrogen infrastructure and how they can be addressed; potential benefits (emissions, energy security) and drawbacks (range, technical compatibility) of H/CNG blended fuels; economics; and, comparative analysis to the use of ethanol in gasoline. Leveraging the NGV industry eases the transition to fuel cells by taking advantage of existing infrastructure, technologies, skills, codes and standards, and provides for incremental change that may be more acceptable to consumers, regulators and incumbent technology providers. The greatest benefits can be achieved through a two-track pathway. One would utilize small amounts of hydrogen in existing NGVs and installed power systems - much as ethanol is added to gasoline. The second introduce products designed specifically to operate on higher levels of H/CNG, like buses, in concentrations where the greatest emission benefits can be achieved. (author)

  19. The effect of amorphous silicon surface hydrogenation on morphology, wettability and its implication on the adsorption of proteins

    Energy Technology Data Exchange (ETDEWEB)

    Filali, Larbi, E-mail: larbifilali5@gmail.com [Laboratoire de Physique des Couches Minces et Matériaux pour l' Electronique, Université d' Oran 1, Ahmed Ben Bella, BP 1524, El M' naouar 31100 Oran (Algeria); Brahmi, Yamina; Sib, Jamal Dine [Laboratoire de Physique des Couches Minces et Matériaux pour l' Electronique, Université d' Oran 1, Ahmed Ben Bella, BP 1524, El M' naouar 31100 Oran (Algeria); Bouhekka, Ahmed [Laboratoire de Physique des Couches Minces et Matériaux pour l' Electronique, Université d' Oran 1, Ahmed Ben Bella, BP 1524, El M' naouar 31100 Oran (Algeria); Département de Physique, Université Hassiba Ben Bouali, 02000 Chlef (Algeria); Benlakehal, Djamel; Bouizem, Yahya; Kebab, Aissa; Chahed, Larbi [Laboratoire de Physique des Couches Minces et Matériaux pour l' Electronique, Université d' Oran 1, Ahmed Ben Bella, BP 1524, El M' naouar 31100 Oran (Algeria)

    2016-10-30

    Highlights: • Hydrogenation of the surfaces had the effect of reducing the roughness by way of shadow etching. • Roughness was the driving factor affecting the wettability of the hydrogenated surfaces. • Bovine Serum Albumin proteins favored the surfaces with highest hydrogen content. • Surface modification induced secondary structure change of adsorbed proteins. - Abstract: We study the effect of amorphous silicon (a-Si) surface hydrogenation on Bovine Serum Albumin (BSA) adsorption. A set of (a-Si) films was prepared by radio frequency magnetron sputtering (RFMS) and after deposition; they were treated in molecular hydrogen ambient at different pressures (1–3 Pa). Fourier transform infrared attenuated total reflection (FTIR-ATR) spectroscopy and spectroscopic ellipsometry (SE) were used to study the hydrogenation effect and BSA adsorption. Atomic force microscopy (AFM) was used to evaluate morphological changes caused by hydrogenation. The wettability of the films was measured using contact angle measurement, and in the case of the hydrogenated surfaces, it was found to be driven by surface roughness. FTIR-ATR spectroscopy and SE measurements show that proteins had the strongest affinity toward the surfaces with the highest hydrogen content and their secondary structure was affected by a significant decrease of the α-helix component (-27%) compared with the proteins adsorbed on the un-treated surface, which had a predominantly α-helix (45%) structure. The adsorbed protein layer was found to be densely packed with a large thickness (30.9 nm) on the hydrogen-rich surfaces. The most important result is that the surface hydrogen content was the dominant factor, compared to wettability and morphology, for protein adsorption.

  20. Nuclear electrolytic hydrogen

    International Nuclear Information System (INIS)

    Barnstaple, A.G.; Petrella, A.J.

    1982-05-01

    An extensive study of hydrogen supply has recently been carried out by Ontario Hydro which indicates that electrolytic hydrogen produced from nuclear electricity could offer the lowest cost option for any future large scale hydrogen supply in the Province of Ontario, Canada. This paper provides a synopsis of the Ontario Hydro study, a brief overview of the economic factors supporting the study conclusion and discussion of a number of issues concerning the supply of electrolytic hydrogen by electric power utilities