Thermodynamic and Kinetic Considerations Regarding the Prospects for a Dual-Purpose Hydrogen Extraction and Separation Membrane

Extraction of hydrogen from hydrocarbons is a logical intermediate-term solution for the escalating worldwide demand for hydrogen. This work explores the possibility of using a single membrane to accomplish both the catalytic dehydrogenation and physical separation of hydrogen gas as a possible way to improve the efficiency of hydrogen production from hydrocarbon sources. The present analysis shows that regions of pressure/temperature space exist for which the overall process is thermodynamically spontaneous (ΔG < 0). Each step in the process is based on known physics. The rate of hydrogen production is likely to be controlled by the barrier to hydrogen abstraction, with the density of H-binding sites also playing a role. A critical materials issue will be the strength of the oxide/metal interface.

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Pt@Cu/C Core-Shell Catalysts for Hydrogen Production Through Catalytic Dehydrogenation of Decalin

Korean Journal of Materials Research ◽

10.3740/mrsk.2016.26.1.17 ◽

2016 ◽

Vol 26 (1) ◽

pp. 17-21

Author(s):

Ji Yeon Kang ◽

Gihoon Lee ◽

Yeojin Jeong ◽

Hyon Bin Na ◽

Ji Chul Jung

Keyword(s):

Hydrogen Production ◽

Core Shell ◽

Catalytic Dehydrogenation

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Iridium Complex Catalyzed Hydrogen Production from Glucose and Various Monosaccharides

Catalysts ◽

10.3390/catal11080891 ◽

2021 ◽

Vol 11 (8) ◽

pp. 891

Author(s):

Ken-ichi Fujita ◽

Takayoshi Inoue ◽

Toshiki Tanaka ◽

Jaeyoung Jeong ◽

Shohichi Furukawa ◽

...

Keyword(s):

Hydrogen Production ◽

Catalytic System ◽

Catalytic Reaction ◽

Hydrogen Gas ◽

Water Soluble ◽

Starting Material ◽

Iridium Complex ◽

Production Of Hydrogen ◽

Bipyridine Ligand

A new catalytic system has been developed for hydrogen production from various monosaccharides, mainly glucose, as a starting material under reflux conditions in water in the presence of a water-soluble dicationic iridium complex bearing a functional bipyridine ligand. For example, the reaction of D-glucose in water under reflux for 20 h in the presence of [Cp*Ir(6,6′-dihydroxy-2,2′-bipyridine)(H2O)][OTf]2 (1.0 mol %) (Cp*: pentamethylcyclopentadienyl, OTf: trifluoromethanesulfonate) resulted in the production of hydrogen gas in 95% yield. In the present catalytic reaction, it was experimentally suggested that dehydrogenation of the alcoholic moiety at 1-position of glucose proceeded.

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Carbons Formed in Methane Thermal and Thermocatalytic Decomposition Processes: Properties and Applications

C – Journal of Carbon Research ◽

10.3390/c7030050 ◽

2021 ◽

Vol 7 (3) ◽

pp. 50

Author(s):

Emmi Välimäki ◽

Lasse Yli-Varo ◽

Henrik Romar ◽

Ulla Lassi

Keyword(s):

Thermal Decomposition ◽

Hydrogen Production ◽

Energy Systems ◽

Hydrogen Gas ◽

Solid Carbon ◽

Hydrogen Economy ◽

Decomposition Processes ◽

Different Types ◽

Decomposition Of Methane ◽

Thermocatalytic Decomposition

The hydrogen economy will play a key role in future energy systems. Several thermal and catalytic methods for hydrogen production have been presented. In this review, methane thermocatalytic and thermal decomposition into hydrogen gas and solid carbon are considered. These processes, known as the thermal decomposition of methane (TDM) and thermocatalytic decomposition (TCD) of methane, respectively, appear to have the greatest potential for hydrogen production. In particular, the focus is on the different types and properties of carbons formed during the decomposition processes. The applications for carbons are also investigated.

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Analysis on Characteristic of Hydrogen Gas Dispersion and Evaluation Method of Blast Overpressure in VHTR Hydrogen Production System

Transactions of the Atomic Energy Society of Japan ◽

10.3327/taesj2002.5.316 ◽

2006 ◽

Vol 5 (4) ◽

pp. 316-324 ◽

Cited By ~ 7

Author(s):

Tomoyuki MURAKAMI ◽

Atsuhiko TERADA ◽

Tetsuo NISHIHARA ◽

Yoshiyuki INAGAKI ◽

Kazuhiko KUNITOMI

Keyword(s):

Hydrogen Production ◽

Production System ◽

Evaluation Method ◽

Hydrogen Gas ◽

Gas Dispersion ◽

Blast Overpressure

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Reactive Molecular Dynamics Simulations, Data Analytics and Visualization

MRS Proceedings ◽

10.1557/opl.2015.201 ◽

2015 ◽

Vol 1756 ◽

Author(s):

Priya Vashishta ◽

Rajiv K. Kalia ◽

Aiichiro Nakano ◽

Ying Li ◽

Ken-ichi Nomura ◽

...

Keyword(s):

Molecular Dynamics ◽

Hydrogen Production ◽

Density Functional ◽

Silica Surface ◽

Hydrogen Gas ◽

Divide And Conquer ◽

List Type ◽

Reactive Molecular Dynamics ◽

Production Of Hydrogen ◽

Blue Gene

ABSTRACTMultimillion-atom reactive molecular dynamics (RMD) and large quantum molecular dynamics (QMD) simulations are used to investigate structural and dynamical correlations under highly nonequilibrium conditions and reactive processes in nanostructured materials under extreme conditions. This paper discusses four simulations:1.RMD simulations of heated aluminum nanoparticles have been performed to study the fast oxidation reaction processes of the core (aluminum)-shell (alumina) nanoparticles and small complexes.2.Cavitation bubbles readily occur in fluids subjected to rapid changes in pressure. We have used billion-atom RMD simulations on a 163,840-processor Blue Gene/P supercomputer to investigate chemical and mechanical damages caused by shock-induced collapse of nanobubbles in water near silica surface. Collapse of an empty nanobubble generates high-speed nanojet, resulting in the formation of a pit on the surface. The gas-filled bubbles undergo partial collapse and consequently the damage on the silica surface is mitigated.3.Our QMD simulation reveals rapid hydrogen production from water by an Al superatom. We have found a low activation-barrier mechanism, in which a pair of Lewis acid and base sites on the Aln surface preferentially catalyzes hydrogen production.4.We have introduced an extension of the divide-and-conquer (DC) algorithmic paradigm called divide-conquer-recombine (DCR) to perform large QMD simulations on massively parallel supercomputers, in which interatomic forces are computed quantum mechanically in the framework of density functional theory (DFT). A benchmark test on an IBM Blue Gene/Q computer exhibits an isogranular parallel efficiency of 0.984 on 786,432 cores for a 50.3 million-atom SiC system. As a test of production runs, LDC-DFT-based QMD simulation involving 16,661 atoms was performed on the Blue Gene/Q to study on-demand production of hydrogen gas from water using LiAl alloy particles.

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Photoelectrochemical Water Splitting Reaction System Based on Metal-Organic Halide Perovskites

Materials ◽

10.3390/ma13010210 ◽

2020 ◽

Vol 13 (1) ◽

pp. 210 ◽

Cited By ~ 5

Author(s):

Dohun Kim ◽

Dong-Kyu Lee ◽

Seong Min Kim ◽

Woosung Park ◽

Uk Sim

Keyword(s):

Hydrogen Production ◽

Water Splitting ◽

Fossil Fuels ◽

Reaction System ◽

Hydrogen Gas ◽

Production Environment ◽

Organic Halide ◽

Highly Active ◽

Production Of Hydrogen ◽

Metal Organic

In the development of hydrogen-based technology, a key challenge is the sustainable production of hydrogen in terms of energy consumption and environmental aspects. However, existing methods mainly rely on fossil fuels due to their cost efficiency, and as such, it is difficult to be completely independent of carbon-based technology. Electrochemical hydrogen production is essential, since it has shown the successful generation of hydrogen gas of high purity. Similarly, the photoelectrochemical (PEC) method is also appealing, as this method exhibits highly active and stable water splitting with the help of solar energy. In this article, we review recent developments in PEC water splitting, particularly those using metal-organic halide perovskite materials. We discuss the exceptional optical and electrical characteristics which often dictate PEC performance. We further extend our discussion to the material limit of perovskite under a hydrogen production environment, i.e., that PEC reactions often degrade the contact between the electrode and the electrolyte. Finally, we introduce recent improvements in the stability of a perovskite-based PEC device.

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Activated carbon aerogel-supported platinum catalyst for hydrogen production through catalytic dehydrogenation of decalin

10.5176/2251-189x_sees15.56 ◽

2015 ◽

Author(s):

Gihoon Lee ◽

Yeojin Jeong ◽

Ji Chul Jung

Keyword(s):

Activated Carbon ◽

Hydrogen Production ◽

Platinum Catalyst ◽

Carbon Aerogel ◽

Catalytic Dehydrogenation ◽

Supported Platinum ◽

Supported Platinum Catalyst

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CO2as a hydrogen vector – transition metal diamine catalysts for selective HCOOH dehydrogenation

Dalton Transactions ◽

10.1039/c6dt04638j ◽

2017 ◽

Vol 46 (5) ◽

pp. 1670-1676 ◽

Cited By ~ 19

Author(s):

Cornel Fink ◽

Gábor Laurenczy

Keyword(s):

Aqueous Solution ◽

Hydrogen Production ◽

Transition Metal ◽

Formic Acid ◽

Catalytic Dehydrogenation ◽

Mild Conditions ◽

Adjustable Rate

The homogeneous catalytic dehydrogenation of formic acid in aqueous solution provides an efficientin situmethod for hydrogen production, under mild conditions, and at an adjustable rate.

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Dynamic Hydrogen Production from Methanol/Water Photo-Splitting Using Core@Shell-Structured CuS@TiO2Catalyst Wrapped by High Concentrated TiO2Particles

International Journal of Photoenergy ◽

10.1155/2013/452542 ◽

2013 ◽

Vol 2013 ◽

pp. 1-10 ◽

Cited By ~ 12

Author(s):

Younghwan Im ◽

Sora Kang ◽

Kang Min Kim ◽

Taeil Ju ◽

Gi Bo Han ◽

...

Keyword(s):

Hydrogen Production ◽

Reduction Potential ◽

Hydrogen Gas ◽

Electronic Transitions ◽

Core Shell ◽

High Concentration ◽

Visible Absorption ◽

Long Wavelength ◽

The Core ◽

Uv Visible

This study focused on the dynamic hydrogen production ability of a core@shell-structured CuS@TiO2photocatalyst coated with a high concentration of TiO2particles. The rectangular-shaped CuS particles, 100 nm in length and 60 nm in width, were surrounded by a high concentration of anatase TiO2particles (>4~5 mol). The synthesized core@shell-structured CuS@TiO2particles absorbed a long wavelength (a short band gap) above 700 nm compared to that pure TiO2, which at approximately 300 nm, leading to easier electronic transitions, even at low energy. Hydrogen evolution from methanol/water photo-splitting over the core@shell-structured CuS@TiO2photocatalyst increased approximately 10-fold compared to that over pure CuS. In particular, 1.9 mmol of hydrogen gas was produced after 10 hours when 0.5 g of 1CuS@4TiO2was used at pH = 7. This level of production was increased to more than 4-fold at higher pH. Cyclic voltammetry and UV-visible absorption spectroscopy confirmed that the CuS in CuS@TiO2strongly withdraws the excited electrons from the valence band in TiO2because of the higher reduction potential than TiO2, resulting in a slower recombination rate between the electrons and holes and higher photoactivity.

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