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[en] This book is the Journal of the Korean hydrogen energy society, which includes study on the improvement of the electrochemical characteristics of surface-modified V-Ti-Cr alloy by Ball-milling by Kim, Jin Ho; Lee, Sang Min; Lee, Ho; Lee, Paul S. and Lee, Jai Young, hydrogen generation from water using cds-zns photocatalysts by Heo, Gwi Suk, characteristics of Y-Hx Film by Cho, Young Sin; Kim, Sun Hee, and effect of Cu powder as a compacting material on the discharge characteristics of the negative electrode of Ni-MH battery by Jung, J. H.; Han, Y. S.; Yu, J. S.; Jang, K. J.; Lee, J. Y.
[en] An evaluation of the previous Chemical Processing Cell (CPC) testing was performed to determine whether the planned concurrent operation, or ''coupled'' operations, of the Defense Waste Processing Facility (DWPF) with the Salt Waste Processing Facility (SWPF) has been adequately covered. Tests with the nitricglycolic acid flowsheet, which were both coupled and uncoupled with salt waste streams, included several tests that required extended boiling times. This report provides the evaluation of previous testing and the testing recommendation requested by Savannah River Remediation. The focus of the evaluation was impact on flammability in CPC vessels (i.e., hydrogen generation rate, SWPF solvent components, antifoam degradation products) and processing impacts (i.e., acid window, melter feed target, rheological properties, antifoam requirements, and chemical composition).
[en] To support resolution of Potential Inadequacies in the Safety Analysis for the Savannah River Site (SRS) Tank Farm, Savannah River National Laboratory conducted research to determine the thermolytic hydrogen generation rate (HGR) with simulated and actual waste. Gas chromatography methods were developed and used with air-purged flow systems to quantify hydrogen generation from heated simulated and actual waste at rates applicable to the Tank Farm Documented Safety Analysis (DSA). Initial simulant tests with a simple salt solution plus sodium glycolate demonstrated the behavior of the test apparatus by replicating known HGR kinetics. Additional simulant tests with the simple salt solution excluding organics apart from contaminants provided measurement of the detection and quantification limits for the apparatus with respect to hydrogen generation. Testing included a measurement of HGR on actual SRS tank waste from Tank 38. A final series of measurements examined HGR for a simulant with the most common SRS Tank Farm organics at temperatures up to 140 °C. The following conclusions result from this testing.
[en] Hydrogen predominantly takes up interstitial positions, so it may be helpful to define the main interstitial sites. In addition, impurity atoms may share a lattice site with a silicon atom - the so-called split site configuration - oriented either along a (100) or a (110) axis, and these complexes may trap hydrogen atoms. Hydrogen is the subject of several recent reviews which discuss the whole field in the much greater depth than will be attempted here. Because much of the experimental data on single hydrogen came from muon spin resonance data, much of the modeling has included muonium as if it were a light isotope of hydrogen. Because of the lighter mass of muonium, and therefore higher zero point energy in whatever site it occupies, it is quite plausible that muonium is not trapped at a stable hydrogen site. The interpretation of muonium data and its relation to the properties of hydrogen have, therefore to be approached with care. (author)
[en] The Department of Energy, Office of Nuclear Energy, has requested that a Hydrogen Technology Down-Selection be performed to identify the hydrogen production technology that has the best potential for timely commercial demonstration and for ultimate deployment with the Next Generation Nuclear Plant (NGNP). An Independent Review Team has been assembled to execute the down-selection. This report has been prepared to provide the members of the Independent Review Team with detailed background information on the High Temperature Electrolysis (HTE) process, hardware, and state of the art. The Idaho National Laboratory has been serving as the lead lab for HTE research and development under the Nuclear Hydrogen Initiative. The INL HTE program has included small-scale experiments, detailed computational modeling, system modeling, and technology demonstration. Aspects of all of these activities are included in this report. In terms of technology demonstration, the INL successfully completed a 1000-hour test of the HTE Integrated Laboratory Scale (ILS) technology demonstration experiment during the fall of 2008. The HTE ILS achieved a hydrogen production rate in excess of 5.7 Nm3/hr, with a power consumption of 18 kW. This hydrogen production rate is far larger than has been demonstrated by any of the thermochemical or hybrid processes to date.
[en] Highlights: • Water splits at 0.8 V in a hybrid electrolyzer. • The hybrid electrolyzer contains basic and acidic compartments. • Hydrogen comes from the acidic compartment. • Oxygen comes from the basic compartment. • The hybrid electrolyzer breaks the thermodynamic limit for water splitting. Electrochemical water splitting normally requires a voltage between 1.6 and 2.5 V, due to the thermodynamic requirement (1.23 V at 25 °C), ohmic resistance and overpotentials on the anode and cathode. Here, we demonstrate a new concept that successfully splits water into oxygen and hydrogen at a voltage as small as 0.8 V at room temperature (25 °C) with earth-abundance catalysts. This concept breaks the thermodynamic requirement for water splitting and provides a bright future for the hydrogen economy.
[en] For the effective hydrogen generation from H2S, it should be compatible that the increscent of the photocatalytic (or electrochemical) activities and the development of effective utilization method of by-products (poly sulfide ion). In this study, “system integration” to construct the sulfur cycle system, which is compatible with the increscent of the hydrogen and or electron energy generation ratio and resource circulation, is investigated. Photocatalytic hydrogen generation rate can be enhanced by using stratified photocatalysts. Photo excited electron can be transpired to electrode to convert the electron energy to hydrogen energy. Poly sulfide ion as the by-products can be transferred into elemental sulfur and/or industrial materials such as rubber. Moreover, elemental sulfur can be transferred into H2S which is the original materials for hydrogen generation. By using this “system integration”, the sulfur cycle system for the new energy generation can be constructed
[en] Hydrogen was generated by the reaction of metal hydride with water. The variation of hydrogen generation with the kind of powders (milled MgH_2, and MgH_2 milled with various contents of MgO, MgCl_2 or Ni+Nb_2O_5) was investigated. MgH_2 powder with a hydrogen content of 6.05 wt% from Aldrich Company was used. Hydrogen is generated by the reaction of Mg as well as MgH_2 with water, resulting in the formation of byproduct Mg(OH)_2. For about 5 min of reaction time, milled 95%MgH_2+5%MgO has the highest hydrogen generation rate among milled MgH_2+x%MgO (x=0, 5, 10, 15 and 20) samples. Milled 90%MgH_2+10%MgCl_2 has the highest hydrogen generation rate among all the samples.