Hydrogen production parameters

The stereoisomers of olefin saturation are often those derived by cis addition of hydrogen to the least hindered side of the molecule (99). But there are many exceptions and complications (97), among which is the difficulty of determining which side of the molecule is the least hindered. Double-bond isomerization frequently occurs, and the hydrogenation product is the resultant of a number of competing reactions. Experimentally, stereochemistry has been found to vary, sometimes to a marked degree, with olefin purity, reaction parameters, solvent, and catalyst 30,100). Generalizing, it is expedient, when unwanted products arise as a result of prior isomerization, to avoid those catalysts and conditions that are known to favor isomerization. 

Not only the silane depletion, but also the hydrogen production can be used to obtain information on the reaction products of the decomposition process. In Figure 33 the silane depletion and the corresponding hydrogen production are shown for a number of experiments, with process parameters such as to cover both the a- and the y -regime [163, 301], A clear correlation exists. In addition. 

Thus we have conducted work on the structural parameters of coal hydrogenation products using the method of Brown-Ladner (1), and from the results obtained we have developed correlations of the reaction. Based on the above, the outline of the reaction mechanisms have been previously discussed and our results have been reported (2, 3J. ... 

Performance parameters of the electrolysis include the applied voltage, E (V), the applied current, I (A), and the hydrogen production rate, Q (Nt/h) at the reference condition of 0.1 MPa (1 bar) and 273 K (0°C). The Faraday efficiency, cr, expressed in Equation 4.6, is the ratio of AG to the applied power, I E, that is, the ratio of the theoretical electric power needed for the electrolysis to the actually applied power of the cell. Thus, the Faraday efficiency is one useful measurement to judge electrolysis performance. 

Within the reaction parameters used, the nickel catalyst is highly selective towards carbonylation. With the exception of trace a-mounts of methane formed, no other hydrogenation product is found. This is in contrast with cobalt whose carbonylation catalytic activity is enhanced by hydrogen but generally associated with aldehyde formation and homologation. 

We have studied photocatalytic properties of nanostructured metal-semiconductor composites, made from mesoporous samples of Ti02 and a number of metals (Cu2+, Ni2+, Co2+, Cd2+, Fe2+, Ag+, Zn2+, Pb2+) in hydrogen evolution from water-ethanol solutions. Correlations between the quantum yields of the photoreaction and various parameters of the reacting system (such as the metal nature and concentration, photocatalyst quantity, light intensity, temperature) have been found and discussed. It has been shown, that maximal quantum yield of hydrogen production (y = 0.44) could be achieved in case of Ti02/Cu composite. 

Typical Design Parameters for HTSR for 10 MM scf/d Hydrogen Production... 

SULFUR CYCLE HYDROGEN PRODUCTION SYSTEM MAJOR PROCESS PARAMETERS FOR A COMMERCIAL SYSTEM... 

Sensitivity of Results of Cost Analysis for Hydrogen Production Pathways to Various Parameter Values, 50... 

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