In oxygen production from water

Metalloporphyrins electrical properties, 144 in oxygen production from water, 522 photochemical properties, 510 in photoproduction of hydrogen from water, 511, 510-513 structure, 615 Mctallothioncins cobalt(II), 673 copper and zinc storage, 672 EXAFS, 673 mammals... 

The standard potential for the anodic reaction is 1.19 V, close to that of 1.228 V for water oxidation. In order to minimize the oxygen production from water oxidation, the cell is operated at a high potential that requires either platinum-coated or lead dioxide anodes. Various mechanisms have been proposed for the formation of perchlorates at the anode, including the discharge of chlorate ion to chlorate radical (87—89), the formation of active oxygen and subsequent formation of perchlorate (90), and the mass-transfer-controUed reaction of chlorate with adsorbed oxygen at the anode (91—93). Sodium dichromate is added to the electrolyte ia platinum anode cells to inhibit the reduction of perchlorates at the cathode. Sodium fluoride is used in the lead dioxide anode cells to improve current efficiency. 

Because of the possible importance of the process for the production of a liquid motor fuel from coal and the possible bearing it might have on the synthesis of oxygenated products from water-gas, a considerable amount of research has been expended on the problem both in this country and abroad.111 The reverse reactions, however, are of limited importance since at the temperatures required, the aliphatic hydrocarbons higher than methane undergo decomposition reactions in the presence of the active catalysts. 

The Fischer-Tropsch aqueous product was not further refined and was treated as a wastewater stream. This was in line with the simplicity of the refinery design, poor economy of scale for oxygenate recovery, and inherently low water-soluble oxygenate production from Co-LTFT synthesis. 

Biorefineries New catalytic pretreatment of plant materials Valorization, pretreatment or disposal of co-products and wastes from biorefinery by catalytic treatments New and/or improved catalytic processes for chemicals production through the integration of the biorefinery concept and products into the existing chemical production chain New advanced catalytic solutions to reduce waste emissions (solid, air and, especially, water) New catalysts to selectively de-oxygenate products from biomass transformation Catalysts to selectively convert chemicals in complex multicomponent feedstocks New biomimetic catalysts able to operate under mild conditions Small catalytic pyrolysis process to produce stabilized oil for further processing in larger plants... 

Oxygen may be produced by electrolysis of water. In such electrolytic procedure, small amounts of H2SO4 or NaOH may be added to water. Electrolysis methods, however, are not used as much commercially as are air bquefaction processes which cost less. However, in making hydrogen from water by electrolysis, oxygen is obtained as a by-product. 

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