Support hydrous metal oxides

Dosch, R. G. Stephens, H. P. Stohl, F. V. U.S. Patent 4 511455,1985. Dosch, R. G. Stephens, H. P. Stohl, F. V. Bunker, B. C. Peden, C. H. F. Hydrous Metal Oxide-Supported Catalysts Part I. A Review of Preparation Chemistry and Physical and Chemical Properties Sandia National Laboratories Report SAND89-2399, February 1990. 

A series of new crystalline titanates (CT) are shown to have considerable potential as catalysts supports. For Pd supported catalysts, the catalytic activity for pyrene hydrogenation was substaniatially different depending on the type of CT, and one was substantially more active than Pd on hydrous titanium oxide (HTO). For 1-hexene hydrogenation the activities of the new CTs were approximately the same as for the hydrous metal oxide siqtports. Stereochemical effects, such as shape selective catalysis, ars to be occurring when pyrene is hydrogenated. 

CNTs were also demonstrated to be a perfect support for cheap transition metal oxides of poor electrical conductivity, such as amorphous manganese oxide (a-Mn02 H20) [5,96], The pseudocapacitance properties of hydrous oxides are attributed to the redox exchange of protons and/or cations with the electrolyte as in Equation 8.13 for a-Mn02 H20 [97] ... 

The dynamic membranes originally developed by Union Carbide are protected by three core patents U.S, 3977967, 4078112, and 4412921 (Trulson and Litz, 1976 Bibeau, 1978 and Leung and Cacciola, 1983) and their foreign equivalents. Those patents cover a broad range of metal oxides such as zirconia, gamma alumina, magnesia>alumina spinel, tantalum oxide and silica as the membrane materials and carbon, alumina, aluminosilicates, sintered metals, fiberglass or paper as the potential porous support materials. However, their marketed product, trade named Ucarscp membranes, focused on dynamic membranes of hydrous zirconium oxide on porous carbon support. 

One of the first metal oxides to be examined electrochemically on a diamond substrate was ruthenium dioxide [115, 116]. This material is important both for electrochemical capacitor and electrocatalytic applications (chlorine evolution). Another example is cobalt hydrous oxide, which has catalytic activity for oxygen evolution [117]. A very recent example is lead dioxide [118]. A metal oxide (V2O3) has also been supported on particulate diamond as a catalyst for an organic gas-phase reaction [119]. 

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