Oxide as supports

Rhodium is a unique metal since it can catalyze several transformations.222,223 It is an active methanation catalyst and yields saturated hydrocarbons on an inert support. Methanol is the main product in the presence of rhodium on Mg(OH)2. Transition-metal oxides as supports or promoters shift the selectivity toward the formation of C2 and higher oxygenates. 

The use of various methods (coprecipitation, impregnation and deposition-precipitation) confirmed the superiority of the transition metal oxides as supports,69 these being more easily reducible than the ceramic oxides that gave low activities (Table 6.6). With mixed Fe2C>3-MgO supports activity increased with iron content, not withstanding a growth in gold particles size.69... 

The even spreading of an oxide over another oxide as support has been widely investigated. Depending on the coverage, different types of species are deposited. 

Olguin, E., Vrinat, M., Cedeno, L., Ramirez, I., Borque, M., and Lopez-Agudo, A. The use of Ti02-A1203 binary oxides as supports for Mo-based catalysts in hydrodesulfurization of thiophene and dibenzothiophene. Applied. Catalysis. A, General, 1997, 165, 1. 

Early transition metal carbides are catalyticaUy active for a variety of reactions. Since they are refractory and of high surface area, they could also be promising alternatives to oxides as supports for heterogeneous catalysts. Only a few investigations have used them for this purpose. And in these limited investigations, the metals were loaded onto intentionally passivated Mo C powders due to their high pyrophoricity. 

The use of inorganic oxides as support material has expanded continuously since the first report of the encapsulation of metal phtalo-cyanines inside the zeolite Na-Y was published in 1977. Microporous... 

Binninger T, Fabbii E, Koetz R (2013) Iridium-titanium oxide as support for Pt catalyst in PEMFC cathodes. ECS Trans 58 1835-1841... 

Oxides, as supports of ruthenium catalysts, have high mechanical strength, good stability and highly basic sites, which can provide electrons in order to activation of N2 and enhance the catalytic activity of synthetic ammonia. However, the low dispersion of ruthenium is a common problem. Therefore, it is a common topic on how to increase the dispersion of ruthenium. 

Manganese oxide, as supported and as bulk metal oxide, has also been studied for the catalytic combustion of aromatic VOCs. The performance of an - -Al203... 

Cherian, M., Rao, M.S., and Deo, G. Niobium oxide as support material for the oxidative dehdrogenation of propane. Catal Today 2003, 78, 397-409. 

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