| 摘要 |
A high temperature stable catalyst is made with fine particles of a base metal such as chromium, hafnium and niobium or their oxides dispersed throughout a matrix made of composite particles having at least one platinum group metal on a ceria promoted, high temperature chemically stabilized refractory oxide powder. The refractory oxide powder can be either alumina, alumina powder which has been calcined at a temperature near incipient alpha alumina formation, silica-alumina or zirconia. The base metal or base metal oxide comprises about 15% to 90% by weight of the total weight and the platinum group metal comprises 0.05% to 10% by weight of the total weight. The catalyst composition can be applied as a washcoat to conventional substrates or it can be formed into shaped catalysts. The washcoat is made by mixing together one slip containing the composite particles with a second slip containing the base metal or base metal oxide particles.
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