CATALYTIC COMPOSITION BASED ON CERIUM OXIDE AND MANGANESE OXIDE, IRON OR PRASEODYME, PROCESS FOR PREPARING THE SAME AND USE THEREOF IN CATALYSIS AUTOMOBILE POSTCOMBUSTION

摘要

A catalytic composition based on a cerium oxide and at least one other oxide selected from iron, manganese or praseodymium oxides. The composition may be prepared by forming a liquid mixture containing a cerium compound and at least one iron, manganese or praseodymium compound; precipitating the mixture by heating it or adding a base; recovering the precipitate and calcining it. An alternative method comprises providing a liquid mixture containing a cerium sol and at least one compound of the other element, and proceeding as before. A final method comprises impregnating a cerium oxide with a solution of at least one compound of the other element, and calcining the impregnated cerium oxide. Said composition is useful for controlling H2S emissions in motor vehicle post-combustion catalysis.