摘要 |
New compositions based on ceric oxide exhibiting an improved ability to store oxygen, these compositions being characterised in that, besides ceric oxide, they contain at least one oxide of another metallic element M chosen from the group consisting of iron, bismuth, nickel, tin and chromium or one of their mixtures, this oxide being preferably in solid solution with the abovementioned cerium oxide. The process for the synthesis of these compositions consists in first of all preparing an intimate mixture of (i) a ceric oxide or hydroxide and (ii) at least one additive consisting of a hydroxide or a salt capable of being thermally decomposed to oxide, of the metallic element M, and in then calcining this mixture so as to obtain the desired oxide-based composition. The compositions according to the invention are particularly useful in the manufacture of catalysts and/or catalyst supports, especially those intended for the treatment of the exhaust gases of internal combustion engines. |