COMPOSITION BASED ON OXIDES OF ZIRCONIUM, CERIUM, YTTRIUM, LANTHANUM AND OF ANOTHER RARE EARTH, METHOD FOR PREPARING SAME AND CATALYTIC USE;

摘要

COMPOSITION BASED ON OXIDES OF ZIRCONIUM, CERIUM, YTTRIUM, LANTHANUM AND OF ANOTHER RARE EARTH, METHOD FOR PREPARING SAME AND CATALYTIC USE The invention concerns a composition based on zirconium oxide in a weight proportion of at least 25%, and comprising between 15% to 60% of cerium oxide, between 10% and 25% of yttrium oxide, between 2% and 10% of lanthanum oxide and between 2% and 15% of another rare earth oxide. Additionally, it has, after calcinations for 10 hours at 1150°C, a specific surface of at least 15 m2/g as well as a cubic phase. It is obtained by forming a mixture comprising zirconium, cerium, yttrium, lanthanum and the additional rare earth, by precipitating said mixture with a base, heating in aqueous medium said precipitate, adding thereto a surfactant and calcining the precipitate. Said composition can be used as catalyst.