COMPOSITION BASED ON OXIDES OF ZIRCONIUM, CERIUM AND LANTHANUM AND OF YTTRIUM, GADOLINIUM OR SAMARIUM, WITH HIGH SPECIFIC SURFACE AND REDUCIBILITY, PREPARATION METHOD AND USE AS A CATALYST

摘要

The composition of the invention consists essentially of oxides of zirconium, cerium and lanthanum and of another rare earth chosen from among yttrium, gadolinium and samarium with a proportion of the lanthanum oxide and the oxide of the other rare earth of at least 15%, and has specific surfaces of at least 40 m²/g and at least 15 m²/g after calcination respectively for 4 hours at a 1000°C and 10 hours at 1150°C. After calcination for 10 hours at 1200°C it has a surface of at least 7m²/g. This surface is at least 5 m²/g for an embodiment in which after 10 hours of calcination at 1150°C the composition is in the form of a pure solid solution. This composition can be used as a catalyst or a catalyst support.