초록 ▼

A composition based on cerium oxide and on zirconium oxide and, optionally, on a yttrium, scandium or rare-earth metal oxide. The cerium/zirconium atomic proportion is at least 1. The compound exhibits a specific surface, after calcination for 6 hours at 900.degree. C. of at least 35 m.sup.2 /g and

A composition based on cerium oxide and on zirconium oxide and, optionally, on a yttrium, scandium or rare-earth metal oxide. The cerium/zirconium atomic proportion is at least 1. The compound exhibits a specific surface, after calcination for 6 hours at 900.degree. C. of at least 35 m.sup.2 /g and an oxygen storage capacity at 400.degree. C. of at least 1.5 ml of O.sub.2 /g. The composition is prepared by mixing, in a liquid medium, a cerium compound, a zirconium compound and, if appropriate, a yttrium, scandium or rare-earth metal compound; heating and calcining the precipitate obtained; and using a zirconium solution having an amount of base necessary to reach the equivalent point during an acid/base titration of the solution having a molar ratio of OH.sup.- /Zr.ltoreq.1.65. The composition thus obtained is used in the manufacture of multi-functional catalysts.

대표청구항 ▼

[ What is claimed is:] [1.]1. Composition comprising a cerium oxide and a zirconium oxide in a cerium/zirconium atomic proportion of at least 1, wherein the composition exhibits a specific surface, after calcination for 6 hours at 900.degree. C., of at least 35 m.sup.2 /g and an oxygen storage capac

[ What is claimed is:] [1.]1. Composition comprising a cerium oxide and a zirconium oxide in a cerium/zirconium atomic proportion of at least 1, wherein the composition exhibits a specific surface, after calcination for 6 hours at 900.degree. C., of at least 35 m.sup.2 /g and an oxygen storage capacity at 400.degree. C. of at least 1.5 ml of O.sub.2 /g.