COMPOSITION BASED ON CERIUM OXIDE AND ZIRCONIUM OXIDE AND HAVING HIGH SPECIFIC SURFACE AREA AND HIGH

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PROBLEM TO BE SOLVED : To provide a composition having high specific surface area stability and oxygen storing potential stability and usable at a high temperature. SOLUTION : The composition is based on cerium oxide and zirconium oxide of at least one cerium/zirconium atom ratio and properly based on yttrium, scandium or rare earth metal oxide and the composition exhibits a specific surface area of at least 35 m2/g after calcination at 900°C for 6 h and oxygen storing potential of at least 1.5 ml/g O2 at 400°C. The composition is manufactured by mixing a cerium compound, a zirconium compound and properly yttrium, scandium or rare earth metal compound, heating the mixture and calcining an obtained precipitate. The mixture is prepared by using a zirconium solution and an amount of a base required to reach an equivalence point when the solution is subjected to acid/base titration satisfies a molar ratio condition of OH-/Zr ≤ 1.65.