| 摘要 |
PCT No. PCT/FR94/01489 Sec. 371 Date Oct. 3, 1996 Sec. 102(e) Date Oct. 3, 1996 PCT Filed Dec. 20, 1994 PCT Pub. No. WO95/18068 PCT Pub. Date Jul. 6, 1995The invention concerns a procedure for preparation of a precursor of a mixed cerium and zirconium oxide-based composition, characterized by the following steps: a liquid mixture is prepared containing cerium and zirconium compounds; the preceding mixture is placed in contact with carbonate or bicarbonate, thus forming a reactive medium exhibiting a neutral or basic pH during the reaction; the precipitate obtained is collected. A mixed cerium and zirconium oxide-based composition is obtained by calcining this precursor. This composition is characterized by the fact that it has a total pore volume of at least 0.6 cm3/g, and that at least 40%, and more particularly at least 50%, of the total pore volume is composed of pores having a diameter of at most 1 mu m.
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