| 摘要 |
The invention relates to a process for the production of compositions based on mixed zirconium and cerium oxides having high and thermally stable specific surfaces, the said process being characterised in that it comprises the following stages: (i) a zirconium sol, on the one hand, and a cerium sol, on the other hand, are mixed in the stoichiometric proportions corresponding to those of the desired final composition, the ratio r of the mean diameter r1 of the particles constituting the zirconium sol to the diameter r2 of the particles constituting the cerium sol being at least 5, (ii) a base is added to the mixture thus obtained, (iii) the precipitate thus formed is recovered and finally (iv) the precipitate thus recovered is calcined. The invention also relates to the compositions based on mixed oxides of high specific surfaces (>10 m<2>/g) capable of thus being obtained and to their uses as, or for the manufacture of, catalysts and/or catalyst supports, in particular in the field of automobile afterburning. |
