| 摘要 |
The invention concerns a colloidal dispersion in a continuous phase of a cerium compound and another element M selected among zirconium, rare earths (Ln) other than cerium, titanium and tin characterized in that the compound is in the form of a mixed oxide wherein the cerium and the element M are in solid solution. It comprises cerium in the form of cerium III in an amount expressed in cerium III/total cerium atomic ratio ranging between 0.005 and 0.06. The dispersion is obtained by forming a liquid medium comprising cerium salts, in particular of cerium III, and the element M; contacting the medium with a base to obtain a pH of not less than 9; separating and washing the resulting precipitate; peptizing by treating with an acid whereby the dispersion is obtained, the method further comprising a step of washing either after separating the precipitate or after peptization. |
