Colloidal dispersions of compounds of cerium and at least one of zirconium, rare earths, titanium and/or tin, dispersible solid based on said compound, and preparation methods

• Main Author: CHANEING JEAN YVES
• Format: Patent
• Language: English
• Published: 03.06.2015
• Subjects: CHEMICAL OR PHYSICAL PROCESSES, e.g. CATALYSIS OR COLLOIDCHEMISTRY; CHEMISTRY; COMPOUNDS OF THE METALS BERYLLIUM, MAGNESIUM, ALUMINIUM,CALCIUM, STRONTIUM, BARIUM, RADIUM, THORIUM, OR OF THERARE-EARTH METALS; INORGANIC CHEMISTRY; METALLURGY; PERFORMING OPERATIONS; PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL; THEIR RELEVANT APPARATUS; TRANSPORTING

Colloidal dispersions, in a continuous phase, contain a compound of cerium and another element M selected from among zirconium, rare earths (Ln) other than cerium, titanium and tin, wherein such compound is in the form of a mixed oxide in which the cerium and the element M are in solid solution; the cerium is in the form of cerium III in an amount expressed in cerium III/total cerium atomic ratio ranging between 0.005 and 0.06 and the dispersion is produced by forming a liquid medium comprising cerium salts, in particular of cerium III, and the element M, contacting the medium with a base to provide a pH of not less than 9, separating and washing the resulting precipitate and peptizing same by treating with an acid whereby the dispersion is obtained. The method further includes a step of washing after separating the precipitate or after the peptizing.