PROCESS FOR PREPARING A SOL-GEL FROM AT LEAST THREE METAL SALTS AND USE OF THE PROCESS FOR PREPARING A CERAMIC MEMBRANE

摘要

Process for preparing a sol-gel from at least four salts of metals M1, M2, M3 and M4 suitable and intended for the preparation of a perovskite type material corresponding to the general formula (I): A(1-X) A'x B(1-y-U) B'y B"u Omicron3-delta, (I), said process comprising the following steps: - a step a) of preparing an aqueous solution of water-soluble salts of said elements A, A' optionally A", B and B', in the stoichiometric proportions necessary for obtaining the material as defined above; - a step b) of preparing an aqueous-alcoholic solution of at least one non-ionic surfactant in an alcohol chosen from methanol, ethanol, propanol, propanol, isopropanol or butanol, mixed with an aqueous solution of ammonia in a sufficient proportion to ensure the complete solubilisation of said non-ionic surfactant in said aqueous-alcoholic solution, the concentration of said non-ionic surfactant in said aqueous-alcoholic solution being less than the critical micelle concentration; - a step c) of mixing said aqueous solution prepared in step a) with said alcoholic dispersion prepared in step b) in order to form a sol; - a step d) of drying said sol obtained in step c), by evaporation of the solvent, in order to obtain a sol-gel. Use of the process for preparing a ceramic membrane.