Abstract: The invention relates to a method for the preparation of metallic oxides. The method is carried by controlled hydrolysis of metallic alkoxides using an alkoxide emulsion which contains hydrophobic water/solvent reverse micelles and a surfactant, then submitting the polymer gel obtained to thermal treatment. In order to prepare metallic oxides layers, the reaction product is coated on a support when hydrolysis is only partial.

Abstract: The present invention relates to a method of manufacturing a medium for microfiltration, for ultrafiltration, or for reverse osmosis, wherein hydrolysis is performed on an alkoxide, an organo-metallic compound, or a metal salt of an organic or an inorganic acid, optionally dissolved in an anhydrous organic solvent, in order to obtain a sol of particles of the oxide or of the hydroxide of the corresponding chemical element, a thickening agent is added to the sol, and the resulting sol is slip cast onto a support layer having pores which are larger than pores desired for the filter medium, the thin layer deposited on the support medium is then dried, and then heat treated to eliminate the thickening agent and to sinter the particles of the deposited thin layer. The thickening agent is added to the sol in conjunction with a strong acid whose anion does not form a complex with ions of the oxide or hydroxide metal, and the slip casting is performed by mere putting into contact without filtering.