PROCEDE DE PREPARATION DE SELS PRATIQUEMENT PURS D'OXYACIDES DEPHOSPHORE DE METEAUX DU GROUPE IV B DU TABLEAU PERIODIQUE

摘要

A process for the preparation of substantially pure phosphorus oxyacid salts of metals which comprises (a) reacting a compound of a metal of Group IV b containing metallic impurities with a phosphorus oxyacid or its reactive derivative in the presence of water; (b) separating the forming gelatinous precipitate of the phosphorus oxyacid salt of the metal of Group IV b from the mother liquor by filtration; (c) (i) converting the obtained filter cake to a fluid sol by means of shear agitation and then scattering the sol into a heating atmosphere to form a granular gel or (ii) drying the obtained filter cake, then pelletizing the dried cake to form a granular gel; and (d) extracting the granular gel of the phosphorus oxyacid salt of the metal of Group IV b with an acid or its vapor in the presence of water to thereby remove metallic impurities therefrom.