Process for producing zirconium sols and gels, and process for producing zirconia using the same

Abstract

A process for producing acidic boratozirconium chloride sols which comprises: reacting a zirconium compound with a boron compound in molar ratios of B/Zr of 0.3-1.2 together with a compound of a metal M other than boron, the metal M being selected from the group consisting of divalent, trivalent, tetravalent and pentavalent metals in molar ratios of M/Zr of about 0.01-1 in water in the presence of chloride ions in molar ratios of Cl/Zr of not less than about 1. The acidic boratozirconium chloride sol may be converted to basic boratozirconium sols by reacting the acidic sol with a basic carbonate compound such as ammonium carbonate. The sols, either acidic or basic, are readily gelled by contact with a dehydration solvent such as methanol or acetone. The gel is calcined at relatively low temperatures to provide zirconia which is either very pure or stabilized in varied degrees.

Dependencies are inferred from the claim text.