Thermally split zirconium silicate, method of its production and use

US5324355A · kind A · utility

Assignee

• Degussa AG · DE

Inventors

• Dieter Binder · Wien, AT
• Peter Kleinschmit · Hanau, DE
• Klaus Zetzmann · Kleinostheim, DE
• Hans Hoffmeister · Gelnhausen, DE

Key dates

• Filing date: Feb 27, 1992
• Grant date: Jun 28, 1994
• Expiry date: Feb 27, 2012

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01P2006/64
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

Thermally split zirconium silicate is produced such that the crystalline zirconium dioxide embedded in an amorphous silica phase exhibits an average grain or particle size (d.sub.50 value) in a range of 0.5 .mu.m to 3.0 .mu.m and a specific surface area (BET) in a range of 3 to 15 m.sup.2 /g when the silica is removed by leaching. The zirconium dioxide produced by this method is particularly suited for the production of zirconium silicate pigments with improved color characteristics. The thermally split zirconium silicate is also particularly well suited for processes used in the obtention of zirconium dioxide. The method of producing the thermally split zirconium silicate includes melting zirconium silicate in an induction melting furnace and cooling off a free falling stream of melt by blowing on it with a gas and/or spraying it with water.