Method for the manufacture of pure aluminum oxide from aluminum ore

US4222989A · kind A · utility

Inventors

• Milan Belsky · Bonn, DE
• Albert Schwind · Bornheim, DE
• Gunter Winkhaus · Rübhausen, DE
• Joseph Schierholt · Neukirchen-Vluyn, DE

Key dates

• Filing date: Jan 26, 1979
• Grant date: Sep 16, 1980
• Expiry date: Jan 26, 1999

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01F7/22
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A process for obtaining pure aluminum oxide (Al.sub.2 O.sub.3) from siliceous aluminum ore is disclosed. The aluminum ore is digested in a hydrochloric acid solution to obtain aluminum chloride, the aluminum chloride is crystallized as the hexahydrate, the aluminum chloride hexahydrate is purified and, subsequently, decomposed to give pure aluminum oxide and secondary products. The mother liquor of the crystallization step and the secondary products of the decomposition step are recycled.