Liquor oxalate stabilizers

US5385586A · kind A · utility

Assignee

• Nalco Chemical Company · US

Inventors

• Graeme J. Farquharson · Elmore, AU
• John D. Kildea · Mandurah, AU
• Anthony E. Gross · McLeansboro, US
• Stephen Charles Grocott · Calle de la Era, AU

Key dates

• Filing date: Mar 17, 1994
• Grant date: Jan 31, 1995
• Expiry date: Mar 17, 2014

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01F7/145
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A method for inhibiting the precipitation of sodium oxalate crystals in a Bayer process liquor. The method comprises the step of adding to the Bayer process liquor, after red mud separation and immediately prior to crystallization of alumina trihydrate, or during crystallization of alumina trihydrate, or during classification of alumina trihydrate, an effective amount of a cationic, surface active, alkylammonium salt compound.