Removal of carbonate from caustic sulfide solution

US5164171A · kind A · utility

Assignee

• GTE Products Corporation · US

Inventors

• Michael J. Miller · Towanda, US
• Martin Vogt · Heilbronn, DE
• Thomas A. Wolfe · Towanda, US

Key dates

• Filing date: Jul 1, 1991
• Grant date: Nov 17, 1992
• Expiry date: Jul 1, 2011

Classification

• Technology area (CPC C): Chemistry; Metallurgy
• CPC primary: C01G41/00
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

In the manufacture of ammonium paratungstate, sulfide is added to a tungsten-containing solution in order to precipitate molybdenum sulfide. Volatiles, including sulfides, evolved during this process are collected in a caustic scrubbing solution. The sulfide values in the caustic scrubbing solution may be reused to precipitate molybdenum sulfide by first treating the caustic scrubbing solution with alkaline earth chloride or sulfate to precipitate out alkaline earth carbonate.