The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jul. 06, 1982
Filed:
Jan. 19, 1981
Robert F Hogsett, Arvada, CO (US);
Dale K Huggins, Golden, CO (US);
Leo W Beckstead, Arvada, CO (US);
Amax Inc., Greenwich, CT (US);
Abstract
A process for conditioning a tungsten concentrate containing tungsten as WO.sub.3, sulfur as sulfide, and calcite to fix at least a portion of the sulfur as calcium sulfate by reaction with the calcite, comprises providing a tungsten concentrate having a calcite content such that less than about 15 wt. % calcium sulfate based on the weight of the WO.sub.3 in the concentrate will be formed and heating the concentrate to a temperature of at least about 500.degree. C. in an oxidizing atmosphere to oxidize substantially all the sulfur in the concentrate to provide a conditioned concentrate having a calcium sulfate content less than about 15% based on the weight of the WO.sub.3, whereby the conditioned concentrate can be efficiently leached with alkali metal carbonates or hydroxides and the resulting alkali metal tungstate solution can be effectively treated to recover an ammonium tungstate solution.