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:
Sep. 28, 1982
Filed:
Jan. 19, 1981
Applicant:
Inventors:
Assignee:
Amax Inc., Greenwich, CT (US);
Attorneys:
Primary Examiner:
Int. Cl.
CPC ...
C01G / ;
U.S. Cl.
CPC ...
423 61 ; 423 53 ; 423 58 ;
Abstract
A process for the soda ash digestion of scheelite concentrates is provided, the process comprising forming a slurry of a scheelite concentrate in an aqueous sodium carbonate solution and then digesting the slurry in an autoclave at an elevated temperature of at least about 180.degree. C. The concentration of the Na.sub.2 CO.sub.3 solution is substantially inversely correlated to the digestion temperature and substantially directly correlated to the Na.sub.2 CO.sub.3 /WO.sub.3 weight ratio such as to effect the selective dissolution of at least about 95% of the WO.sub.3 in the concentrate and provide a pregnant liquor containing WO.sub.3 while inhibiting substantial dissolution of gangue minerals.