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:
Jan. 12, 1993
Filed:
Jan. 30, 1991
Applicant:
Inventor:
Kazi E Haque, Ottawa, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
C22B / ;
U.S. Cl.
CPC ...
75428 ; 75741 ;
Abstract
A process is disclosed for the direct recovery of gold from cyanide leach liquor, thiourea leach liquor or Bio-D leach liquor. The process comprises reduction precipitation of the gold from solution by the addition of stabilized alkali metal borohydride, preferably sodium, potassium, lithium or ammonium borohydride, at ambient temperature and pressure. High purity gold is obtained by heating the reduced precipitate to about 1200.degree. C. The barren solution is in a condition such that it can be recycled to the upstream process.