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:
Oct. 17, 1995
Filed:
Feb. 14, 1994
Gary L Simmons, Albuquerque, NM (US);
Santa Fe Pacific Gold Corporation, Albuquerque, NM (US);
Abstract
A process is provided for recovering gold from refractory sulfide ores. Preferred feed materials have multiple different sulfide mineralogies, with gold being primarily contained within one or more, but not all, of the sulfide mineralogies. Sulfide mineralogies with the highest gold values are preferentially oxidized, while those sulfide mineralogies with relatively little gold remain largely unoxidized. In one embodiment, dissolved arsenic following pressure oxidation is precipitated as ferric arsenate through the control of pH during neutralization. In another embodiment, the oxidized slurry following pressure oxidation is contacted with an oxidizing agent to convert at least a portion of ferrous iron to ferric iron. Following, pressure oxidation, the slurry can be subjected to cyanidation recovery of gold, and liquid from the tailings stream can be recycled upstream of the pressure oxidation step in a substantially untreated form. The process is useful for recovering gold contained as ultra-small masses in sulfide minerals.