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:
May. 25, 1982
Filed:
Apr. 13, 1978
Nathaniel Arbiter, Tucson, AZ (US);
Martin C Kuhn, Tucson, AZ (US);
Atlantic Richfield Company, Los Angeles, CA (US);
Abstract
Copper, nickel and zinc are recovered from sulfide minerals or concentrates thereof by leaching with ammonia at or near atmospheric pressure. A slurry of such minerals or concentrates in an aqueous solution containing free ammonia is passed into a closed leaching vessel or a series of such vessels into which oxygen is admitted. The slurry in such vessel or vessels is mechanically agitated with a vigor input of at least 0.05 horsepower per cubic foot and preferably while recirculating oxygen from above the slurry to well below its surface. The temperature of the slurry is maintained between 50.degree. and 100.degree. C. or up to the boiling temperature at the prevailing pressure, and the pH preferably is in the range from 9 to 11. Solids separated from the leach solution at the conclusion of such leaching operation may be releached for additional copper recovery by a similar leaching procedure in one or a series of leaching vessels. Recoveries of copper, nickel and zinc in the range from 90% to 95% can in many cases be obtained in a leaching time of 3 to 6 hours from ores and concentrates containing one or more of the minerals chalcocite, chalcopyrite, pentlandite and sphalerite. By similarly releaching the solid residue from the primary leaching operation, overall recoveries may in many cases be increased to 99%.