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:
Feb. 18, 1986
Filed:
Mar. 03, 1983
Albert Bruynesteyn, North Vancouver, CA;
Ralph P Hackl, Burnaby, CA;
Richard W Lawrence, Vancouver, CA;
Andrew I Vizsolyi, Vancouver, CA;
British Columbia Research Council, Vancouver, CA;
Abstract
A process for leaching copper from copper sulphide containing ore, in particular copper from chalcopyrite containing ore, is provided. The ore is preferably initially ground up and mixed with an aqueous acid leaching medium containing sulphide oxidizing bacteria, and a bacterial nutrient, and a catalytic amount of silver. Provision is made in the bacterial nutrient for a source of carbon dioxide and oxygen for the bacteria, both of which may be supplied by means of sparging with carbon dioxide enriched air. A bacterial compatible acid is added initially to the ore and leaching medium mixture and periodically during the process so that sulphide in the copper sulphide is oxidized in stoichiometric amounts to elemental sulphur. During leaching the oxidation potential is maintained between about 0.54 to 0.66 volts, most readily by initial addition of thiosulphate and dissolved copper.