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:
Jul. 26, 1977
Filed:
Jun. 14, 1976
Alkis S Rappas, Arlington, MA (US);
J Paul Pemsler, Lexington, MA (US);
Kennecott Copper Corporation, New York, NY (US);
Abstract
Copper values are recovered from an acidic solution of solubilized cupric ions by the reduction of cupric copper to cuprous copper with hydrogen gas in the presence of a solid hydrogenation catalyst and in the presence of a cuprous ion stabilizing ligand. Catalyst poisoning by precipitation of copper metal on the surface of the catalyst during the reduction is avoided by controlling the ratio of Cu.sup.+/ligand/Cu.sup.+.sup.+ and by terminating the hydrogenation before copper metal precipitates on the catalyst. The solution containing the cuprous ions is separated from the solid catalyst and the cuprous ions are then disproportionated to produce copper metal and cupric ions. The removal of the last amounts of cupric ions from solutions, after several stages of reduction and disproportionation is achieved by allowing the cupric ions to precipitate on the catalyst as copper metal. The catalyst is then separated from the copper barren raffinate and regenerated by exposing it to a fresh pregnant cupric ion solution in the presence of a cuprous ion stabilizing ligand.