Patent ID: 7686866

Claim:
A process for recovering copper from chalcopyrite comprising the steps of: (a) contacting chalcopyrite with a solution containing ferric ions to cause oxidation of sulphur in the chalcopyrite, and thereby the release of part of the copper present in the chalcopyrite into the solution as copper ions, the rest of the copper being present in a remaining solid product; (b) contacting said solid product from step (a) with a solution containing ferrous ions to cause reduction of sulphur in the solid product to a minus two valence state, i.e., sulphide, and thereby the reduction of sulphur in the solid product to sulphide ions; (c) contacting a solid product containing the sulphide ions from step (b) with a solution containing ferric ions to cause oxidation of sulphur in the solid product, and thereby the release of at least part of the copper remaining in the solid product into the solution as copper ions; and (d) recovering copper from one or more of the solutions from steps (a) and (c).