Patent ID: 6309531
Filing Date: 2001-10-30
Classification: C22B,C25C,Y02P

Abstract:
A chemical process for extracting copper or iron from a metallic substrate comprising:a. exposing the copper or iron (M) containing substrate to a leaching solution comprising a metal salt (m) wherein the substrate is insolvable in the metal salt solution, such that the copper or iron is solvated from the substrate and the metal ion is reduced according to the reaction2m.sup.+3.sub.(aq) +M.sub.(s).fwdarw.2m.sup.+2.sub.(aq) +M.sup.+2.sub.(aq) ;b. providing an electrolytic cell with an anion exchange membrane that separates the anode from the cathode, thereby creating an anode chamber and a cathode chamber;c. transferring the leaching solution with the solvated copper or iron into the cathode chamber of the electrolytic cell;d. adding a second solution to the anode chamber, wherein the second solution comprises a reduced state metal salt m.sup.+2 of the salt in the leaching solution;e. applying a voltage to the cell wherein the copper or iron is reduced and is removed from the metallic substrate leaving the metallic substrate substantially unaltered and is deposited at the cathode and the reduced metal m.sup.+2 is oxidized at the at the anode;f. recycling the oxidized metal m.sup.+3 in the anode chamber to step (a) in order to solvate further amounts of copper or iron; andg. transferring the cathode chamber reduced-metal-containing solution to the anode chamber as the second solution of step (d).