A process for making copper foil directly from a copper-bearing material selected from the group consisting of copper ore, smelter flue dust, copper cement and copper-containing waste, said process including sequential steps (A), (B-1), (C-1), (B-2), (C-2), (D), (E), (F), (G), (H'), (H), (I) and (J), said process comprising:
- (A) contacting said copper-bearing material with an effective amount of at least one aqueous leaching solution to dissolve copper ions in said leaching solution and form a copper-rich aqueous leaching solution;
- (B-1) contacting said copper-rich aqueous leaching solution from step (A) with an effective amount of at least one copper-bearing water-insoluble extractant from step (C-2) to transfer copper ions from said copper-rich aqueous leaching solution to said copper-bearing extractant to form a copper-rich extractant and a first copper-depleted aqueous leaching solution;
- said extractant comprising (i) at least one oxime characterized by a hydrocarbon linkage with at least one --OH group and at least one .dbd.NOH group attached to different carbon atoms on said hydrocarbon linkage, (ii) at least one betadiketone, or (iii) at least one ion-exchange resin;
- (C-1) separating said copper-rich extractant from said first copper-depleted aqueous leaching solution, advancing said copper-rich extractant to step (D);
- (B-2) contacting said first copper-depleted aqueous leaching solution from step (C-1) with an effective amount of at least one copper-depleted extractant from step (E) to transfer copper ions from said first copper-depleted aqueous leaching solution to said copper-depleted extractant to form a copper-bearing extractant and a second copper-depleted aqueous leaching solution;
- (C-2) separating said copper-bearing extractant from said second copper-depleted aqueous leaching solution, recirculating said copper-bearing extractant to step (B-1);
- (D) contacting said copper-rich extractant from step (C-1) with an effective amount of at least one aqueous stripping solution to transfer copper ions from said copper-rich extractant to said stripping solution to form a first electrolyte solution and a copper-depleted extractant;
- (E) separating said first electrolyte solution from said copper-depleted extractant, recirculating said copper-depleted extractant to step (B-2);
- (F) advancing said first electrolyte solution from step (E) into an electrolytic cell equipped with at least one first insoluble anode and at least one first cathode, and applying an effective amount of voltage across said first anode and said first cathode to deposit copper metal powder on said first cathode, said first electrolyte solution containing impurities carded over from one or more of said contacting steps;
- (G) removing copper metal powder from said first cathode;
- (H') calcining said copper metal powder to form cuprous oxide, cupric oxide or a mixture thereof;
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- (H) dissolving said cuprous oxide, cupric oxide or mixture thereof from step (H') in a sulfuric acid solution to form a second electrolyte solution and placing said second electrolyte solution in an electroforming cell equipped with a second anode and a second cathode, said second cathode being a rotating cathode, said second electrolyte solution being characterized by the addition of one or more of an active-sulfur containing material, a gelatin, molasses, guar gum, a polyalkylene glycol, dithiothreitol, an amino acid, acrylamide, sulfopropyl disulfide, tetraethylthiuram disulfide, benzyl chloride, epichlorohydrin, chlorohydroxylpropyl sulfonate, an alkylene oxide, a sulfonium alkane sulfonate, thiocarbamoyldisulfide, selenic acid, or a mixture of two or more thereof;
- (I) flowing said second electrolyte solution between said second anode and second cathode, and applying an effective amount of voltage across said second anode and second cathode to deposit copper foil on said second cathode;
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- (J) removing said copper foil from said second cathode.