Process for the removal of zinc and nickel from copper ammine sulfate solutions

A method for separating materials selected from the group consisting of zinc-containing materials, nickel-containing materials and mixtures thereof, from an aqueous copper ammine sulfate solution, comprising the steps of:

• (a) providing an aqueous copper ammine sulfate solution comprising cuprous ions, ammine ions, and sulfate ions and materials selected from the group consisting of zinc-containing materials, nickel-containing materials and mixtures thereof, ammonium sulfate, and free ammonia;
• (b) oxidizing said cuprous ions in said copper ammine sulfate solution to cupric ions to form a first cupric ion-containing solution;
• and
• (c) adjusting the pH of said cupric ion-containing solution to within the range from about pH 7.5 to about pH 8.0 to form a precipitate comprising zinc-containing materials, nickel-containing materials, and mixtures thereof, and to form a second cupric ion-containing solution relatively free of nickel and zinc.