Metathetic copper concentrate enrichment

Abstract

In one aspect, the invention provides processes for producing an enriched copper concentrate from a copper-and-nickel-containing ore. Processes of the invention may include an initial step of comminuting the ore, to provide a ground ore comprising copper minerals and nickel minerals. The ground ore may be subjected to a floatation process, to separate the ground ore into distinct fractions, such as first and second concentrates. A first concentrate may for example be made up of copper-enriched-and-nickel-containing solids, while a second concentrate is made up of nickel-enriched-and-copper-containing solids. The floatation process may for example fractionate the ore so that the concentration of copper minerals is higher in the first concentrate than in the ore, and the concentration of the nickel minerals is higher in the second concentrate than the ore.

1 . A process for producing an enriched copper concentrate from a copper-and-nickel-containing ore, comprising:
 comminuting the ore to provide a ground ore comprising copper minerals and nickel minerals;   subjecting the ground ore to a floatation process, to separate the ground ore into a first concentrate comprising copper-enriched-and-nickel-containing solids and a second concentrate comprising nickel-enriched-and-copper-containing solids, wherein the concentration of the copper minerals is higher in the first concentrate than in the ore and the concentration of the nickel minerals is higher in the second concentrate than the ore;   subjecting the second concentrate to a hydrometalurgical extraction, to extract a copper-containing leachate from the second concentrate; and,   exposing the first concentrate to the copper-containing leachate under metathetic leaching conditions that are effective to increase the concentration of copper, and decrease the concentration of nickel, in the copper-enriched-and-nickel-containing solids, to provide the enriched copper concentrate.   
     
     
         2 . The process of  claim 1 , wherein the copper mineral and nickel minerals are selected from the group consisting of: CuS, covellite; Cu9S8 (Cu1.12S), yarrowite; Cu39S28 (Cu1.39S) spionkopite; Cu8S5 (Cu1.6S), geerite; Cu7S4 (Cu1.75S), anilite; Cu9S5 (Cu1.8S), digenite; Cu31S16 (Cu1.96S), djurleite; Cu2S, chalcocite; CuFeS2, Chalcopyrite; Cu5FeS4, Bornite; CuFe2S3, Cubanite; Ni3S4, Polydymite; NiS, Millerite; Ni3S2, Heazelwoodite; FeNi2S4, Violarite; Ni4.5Fe4.5S8, Pentlandite; Fe(Ni)7S8, Nickeliferrous; and Pyrrhotite. 
     
     
         3 . The process of  claim 1  or  2 , wherein the metathetic leaching conditions are optimized for maximum copper depletion from the copper-containing leachate. 
     
     
         4 . The process of  claim 1  or  2 , wherein the metathetic leaching conditions are optimized for maximum enrichment of copper concentration in the enriched copper concentrate. 
     
     
         5 . The process of any one of  claim 1  or  2 , wherein the average particle size of the copper-enriched-and-nickel-containing solids subjected to the metathetic leaching conditions is less than 100 μm. 
     
     
         6 . The process of any one of  claim 1  or  2 , wherein the average particle size of the copper-enriched-and-nickel-containing solids subjected to the metathetic leaching conditions is in the range of 5-30 μm. 
     
     
         7 . The process of any one of  claim 1  or  2 , wherein the metathetic leaching conditions comprise an average temperature in the range of ambient temperature to boiling point. 
     
     
         8 . The process of any one of  claim 1  or  2 , wherein the metathetic leaching conditions comprise an average temperature above boiling point. 
     
     
         9 . The process of any one of  claim 1  or  2 , wherein the metathetic leaching conditions are maintained for a metathetic leaching time in the range of 2 to 12 hours.