Experts who deal with copper and nickel know that copper and nickel are two closely related metals. Copper often can be found in the nickel-bearing ore, while nickel is always present in the copper-bearing ore. However, industries will always separate the two metals other than end up with an alloy of the two in the process of smelting and refining. In the last several decades, different methods have been found out to separate the two metals, which are sort of expensive in some degree. This is one of the method used that is cheaper

At the beginning, you need to prepare an ore composed of copper and nickel. Then, find some equipment to crush and grind the ore, and separate out the worthless material by the method of flotation, which will leave you a concentrate that typically composed by 2%-10% nickel and 5%-20% copper .

Next, you need to smelt the concentrate in a reverberating furnace or some other equipment. And the smelted material is defined as matte by metallurgists. Then wait until the matte cools down, during which time, particles of copper sulfide, nickel sulfide, and a metallic fraction will be formed.

In the end, you can recover the metals by means of crushing, grinding, flotation and magnetic separation. Besides, leaching one or two metals from the matte also can be used to separate the copper and nickel. Acid leaching can dissolve and separate out copper while oxidizing the matte can be used to leach our nickel.

How much of this alloy are you trying to separate??

Is this alloy present in a native mineral or as a proper alloy produced from a pyrometallurgical process??

The amount of material and how it is generated is important as generally separating these metals is much easier using hydrometallurgical routes rather than pyrometallurgy.

A sensible answer is difficult without knowing the basics, ie the questions above. 

You may dissolve the alloy by some methods like acid leaching and obtain a solution containing copper and nickel ions, then copper and nickel could readily be separated by solvent extraction.

If understood well, problem is separating Cu and Ni from alloy, not ore... generally this mean that you will have certain amount of material, instead some tromendous amount of material to be processed, why probably best and most economical procedure to go for is hydrometallurgy.

In this sense you will have to use some of common hydrometallurgical methods (acid leaching), either selective electrowininig or combination of  Ni cementation and Cu recovery by electrowinning (this would involve additional Ni refining step). If your material is pure Ni-Cu alloy, other route may be employment of amonia solutions highly selective to Cu...

Dear Prof Zhou,

under which condition you do the solvent extraction of copper and nickel?

kind regards

Dr. Rüdiger B. Richter

The leaching of lthe alloy is not easy. The leaching method must use a strong oxidative reagent like oxygen (autoclave) or HNO3 acid (high cost of equipment). The cheapper method is the electrorefining of coppet. The alloy will be the anode and the copper will deposited on the cathode. The nickel will remain in solution. From the bleed solution of copper electrorefining, nickel nickel will be obtained after purification process