The method of nickel and copper separation in the processing of wastewater containing nickel and copper trace elements has been developed and investigated. The method provides collective foam flotation extraction of nickel and copper by naphthenic acid solution in kerosene with subsequent selective re-extraction of nickel from the obtained organic phase of the foam product. The optimum conditions for selective re-extraction were determined: temperature 70 °C and pH = 375-425 Under these conditions the partition coefficient of nickel and copper reaches 140-145, which makes it possible to obtain after crystallization commercial nickel sulfate corresponding to the copper content in grade Ch of GOST 4465-74.
