Flotation Separation of Chalcocite from Pyrite Using Controlled Redox Potential

A controlled potential flotation separation of chalcocite from pyrite using potassium ethyl xanthate (PEX) as a collector was investigated at different pH values. It was found that the oxidation-reduction state of the pulp can have a pronounced influence on the flotation separation of these minerals. Potential range between -100 mV to 0 mV (SHE) at pH 11 was found as optimum condition for separation of chalcocite from pyrite. Cyclic voltammetry method was used to identify the flotation behavior of these minerals. According to flotation results and cyclic voltammetry curves, appropriate separation of chalcocite from pyrite at above mentioned condition attributed to the formation and stability of copper-xanthate species which is responsible for the flotation of chalcocite and the instability or lack of dixanthogen that is responsible for the flotation of pyrite.