Activation and Leaching Of Chalcopyrite Concentrate

CIM Bulletin, 1973

K. N. SUBRAMANIAN and H. KANDUTH, Department of Extractive Metallurgy, Noranda Research Centre, Pointe Claire, Que.

It is well known that chalcopyrite can be dissociated into simple sulphides by heating with elemental sulphur at about 475°C: CuFeS2 + S -> CuS + FeS2 Experimental work was undertaken to determine whether this "activation" could be used to advantage in the selective leaching of copper from chalcopyrite concentrate. A method of treating copper concentrate with molten sulphur was developed and the activated product was leached in dilute sulphuric acid using oxygen, ferric iron or manganese dioxide as the oxidant. The object was to obtain a solution suitable for electrowinning with minimal purification, but it was impossible to obtain rapid extraction of copper without simultaneously dissolving a large proportion of iron. This was attributed to the fact that some of the copper was present as a low iron-copper sulphide (idaite) and that the pyrite formed during the "activation" step was more easily oxidized than natural pyrite.
Keywords: Chalcopyrite, chalcopyrite, Copper Leach Concentration, manganese dioxide, oxidizing agent, sulphuric acid, Concentrate, Concentrates, copper, Iron, leaching, Oxygen, sulphur