Abstract

The reaction of chalcopynte with gaseous sulfur has been investigated in the range 350-450 °C in order to transform this mineral into a more acid soluble copper sulfide and insoluble iron sulfide. The results of thermodynamic analysis of this system as well as the X-ray diffraction analysis of the reaction products showed that in the temperature range 350 400°C the sulfidation reaction proceeded without formation of intermediate copper-iron sulfides according to: CuFeS 2 + 1/2S 2(g) = CuS + FeS 2 The effects of temperature and time on the conversion of chalcopyrite were studied. Conversion of chalcopyrite reached about 80% very rapidly with increase in temperature up to about 400 °C. The recovery of copper from the sulfidized samples was determined by leaching in oxygenated 1.2M H 2SO 4, 2M NaCl solution. Copper recoveries over 90 % were obtained from samples sulfidized for 30 min at temperatures lower than 400 °C.