Sulfidation of chalcopyrite with elemental sulfur

The sulfidation of chalcopyrite concentrate with elemental sulfur was studied in the temperature range of 325 °C to 500 °C. The effects of temperature, time, and composition of the reactants on the sulfidation were determined. The X-ray diffraction (XRD) and light microscopic analyses showed that the sulfidation of chalcopyrite forms CuS and FeS₂ at temperatures below 400 °C. However, at temperatures above 400 °C, Cu₅FeS₆ and FeS₂ were formed. The sulfidation of chalcopyrite proceeds mainly through the gaseous phase, and temperature has a significant influence on the sulfidation rate in the range of 325 °C to 400 °C. The extraction of copper from the reacted material was determined by leaching in an H₂SO₄-NaCl-O₂ system. Over 90 pct of copper could be extracted by leaching at 100 °C for 60 minutes in the mentioned system.