The role of copper ions in improving the flotation of chalcopyrite at low temperatures

It is of great significance to improve the flotation of copper sulfide minerals at low temperatures. In this study, the reduction mechanism of chalcopyrite flotation performance and the role of copper ions in improving the flotation of chalcopyrite at low temperatures were systematically investigated. The results of the flotation tests prove that the chalcopyrite flotation recovery is lower at low temperatures (5℃) than at room temperatures (20℃), which is directly related to the changes in the surface hydrophobicity. However, the addition of copper ions can effectively improve the chalcopyrite flotation at low temperatures. Electrochemical measurements indicate that copper ions positively affect the redox reaction and electron transport on the chalcopyrite surface at low temperatures, thereby increasing the current density and surface activity of chalcopyrite. Besides, X-ray photoelectron spectroscopy analysis and adsorption measurements clearly indicate that copper ions mainly adsorbed on chalcopyrite surface in the form of CuS species by chemisorption, thereby significantly enhancing the adsorption amounts of xanthate on the chalcopyrite surface and improving the flotation of chalcopyrite at low temperatures.