| Arsenic is usually found in enargite（Cu3As S4）and tennatite(Cu12As4S13).They are often closely associated with copper sulphide ores.The floatability of enargite is similar to other sulfide copper ores.Flotation cannot achieve copper-arsenic separation.This leads to serious environmental pollution during subsequent further processing.In this paper,the oxidation behavior of chalcopyrite,chalcocite and enargite electrodes in alkaline environment under different potential conditions and the surface structure characteristics were analyzed in depth by using electrochemical research methods for neutral and weak alkaline systems,combined with thermodynamic theory analysis and calculation,and surface spectroscopy detection.The results showed that the oxidation resistance of the three types of minerals in alkaline environment was ranked as follows:enargite>chalcopyrite>chalcocite.Chalcopyrite and chalcocite have higher polarization resistance at p H=10.09.Relatively stable passivation films were formed on the surface.Raman and XPS analysis showed that chalcopyrite surface was completely oxidized to form copper oxides and Fe OOH at 600 m V.At 500 m V,the surface reaction of chalcocite is more active and the surface copper-bearing phase is copper oxide or copper hydroxide.At 600 m V,arsenic sulfides and copper sulfides are found on the surface of enargite.They make the mineral surface hydrophobic.In summary,at p H=10.09 and the potential of 600 m V,the surface of enargite is partially oxidized by Cu（II）-S and As（V）-S oxidation products.Enargite still has partially hydrophobic.Chalcopyrite and chalcocite are completely oxidized on the surface at this time to form copper（iron）hydroxide.It makes the mineral surface hydrophilic.Theoretically,the differential oxidation of chalcopyrite,chalcocite and enargite can be completed to realize the flotation separation of"copper-suppressed arsenic flotation". |
