An electrochemical investigation on collectorless flotation of sphalerite in presence of Cu2+ ions
(1.Department of Environment and Resources Engineering,Guangdong University of Technology, Guangzhou 510090,P.R.China2.Tongji University, ,Shanghai 200092,P.R.China)
Abstract: The collectorless flotation behaviors of sphalerite in the presence of Cu2+ ions have been established. The effects of pH, potential and Cu2+ concentration on the flotation have been studied using a micro flotation cell specially designed, where the potential can be controlled by a potentiostat. The flotation results have shown that the Cu activated sphalerite displays a good collectorless floatability in a pH range of 0～13. The higher potentials can improve the flotation recovery. The surface species formed during the Cu ion activation have been examined using a special electrochemical technique—a composite sphalerite electrode. Zinc deficient sulfide (Zn1- xCuxS) and Cu poly sulfide (Cuy+zSy) species have been determined. They are responsible for the collectorless flotation of sphalerite. In additional, they can improve the conductivity of the sphalerite surface.
Key words: collectorless flotation； sphalerite； copper activation； electrochemical measurement