Electrochemistry of sphalerite activated by Cu2+ ion
(Department of Mineral Engineering, Central South University of Technology, Changsha 410083,P.R.China)
Abstract: By means of thermodynamic analyses and electrochemical tests, the electrochemical behavior of sphalerite has been studied. Results show that in the weak alkaline or alkaline media, sphalerite will be oxidized to Zn(OH)2, ZnO2-2 and so on, which influences the flotation ability of sphalerite. When Cu2+ ion is introduced into the flotation system, due to the oxidation of Cu2S and CuS, a series of copper sulfide compounds such as Cu2S, Cu1.96S, Cu1.71~1.82S, Cu1.75S, Cu1.60S, Cu1.40S, Cu1.12S and CuS are produced on the sphalerite surface. The activating role of Cu2+ ion can be generalized as two points: the first, a series of activation components of copper sulfide containing different amount of copper are produced; the second, these activation components can prevent the sphalerite from overoxidizing.
Key words: sphalerite; activator; flotation