Mechanism of influence of chloride ions on electrogenerative leaching of sulfide minerals

Abstract

A dual cell system was used to study the influence of chloride ions on the electrogenerative leaching of sulfide minerals. The results show that the influences of chloride ions on a series of electrogenerative leaching system are similar, and chlorine ion is involved in the electrogenerative leaching process of sulfide minerals directly. The output power increases with the increase of Cl⁻ concentration. The influence on the electrogenerative leaching rate decreases when the Cl⁻ concentration reaches a certain value. The mechanisms of anodic reaction are deduced based on the reasonable hypothesis, and kinetic equations with respect to chlorine ions for each sulfide mineral are obtained. The kinetic equations show that when concentration of Cl⁻ is relatively low, the electrogenerative leaching rates are predicted to have 2/5, 2/7, 1/3 and 1/3 order dependence on Cl⁻ concentration for chalcopyrite concentrate, nickel concentrate, sphalerite and galena. As concentration of Cl⁻ increases, the correlative dependence of electrogenerative leaching rate on concentration of Cl⁻ becomes weak.

Keywords

chloride ion / electrogenerative leaching / mechanism / sulfide minerals

References

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