Flotation Separation of Covellite and Enargite via Oxidation Treatment

Abstract

The flotation separation of enargite from copper sulfide minerals is difficult owing to the similar floatability and reagent adsorption characteristics of these minerals. In this study, the effect of oxidation treatment using NaClO flow with FeCl3 on the flotation separation of covellite and enargite was systematically investigated. Micro-flotation tests and contact angle measurements indicated that the addition of NaClO and FeCl3 increased the hydrophobicity difference between covellite and enargite. The bench-scale flotation test results show that the bulk copper concentrate could be separated into two products: a low-arsenic-containing (0.46%) and a high-arsenic-containing (5.18%) copper concentrate. X-ray photoelectron spectroscopy and scanning electron microscopy revealed that the oxidization treatment of NaClO caused the accumulation of oxides on the covellite surface, but not on the enargite surface. The varying precipitation of ferric hydroxide on the surfaces of covellite and enargite further exacerbated the difference in the hydrophilicity of these minerals. Thus, a possible method for separating enargite from covellite was obtained through oxidation treatment using NaClO and FeCl3.