Calculation of Distribution Coefficients of Cobalt and Copper in Matte and Slag Phases in Reduction–Vulcanization Process of Copper Converter Slag

Abstract

Copper and cobalt are two of the most valuable metals that can be recovered from copper converter slag. In the reduction–vulcanization process, copper is reduced before cobalt, while FeS vulcanizes Cu₂O into Cu₂S and forms the matte phase. The matte phase can dissolve the reduced metals as solvent. In this study, the distribution coefficient of cobalt between metallic cobalt in matte and CoO in slag, namely L _Co, was calculated to be 5000–8500 at the reaction temperature of 1600–1700 K, while the distribution coefficient between CoS and CoO, namely $L_{\text{Co}}^{{^{\prime } }}$, was calculated to be between 6 and 8. The distribution coefficient of copper between metallic copper in matte and Cu₂O in slag, namely L _Cu, was calculated to be in the range of 7500–8500, while the coefficient between Cu₂S and Cu₂O, namely $L_{\text{Cu}}^{{^{\prime } }}$, was calculated to be in the range of 60,000–75,000.