The Effect of Sulfur and Reduction Temperature on Cobalt Dissolution During Sulfuric Acid Leaching of Metallic Matte

Abstract

Abstract In this work, the influence of sulfur content and distribution on the efficiency of cobalt dissolution during H 2 SO 4 leaching of metallic matte (Fe-Co-Cu 2 S.FeS) has been investigated. The matte was formed by carbothermal reduction of copper slags containing 0.4% Co at temperatures between 1400–1800 °C in a submerged type DC arc furnace operated at 40–70 kVA. The sulfur content of the metallic matte varied from 1.32% to 3.10% depending on the reduction temperatures. Low temperature carbothermal reduction (1400–1450 °C) produced homogeneous sulfur distribution which enhanced the dissolution of cobalt from matte granules obtained by atomizing. Granules having a sulfur content between 2.9–3.1 % exhibited faulted structures. It was found that faulted structure having sulfur content higher than 2.9% was favoured cobalt dissolution.