Pretreatment Process of Polymetallic Complex Copper Anode Slime by Oxygen Pressure Acid Leaching

The removal of copper and nickel from complex copper anode slime by oxygen pressure acid leaching was studied. The effects of reaction temperature, sulfuric acid concentration, liquid-solid ratio, stirring speed, oxygen partial pressure and reaction time on the removal of copper and nickel were investigated. The results show that, at the following optimal conditions, including anode slime of 30.0 g, 1.5 mol / L sulfuric acid solution of 300 mL, liquid-solid ratio of 10 (mL:g), reaction temperature of 160 °C, oxygen partial pressure of 0.2 MPa, stirring speed of 600 rpm, and leaching time of 3 h, the leaching rates of Cu and Ni can reach 99.26% and 95.36%, respectively, while the leaching rates of Sb and Bi were only 1.33% and 0.59%，Sn was hardly leached.The leaching solution can be returned to the electrolytic purification system to recover Cu and Ni, and the enrichment of high-value metals (such as Sn, Sb, Bi and precious metals ) were nearly 2.7 times.