Continuous electrolytic refining process of cathode copper with non-dissolving anode

Abstract

In traditional industrial production, cathode copper is co-prepared by both the pyrometallurgical process and wet electrolytic refining method. In this work, a non-dissolving electrode lead dioxide was used as an anode in an electrolysis experiment, and copper oxide was added to maintain the concentration of copper ions in the electrolyte to improve the quality of cathode copper and current efficiency in the electrolytic copper process. The method could avoid energy consumption in the pyrometallurgical process. The effect of three kinds of electrolytes on the macroscopic morphology, microstructure, current efficiency, purity, and crystal composition of the cathode copper was analyzed. In the electrolysis experiment, Cu2O and CuO phases were observed in the cathode copper by using electrolyte A for a long time. With the use of electrolyte B, the purity of the products did not meet the standard of the cathode copper. With the use of electrolyte C, the products prepared by electrolysis four times for 8 h or 2 h each time met the standards for morphology, current efficiency, and purity. The average current efficiency of electrolysis for 8 h was 96.33% with the new non-dissolved anode, which was 2.58% higher than that of the traditional dissolved anode. Moreover, the electrolyte can be recycled after use with the improved electrolyte and process. This new process can save energy and reduce material consumption for copper production in the hydrometallurgical industry. In addition, this paper provides a new method of improving the current efficiency and product quality in the electrolytic process of industrial production of metals.