Treatment of Waste Copper Electrolytes U

The use of copper anodes with non-standard content of impurities for the treatment of waste sulfuric acid solutions, resulting from the industrial process of electrolytic copper refining, was investigated. These solutions contained high levels of copper, nickel, and arsenic, which necessitated the preparation of copper anodes with elevated concentrations of Ni, Pb, Sn, and Sb. This study aimed to examine the effect of high impurity content, along with the influence of solution temperature, on the behavior of the anodes during the electrolytic process simulating industrial conditions. The obtained results clearly indicate that the tested anodes are viable for use in the electrorefining process, as the dissolution of copper anodes continued without interruption despite the first appearance of passivation for A1 and A2 anodes; passivation for A3 anode was not detected during a test duration of 72 hours. The initial occurrence of passivation was detected earlier for the anode with the highest impurity content (A1) and at elevated temperatures. Throughout the electrolysis, the change in chemical composition of the electrolyte was monitored, revealing an increase in nickel concentration corresponding to the anode composition, while copper and arsenic concentrations decreased, with arsenic transferring into the anode slime.