Copper Electrorefining from Anodes with Non-Standard Content of Ni, Pb, Sb and Sn

Abstract

The use of copper use in electronics sets the electrorefining process as the basic method to produce this highly pure metal. Copper anodes with non-standard nickel, lead, antimony and thin content can be used for refining by the standard electrochemical process. The waste solution from the standard copper electrorefining process can be used as a working solution. In this way the two goals are reached, the effect of environmental protection through treating secondary materials and the commercial effect through obtaining usable metal. Beside copper, there is а high concentration of nickel and arsenic in this waste solution. The effect of nickel in maximum content of 10 mass %, the effect of lead, tin and antimony in maximum cumulative content of 3 mass %, as well as the effect of working solution temperature were investigated. Measured values of cells voltage have shown the appearance of three characteristic phases: stable phase, oscillation phase and full passivation phase, but during the 72 hours of each set of experimental conditions no full passivation of anodes was registered. The results of anode mass changing have revealed that the dissolution of anode is similar at two different operating temperatures. Mass balance for copper has shown that the copper cathode mass is higher than the mass of dissolved copper from the related anode. Based on data for chemical composition of working solution changing, it was pointed out that the copper concentration decreased during the process, maximum up to 1 g dm-3. The achieved recycling degree of waste materials has both environmental and economic effects, since the maintenance of cleaner environment and the utilization of sustainable resources indicate a socially responsible behavior.