Enhancement of resource recovery from retired tires: Extraction of copper and zinc resources

Abstract

The disposal of scrap rubber, represented by retired tires, has achieved industrial achievements, but the handling of brass-coated steel wire as a structural reinforcement in retired tires has received little attention. A feasible and efficient method of acquiring economical resources is proposed to extract copper and zinc (Cu-Zn) from brass-coated steel wire. With 20% ammonia, 10% hydrogen peroxide, and a liquid-solid ratio of 10, the brass coating almost completely dissolved in 5 minutes. This technique may remedy the challenge of weak dissolving efficiency brought on by the dual phase microstructure of brass. Electrochemical measurements and density functional theory (DFT) simulations assist in verifying that hydrogen peroxide decreases the resistance of the corrosion and that OH- and O-2 in solution are the main contributors to the dissolution. In addition, the AH effectively enhances the corrosion of the α phase in brass, which is notably evident in comparable works. This effective strategy broadens the application of retired tires and provides a new method for extracting Cu-Zn resources.