Electrochemical dissolution of smelted low-grade electronic scraps in acid sulfate-chloride solutions

• Analysis of smelted WEEE was presented.
• Anodic dissolution of the alloy in H2SO4-Cl solutions was carried out.
• Composition of the slimes and deposits was discussed.
• Energy consumption was calculated.
• Optimal conditions for selective bronze recovery were defined.

The paper reports hydrometallurgical method for recovery of bronze (80–92% Cu) from smelted low-grade waste electronic parts. Detailed analysis of five phases in Cu–Zn–Sn–Ag–Pb alloy was presented. Anodic dissolution of the alloy in acid sulfate and sulfate-chloride solutions resulted in distinct metal separation with copper and tin codeposited on the cathode, lead and silver accumulation in the slimes, while zinc, iron and nickel were transferred to the electrolyte. Phase and chemical analyses of slimes and cathodic deposits were performed. The most favorable conditions for the alloy dissolution were obtained in 2 M H2SO4 with 0.1 M NaCl at the temperature of 60 °C, where the highest anodic current efficiency and the lowest energy consumption were found. At lower temperatures periodical inhibition of the alloy dissolution was observed in sulfate-chloride solutions.