Efficient Recycling of Copper from Waste-Printed Circuit Boards via Suspension Electrolysis Using Response Surface Methodology

Abstract

Recycling of waste printed circuit boards (WPCBs) is an important subject not only for the protection of the environment, but also for the recovery of valuable materials, especially copper. In this paper, an effective and benign process for copper recovery from WPCBs is presented. In the process, copper in the WPCBs was treated through suspension electrolysis to gain copper powder. The effects of process parameters of H2SO4 and CuSO4 concentrations and the current density were studied. Experimental results showed that the suspension electrolysis process is an effective method to recover copper from WPCBs. The X-ray diffraction (XRD) and electronic differential system (EDS) spectra indicated no other impurities in the recycled copper. The copper recovery conditions were optimized using a Box-Behnken design of response surface methodology. The optimum conditions were observed when the solution contained 3 g/L CuSO4, 11 g/L H2SO4, and current density of 3 A/dm2, resulting in a recovery efficiency of 86.46%. The results indicate the process as a promising method to recover copper from WPCBs.