Precious Metal Recovery from Waste Electrical and Electronic Equipment through Oxidative Refining

Abstract

This study delves into the application of oxidative refining for the recovery and concentration of precious metals, namely palladium (Pd) and gold (Au), from waste electrical and electronic equipment by WEEE recycling, leveraging pyrometallurgical techniques. The primary objective is to optimize refining parameters, encompassing variations in gas pressure, temperature, and gas composition, to maximize the extraction and purification of precious metals from recycled materials. Through an array of comprehensive characterization techniques, encompassing microstructural analysis, elemental composition assessment, and metal concentration measurement, this study scrutinizes the potential of oxidative refining. The conclusive findings underscore the remarkable potential of oxidative refining in augmenting the efficiency and effectiveness of metal recovery from waste printed circuit boards (PCBs), with a pronounced emphasis on the concentration of Pd and Au. This research not only highlights the promise of oxidative refining but also concludes that optimizing process parameters, such as a N2/O2 mixed gas pressure of 4 L/min, a process time of 40 min, and a temperature of 1400 °C, is imperative for achieving the highest efficiency in metal recovery from electronic waste, especially precious metals like Pd and Au. It further contributes to the sustainable management of electronic waste and the strategic extraction of valuable precious metals.