Recent advances in recovering technology for recycling gold from waste printed circuit boards: a review

Abstract

ABSTRACT With the rapid development of science and technology, the updating speed of electronic equipment is accelerated, massive electronic waste has been produced. According to statistics, about 53.8 million tons of e-waste were generated worldwide in 2019, which is expected to increase to 74 million tons by 2030. Printed circuit board (PCB) is the core component of electronic equipment. The surge of electronic waste leads to a large number of waste printed circuit boards (WPCBs). One ton of WPCBs contains about 80–1500 g of gold, and the concentration is 40–800 times that of gold in gold ore. Therefore, WPCBs have become a gold mine with great recycling potential. In recent years, more and more researchers have paid attention to the recovery of gold resources in WPCBs, which is of great significance to explore the economic potential of WPCBs. This review excludes smelter technology and summarizes the related processes of gold recovery from WPCBs from three aspects: physical technology, biological metallurgy and hydrometallurgy. Physical technology is environmentally friendly, biological metallurgy is more cost-effective and safe, hydrometallurgy makes up for the metal loss caused by traditional recovery technology, and has high applicability. Based on the existing technology, an environment-friendly and efficient process for gold recovery from WPCBs is proposed.