Selective Recycling of Cu Alloys from Metal-Rich Particles of Crushed Waste Printed Circuit Boards by High-Temperature Centrifugation

High-temperature centrifugation is an efficient and environmentally friendly method for separating and recycling comminuted waste printed circuit boards (WPCBs). In this research, it was used to recover copper (Cu) from metal-rich particles of WPCBs. Two steps separation process were conducted, and two alloys (Sn-Cu and Cu-Zn) were obtained at different temperatures. The results indicate that temperature has a great influence on the composition of Cu alloy, while the gravity coefficient only affects the recovery rate. At an optimized temperature of 1300 degrees C and a gravity coefficient of 1000, the total recovery values of Cu, Zn, Pb, and Sn were 98.84%, 86.96%, 98.33%, and 92.62%, respectively. By a combination of appropriate hydrometallurgical process and centrifugal separation of metals, this clean and efficient technology achieved a new way of recycling valuable metals from PCBs and effectively preventing environmental pollution of WPCBs.