Selective Recovery of Copper from Waste Printed Circuit Boards by Ammoniacal Solvoleaching

This chapter delves into the selective recovery of copper from waste printed circuit boards (WPCBs) using an innovative hydrometallurgical process called ammoniacal solvoleaching. The study focuses on the use of LIX 84-I as an organic extractant, combined with a small amount of ammonia, to form copper-ammine complexes and simultaneously extract copper. Key topics include the optimization of leaching parameters such as stirring speed, LIX 84-I concentration, ammonia volume, temperature, and pulp density. The results show that under optimal conditions, a copper leaching yield of 68.6% can be achieved with minimal co-leaching of other metals. The chapter also explores the stripping of copper from the loaded organic solution using sulfuric acid, with stripping efficiencies reaching nearly 100% at concentrations of 3.0 M or higher. Furthermore, the recyclability of LIX 84-I is demonstrated over six cycles of leaching and stripping, highlighting the sustainability of the process. The conclusion emphasizes the high efficiency and selectivity of the ammoniacal solvoleaching process, making it a promising method for copper recovery from WPCBs.