A benign and effective process for
cuprous chloride synthesis and simultaneously recovery of Ag and Pd from waste printed circuit boards (
PCBs) was developed in the present study. The main merit of the process is that neither
corrosive acid nor strong
oxidant was used. The
PCBs were firstly pretreated by thermal
shock process to obtain metallic particles (MPs), then
cuprous chloride was synthesized by reacting MPs with
cupric sulfate in the presence of
sodium chloride. The optimum [Formula: see text] (mL/g) ratio, [Cu]/[Cu(2+)] mole ratio, treatment time and operation temperature were 6, 0.95, 30 min and 60°C, respectively. Approximately 98.5% of Cu could be recovered from the
PCBs through two synthesis circles. During the synthesis process, Ag and Pd could be simultaneously recovered by forming a stable
chloride complex since Cu(2+) played the role of
oxidant in the system. The recovery percentages of Ag and Pd were 93.9% and 95.3%, respectively. Accordingly, it is believed that the process developed in the current study is benign and practical for
copper and precious
metal (Ag, Pd) recovery from waste
PCBs.