Mechanism and Clean Procedure to Extract Gold from Printed Circuit Board

The recoveries of gold from printed circuit board are carried out in this work. Chemical analysis of waste printed circuit board was determined by ICP (Inductively Coupled Plasma) method. The dissolving mechanism of gold was elaborate. The thermodynamics for leaching process of gold was analyzed, the E-pH diagrams at 298K were drew by Factsage software. The stability of leaching process of gold in thiourea solution was investigated, the optimal experimental conditions were obtained. Moreover, orthogonal experiments were carried out based on single factor experiments, the most important factor for the gold leaching process was the concentration of thiourea solution.