Simulation and economic analysis of a hydrometallurgical approach developed for the treatment of waste printed circuit boards (WPCB)

This paper presents the main achievements of a hydrometallurgical process to recover base and precious metals from waste printed circuit boards (WPCB). The technology comprises a first leaching process performed in a two-step counter current way with sulfuric acid and hydrogen peroxide for base metals solubilization and a consecutive cross leaching process with thiourea, ferric sulfate and sulfuric acid to extract precious metals. Furthermore, the reach solutions are subjected to cementation procedure with zinc powder to recover the elements of interests as metal powders. The spent solution achieved after cementation of precious metals is partially recycled within the process and the other part is treated by Fenton process and then neutralized with lime. Considering the achieved results at the laboratory level, the entire procedure was simulated using SuperPro Designer software to determine the process economy for an industrial plant. Besides this, the use of this software allows achieving the material balance of a process and the design of the plant. As a result, the process implementation at a larger scale is simulated and the main issues that can result in such a case can be determined and solved.