Eco-friendly copper recovery process from waste printed circuit boards using Fe3+/Fe2+ redox system

- We developed an ecofriendly mediated electrochemical process for copper recovery.
- The recovery of copper was achieved without mechanical pretreatment of the samples.
- We identified the optimal flow rate for the leaching and electrowinning of copper.
- The copper content of the obtained cathodic deposits was over 99.9%.

The present study aimed at developing an original and environmentally friendly process for the recovery of copper from waste printed circuit boards (WPCBs) by chemical dissolution with Fe3+ combined with the simultaneous electrowinning of copper and oxidant regeneration. The recovery of copper was achieved in an original set-up consisting of a three chamber electrochemical reactor (ER) connected in series with a chemical reactor (CR) equipped with a perforated rotating drum. Several experiments were performed in order to identify the optimal flow rate for the dissolution of copper in the CR and to ensure the lowest energy consumption for copper electrodeposition in the ER. The optimal hydrodynamic conditions were provided at 400 mL/min, leading to the 75% dissolution of metals and to a low specific energy consumption of 1.59 kW h/kg Cu for the electrodeposition process. In most experiments, the copper content of the obtained cathodic deposits was over 99.9%.