Precious metal recovery from electronic wastes based on electrochemistry

Abstract

In this work, the fabrication of electrode which selectively capture gold species in the matrix of different elements was showed. For that, the porous porphyrin polymer, COP-180, was used which has already been verified as an effective adsorbent for gold recovery from electronic waste. Even after the electrode was fabricated, COP-180 maintained its outstanding gold-capturing property (>1.4 g Au/g COP-180). Further, this study provides the electrochemical gold desorption system which uses the gold adsorbed electrode as an anode. The performance was remarkable with the high conductivity and current density of the electrode, achieved with >70% of desorption efficiency within 15 minutes. This gold dissolved solution was used as electroless nickel immersion solution to recover gold in the form of a film with >99% recovery yield. This study demonstrates the application of adsorbents as the metal capture electrode and electrochemical mediated process that achieves high feasibility for the sustainable recovery of metal resources from e-waste.