Synergism of mechanical activation and sulfurization to recover copper from waste printed circuit boards

Abstract

In the context of recycling metal to embrace the sustainability challenge, this work employs mechanochemistry to recover copper from waste printed circuit boards (WPCBs) for the first time. This work aims to recycle both copper (9.89 wt%) and resin, the two main components of WPCBs, to the largest extent. Copper and sulfur could be reacted to form copper sulfides by the aid of mechanochemistry in the model experiment, so the synergistic route of mechanical activation and sulfurization was proposed. After milling WPCB fragments and sulfur for 20 minutes and leaching as-milled sample in sulfuric acid (3 M) and hydrogen peroxide (30 wt%), the yield of copper reached nearly 90% and, also, resin was conserved for further utilization. This paper highlights the microstructural assessment of the synergism of mechanical activation and sulfurization. It is an alternative method for recycling a metal to transform it into a corresponding compound that exists in natural minerals, and mechanochemistry can help to fulfil this process in a green way.