2026 Gotovac Atlagic Ammonia Salt Leaching of Waste PCBs

The escalating accumulation of electronic waste (e-waste), currently estimated at approximately 45 million tons annually worldwide, poses significant environmental and resource recovery challenges. This research aims to recover copper from discarded printed circuit boards (PCBs) and convert it into copper oxide (CuO) nanoparticles. Mechanical separation methods were employed to remove polymeric layers from metal-rich components of PCBs, which were subsequently subjected to chemical extraction using ammonium-based salts. Results indicated that copper extraction efficiency improved when the polymer/ceramics fraction of PCBs was eliminated through grinding. The study specifically investigated PCB types designated as PCB3, revealing that leaching with ammonium citrate yielded optimal results. Additionally, copper oxide nanoparticles were characterized using techniques such as X-ray powder diffraction and scanning electron microscopy, confirming their structural integrity and potential for high technological applications, particularly in industrial organic synthesis. This work addresses both environmental sustainability by repurposing e-waste and economic factors by meeting the increasing demand for copper in a resource-constrained setting.