Preparation of Ultrafine Copper Oxide Using Metal Powders Recovered from Waste Printed Circuit Boards

摘要

Waste printed circuit boards (WPCBs) have an inherent value because of nonferrous metal copper and noble metals. From the viewpoint of resource recycling and environmental protection, it is significant to recover metal materials from WPCBs. In this study, metal powders recovered from WPCBs were used to prepare ultrafine copper oxide powders using a microemulsion reaction. First, WPCBs were pretreated to obtain the metal powders with a copper content of 86.1% using a mechanical physical method. The leaching of the metal powders was carried out in a sulfuric acid solution by adding chloride and copper ions under aeration condition. By a solvent-extraction technology, copper ions in the leaching solution were extracted by N_(902) extractant and the raffinate was used to leach metal powders again. The loaded organic phase (N_(902) extractant) was stripped by an oxalic acid solution to form a microemulsion system. Ultrafine copper oxalate precipitations were produced in the microemulsion interfaces, and then calcined to form ultrafine copper oxide powders. X-ray diffraction and transmission electron microscopy results showed that the ultrafine copper oxide powders had an average size of approximately 100 nm.