Recovery of Copper from Waste Printed Circuit Boards by High-temperature Milling Process

Waste PCBs contain a large amount of valuable resources, including copper, and technology to recover them is constantly being developed.Generally, to recycle waste PCBs, a physical pretreatment process such as shredding and crushing is required.However, during this stage, the loss rate of metals is high and the sorting efficiency is low, indicating a need for a more efficient recycling pretreatment process.In this study, a high-temperature milling process, which simultaneously employs heat treatment and ball milling, was utilized to efficiently recover copper from waste PCBs.An experiment was conducted at 350 C with milling time, milling speed, and the weight of the balls as variables.The results showed a copper recovery rate of over 90% under the conditions of a ball weight of 500 g, a milling speed of 70 RPM, and a milling time of 5 hours.The purity of the recovered copper was approximately 93%, and through post-processing after the high-temperature milling process, the feasibility of reusing the recovered copper as a high-purity material was confirmed.