Novel On-Site Cupric Oxide Recovery Process from Waste Containing Copper

Abstract

Although the copper-containing waste from semiconductor or printed circuit board (PCB) manufacturing contains a high concentration of copper, it is usually transported and treated outside of the factories. We studied a novel treatment technology for on-site recycling in the factories. In this technology, cupric oxide with a low-chloride-content was obtained from waste with a high copper concentration, such as cupric chloride etchant waste and cupric sulfate plating waste. In the proposed method, copper-containing waste mixed with H2O2 solution is added to NaOH solution by stepwise addition. In laboratory experiments, we optimized the reaction conditions and obtained low-chloride-content CuO from actual cupric chloride etchant waste and cupric sulfate plating waste. Based on the laboratory experiments, we constructed the first practical plant at a PCB factory and obtained low-chloride-content CuO.