| 摘要 |
PURPOSE:To recover easily granular metallic copper which precipitates on the cathode side, by specifying the cathodic current density in electrolytic treatment of etching waste soln. CONSTITUTION:The electrolysis of copper chloride etching waste soln. is conducted in the range of a cathodic current density 20-150 A/dm<2>. The area of cathode of the electrolytic cell is maintained not larger than 1/2 of the area of the anode, and the increase in anodic current density is restrained against the increase in cathodic current density. Hereby, the copper precipitating on the cathodic side maintains granular shape and hardly adheres to the electrode as agglomerate, and is separated, precipitated and recovered easily. Consequently the electrolysis is performed continuously without exchanging electrodes, and the cupric chloride is recovered at a high efficiency. |
