| 摘要 |
PURPOSE:To precipitate and to recover metallic copper of high grade, by conducting electrolysis while controlling the sum of concentrations of cuprous and cupric ions in the cathodic chamber of an electrolytic cell. CONSTITUTION:Copper chloride etching waste soln. is electrolyzed by maintaining the composition of the soln. in the cathodic chamber of an electrolytic cell at a sum of concentrations of cuprous and cupric ions, which are converted into theat of copper, not higher than 65g/l. The control of the copper ion concentration is performed by means of an absorbance meter using change in photopermeability of the cathodic chamber soln. The copper is precipitated and recovered as metallic copper by the following reactions, CuCl2 CuCl, CuCl Cu, etc. The soln. having been treated is circulated to the electrolytic cell. Hence, metallic copper contg. little Cl is continuously recovered at a high efficiency, thereby regenerating preferably the etching waste soln. |
