| 摘要 |
PURPOSE:To regenerate a waste etching soln. consisting of a metallic chloride without generating harmful gaseous Cl by electrolytically reducing the metallic ions in the waste etching soln., depositing part thereof on a cathode and oxidizing the remaining metallic ions in succession thereof. CONSTITUTION:The waste etching soln. consisting of, for example, CuCl2 as a principle agent is fed from a waste liquid storage tank 1 to a cathode chamber 3 of an electrolytic cell 2 having a diaphragm 7 and the liquid D after the adjustment of specific gravity from a specific gravity adjusting cell 14 is supplied into an anode chamber 4. Electricity is conducted to electrodes 5, 6. Cu(II) in the waste liquid is electrolytically reduced to Cu(I) in the chamber 3 and Cu(I) is electrolytically oxidized to Cu(II) in the anode chamber 4. The catholyte B is fed to an electrolytic cell 10 to deposit Cu on the cathode 11. A decopperizing treatment is thus executed without generating the gaseous Cl. The liquid which is decreased in the specific gravity by such treatment is subjected to the specific gravity adjustment in the cell 14. The liquid D is then supplied into the anode chamber 4 of the cell 2 and is electrolytically oxidized. The oxidized liquid is stored as the regenerated etching soln. in a storage tank 16 and is reused for an etching treatment. |
