摘要 |
An electrolytic oxidation process for producing alkali metal permanganate form alkali metal manganate, and particularly for effecting such production to regenerate a permanganate working bath, such as used in desmearing, etch-back or cleaning processes in the manufacture of printed circuits, which has reached a level of decreased working efficiency, wherein an aqueous alkaline solution of manganate in alkali metal hydroxide (2) is electrolytically oxidized using a non-sacrificial anode (6) and a cathode (10) comprised of an alkali-resistant cathode electrode (12) immersed in a concentrated aqueous solution of sodium hydroxide (16) in a container (18) porous to ions which is formed from ion-porous polymeric membrane material. |