| 摘要 |
1,051,597. Electrolytic production of chlorine and caustic soda. TEIJIN Ltd. Aug.21, 1963 [Aug.24, 1962], No.33136/63. Heading C7B. In the production of caustic soda and chlorine by electrolysis of aqueous sodium chloride solution in a cell divided by an anion-permselective membrane into anode and cathode compartments, the catholyte consisting of aqueous sodium chloride solution purified to remove electrolytically harmful materials such as magnesium ions and the anolyte consisting of a concentrated metal chloride solution, both catholyte and anolyte are continuously passed through the respective electrode compartments and the anolyte is recirculated and maintained of constant composition by removal of excess water e.g. by evaporation, and addition of metal chloride, e.g. as solid salt, externally of the cell. The anolyte salt may be sodium, aluminium or ferric chloride. In order to protect the anionic membrane from the evolved chlorine a porous non- ionic diaphragm, e.g. of pvc cloth, may be disposed between anode and anionic membrane. The process may be applied to a falling film mercury cathode cell or a diaphragm type brine cell using a perforates iron cathode and is used for electrolysing purified sea water typically having a chlorine concentration equivalent to 30 g/1 Na Cl. The cathode compartment may divided by a non-ionic e. g. pvc cloth, diaphragm in the same way as the anode compartment. In cells with divided electrode compartments the electrolyte is supplied to the portion adjacent the anionic membrane. |
