ELECTROLYSIS METHOD USING TWO-CHAMBER ION-EXCHANGE MEMBRANE SODIUM CHLORIDE ELECTROLYTIC CELL EQUIPPED WITH GAS DIFFUSION ELECTRODE

摘要

A method of electrolysis is provided in which salt concentration is reduced in a caustic soda aqueous solution produced in the two-chamber ion exchange membrane brine electrolytic cell which is divided, by means of an ion exchange membrane, into a cathode chamber equipped with a gas diffusion electrode as a cathode and an anode chamber equipped with an anode. The electrolysis is conducted while a differential pressure [a pressure obtained by subtracting an oxygen-containing gas pressure in the cathode gas chamber (measured by a manometer 18) or a gas pressure at an oxygen-containing gas inlet 14 from a liquid pressure in the anode chamber which is applied on the ion exchange membrane when the anode chamber is filled with brine (= brine height x brine density ÷ 2)] between the liquid pressure and the gas pressure in the cathode gas chamber of the two-chamber ion exchange membrane electrolytic cell 1 employing the gas diffusion electrode 7 is reduced.