Asahi Glass Company, Limited

Eiji Endo

Manabu Suhara

Yoshio Oda

A diaphragm electrolysis of an aqueous solution of sodium chloride is carried out by using a fluorinated cation exchange membrane which is made of a polymer having carboxylic acid groups as ion-exchange group and has 2.0 to 3.5 mole/Faraday of water permeability under the electrolysis.

Electrolysis of aqueous solution of sodium chloride

In a process for producing an alkali metal hydroxide which comprises electrolysis of an aqueous solution of an alkali metal chloride in an electrolytic cell having an anode compartment and a cathode compartment which are partitioned by a fluorinated cation exchange membrane, the improvement which comprises a fluorinated cation exchange membrane made of a fluorinated copolymer having carboxylic acid groups as the ion exchange group and having an ion exchange capacity of 0.5 to 2.0 meq/g dry polymer and a concentration of carboxylic acid groups of 8 to 30 meq/g water absorbed by the membrane when contacted with an aqueous solution of the alkali metal hydroxide having about the same concentration of alkali metal hydroxide as that of catholyte during said electrolysis.

Growing community of inventors

Yokohama, Japan

Eiji Endo