The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 23, 1993
Filed:
Oct. 04, 1991
Tatsuo Hiyoshi, Yokohama, JP;
Akio Kashiwada, Yokohama, JP;
Asahi Kasei Kogyo Kabushiki Kaisha, Osaka, JP;
Abstract
A method for the electrolysis of an alkali metal chloride in an electrolytic cell is disclosed, in which use is made of a cation exchange membrane comprising a carboxylate-containing fluorocarbon polymer layer disposed on a cathode compartment side and provided on its surface with an inorganic coating, and a sulfonate and/or carboxylate-containing fluorocarbon polymer layer disposed on an anode compartment side and having a water content of from 3 to 10% by weight. By this method, an alkali metal hydroxide, e.g., sodium hydroxide, can be directly produced in a concentration as high as 45-55 % by weight from a saline solution having an alkali metal chloride concentration as low as from 3.0 to 3.5N with reduced energy consumption, stably for a prolonged period of time.