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:
Dec. 27, 1977
Filed:
Apr. 16, 1976
Applicant:
Inventors:
Assignee:
Asahi Glass Co., Ltd., Tokyo, JA;
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
B01D / ; C01D / ;
U.S. Cl.
CPC ...
23299 ; 2330 / ; 23303 ; 204 98 ; 423179 ; 423641 ;
Abstract
An aqueous solution of sodium hydroxide containing soluble impurities such as a concentrated catholyte produced by a diaphragm electrolysis is cooled by a coolant or a heat-exchanger to form a slurry containing sodium hydroxide hydrate crystals and fine impurity crystals. The fine impurity crystals are adsorbed on bubbles which are formed by vaporizing a dissolved coolant or introducing a gas in the slurry and separated from the slurry.