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:
Sep. 25, 1979
Filed:
Mar. 14, 1978
Applicant:
Inventors:
Assignee:
Nittetu Chemical Engineering Limited, Tokyo, JP;
Attorney:
Primary Examiner:
Assistant Examiner:
Int. Cl.
CPC ...
C01D / ;
U.S. Cl.
CPC ...
423203 ; 423204 ; 423641 ;
Abstract
A process for recovering caustic alkali from spent alkali liquor, in which a spent alkali liquor and iron oxide are roasted to obtain a product containing alkali ferrate and the product of roasting is hydrolyzed at a temperature over 110.degree. C. and under pressurized conditions where liquid phase is retained, thereby recovering caustic alkali in the form of an aqueous solution of a concentration higher than approximately 15 wt% containing dissolved iron in an extremely small concentration.