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:
Jan. 21, 1992
Filed:
Apr. 05, 1990
Applicant:
Inventor:
Gilles Dorris, Laval, CA;
Assignee:
Pulp and Paper Research Institute of Canada, Pointe Claire, CA;
Attorney:
Primary Examiner:
Int. Cl.
CPC ...
D21C / ; D21C / ;
U.S. Cl.
CPC ...
162 3011 ; 162 38 ; 162 82 ;
Abstract
Sodium sulfide or hydrosulfide is oxidized to produce sodium polysulfide and sodium hydroxide. Under appropriate conditions, the oxidation may be pursued further to convert all the sodium sulfide into sodium thiosulfate. The oxidation is carried out at or above atmospheric pressure in a mixed reactor or in a pipeline reactor, by sparging oxygen or air, in a mixture of white liquor and lime mud particles produced in the recausticizing plant of a kraft mill.