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:
Aug. 20, 1991
Filed:
Apr. 26, 1989
Ragnar Bernhard, Falun, SE;
Stora Kopparbergs Berglags AB, Falun, SE;
Abstract
An aqueous solution containing sulphur dioxide and sodium in high percentages is obtained by bringing sulphur dioxide into contact with a recirculating aqueous solution of sodium hydroxide and previously absorbed sulphur dioxide to obtain a ratio between SO.sub.2 and the sum of SO.sub.2 and Na.sub.2 O of 0.61-0.66, preferably 0.63-0.65, and a concentration of SO.sub.2 and Na.sub.2 O amounting to 85-98%, preferably about 95% of the solubility maximum of the solution at the ratio and storage temperature in question. The invention also relates to a solution having the aforesaid ratio of SO.sub.2 /(SO.sub.2 +Na.sub.2 O) and concentation and its use for sulphite cooking purposes or for bleaching purposes.