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. 24, 1984
Filed:
Apr. 13, 1981
Robert C Eckert, King County, WA (US);
International Paper Company, New York, NY (US);
Abstract
A process and solution for delignifying and brightening lignocellulosic pulp. The solution comprises from about 0.1 to about 5% by weight, based on oven-dried pulp of a peroxide and about 0.5 to about 20 mole percent, based on the moles of peroxide, of a metal ion selected from the group consisting of tungsten, molybdenum, chromium, osmium and selenium. The preferred process of this invention comprises contacting a lignocellulosic pulp with about 0.5 to about 20 mole percent, based on moles of peroxide, of a metal ion selected from the group consisting of tungsten, molybdenum, chromium, osmium and selenium at a temperature below about 50.degree. C.; adjusting the pH of the resultant pulp slurry to between about 1 and about 7; adding 0.1 to about 5% by weight based on oven-dried pulp of peroxide and effecting pulp delignification and brightening at about 30.degree. C. to about 100.degree. C. until most of the peroxide has been consumed.