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US 2004/0000380 A1Published application
Method for brightening pulp with hydrosulfite solution
AssigneeRohm and Haas Company
InventorRangamannar Goda
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Abstract
A method for brightening pulp at a pH from 4.5 to 9. The method comprises the steps of: (a) combining an alkali metal borohydride, an alkali metal hydroxide, an alkali metal bisulfite and phosphoric acid to form a reducing solution; and (b) adding the reducing solution to a pulp slurry in an amount from 0.1% to 4% of hydrosulfite based on dry pulp fiber.
Claims10
A method for brightening pulp at a pH from 4.5 to 9;
- said method comprising steps of:
- (a) combining an alkali metal borohydride, an alkali metal hydroxide, an alkali metal bisulfite and phosphoric acid to form a reducing solution;
- and
- (b) adding the reducing solution to a pulp slurry in an amount from 0.1% to 4% of hydrosulfite based on dry pulp fiber.
1 more element
Dependencies are inferred from the claim text.