BLEACHING PAPER PULP WITH HYDROGEN PEROXIDE IN AN ALKALINE MEDIUM IN WHICH ADDITIONAL ALKALI IS ADDED WHEN FROM 40-75 OF THE ORIGINAL QUANTITY OF PEROXIDE HAS BEEN CONSUMED

摘要

High-yield lignocellulosic wood pulps are bleached by treating same with an effective bleaching amount of hydrogen peroxide in an alkaline treatment medium, including adjusting the alkalinity of such pulp by adding a supplementary amount of alkaline agent thereto at that point in time when the amount of hydrogen peroxide consumed ranges from 40% to 75% of the effective amount thereof.