蔗渣化机浆过氧化物漂白及返黄的研究

本文的研究表明,白度为31.1％的蔗渣CMP原浆在H_2O_2消耗约4％时经单段或两段H_2O_2漂白后,白度分别达54.8％和75％;瀑白前后分别用EDTA、草酸等处理能有效地提高白度;H_2O_2总量不变时,提高第二段H_2O_2用量有利于浆料白度的提高。增加漂白段数能有效地减少漂浆返黄。与未漂浆相比,漂白浆的打浆度、成纸紧度、撕裂度和裂断长均有提高,不透明度下降。FI-IR显示用H_2O_2漂白蔗渣CMP浆有一定脱木素作用。

H2O2 Bleaching of Bagasse CMP

Conditions of H2O2 bleaching of Bagasse CMP, their effect on the brightness stability of the bleached pulp and the change of chromophore in bleaching and yellowing were investigated in present study.The results showed that brightness of the pulp could be raised from 31. 1% to 54. 8% and 75% at 4% H2O2 consumption after one bleaching stage and two bleaching stages respectively. Pulp pretreated with EOT A and added by ethene diacid after bleaching could increase brightness greatly. Increasing the H2O2 charge of the second stage would raise the brightness on condition that the total charge was unchanged. The results of yellowing of the bleached pulp indicated that adding stages of bleaching could reduce lightinduced and heat-induced yellowing. Using Na2S2O4 for final bleaching stage, its reduction could improve brightness stability of the pulp effectively. Compared with original pulp,the beating degree of bleached pulp was increased,density, tear factor, elongation at rupture of the sheet were reduced at some extent, and the opacity was decreased. Delignification effect was found in H2O2 bleaching by means of FI-IR.