【作者】 蒙启骏； 付时雨； 李兵云； 李新良；

【Author】 MENG Qi-jun;FU Shi-yu;LI Bing-yun;LI xin-liang;State Key Lab of Pulp and Paper Engineering,South China University of Technology;

【机构】 华南理工大学制浆造纸工程国家重点实验室；

【摘要】 聚木糖酶和酸（硫酸）水解两种方法处理纸浆,对其中己烯糖醛酸（HexA）含量变化、纸浆性质及后续单段H₂O₂漂白的影响进行了研究。结果表明,聚木糖酶（50 IU/g,相对绝干纸浆）预处理可以降低纸浆中约15%的HexA含量,而采用酸水解（稀H₂SO₄,条件:pH=3,95℃,3 h）可以除去纸浆中60%的HexA,纸浆卡伯值快速降低,白度提高,但黏度损失严重。经单段H₂O₂漂白之后,聚木糖酶和酸水解预处理对漂白浆白度的提高效果不大,与未处理浆相比,白度分别仅提高1.3%和0.5%,但返黄值分别降低15%和11.7%,即白度稳定性得到改善。在H₂O₂漂白过程中,HexA含量无明显变化,仅减少4.0⁸.5μmol/g绝干浆。与未处理浆相比,经预处理漂白浆的物理强度均有所下降。更多还原

【Abstract】 The effect of hexenuronic acidon single peroxide bleaching of eucalyptus kraft pulp was investigated using both xylanase treatment and sulfuric acid hydrolysis.The HexA content after treating with xylanase of 50 IU/g was reduced by 15%.In comparison with the xylanase treatment,the acid hydrolysis under pH=3,95℃ and 3 h removed 60%HexA and decreased more the kappa number,but it resulted in lower viscosity.After subsequent QP bleaching,both xylanase and acid pretreatment brought about limited improvement on brightness.Compared to the control,enzyme and acid treatment can increase the brightness by only 1.3 and 0.5%,respectively.However,the brightness stability was improved remarkably by xylanase treatment and acid hydrolysis and the P.C.number was decreased by 15%and 11.7%,respectively.During QP bleaching,pulps only showed a slight decrease of HexA content about 4.0~8.5 μmol/g oven-dried pulp.The physical strength of bleached pulps with two pretreatment were somewhat inferior to the same properties measure in control pulps.更多还原