含不同纤维素酶量的木聚糖酶对麦草浆性质的影响

Effect of Cellulase Contained in Xylanase on Wheat Straw Pulp Enzyme-Aid Bleaching

选用了里氏木霉的含不同纤维素酶量的木聚糖酶对麦草浆进行漂前预处理 ,研究了木聚糖酶中含不同纤维素酶量对浆料性能、结晶度和形态结构的影响。结果表明 ,随着用于预处理的木聚糖酶中纤维素酶量的增加 ,浆料的结晶度下降 ,浆料表面和横断面的孔隙增多 ,在相同氯用量时漂白浆白度逐渐上升 ,裂断长和耐破指数逐渐下降。当木聚糖酶活与CMC酶活的比值大于 1 2 1时 ,浆料的裂断长和耐破指数大于原浆。因此 ,木聚糖酶中少量纤维素酶的存在对提高漂白浆的白度有促进作用 。

Xylanases are commonly used to enhance the bleaching of pulp. Xylanases often contain a small amount of cellulase. Xylanases with different cellulase contents were used to pretreat wheat straw pulp before bleaching. The effects of xylanases with different cellulase contents on the pulp properties, cellulose crystallinity and fiber morphology of wheat straw pulp were investigated. The results indicated that the crystallinity of the pulp decreased and the pores in the surfaces and across sections of the pulp fibers increased with the increase of cellulase content in the xylanases used, and the bleached pulp brightness increased, the breaking length and bursting index decreased. When the ratio of xylanase to cellulase was higher than 121, the breaking length and bursting index of bleached pulp were higher than that of control pulp. Therefore, the presence of a small amount of cellulase contributed to the improvement of pulp brightness when the pulp was pretreated with xylanase before bleaching. But higher contents of cellulase caused damage to strength and crystallinity of the pulp.