Effect of Xylanase Pretreatment of Wheat Straw on Its NaOH-AQ Pulping

Wheat straw was pretreated with xylanase to improve its pulpability.The effect of the xylanase pretreatment on NaOH-AQ cooking and the properties of the resultant pulp was studied in this paper.The result showed that the optimum conditions of pretreatment were pH value 4.5,pretreatment temperature 45℃,liquor ratio 1:6,pretreatment time 4 h,enzyme usage 20 IU/g.Compared with untreated wheat straw pulp,the pulp yield of the pretreated wheat straw with xylanase at the optimum conditions of pretreatment increased by 2.42 percentage points;the breaking length,bursting index and tearing index increased by 11.51%,10.99%,40.29% respectively;the brightness increased by 3.3 percentage points.