EFFECTS OF ENDO-XYLANASE AND XYLOSIDASE PRETREATMENT ON BLEACHING PROPERTIES OF WHEAT STRAW PULP

Effects of endoxylanase and xylosidase pretreatment on bleaching properties of wheat straw pulp have been investigated.Results show that brightness of bleached pulp with endoxylanase and xylosidase pretreatment is increased respectively by 2.5 and 1.9 percentages greater than that of control pulp,and strength of bleached pulps is better than that of control pulp.Endoxylanase and xylosidase acted synergistically on the pretreated wheat straw pulp before its bleaching.Brightness of bleached pulp with mixture of endoxylanase and xylosidase is increased respectively by 0.9 and 1.5 percentages greater than that with endoxylanase and xylosidase pretreatment.It is found that there were many pores in the surfaces and across sections of pulp with endoxylanase and xylosidase under electronic microscope,and pores of pulp with endoxylanase pretreatment were more and larger than those with xylosidase pretreatment. It is found that endoxylanase and xylosidase could not destroy pulp crystallinity by Xray analysis.