THE MECHANISM OF XYLANASE TREATMENT ON ACIDIC HYDROGEN PEROXIDE BLEACHING OF SULFITE PULP

摘要

The mechanism of xylanase (X) treatment on the acidic hydrogen peroxide bleaching (i.e. POs) of magnesium sulfite bamboo/bagasse pulp was studied by X-ray diffraction analysis and FT-IR spectroscopy. Both of the ways can reflect the changes of cellulose crystallization structure of the sulfite pulp in POs bleaching and after X-POs treatment. The celluloses of the studying samples have the same lattice as cellulose-I. X-ray diffraction analysis shows that (002) peaks are sharper than (101) peaks and (101) peaks overlap (10 1 - ) peaks, which are in the form of round-blunt shape. IR spectroscopy analysis shows that conventional POs bleaching pulps and X-POs bleaching pulps are less crystalline than that of unbleached pulp. But X-POs bleaching pulps are more crystalline than POs bleaching pulps. The results indicate that X-POs bleaching is more effective in degrading the residual lignin and protecting carbohydrate than the conventional POs bleaching.