PRELIMINARY STUDY ON TCF BLEACHING MECHANISM OF EUCALYPTUS KRAFT PULP

摘要

The bleaching agents of oxygen (O_2), hydrogen peroxide (H_2O_2), peracetic acid (Pa), and xylanase (X) were investigated in short-sequence TCF bleaching process. The results indicated that Eucalyptus kraft pulp could be bleached to high brightness(>81.1% ISO) and high viscosity (>800 ml/g) with a favoring strength properties by OPaP, OXPaP, O(Pa/P), OX(Pa/P) TCF bleaching sequences. The infrared spectra showed conjugated and non-conjugated carbonyl groups were destroyed and some auxochromes decreased by bleaching agent, which was the main reason of brightness increment.