EFFECT OF LACCASE PRETREATMENT ON HYDROGEN PEROXIDE BLEACHING OF BAMBOO SCMP

摘要

The effect of laccase pretreatment on hydrogen peroxide bleaching of bamboo SCMP was discussed. The change of fiber surface after laccase pretreatment was analyzed by X-ray photoelectron spectroscopy (XPS). The results revealed that laccase pretreatment could improve the bleachability and brightness stability of SCMP. The optimal laccase pretreatment conditions were laccase 5IU/g, HBT 0.5%, oxygen pressure 0.2MPa, pH 6 and temperature 50°C. Under these conditions the brightness and PC number of pulp bleached by H2O2 were 60%ISO and 2.03. The analysis of XPS showed that 91.19% of pulp fiber surface was covered with lignin after laccase treatment, but before the treatment only 55.58% of fiber surface was covered. Lignin precipitated on the fiber surface after laccase treatment could be easily removed in H2O2 bleaching.