KRAFT WOOD PULP TCF AND ECF BLEACHING WITH ENZYME PRETREATMENT *

Softwood kraft pulps were treated with a xylanase Irgazyme 40_X4. Various elemental chlorine free (ECF) and totally chlorine free (TCF) bleaching with or without enzyme pretreatment have been carried out. The results show that the enzyme pretreatment makes the downstream bleaching more effective, resulting in increase of brightness,decrease of Kappa number and improvement of pulp viscosity, and it may be capable of producing 88%ISO brightness pulp without using elemental chlorine.