RECENT DEVELOPMENTS IN THE APPLICATION OF XYLANASE ENZYMES IN ELEMENTAL CHLORINE-FREE (ECF) AND TOTAL CHLORINE-FREE (TCF) BLEACHING

The use of biotechnology continues to attract increasing attention in pulp bleaching where there are no ic commercial applications of hemice llulolytic xylanase enzymes. A number of reasons are cited for using e nzymes in bleaching: environmental; economic; pulp quality; and flexib ility. Although environmental pressures on the pulp producers were res ponsible for the initial interest in new technologies or biochemical s olutions for eliminating chlorine-containing chemicals, and this is st ill perhaps the case in certain parts of the world, there is now a con sumer-led demand for ECF and TCF pulps. The production of these pulps offers opportunities to use enzymes, which provide a simple and cost-e ffective way to reduce the use of bleaching chemicals. Results of inte rnational experience with enzymes in ECF and TCF bleaching are shown a nd the contribution of enzymes to the economics of pulp bleaching are discussed.