Biological Bleaching of Chemical Pulps
- 1 January 2004
- journal article
- review article
- Published by Informa UK Limited in Critical Reviews in Biotechnology
- Vol. 24 (1), 1-58
- https://doi.org/10.1080/07388550490465817
Abstract
Use of biotechnology in pulp bleaching has attracted considerable attention and achieved interesting results in recent years. Enzymes of the hemicellulolytic type, particularly xylan-attacking enzymes, xylanases are now used commercially in the mills for pulp treatment and subsequent incorporation into bleach sequences. The aims of the enzymatic treatment depend on the actual mill conditions and may be related to environmental demands, reduction of chemical costs or maintenance or even improvement of product quality. The use of oxidative enzymes from white-rot fungi, that can directly attack lignin, is a second-generation approach, which could produce larger chemical savings than xylanase but has not yet been developed to the full scale. It is being studied in several laboratories in Canada, Japan, the U.S.A. and Europe. Certain white-rot fungi can delignify kraft pulps increasing their brightness and their responsiveness to brightening with chemicals. The fungal treatments are too slow but the enzyme manganese peroxidase and laccase can also delignify pulps and enzymatic processes are likely to be easier to optimize and apply than the fungal treatments. Development work on laccase and manganese peroxidase continues. This article presents an overview of developments in the application of hemicellulase enzymes, lignin-oxidizing enzymes and white-rot fungi in bleaching of chemical pulps. The basic enzymology involved and the present knowledge of the mechanisms of the action of enzymes as well as the practical results and advantages obtained on the laboratory and industrial scale are discussed.Keywords
This publication has 116 references indexed in Scilit:
- Effects of xylanase treatment on fibre morphology in totally chlorine free bleaching (TCF) of Eucalyptus pulpProcess Biochemistry, 2000
- Effect of Xylanase and Dosage on the Refining Properties of Unbleached Softwood Kraft PulpJournal of Wood Chemistry and Technology, 1999
- The Leachability of Lignin from Kraft Pulps after Xylanase TreatmentHolzforschung, 1994
- Biobleaching of kraft pulpProcess Biochemistry, 1992
- Oxidative degradation of high molecular weight chlorolignin by manganese peroxidase of Phanerochaete chrysosporiumBiochemical and Biophysical Research Communications, 1991
- In vitro depolymerization of lignin by manganese peroxidase of Phanerochaete chrysosporiumBiochemical and Biophysical Research Communications, 1991
- On the reactions of lignin peroxidase Compound III (isozyme H8)Biochemical and Biophysical Research Communications, 1989
- Effects of melecular oxygen on lignin degradation by Phanerochaete chrysosporiumBiochemical and Biophysical Research Communications, 1981
- Partial delignification of unbleached kraft pulp with ligninolytic fungiBiotechnology Letters, 1979
- Pleiotropic mutants of the wood-rotting fungus Polyporus adustus lacking cellulase, mannanase, and xylanaseCanadian Journal of Microbiology, 1974