Chapter 7 - Enzymes: Applications in Pulp and Paper Industry

Abstract

The pulp and paper production technology is highly diverse and provides numerous opportunities for the application of microbial enzymes in processes, such as biopulping, biobleaching, de-inking, pitch removal, fiber grafting, paper coloration, and bioremediation of effluents. Although many applications of enzymes in pulp and paper industry are still at the research and development stage, currently the most important application is eco-friendly biobleaching of hard and soft wood pulps. In most instances, the enzymes employed are xylanases, laccases, and rarely mannanases, which offer the potential alternative to conventional, environmental-polluting chlorine and chlorine-based bleaching. Many industries all over the world are evaluating the potential of these biocatalysts through routine trials at large scale delignification of pulps. On the other hand, pitch control by lipases (and recently by laccases) has also being widely adapted by several paper mills as a quality-enhancing step. Improved pulp drainage with enzymes is practiced routinely at several mills. But before the complete implementation of enzymes in papermaking industries, there are some critical challenges, especially for laccases regarding their low redox potential and dependency on cost-intensive mediators.