Impact of Cellulases Treatment on Pulp Surface and Chemical Composition

Reducing energy consumption in the papermaking process is a critical challenge for the paper industry. One method to decrease energy usage in the refining process is the enzymatic pretreatment of pulp. Two different enzymes applied as pure cellulases (Celluclast® 1.5) and mixtures of cellulase and xylanase (Viscoflow® MG). Different dose of enzymes as 1.0, 2.0 and 4.0 IU were added to treat hardwood bleached kraft pulp at 50℃ for 60 minutes. SEM analysis confirmed fibrillation on the fiber surfaces of both cellulase-treated and mixed enzyme-treated pulps, indicating external fibrillation effects, which were more pronounced with cellulase. Compositial analysis of polysaccharides by 1H-NMR analysis showed that the mixed enzyme-treated pulp had reduced xylan content. which led less glucuronic acid content in pulp after enzyme hydrolysis. Cellulase only containing enzyme was more effective than cellulase and xylan mixture or water retention value increase as 51% up vs 41% up. Cellulase only enzyme was more effective than cellulase and xylanase mixture in enhancing fiber fibrillation, which led to more water retention.