High consistency cellulase treatment of hardwood prehydrolysis kraft based dissolving pulp

• A high pulp consistency condition favors the cellulase adsorption.
• The improvement in the pulp properties was enhanced under the high consistency cellulase treatment.
• The high pulp consistency concept has better industrial relevance.

For enzymatic treatment of dissolving pulp, there is a need to improve the process to facilitate its commercialization. For this purpose, the high consistency cellulase treatment was conducted based on the hypothesis that a high cellulose concentration would favor the interactions of cellulase and cellulose, thus improves the cellulase efficiency while decreasing the water usage. The results showed that compared with a low consistency of 3%, the high consistency of 20% led to 24% increases of cellulase adsorption ratio. As a result, the viscosity decrease and Fock reactivity increase at consistency of 20% were enhanced from 510 mL/g and 70.3% to 471 mL/g and 77.6%, respectively, compared with low consistency of 3% at 24 h. The results on other properties such as alpha cellulose, alkali solubility and molecular weight distribution also supported the conclusion that a high consistency of cellulase treatment was more effective than a low pulp consistency process.