Combined alkali impregnation and poly dimethyl diallyl ammonium chloride-assisted cellulase absorption for high-efficiency pretreatment of wheat straw

Abstract

Abstract Bio-enzyme pretreatment can effectively reduce the chemical resistance of wood fibers, thereby resulting in a reduction in energy consumption during the pulping process. However, both cellulase and cellulose fibers commonly exhibit negative charge used in water, leading to inherent electrostatic repulsion. The present study developed a novel combined pretreatment approach involving alkali impregnation and poly dimethyl diallyl ammonium chloride (PDADMAC)-assisted treatment to enhance the efficiency of cellulase treatment and obtain pulp with superior properties. The results showed that the alkali impregnation effectively destroyed the waxy layer on the surface of wheat straw, enhancing the interaction between subsequent cellulase and wheat straw fibers. The presence of PDADMAC further facilitated cellulase adsorption onto the wheat straw surface. When the PDADMAC dosage was increased to 1.0×10− 3 g/g wheat straw, the cellulase adsorption rate exhibited a significant increase of 42.28%. Additionally, at cellulase dosages of 10 U/g and 15 U/g, the pulp filtration capacity demonstrated improvements of 35.41% and 16.30%, respectively.