Study on comprehensive utilization of wheat straw-XOS, pulp and energy

Pre-extraction of hemicellulose from wheat straw using alkaline cooking process was performed while the extract was enzymatic hydrolyzed and decolorized, and then the residual material after pre-extraction was cooked subsequently by soda pulping process. After that, the yield and characteristics of xylo-oligosaccharides (XOS) were analyzed, and the properties of the pulp and black liquor were also determined. The results indicate that the optimal dosage of alkali in the pre-extraction stage is 6%, the yield of XOS reaches to 40.45kg/t, and the degree of polymerization (DP) of XOS is 2.32. The yield of the subsequent soda pulp with lower NaOH charge is 378.1kg/t, its Kappa number and viscosity are similar to the control pulp, brightness, breaking length, tear index and folding endurance are higher than those of control. The viscosity of the black liquor is lower, and its gross calorific value is higher than that of control, over 15MJ/kg.