Kinetics of SO2–ethanol–water (AVAP®) fractionation of sugarcane straw

•Sugarcane straw is efficiently fractionated by SO2–ethanol–water (AVAP®) technology.•Kinetics of straw AVAP® fractionation is largely similar to that of wood species.•Residual components and cellulose DP in pulp can be adjusted by changing conditions. Kinetics of SO2–ethanol–water (AVAP®) fractionation was determined for sugarcane (SC) straw in terms of pulp composition (non-carbohydrate components, cellulose, hemicelluloses) and properties (kappa number, pulp intrinsic viscosity in CED and cellulose degree of polymerization). Effect of temperature (135–165°C) and time (18–118min) was studied at fixed liquor composition (SO2/ethanol/water=12:22.5:65.5, w/w) and a liquor-to-solid ratio (4Lkg−1). Interpretation is given in terms of major fractionation reactions, removal of non-carbohydrate components and xylan, as well as acid hydrolysis of cellulose, and is compared to other lignocellulosic substrates (beech, spruce and wheat straw). Overall, SO2–ethanol–water process efficiently fractionates SC straw by separating cellulose from both non-carbohydrate components and xylan while reducing cellulose DP.