Co-producing xylo-oligosaccharides, furfural, organic acids, and reducing sugars from rape straw through efficient dilute alkali-assisted hydrothermal treatment

Hydrothermal treatment is a clean and effectual treatment method. This work utilized the addition of organic acids and bases to assist the hydrothermal treatment of rape straw (RS), which eliminated the majority of lignin from the biomass. This enhancement of cellulose saccharification favored the conversion of hemicellulose into furfural and xylo-oligosaccharides. Pretreatment with 0.5 g/L NaOH at 200 degrees C for 1 h achieved 53.8 % lignin elimination rate and 63.7 % xylan removal rate. Additionally, the pretreatment liquor contained 1.1 g/L of furfural and 2.0 g/L of xylo-oligosaccharides. Various characterizations (FTIR, SEM, and XRD) and adsorption abilities of dye (Methylene Blue, Congo red, and Rose Bengal) were used to characterize the raw and pretreated RS, and the structure properties, chemical components and enzymatic saccharification efficiencies confirmed that the enhanced cellulose accessibility (from 372.2 mg/g to 712.1 mg/g), reduced lignin hydrophobicity (from 7.8 L/g to 2.9 L/g), and decreased lignin surface area (from 568.7 m2/g to 218.1 m2/g) had substantially promoted the enzymatic saccharification ability of RS. Dilute alkaline-assisted hydrothermal treatment method built in this work effectually improved the reducing sugar yield of RS, while co-producing furfural, xylooligosaccharides, organic acids, and reducing sugars opens new avenues for value-added utilization of strawbased biomass.