(669a) Subcritical CO2-Assisted Autohydrolysis for the Co-Production of Oligosaccharides and Fermentable Sugar from Corn Straw

Subcritical CO₂-assisted autohydrolysis pretreatment for oligosaccharides and fermentable sugars production from corn straw was investigated. The result showed that the prehydrolysate was rich in xylose, and about 90.22% were existed in the form of xylo-oligosaccharides (XOS), as well as the functional XOS (DP＜5) took up about 40%. Few inhibitors were formed during the pretreatment and almost no effect on subsequent fermentation. Additionally, the highest glucose yield was 90.59% (32.84g/100g corn straws) and 89.44% (21.17g/100g corn straws) of lignin was recovered in the enzymatic hydrolysis residue, it can be concluded that the proposed pretreatment method was an effectively way to improve corn straw enzymatic hydrolysis with few lignin degradation. Furthermore, the characterization data were also obtained through the analysis of pretreated solids at 170°C, 5Mpa CO₂ and 40min residence time using HSQC, XRD, FTIR, SEM and TG analyses.