Fractionation of Corn Stover By Non-Isothermal Flow-through (NIFT) Reaction

Corn stover was fractionated using a flow-through column reactor system for consecutive recovery of extractives and xylooligomer. During reaction, temperature was gradually increased and solubilized components were recovered in sample cylinders. In this process, hot-water was introduced into the biomass-packed column reactor; effective recovery of extractive including sucrose was achieved with low-temperature treatment around at 60-90°C, which was followed by the fractionation reaction at higher temperature (~210°C). Since temperature increased during reaction with various slopes, it is termed as non-isothermal flow-through (NIFT). Liquid hydrolyzate obtained from the early-stage of fractionation, which is rich in extractives, can be directly used for production of value-added products. Then, hemicellulose recovered in a form of xylooligomer can be recovered separately. The remaining solids after fractionation can be hydrolyzed by enzymes, and then fermented into liquid biofuels or bioproducts.

In this study, various treatment conditions (1) for effective fractionation of extractives and hemicellulose and (2) for effective pretreatment of remaining solids using non-isothermal flow-through reactor system were explored. Chemical compositions, enzymatic digestibility, and fermentability of treated samples will be reported in this paper.