SANS Study of Cellulose Extracted from Switchgrass

Abstract

Abstract Lignocellulosic biomass, an abundant renewable natural resource, has the potential to play a major role in generation of renewable biofuels through its conversion to bio-ethanol. Unfortunately, it is a complex biological composite material that shows significant recalcitrance making it a cost-ineffective feedstock for bioethanol production. Small-angle neutron scattering (SANS) was employed to probe the multi-scale structure of cellulosic materials. Cellulose was extracted from milled native switchgrass and switchgrass that had undergone the dilute acid pretreatment method to disrupt the lignocellulose structure. The high-Q structural feature (Q > 0.07 Å-1) can be assigned to cellulose fibrils based on comparison with the switchgrass purified by solvent extraction of native and dilute acid pretreated and a commercial preparation of microcrystalline cellulose. Dilute acid pretreatment results in an increase in the smallest structural size, a decrease in the interconnectivity of the fibrils; and no change in the smooth domain boundaries at length scales larger than 1000 Å.