FRACTIONATION OF LIGNOCELL-ULOSE IN 1-BUTYL-3-METHYLIMID-AZOLIUM CHLORIDE IONIC LIQUID

摘要

Lignocellulose materials are potentially valuable resources for transformation into biofuels and biobased products. However, the complicated structures make it difficult to fractionate, which limits its utilization and economical conversion into valueadded products. In this study, a new and feasible fractionation method was proposed based on entire dissolution of biomass materials in ionic liquid. After complete dissolution of milled wood in l-butyl3-methylimidazolium chloride, cellulose-rich residues were collected via pouring the wood/IL solution in reconstitution solvent (e.g., acetone/water, 9:1, v/v). Lignin was recovered by concentration and precipitation of supernatant in acidified distilled water. Hemicelluloses were isolated from celluloserich materials after treatment with 3% NaOH. The physicochemical structures of the obtained cellulose, lignin and hemicelluloses were characterized by Fourier transform infrared (FT-IR) and twodimensional nuclear magnetic resonance (2D NMR) as well as high performance anion exchange chromatography (HPAEC). In addition, mass balance was illustrated for the dissolution and fractionation process of bagasse.