Efficient Cleavage of Lignin-Carbohydrate Complexes and Ultrafast Extraction of Lignin Oligomers from Wood Biomass by Microwave-Assisted Treatment with Deep Eutectic Solvent.

ABSTRACT: Lignocellulosic biomass is an abundant and renewable resource for the production of biobased value-added fuels, chemicals, and materials, but its effective exploitation by an energy-efficient and environmentally friendly strategy remains a challenge. Herein, a facile approach for efficiently cleaving lignin-carbohydrate complexes and ultrafast fractionation of components from wood by microwave-assisted treatment with deep eutectic solvent is reported. The solvent was composed of sustainable choline chloride and oxalic acid dihydrate, and showed a hydrogen-bond acidity of 1.31. Efficient fractionation of lignocellulose with the solvent was realized by heating at 80?°C under 800?W microwave irradiation for 3?min. The extracted lignin showed a low molecular weight of 913, a low polydispersity of 1.25, and consisted of lignin oligomers with high purity (ca. 96?%), and thus shows potential in downstream production of aromatic chemicals. The other dissolved matter mainly comprised glucose, xylose, and hydroxymethylfurfural. The undissolved material was cellulose with crystal?I structure and a crystallinity of approximately 75?%, which can be used for fabricating nanocellulose. Therefore, this work promotes an ultrafast lignin-first biorefinery approach while simultaneously keeping the undissolved cellulose available for further utilization. This work is expected to contribute to improving the economics of overall biorefining of lignocellulosic biomass.

SUBMITTER: Liu Y 

PROVIDER: S-EPMC5413814 | biostudies-literature | 2017 Apr

REPOSITORIES: biostudies-literature