Novel Solvent Systems for Biomass Fractionation Based on Hydrogen-Bond Interaction: A Minireview

Exploring more efficient solvent systems is important for biomass fractionation that can significantly boost the efficiency of biomass catalytic conversion. Ionic liquids (ILs) and deep eutectic solvents (DESs) as novel hydrogen bond based solvents have attracted more and more attention. Research shows that the hydrogen bond between solvents and biomass is the main factor for their excellent performance in biomass fractionation. The cation or anion of ILs can form strong hydrogen bonding with biomass components during the pretreatment processes, which weakens the hydrogen bond interactions between biomass components, and further promotes the destruction of the biomass hydrogen bond network. Similar to ILs, with their designed hydrogen bond donors and acceptors, DESs can also form strong hydrogen bonds with biomass components for fractionation. Herein, this review outlines the recent development of biomass fractionation research through hydrogen-bond interactions by using ILs and DESs with biomass. This work provides a framework for future investigation of biomass fractionation mechanisms, understanding the effect of ILs/DESs, and exploring more novel efficient biomass catalytic conversion systems.