Biphasic solvent systems enabled lignocellulosic biomass fractionation: A pathway towards comprehensive biomass utilization

Lignocellulosic biomass is mainly composed of cellulose, hemicellulose and lignin, which can be valorized into myriad fuels and chemicals. Most developed processes for its valorization focused on the utilization of only one or two components, incurring waste of resources and weakening the economic competitiveness. Fractionation of lignocellulosic biomass into individual components, viz. cellulose, hemicellulose, and lignin, facilitates their conversion and enables full biomass utilization. Pretreatment employing biphasic solvent systems represents a promising pathway for biomass fractionation. Here, we summarized the performance of different biphasic solvent systems for biomass fractionation, and factors governing their performance were discussed. The properties of fractionated streams and valorization potentials were reviewed, and strategies to tune properties were proposed. Finally, techno-economics of biphasic solvent systems enabled pretreatment were examined and future perspectives on improving their economic viability were provided. •Biphasic solvent systems enable clean biomass fractionation.•Cellulose, hemicellulose and lignin can be easily recovered with high yield.•Cellulose recovered in the solid phase shows high digestibility.•Lignin with appealing properties could be recovered in organic phase.•The economic viability of biphasic systems should be considered and improved.