A multifunctional co-solvent pair reveals molecular principles of biomass deconstruction

The complex structure of plant cell walls resists chemical or biological degradation, challenging the breakdown of lignocellulosic biomass into renewable chemical precursors that could support future production of green chemicals and transportation fuels. Here, experimental and computational results reveal how molecular interactions between tetrahydrofuran (THF)-water and lignocellulose can identify this co-solvent pair and other co-solvents as being multifunctional or capable of synergizing multiple key mechanisms driving the breakdown of biomass into valuable chemical precursors. Molecular simulations reveal that lignin globules expand in THF-water, an excellent “theta” solvent, dissociating both from themselves and from cellulose. The expansion of the lignin molecules in THF-water further exposes inter-unit linkages, rendering them susceptible to acid-catalyzed fragmentation by cleavage of aryl-ether bonds. Nanoscale infrared sensors confirm co-solvent mediated molecular rearrangement of lignin in the ...