Feedstock-agnostic reductive catalytic fractionation in alcohol and alcohol-water mixtures

Many biomass conversion technologies focus primarily on tailor-made processing conditions for a single feedstock, in contrast to developing a practical operational window for effective processing of a broad variety of lignocellulosic biomass substrates available year-round. Here, we demonstrate the feedstock flexibility of reductive catalytic fractionation (RCF), performed in both batch and flow-through (FT) modes, to effectively process a range of biomass types (hardwoods, softwoods, and herbaceous monocots), regardless of their macromolecular composition and morphological structure differences. Both batch and FT-RCF performed with pure methanol as a solvent allow delignification (or lignin oil yield) values and lignin monomer yields greater than 65 wt% and 25 wt%, respectively, and high retention of carbohydrates (>90%) from herbaceous monocots (corn stover and switchgrass) and hardwood (poplar) biomass substrates, despite the inherent differences between woody and herbaceous biomass feedstocks. FT-RCF of pine (softwood) exhibited lower lignin extraction efficiency (