Flow-through reductive catalytic fractionation of beech wood sawdust

The implementation of flow-through (FT) systems in the lignin-first approach can be a strategic tool for increasing the proficiency of biorefineries. Herein, the reductive catalytic fractionation (RCF) of waste beech wood sawdust (BWS) was conducted in an FT system using Ni on a nitrogen-doped carbon catalyst (35Ni/NDC) in pellet shape and MeOH and MeTHF as solvents. Lignin extraction was maximized in the first 4 h of time on stream (TOS), yielding maximum cumulative monomers of 247 mg gKL−1 using MeOH as solvent, extraction temperature of 235 °C, and reduction temperature of 225 °C. Importantly, the catalyst was used for two cycles and total time on stream (TOS) of 14 h without losing initial activity. These findings show that FT systems represent a promising solution for applications in lignin-first biorefineries.