Valorization of humins-extracted 5-Methoxymethylfurfural: towards high added value furanics via continuous flow catalytic hydrogenation

The formation of humins is one drawback of biomass valorization (e.g. hemicellulosic fraction) towards platform chemicals and fuels. Furanic compounds including 5 hydroxymethylfurfural and 5-methoxymethylfurfural can be extracted from humins and valorized. Unlike HMF, reactions with MMF have not been widely studied. In this work, 5-methoxymethylfurfural (MMF) was extracted from humins aiming to its hydrogenation in continuous flow. Based on success from literature studies with HMF hydrogenation, 5% Ru/C and 5% Pd/C catalysts were employed and both have demonstrated excellent conversion of MMF towards hydrogenation products (100%), with an interesting selectivity switch depending on reaction conditions. Ru-based catalyst were more prone to deactivation as compared to Pd catalysts, extremely stable after a few hours on stream under the investigated reaction conditions. A reaction mechanism was proposed for MMF hydrogenation.