Green and efficient utilization of beech sawdust waste for sorbitol production: Direct conversion residue via Ru2P/OMC derived from separated lignin

Abstract

This paper proposes a green and sustainable strategy to achieve efficient utilization of beech sawdust waste to produce sorbitol. First, ethanol dissolution method was used to extract lignin from sawdust. Subsequently, the lignin combined with phloroglucinol were used to fabricate ordered mesoporous carbon (OMC) using solvent evaporation induced self-assembly (EISA) method. Afterwards, Ru2P/OMC was synthesized and utilized as a catalyst for the production of sorbitol from the residue using pure water as green solvent. Finally, the yield of sorbitol and xylitol reached 77.2 % and 12.5 % at 200 °C in 5 h, respectively. Different characterization techniques were used to reveal the structural composition of the catalysts and the mechanism of the reaction. The results show that the bifunctional Ru2P/OMC catalyst has dual activity of hydrolysis and hydrogenation without sulfonation treatments. Interestingly, the bifunctional Ru2P/OMC catalyst has satisfactory activity, selectivity, and stability, which is promising in biomass waste conversion.