Biomass into chemicals: One-pot production of furan-based diols from carbohydrates via tandem reactions

In this work, the direct production of furan-based dials from carbohydrates and their upstream raw materials via one-pot tandem reactions in ionic liquid/water system is presented. In this novel reaction system, ionic liquid serves as an advantageous solvent for polysaccharide (cellulose, inulin, sucrose) hydrolysis and hexose dehydration reactions, and heterogeneous Pd, Pt, Ir, Ni, Ru-based catalysts catalyze HMF hydrogenation reaction under relatively mild condition (50 degrees C, 6 MPa H-2) to afford moderate to high yield (34.0-89.3%) of furan-based diols, namely, 2,5-dihydroxymethylfuran (DHMF) and 2,5-dihydroxymethyltetrahydrofuran (DHMTF). Our results show that the metal species strongly affects the selectivity of the products, while the nature of the support influences the activity of the catalysts significantly. By selecting the proper metal species and the support, controllable production of DHMF or DHMTF was realized. Based on the intermediates identified and the conversion results, the proposed reaction pathway, including possible side reactions were presented. Taken together, our catalytic system featured with simple process, mild condition, high yield of diols and adjustable product selectivity. The direct conversion of the carbohydrates and the upstream materials drives our technology nearer to real application for cost-efficient production of chemicals from biomass. (C) 2014 Elsevier B.V. All rights reserved.