One-Step Conversion of Biomass-Derived 5-Hydroxymethylfurfural to 1,2,6-Hexanetriol Over Ni–Co–Al Mixed Oxide Catalysts Under Mild Conditions

The conversion of biomass-derived 5-hydroxymethylfurfural (HMF) was examined over Ni–Co–Al mixed oxide catalysts derived from corresponding hydrotalcite-like compounds (HTlcs). 1,2,6-Hexanetriol (1,2,6-HT) was obtained in 64.5% yield under mild reaction conditions. The catalysts were characterized by X-ray powder diffraction (XRD), CO2 temperature-programmed desorption (CO2–TPD), N2 physical adsorption, and H2 temperature-programmed reduction (H2–TPR), and the reaction product distribution was correlated with the catalyst composition and reaction conditions. The reaction pathway was proposed based on the results. In all cases, the conversion of HMF proceeds according to a pathway that begins with the aldehyde group being hydrogenated to form 2,5-dihydroxymethylfuran (2,5-DHF). This product then undergoes a ring-opening reaction to form 1,2,6-HT. A synergetic effect between Ni and Co was observed, which significantly promoted catalytic activity and selectivity.