2,5-Dimethylfuran Production by Catalytic Hydrogenation of 5-Hydroxymethylfurfural Using Ni Supported on Al2O3-TiO2-ZrO2 Prepared by Sol-Gel Method: The Effect of Hydrogen Donors

5-Hydroxymethylfurfural (5-HMF) has been described as one of the 12 key platform molecules derived from biomass by the US Department of Energy, and its hydrogenation reaction produces versatile liquid biofuels such as 2,5-dimethylfuran (2,5-DMF). Catalytic hydrogenation from 5-HMF to 2,5-DMF was thoroughly studied on the metal nickel catalysts supported on Al2O3-TiO2-ZrO2 (Ni/ATZ) mixed oxides using isopropanol and formic acid (FA) as hydrogen donors to find the best conditions of the reaction and hydrogen donor. The influence of metal content (wt%), Ni particle size (nm), Nickel Ni-0, Ni-0/NiO and NiO species, metal active sites and acid-based sites on the catalyst surface, and the effect of the hydrogen donor (isopropanol and formic acid) were systematically studied. The structural characteristics of the materials were studied using different physicochemical methods, including N-2 physisorption, XRD, Raman, DRS UV-Vis, FT-IR, SEM, FT-IR Py-ad, H-2-TPD, CO2-TPD, H-2-TPR, TEM and XPS. Second-generation 2,5-DMF biofuel and 5-HMF conversion by-products were analyzed and elucidated using H-1 NMR. It was found that the (NiNiO)-Ni-0/ATZ3(WI) catalyst synthesized by the impregnation method (WI) generated a good synergistic effect between the species, showing the best catalytic hydrogenation of 5-HMF to 2,5-DMF using formic acid as a hydrogen donor for 24 h of reaction and temperature of 210 degrees C with 20 bar pressure of Argon (Ar).

Automated summary

The catalytic hydrogenation of 5-HMF to 2,5-DMF using Ni/ATZ mixed oxides as catalysts and isopropanol and formic acid as hydrogen donors was studied. The influence of various factors on the reaction and the characteristics of the catalyst were systematically examined. The best catalytic performance was achieved with the (NiNiO)-Ni-0/ATZ3(WI) catalyst synthesized by the impregnation method using formic acid as a hydrogen donor.