One-pot conversion of biomass-derived levulinic acid to furanic biofuel 2-methyltetrahydrofuran over bimetallic NiCo/γ-Al2O3 catalysts

The production of furanic biofuel 2-methyltetrahydrofuran (2-MTHF) has been studied by hydrodeoxygenation of biomass-derived levulinic acid (LA) over bimetallic NiCo/γ-Al2O3 catalyst. The contents of Ni and Co in NiCo/γ-Al2O3 were investigated. The Ni5Co25/γ-Al2O3 catalyst gave high activity in hydrodeoxygenation of LA with a 73.4% yield of 2-MTHF under optimal conditions. The crystal phase, valence states, acidity and basicity of catalysts were measured by multiple characterizations to understand the relationships among 2-MTHF yields and catalyst properties. XPS characterization revealed that the number of metal oxides increased on bimetallic catalysts while the reduced metals occupied on monometallic catalysts. The bimetallic catalysts also presented increased acidity than that of monometallic catalysts. These distinct properties were also observed among bimetallic catalysts with different contents of Ni and Co, which were responsible for different performances. Besides, the solvent effect on the structure of 1,4-pentanediol, which was further converted to 2-methyltetrahydrofuran, was disclosed by molecular dynamics simulations.