Selective hydrogenation of levulinic acid to γ-valerolactone on Ni-based catalysts

In this work, Ni-based catalysts were prepared using the impregnation method. Ni/Al 2 O 3 showed good performance with a γ‐valerolactone (GVL) yield of 99.2% from hydrogenation of levulinic acid (LA). Among the tested bimetallic catalysts , the NiCo catalyst showed better performance than NiMn, NiMo, and NiCu catalysts for the hydrogenation of LA to GVL. Catalysts with different Ni/Co ratio were synthesized, and 15%Ni-15%Co/Al 2 O 3 shows the best performance with a GVL yield of 99.5%. The textural and chemical characteristics of the NiCo/Al 2 O 3 were determined by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS) and H 2 temperature-programmed reduction (H 2 -TPD). This study shows that the incorporation of the Ni and Co metals formed a Ni-Co alloy, which significantly increased the activity than other Ni-based bimetallic catalysts and led to a milder condition for hydrogenation of LA to GVL. The test of reuse potential of 15%Ni-15%Co/Al 2 O 3 exhibited good stability up to 5 cycles without obvious deactivation.