Selective Production of 2-Butanol from Hydrogenolysis of Levulinic Acid Catalyzed by the Non-precious NiMn Bimetallic Catalyst

Selective production of 2-butanol from levulinic acid (LA) hydrogenolysis over a non-precious catalyst is long desirable. However, the process requires the precious metal Ru, and the yield of 2-butanol was less than 65%. Herein, we prepared Ni-based bimetallic catalysts, among which the NiMn catalyst exhibited the highest efficiency and reached an 84.5% yield of 2-butanol at 100% LA conversion under optimal conditions. The electronic states and surface properties were characterized by various techniques such as X-ray diffraction, X-ray photoelectron spectroscopy, temperature-programmed desorption, temperature-programmed reduction, and scanning electron microscopy/transmission electron microscopy. The high efficiency of the NiMn catalyst was due to the synergy between Ni0 and Mn2+ species, and the modified surface showed a high basicity and a high affinity to adsorb LA and LA-derived molecules with C═O or COOH. The high affinity of the NiMn catalyst was further confirmed by density functional theory calculations.