Modification of Ni-B/TiO2-Al2O3(S) amorphous alloy catalyst by Mo for liquid-phase furfural hydrogenation

The effects of Mo on the catalytic and surface properties of amorphous alloy Ni-B/TiO2-Al2O3(S) had been studied. Liquid-phase furfural hydrogenation to furfural alcohol was selected as probe reaction. The properties of the catalysts were characterized using ICP, DSC, N-2 adsorption, TPD, and TPR, respectively. The catalytic activity of Ni-B/TiO2-Al2O3(S) was higher than that of Ni-B/gamma-Al2O3, which was due to the more Ni content in the former. Moreover, the decrease of micro-pore number leaded to higher selectivity, since the diffusion of the product in micropore was difficult. The addition of Mo could make Ni be reduced easier, produce new active centers over the surface of the catalyst, weaken the strength of Ni-H bond, and increase the number of adsorption centers, which resulted in the increasing activity of Ni-B/TiO2-Al2O3(S). Mo could enlarge the average pore size and volume, resulting in the easier diffusion of furfural alcohol to the surface of catalyst. At the same time, the results of TPD showed that Mo made furfural alcohol desorb easier from the catalyst surface. Therefore, the selectivity of the catalyst was improved. When Mo Content was 1.25%, both of the activity and selectivity of the catalysts reached to 100%.