Effect of the Nature of Ni Species on Hydrogenation of 1,4-Butynediol over Ni/SiO2 Catalysts

The catalytic performance of liquid-phase hydrogenation of 1,4-butynediol (BYD) to 1,4-butanediol (BDO) was studied on silica-supported Ni catalysts prepared by impregnation, sol-gel, and ammonia evaporation methods, respectively. Due to the formation of nickel phyllosilicate, the Ni species in Ni/SiO2-AE catalyst prepared by ammonia evaporation is difficult to reduce at 450 degrees C, resulting in fewer Ni0 active sites and poor hydrogenation activity. As for the impregnated Ni/SiO2-IM, its nickel particles are prone to aggregate seriously due to their weak interaction with the support which may be not conducive to catalytic hydrogenation. On the contrary, the Ni species introduced by sol-gel method can homogenously embedded in the amorphous silica intersecting network structure with high metal dispersion and well physical confinement effect, which greatly promotes its BYD hydrogenation performance to obtain BDO with super high selectivity.