Preparation of Ni/CeO2-Al2O3 by hydrothermal method and its catalytic selective hydrogenation of acetylene

xCeO2-Al2O3 supports with different CeO2 mass fraction (x%) were firstly synthesized by hydrothermal method, and Ni/xCeO2-Al2O3 with a mass fraction of 2% Ni was then prepared by initial wet impregnation method. The catalytic performance of Ni/xCeO2-Al2O3 on the selective hydrogenation of acetylene to ethylene was evaluated by XRD, SEM, H2-TPR, BET, XPS, NH3-TPD and TG. The results showed that Ni/5CeO2-Al2O3 exhibited excellent catalytic performance with an acetylene conversion of 99.7% and ethylene selectivity of 94.9% at 280 ℃. Ni/5CeO2-Al2O3 exhibited the largest specific surface area (164.2 m2/g) and pore size (7.2 nm), as well as the appropriate oxygen vacancy content [9.2%, calculated by Ce3+ peak area/(Ce3+ peak area+Ce4+ peak area), the same below]. The addition of CeO2 weakened the strong Ni/Al interaction, reduced the formation of inert NiAl2O4 spinel phase, and effectively improved the activity, selectivity and stability of the catalyst. Within 30 h, the acetylene conversion decreased to 90.0%, which was attributed to the carbon deposition during the reaction process reduced the specific surface area (151.5 m2/g) and pore size (6.6 nm) of Ni/5CeO2-Al2O3 © 2024 Fine Chemicals. All rights reserved.