Study on deactivation of Ni/Al2O3 catalyst for liquid phase hydrogenation of crude 1,4-butanediol aqueous solution

Abstract The deactivation of a commercial Ni/Al 2 O 3 catalyst in the liquid phase hydrogenation of crude 1,4-butanediol aqueous solution was investigated. A significant deactivation trend was observed during the operation time of 5000 h. The fresh and deactivated catalysts were characterized by ICP-AES, N 2 physisorption, H 2 -TPR, TEM, TPD, FTIR and XRD. The results indicate that, during the reaction process, the Al 2 O 3 support transforms into its hydrate boehmite (γ-AlO(OH)), which further results in the aggregation of metal Ni, the decrease of BET specific surface area and the reduction of pore volume. The hydration of Al 2 O 3 support is the main reason for the deactivation of Ni/Al 2 O 3 catalyst. The promotion effect of SiO 2 on the activity and stability of Ni/Al 2 O 3 catalyst was also investigated. The results suggest that the introduction of SiO 2 effectively inhibits the hydration of Al 2 O 3 support and prevents the active decay of Ni/Al 2 O 3 catalyst.