Preparation of mesoporous aluminosilicates with tunable morphologies and their effects on Fischer–Tropsch synthesis performance

ZSM-5 seeds grafted mesoporous aluminosilicates with different morphologies (SZM-1 (two-dimensional (2D) structure), MZM-2 (three-dimensional (3D) structure), MZM-1 (mixture of 2D and 3D structure)) were synthesized by varying benzene addition amount. These composites were used as supports for Co (20 wt%) catalysts, which were prepared by simple incipient wetness impregnation method. Their catalytic performance was evaluated by Fischer–Tropsch synthesis (FTS) reaction. The supports and corresponding catalysts were characterized by N 2 adsorption–desorption, XRD, TEM, H 2 -TPR, NH 3 -TPD techniques. 20Co/SZM-1 catalyst showed a highest FTS activity and best reaction stability, due to its higher cobalt dispersion, good cobalt reducibility and the confinement effect of two-dimensional structure. Compared to 20Co/SZM-1, 20Co/MZM-2 catalyst exhibited much higher selectivities to short-chain hydrocarbons and iso-paraffins, which may be attributed to the combination effects of its three-dimensional open pore structure and stronger acidity, leading to less diffusion limitation of hydrocarbon products and thus presenting a smaller chain-growth probability.