Hierarchically macro-/mesoporous structured Al2O3 and TiO2-Al2O3 materials were used as supports to prepare novel Co-Mo-Ni hydrodesulfurization(HDS) catalysts. A commercial Co-Mo-Ni/Al2O3 catalyst without macroporous channels was taken as a reference. The catalysts were characterized by scanning electron microscope(SEM), transmission electron microscope(TEM), energy-dispersive spectrometry(EDS), N2 adsorption-desorption, X-ray diffraction(XRD), and temperature programmed reduction(TPR). The apparent activities of the hierarchi-cally porous catalysts for thiophene HDS were superior to those of the commercial catalyst, which was mainly as-cribed to the diffusion-enhanced effect of the hierarchically bimodal pore structure. The addition of titania to alu-mina in the support helped to weaken the interaction between the active phase and the support, and as a result, the novel Co-Mo-Ni/TiO2-Al2O3 catalyst with a low titania loading(28%, by mass) in the support exhibited high HDS activities, even without presulfiding treatment. However, the catalyst with a high titania loading(61%, by mass) showed much lower activities, which was mostly caused by its low surface area and pore volume as well as the non-uniform distribution of titania and alumina. The kinetic analysis further demonstrated the support effects on HDS activities of the catalysts.
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