| Methane is the component of natural gas, its activation and conversion has received much attention in recent years. Considering the prospect, environment protection and scientific research, utilization of methane resource is of significance. Methane non-oxidative aromatization is one of the main routes for methane direct conversion, since first reported in 1993, many research has focused on the study of this reaction. It is proved that Mo/H-ZSM-5, Mo/H-ZSM-11,Mo/H-MCM-22 and Mo/H-MCM-49 are the best catalysts for methane aromatization at present. But up to now, there is not a detailed study on the role of different pore sites of zeolite supports in the titled reaction. Especially, there is not a suitable method to distinguish the role of the three pore systems in MWW structure zeolites. The purpose of this thesis lies in: first, modify the external surface of HZSM-5, HMCM-49 and HMCM-22 with larger molecule organic compounds to change the acidic properties of zeolites and the dispersion of Mo species, and synthesize the MCM-36 zeolite by swelling and pillaring the MCM-22 precursor to change the pore structure of zeolites, and thus analyze the connection of the pore systems and catalytic activities on methane conversion. The main results obtained are as follows: 1. The synthesis of catalyst supports and the study on the synthesis condition. In the presence of template HMI, several zeolite molecular sieves such as MCM-22, MCM-49, MCM-56, MOR, ANA has been synthesized by dynamic synthesis method through the control of Si/Al ratios, alkalinity, crystallization temperature, time and other reaction conditions. It was found that the Si/Al ratios of reactant mixture were determinative to the phases of the products, while the alkalinity of reactant mixture has no effect on the products in certain range. 2. The role of the external surface of Mo/HZSM-5 catalyst. The selective modification of the external surface of HZSM-5 by large organometallic complexes was used to reduce the densities of external acid sites and MoOx species retained at external surfaces during the exchange process. The amounts of acid sites and the catalytic properties for non-oxidative aromatization of methane over modified and unmodified samples were studied. It was found that acid sites and active MoOx species mainly located within the channels of the modified zeolites, and the modified Mo/HZSM-5 showed higher shape-selectivity to major product benzene and lower formation rates and selectivities for naphthalene and coke. So we consider that the role of external surface acid sites is to promote the formation of larger hydrocarbons. 3. The role of the external 12-ring pockets over Mo/HMCM-49 catalyst. Four kinds of large molecular organic compounds were used to modify the external pockets of HMCM-49, and the physical properties, acidic properties, Mo dispersion and catalytic activities of modified and unmodified samples were studied by XRD, IR, TPD, BET, ICP, TGA measurements. It was found that the modification of HMCM-49 reduced the acid sites, the surface area and the dimension of microporous channel accesses. Otherwise, the modified catalysts...
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