| Benzene is a widely used chemical raw material.Benzene comes mainly from by-product of petroleum processing.With the petroleum resource exhausts increasingly,benzene production may be restricted,the ethanol as one kind of green energy,will certainly substitute for the by-product of the petroleum as main material in chemical process in the future.Benzene and its derivatives were widely used in chemical industry as basic materials.The study on the high efficiency catalysts for synthesizing these materials with ethanol,has important significance.The catalysts which can catalyze ethanol aromatization were studied in this thesis.The Mo/ZSM-5 was the best catalyst for methane non-oxidative aromatization,and there were benzene formations over the Pt/CeO2 catalyst in the ethanol oxidative process.So,the Pt/CeO2 catalysts with different Pt, Mo/ZSM-5 with different Mo,M/ZSM-5(Cu,Sr,Co,Fe,Cd,Zn,Sb)and Using the Mo/ZSM-5 with 8%(wt)MoO3 loading as parent,the Pt/CeO2/Mo/ZSM-5 zeolite catalysts with same Pt loading and different CeO2 loading were prepared by impregnation method.These catalysts were characterized by XRD,BET and the NH3-TPD method.The results indicate that the surface area and acid amount of the ZSM-5 zeolite decreases with the Mo loading increasing.The results indicate that the Mo/ZSM-5 zeolite structural characteristics keep integrity basically after the Pt/CeO2 were loaded on it and calcined at 773 K.The catalytic behavior of ethanol aromatization over these catalysts,was performed in the flow fixed bed reactor.We got two kinds of catalysts with the capability of ethanol aromatization,we studied some factors which effect catalyzed performance,such as roasting temperature,roasting time, activation temperature and time.We also studied the life time of catalysts.The best catalyst is Pt/CeO2/Mo/ZSM-5.It indicates that the conversion of ethanol and the selectivity of benzene are 71.63%and 23.6%.We elementary extrapolated catalysis mechanism of ethanol aromatization.
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