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The selective catalytic oxidation of cyclohexene has been one of the most compelling research topics in the field of catalytic chemistry today, therefore, has been catalytic fields of science and industry, widespread concern. The industrial production of hydrogen peroxide epoxidation method but H2O2 expensive, and explosive safety hazards. Therefore, the use of safe, clean, inexpensive molecular oxygen as oxidant catalytic system because of its academic and economic value of research significance. Reported in literature so far catalyst for oxygen epoxidized, are divided into two categories, one for the homogeneous catalyst, but there is not easy separation and recovery, and difficult to re-use and stability of the shortcomings of low; other for load type The heterogeneous catalyst, mainly by metal complexes or polynuclear metal complexes supported on a heterogeneous carrier, they are the preparation process is complicated, expensive, and easy to loss of active ingredient, and the use of aldehydes expensive. the epoxycyclohexane selectivity was 91%. Design and screening performance and easy separation of the catalyst of the recovery, to find the best way of activation of molecular oxygen, the cyclohexene epoxidation research topics for future efforts in the direction. Thesis prepared by different methods of transition metal modified mesoporous materials and zeolite catalysts: in situ synthesis prepared by modified SBA-15, MCM-41 mesoporous material and TS-1 zeolite; ion exchange or impregnation Preparation of modified Y and ZSM-5 zeolite; citrate method and prepared by solid metal aluminum phosphate catalyst. Means on the physical and chemical properties of the catalyst prepared were characterized by XRD, IR, TEM, BET, and then apply it to the epoxidation reaction of cyclohexene / molecular oxygen, as a reduction in acetonitrile as solvent, benzaldehyde agent conditions, a preliminary study of its catalytic properties. The effects of the the reaction aldehyde allyl ratio, amount of catalyst, reaction temperature, time, and other factors epoxidation of cyclohexene synthesis process, single factor optimization optimum conditions. The results show that, in the O2 / benzaldehyde system, SBA-15 as a base body doped metal-modified catalyst can be high for the selective catalytic oxidation of cyclohexene epoxycyclohexane. Among them, the best catalytic activity, epoxycyclohexane in a yield of 62.01% La-SBA-15 as a catalyst for cyclohexene epoxidation reaction. Next, a Cu-MCM-41 (acidic media), Ni-TS-1, the catalytic activity of Cu / Y, LaAlPO (citric acid method) and LaCuAlPO (solid phase method) is preferably oxygen cyclohexane yields were 57.64%, 52.16%, 57.72%, 58.86% and 53.25%, respectively. In summary, the mesoporous materials prepared in this thesis a series of the active metal component-modified novel catalysts and molecular sieves, these catalysts for the epoxidation reaction of cyclohexene / molecular oxygen no literature, and the catalyst having good catalytic performance, easy separation and recovery of the expected long life characteristics; benzaldehyde as a co-reductant is much lower compared to the other n-butyraldehyde, isobutyraldehyde, neopentyl aldehydes such price. Cyclohexene / molecule of oxygen Epoxidation showed good prospects for development, and further research work is still in progress.
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