| In the thesis, two entrapment methods were employed to prepare heterogenetic catalysts and their catalytic activities were investigated.First, the Alanine schiff base which was used as a ligand to coordinate with Mn(OAc)2 to prepare complex (Sal-Ala-Mn) was synthesized by the reaction of Alanine with salicylaldehyde. The structure of the obtained complex was characterized by FT-IR. Then the catalytic properties of the complex on the epoxidation of alkene were studied. The factors affecting on the catalytic activity and selectivity, which were reaction time and temperature, quantities of the Sal-Ala-Mn and isobutyraldehyde, and the volume of solvent were observed by using orthogonal test method. From the experiments it was found that the conversion of cyclohexene was 98.3% with a selectivity of 70.6% of 1,2-epoxycyclohexane when the reaction was run at the optimal conditions ( reaction time 10h, temperature 35 C, the molar quantities of the Sal-Ala-Mn to alkene 0.01, the molar ratios of cyclohexene to isobutyraldehyde and solvent 1:2:46).Second, physical entrapment catalysts were obtained by encapsulating Sal-Ala-Mn in SiOi matrix by sol gel method using methanol as solvent and muriatic acid as catalyst. Single factor layout was arranged to optimize the entrapment conditions. From the results we concluded the optimal entrapment conditions were that entrapment temperature, pH, R(H2O/TEOS) and drying temperature were 60 C, 4, 6, and 80 C, respectively. The content of Sal-Ala-Mn in the heterogenized catalyst obtained under the optimal entrapment conditions was determined by HPLC. It was found 0.245g of Sal-Ala-Mn was encapsulated in 30ml of TEOS. When the catalyst obtained under the optimal entrapment conditions was applied to epoxidation of cyclohexene, the conversion of cyclohexene was 98.2% with a selectivity of 87.2% of 1,2-epoxycyclohexane. The catalytic activity of the catalyst is almost same as that of the corresponding homogeneous catalyst. However, the selectivity has been hugely increased.Third, another heterogenized catalysts was obtained by the combination of sol-gel and chemical link technique ( anchored ). Single factor layout was also arranged to optimize the entrapment and catalytic reaction conditions. The optimal entrapment conditions were entrapment temperature 60 C, pH 3, R(H2O/TEOS) 6, drying temperature 80 C, respectively.The optimal reaction conditions were reaction time 6h, the quantities of the catalysts 0.175g, the molar ratio of cyclohexene to isobutyraldehyde 2, the volume of solvent 60ml, reaction temperature 35 C, respectively. Under the optimal conditions, the conversion of cyclohexene was 99.6% with a selectivity of 88.2%.Fourth, the catalytic properties of the homogeneous catalyst, the physical entrapment catalyst and anchored catalyst were compared at the same conditions. When the reaction was run at 35 C for 6h, the molar ratio of cyclohexene to isobutyraldehyde was 2, and the volume of solvent was 60ml, it was found that the anchored catalyst had the highest activity and the selectivity of 1,2-epoxycyclohexane. It was found that anchored one had a bigger specific surface area by N2 adsorption analysis. The surface properties and the contents of Mn of the two heterogenized catalysts were characterized by XPS and ICP, respectively. The results of XPS indicated that the 25.8% of Mn in the surface of the physical entrapment catalyst lost, while 17.4% of that of the anchored catalyst leaked after using one time. After recycled six times, almost all Mn in the surface of the physical entrapment catalyst disappeared, but the anchored catalyst had only 34.3% leakage of Mn. The results of ICP analysis indicated that 24.0% and 36.0% of Mn lost in the physical entrapment catalyst respectively after it was used one and six times, while the anchored catalyst had no leakage taking place. So the results indicated that the chemical link method is better than the physical entrapment method to solve the leakage of catalyst.Fifth, alanine Schiff-base iron metal comp...
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