| Zeolites are the most popular porous materials. The uniform pore distribution, high stability and high BET surface make the zeolites good catalysts in some catalytic reaction. With the expansion of the application, the demand for the zeolites with new structure and properties grows rapidly, and the study of zeolites was transformed to the synthesis of the ones with new structure, and the synthesis of the new multidimensional porous zeolites using diquaternary ammonium compounds attract the interests. The diquaternary ammonium compounds have many advantages that small rigidity molecules don't, just like the rich flexibilities and the higher charge density of the skeleton.IM-5 is a kind of microporous zeolite with 2-dimensional intercommunicated pore structure. It was usually synthesized using MPPB as the structure directing-agent (SDA) under the kinetic hydrothermal conditions in which the synthesis of SDA and the zeolites was separately. In this method, there exist some problems such as narrow synthetic distribution, long synthetic cycle and low efficiency. In our work, the in-situ template method was used in which the mixture of DBP and NMP was replaced the SDA so that two synthesis step become one. During the preparation of the synthesis gel. the DBP and NMP were reacted to generate the MPPB which lead to the crystallization of IMF structure. With the new method, the synthesis route was streamlined and the synthetic efficiency was improved during the synthesis of IM-5 zeolite.We investigated the relationship between the synthetic factors including NaOH/Si ratio. Na/Si ratio. Si/Al ration and the results of the synthesis under the in-situ template system. It was found that the suitable Si/Al ratio for the synthesis of IM-5 was between 10～30. The proper NaOH/Si ratio for the synthesis of IM-5 zeolite may be 0.65. and the lower NaOH/Si ratio would lead to the MTW structure while the MOR structure was the main phase in the higher NaOH/Si ratio condition. With the increase of Na/Si ratio, the quartz appears first followed by the IMF phase, and the MTW. MOR appeared in the high Na/Si ratio condition. After that, we try to synthesis the Ti doped IM-5 zeolite, three different methods was used including direct hydrothermal synthesis, atom-planting method and the Si-Ti precursor method. The product gained from different routes shows different in somewhere. The direct hydrothermal method could only be applied when the Si/Ti>500. so that the product is meaningless because of the extremely low Ti content. There exist 3 Ti species in the product gained from the atom-planting method including the tetrahedral coordinated Ti. the 5-8 coordinated Ti and the crystal TiO2 separately, and the TiO2 in these materials could not be removed by the acid treatment. In addition, the calcination could affect the status of the Ti species in the product. The Ti existed in the product gained from the Si-Ti precursor method was mainly in the form of tetrahedral coordinated Ti. and the inducing of Ti atom to the framework change the lattice parameters of the IM-5 zeolite.In order to investigate the catalytic properties of the IM-5 and Ti-IM-5 zeolite, the protonated IM-5 zeolite was used as the catalyst in the reaction of the transformation of the sucrose while the Ti-IM-5 was applied in the epoxidation of the 1-octene reaction. In the reaction of the transformation of the sucrose, the IM-5 showed a good reaction activity, according to the reported relative literatures, there exits some Lewis acid center in the protonated IM-5 zeolite. In the epoxidation reaction, the H2O2 was used as the oxidant, when the CH3CN was used as the solvent, Ti-IM-5 showed good selectivity (close to 100%) to the hexyloxirane (HO) which is wanted product of the epoxidation reaction while the IM-5 zeolite showed no activity in this reaction. When the CH3OH and Ti-IM-5 were used as the solvent and the catalyst separately, the 1.1-dimethoxyheptane (DMH) and the 1,2-octanediol (OTD) became the products instead of HO. So solvent is important in the epoxidation reaction, and the aprotic solvents like CH3CN may the suitable choice when the Ti-IM-5 was selected as the catalyst. |
