| Titanium silicalite (TS-1) is a novel type molecular sieve,appearing in the last decade. It gives new chance for the studies of the catalytic oxidizing reactions and the developing of the environment-friendly chemical engineering progress. But,the classical hydrothermal synthesis method of TS-1 has lots of defects,such as the costly raw materials,the severe reaction conditions,and so on. The industrial proceeding of the use of titanium silicalite as catalyst is hindered seriously by the synthesis of this titanium-containing material. Compared to the classic hydrothermal method,the gas-solid preparation way can be used to study the synthesis of TS-1 from more extensive field,based on the synthesized precursor. Besides,the operating conditions of the gas-solid reaction are not vigor and the raw materials are very cheap. So,study on this technique has become one of the most important directions in the field of the titanium silicalite. The results show that this part work is still on the exploratory stage. Including the effects of the gas-solid reaction conditions,the reaction mechanism is not clear to be understood. Further,the framework titanium content can not be controlled effectively by this method. The present situation seriously affects the gas-solid technique to be developed further. This paper investigates thorough the gas-solid reaction mechanism and the incorporating progress of the Ti atoms into the framework,by the systematic studies of precursors with different physicochemical property and the use of several kinds of spectroscopies. Based on these works,a new plot of the gas-solid method,"nest-constructing-titanium-planting",is produced for the first time to control effectively the titanium content incorporated into the framework. This plot opens a new route for the raise of the preparation level of the gas-solid method.According to the present theory studies,the structure and the function mode of the catalytic reaction centers are analyzed only based on the study of the framework titanium. On the contrary,the thesis investigate the nature of the catalytic reactive centers in titanium silicalites based on both the framework tetrahedral Ti4+ and the mononuclear and isolated nonframework TiOx,combining the results of the spectroscopies and the catalytic property of epoxidation of propylene.In this paper,the preparation of Pentasil type titanium-containing molecular sieves has been performed by using gas-solid reaction. The chosen precursors are three type Pentasil molecular sieves:aluminium-containing,highly siliceous and boron-containing molecular sieves. In addition,the effects of different pretreatment of precursors on preparation are also completed. XRD,FT-IR,UV-Vis,XPS and 29Si,27A1,11B MAS NMR techniques are used to characterize the surface structural properties of molecular sieves before and after the gas-solid reaction. Then the mechanism of the insertion of Ti atoms in the framework is analyzed based on these characteristic results. The suitable conditions of the gas-solid reaction are obtained through the investigation of the reaction temperature,time and the speed of the carrying gas N2.To effectively control the content of framework titanium,the amounts of silanol nests in precursors framework are regulated before the gas-solid reaction. This technique is named as "nest-constructing-titanium-planting".For the industrial application and fundamental investigation,the catalytic properties of Ti-ZSM-5 on the epoxidation of propylene with H2O2 are studied and the effects of reaction temperature,reaction time,pressure of propylene and amounts of H2O2 and catalyst are investigated either. The presure of theintermediate reactive center of framework titanium with five-mumbered cyclic structure is tested by the experiments of solvent and additive acid and base effects. Besides,the reaction mechanism is deduced from the experimental results.In addition,large pore titanium-containing (BEA type) and M (MOR type) zeolites have been prepared by using their responding dealuminat...
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