| Zeolite molecular sieves is a kind of inorganic material with fine properties and extensive uses. Its well-defined crystal structure and surface abundance of silanol groups offer good supports to study the surface organometallic chemistry. Surface organometallic chemistry can modify or reform the surface of zeolite molecular sieves, on the other hand .directly or indirectly generate inorganic-organic heteromaterials with unique capabilities. It is more interesting to provide approaches of molecular researching to understand the microcosmic nature different physico-chemical processes (i.e.adsorption, atalytic) of the molecular sieves surface through investigations of properties of organometallic compounds with well-defined structure and composition on the surface of zeolite molecular sieves .In our study: 1) the grafting reaction of alkyltin compounds (alkyl=methyl, ethyl, propyl, butyl) on the surface of zeolite molecular sieves with different composition, structure and properties (Y, (5, ZSM-5, MCM-41) were systematically studied under high vacuum condition. The composition , structure of solid and gaseous products and the stoichiometry of the reaction had been fully characterized by elemental analysis, ICP, GC, GC-MS, in situ FTIR, MAS NMR, XRD, XPS, DRS, TPD, TPR, TG . The BET surface area and the adsorption capacities for different dimension hydrocarbons had been determined. Make clear the universal rule of the reaction of alkyltin compounds on the surface of zeolite molecular sieves, including the stoichiometry of the reaction, the selectivity of the pore of zeolite to organometallic compounds, the effect of the surface hydroxyl acidities of zeolite on the reaction, the appropriate reaction temperature, the mechanism of the reaction, the composition and structure of the solid products. 2) Study the mechanism of the reaction of zeolite with onganometallic compounds: the kinetics of the tetramethyltin reacting with the surface hydroxyl of Y zeolite, determine the rate of evolved gas during the grafting reaction at various temperature, calculate the apparent activation energy. 3) The thermal stabilities of modified zeolite molecular sieves were investigated .4) Based on the above research, adopting molecular designing idea and the conception of surfaceorganometallic chemistry, we explored the designing and reconstructing surface of molecular sieves in practical application. The Pt-Sn/NaY molecular sieves synthesized were used in hydrogenation of furfural to furfuryl alcohol. We discussed its catalytic performance and selectivities in this reaction.The innovated results of our researches were:l) the supercages surface hydroxyl of HY zeolite could react with SnMe4, SnEt4, SnPr4 and SnBu4 at 183, 243, 273, 333 K, respectively. 1 g HY zeolite reacting with excessive tetraalkyltin could make 1.71, 1.40, 1.12, 0.85mmol tin grafted on the surface. The zeolite had retained its crystalline structure after grafting the alkyltin compounds, forming the mono-grafted species (≡Si-O)SnR3 on the surface. However, its surface acidities had decreased, leading to the prominently shape-form selectivity of the adsorption capacities for larger molecular hydrocarbons. Tetramethyltin could react very rapidly with hydroxyl groups of HY zeolite at low temperature. The apparent activation energy was only 10.4 kJ mol-1. 2) the surface hydroxyl of Hβ, ZSM-5 and MCM-41 could also react with tetramethyltin at 193, 223, 343 K, respectively. The amounts of grafted tin on 1 g zeolites were 1.06, 0.146, 0.76 mmol and tin was tetra-coordinated. After modified by tetramethyltin, the microporous structure of Hβ and ZSM-5 and the mesoporous structure of MCM-41 were not changed. The thermolysis temperatures and the decomposition processes of the grafted species were different due to the difference of the structure and surface acidities of the molecular sieves. The order of zeolite molecular sieves according to their thermal stability was SnMe3/MCM-41>SnMe3/HY>SnMe3/H β >SnMe3/ZSM-5. 3) The selectivity of furfuryl alcohol were improved 20% over Pt-Sn/...
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