| Porous materials are widely used in many fields, such as catalysis, adsorption, and separation, of which, mesoporous silicas, carbon molecular sieves and aluminophosphate molecular sieves are of great importance. Mesoporous silicas with tunable pore structures have been attracted much attention, but the preparation methods for these materials are limited. Microporous carbon molecular sieves with special shape and highly dispersion are demanded in many applications, however there is limited facile and effective way to prepare them. Zeolite molecular sieves are usually synthesized by hydrothermal method. Recently, the application of the combinatorial chemistry in the hydrothermal synthesis of zeolites accelerates the screening and evaluation of zeolite synthesis. On the other hand, zeolite molecular sieves can also be prepared by the vapor phase transport (VPT) technique. Various zeolite molecular sieves, mainly aluminosilicates, had been synthesized by this technique. The novel combinatorial method has not been used for the synthesis of zeolitic materials by the VPT technique, however. In order to address the questions posed above, the following three parts of works were carried out in this dissertation as follows: (1) preparation of mesoporous silicas with tunable structure, (2) preparation of highly dispersed spherical carbon molecular sieves and (3) development of the combinatorial vapor phase transport method and its application on the synthesis of SAPO-34 molecular sieve. A novel approach to the synthesis of mesoporous silicas with tunable pore size, pore volume and pore structure was presented. Organic poly(furfuryl alcohol) (PFA) was incorporated into silica walls by co-polymerization of furfuryl alcohol (FA) and silica source such as tetraethyl orthosilicate during the triblock copolymer P123 templating process. Mesoporous silicas with wormhole pore structure were obtained by completely burning off organic polymers P123 and PFA from the PFA-silica nanocomposite frameworks, and their pore size and pore volume were enlarged by simply adding more FA. TGA, N2 adsorption-desorption, SEM, TEM and FT-IR were used to characterize the Silica-P123 and Silica-P123-PFA nanocomposites, and their final mesoporous silicas. It is suggested that the P123 templating mechanism is not changed by addition of FA under our experimental conditions, which is evidenced from the similar pore structure and pore size before PFA removal. When the large amount of FA (e.g. 2.12FA: 1SiO2 by mole) was used in the synthesis, the pore size was expanded from 3.4 nm to 7.4 nm, and the pore volume was increased from 0.46 cm3/g to 1.37 cm3/g. In the meantime, the pore size distribution was broadened. The BET surface area of the mesporous silicas was determined to be 632-728 m2/g. Highly dispersed microporous carbon molecular sieve spheres with an average size of 260 nm-1.5 μm were prepared by carbonization of "nonstick"poly(furfuryl alcohol) (PFA) spheres, which were synthesized by a two-step polymerization of furfuryl alcohol (FA) involving slow polymerization (1st step) in the surfactant solution and sphere formation (2nd step). The high dispersibility of the carbon molecular sieve spheres was simultaneously realized by removing surface functional groups of the PFA spheres with the evaporation-induced concentrated sulfuric acid (2nd step). By varying the temperature of slow polymerization, the spheres with different size could be simply synthesized. Surfactant (P123 and F127) and sulfuric acid treatment played an important role in the synthesis of highly dispersed PFA spheres and carbon molecular sieve spheres. 5 M sulfuric acid was optimized. Smoother surface of carbon molecular sieve spheres could be obtained when F127 was as surfactant in comparison to P123. The microporous structure were almost the same with BET surface area of 359-392 m2/g, pore volume of 0.14-0.15 cm3/g and pore size of ca. 0.564 nm with the two surfactants. The combinatorial vapor phase transport method was developed by designing a multiwell reactor, which is suitable for the combinatorial VPT synthesis of zeolites and zeolite-like materials. By using this method, a series of syntheses could be carried out in one reaction, and the samples could be rapidly examined. The preparation of SAPO-34 was taken as an example and the synthesis factors, such as SiO2/Al2O3 ratio, P2O5/Al2O3 ratio, types of the organic amines in liquid phase, the reaction temperature and time, were systematically examined. It was found that SAPO-34 can be readily synthesized from the dry gels prepared with SiO2/Al2O3 of 0.5-0.75 and P2O5/Al2O3 of 0.93-1.25, with water to triethylamine (TEA) ratio of 10-50: 1.0 in the liquid phase, a reaction temperature of 443-453 K and a reaction time of 48 h. These results indicated that Combinatorial VPT synthesis provides a rapid and efficient way on the synthesis and evaluation of zeolites and zeolite-like materials. In addition, vapor phase transport syntheses of SAPO-34 were carried out using dry gels containing the template and volatile organic amines in the liquid phase. The templates presented in the dry gels were TEA, tetraethylammonium hydroxide,diisopropylamine (DiPA) and morpholine (MOR), respectively, and the volatile organic amines in the liquid phase were TEA, DiPA and MOR, respectively. It was found that SAPO-34 with different properties, such as crystallinity, crystal size, and acidity, could be synthesized with the change the SiO2/Al2O3 ratio, H2O/TEA ratio in the liquid phase, water content in the precursor solution, the reaction temperature and time. Cross-linked polyacrylamide (PAM) hydrogels were employed to reduce the crystal size of SAPO-34 molecular sieve in the vapor phase transport process. SAPO-34 crystals with a wide size distribution ranging from a few nanometers to 3-10 μm were produced when the synthesis precursor gels contained the appropriate amount (x=0.29-0.43, x was defined as the molar ratio of polyacrylamide to Al2O3) of PAM hydrogels. These crystals exhibited BET surface area of 342-325 m2/g, micropore volume of 0.15-0.12 cm3/g, and TEA entrapment of 9.3%-8.0%. EDX analysis showed that there existed excessive starting materials such as phosphorus precursor in the obtained samples, which supported that our samples possessed lower BET surface area and micropore volume as compared with the SAPO-34 prepared by hydrothermal method in the literature. Vapor phase transport technique was successfully used in the preparation of SAPO-34 coating on the cordierite honeycomb monolith. The monolith was first immersed in the precursor solution of SAPO-34 for a specified time and dried. This process was repeated for 2-4 cycles and then the vapor phase transport syntheses were carried out. It was found that the weight of SAPO-34 loaded on the monolith could be adjusted by changing the impregnation time and the SiO2/Al2O3 ratio. When the monolith was impregnated in the precursor solution for 10 min and the impregnation and drying process was repeated for 3 cycles, SAPO-34 layer with a thickness of 60 μm and a crystal size of 2 μm on the monolith was obtained. SEM and ultrasonic treatment of the SAPO-34 layer indicated that SAPO-34 was tightly bonded on the monolith.
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