The Synthesis Of Microporous Molecular Sieve Materials And Exploitation Of New Synthesis System

Microporous zeolite materials with uniform , molecular-size and adjustable channels or cages, have been used in many fields such as ion exchange, adsorption and separation, industrial catalysts, et al.. How to control the morphology of the microporous zeolite has attracted more interesting research efforts. With the development of the synthesis of the zeolites, many new applications have been emerged such as on the preparation and development of the host materials for optical or optoelectronic molecules which base on the synthesis of the zeolite films, large zeolite crystals or with other morphologies. However, the applications of such functional materials are based on theire special morphology. For example, the zeolite nanocrystals with high diffusion, surface area, and pore volume will lead to their high accessibility and fast mass transport in industrial catalysis application. The large single zeolite crystals are very important to investigate the zeolite growth mechanism and preparation of micro-device utilizing zeolites as host materials. The applications of the functional materials, especially micro-devices, are based on handful morphology, higher quality and orientation membrane, as well as lager size of zeolites crystals. Therefore our research work focused on the syntheses of zeolite with special morphologies.Synthesis of zeolite silicalite-1 with chainlike morphology. Zeolite Silicalite-1 with chain morphology (0.57-6.33μm) was synthesized successfully with Poly(diallyldimethylammonium chloride) (PDDA) as an additive, which the largest ratio of length and width is nearly 10:1. According to the characteritic results of XRD and SEM, the amounts of PDDA and TPAOH have directly effect on the length and diameter of the chains. Chainlike MFI zeolite with the length 6.33μm and the diameter 0.9μm has been synthesized through adjusting the molar ratios of PDDA and TPAOH. The materials may improve the selectivity of separation for hydrocarbons, because of the crystal stacking along the b axis. The straight channels of materials are longer and their openings are much fewer than those of the traditional slicalite-1 crystals.Synthesis of Micropatterned Oriented Zeolite Monolayer Film. Unique properties of zeolite films have been utilized for a variety of applications such as separation, membrane reactors, chemical sensors, microreactors, low-dielectric constant films for computer chips. The ability to micropattern a zeolite film or to selectively grow a zeolite film in a desired area is a critical issue to realize many of its potential applications such as low-k dielectric films, sensors, and microreactors. Here, various kinds of micropatterned oriented zeolite films by a new soft lithography technology have been synthesized successfully, which are stable than others by synthesized by employing"soft lithography"and by using zeolite nanocrystals as building blocks. Furthermore, we can prepare various kinds of micropattern zeolites films according combination of different mask. Such films will be applied in detection of biology molecule, gas molecule and preparation of phonic crystals et al.Zeolites are well-defined and well-organized host for the preparation of nanoclusters, host-guest functional materials, due to their one-dimensional (1D), two-dimensional (2D) nano channels or cavities, and have been widely used in fundamental and applied researches. However, many challenges still remain in realizing the application of zeolites in pyroelectronic microdevices. One of the most important obstacles is the synthesis of high-quality zeolite giant single crystals. The large single zeolite crystals are prepared through controlling supersaturation level, nucleation rate, and the release of silica species. For example, LTA,FAU,SOD single zeolite crystals are synthesized by addition of nucleation suppressor, MOR single zeolite crystals by"two silica sources"technology, MFI, ANA and SOD by BMD ( Bulk Material Dissolution) method, et al.. Here, we control the nucleation rate by"seed solution"of Beta zeolite as an additive. The single MOR zeolite crystal has been synthesized successfully. The size of crystals can be controlled by adjust the amount of"seed solution". In limited domain, the amount of alumina influences the morphology of crystals, because it may change the chemical potential of the solids and oligomer.The hypothetical structures of zeolites are more than 1,000 types, which attracted more interest to scientists. Unfortunately, zeolite synthesis is a difficult and complex process. So, it is a important issuet that exploitation of new synthesis systems, methods and routes. Here, we try to synthesize zeolite or MOFs with novel structures with the ionic liquids as solvent. Two new structures of metal-organic framework compounds with new structures are synthesized successfully with 1-butyl-3- methylimidazolium BF4 as solution. X-ray powder diffraction demonstrates that compound 1 belongs to Monoclinic Crystal system, C2/c space group. Compound 2 belongs to orthorhombic Crystal system, Fdd2 space group.Ionic liquids are a class of organic solvents with high polarity and a preorganized solvent structure. Room temperature (or near-room-temperature) ionic liquids are classically defined as liquids at ambient temperatures (or<100°C) that consist only of ions. They have excellent solvating properties, little measurable vapor pressure, and high thermal stability. Ionothermal synthesis is a novel methodology for the synthesis of zeotype materials and inorganic–organic hybrid materials. Interest in this methodology is growing, and it can be expected that in the near future there will be further publications reporting new and exciting structures and developments.