【作者】 殷成阳；

【导师】 肖丰收；

【作者基本信息】 吉林大学 ， 无机化学， 2009， 博士

【摘要】 微孔材料、介孔材料等多孔材料已经广泛的应用于工业催化、吸附等领域。但微孔沸石由于其较小的孔径限制了其在大分子催化反应上的进一步应用;而介孔分子筛最大的弱点是水热稳定性差、催化活性较低。现实迫切需要发展综合微孔沸石和介孔分子筛材料优点的新型材料,即根据应用需要和结构特点来合成介孔沸石材料。本论文从几个不同的角度出发,包括降低合成成本,简化操作程序,绿色环保等方面,从而开发出简单高效的介孔沸石材料的合成方法,同时重点考察介孔沸石材料的催化性能,通过其在几个不同的催化反应中所表现的特性,希望可以更好的对介孔沸石材料进行比较深入的研究。第一章为绪论部分,首先简单概述了多孔材料的发展历史及其催化性能研究的一些进展情况;然后重点介绍了介孔沸石材料的合成方法及催化性能的相关研究进展;并对本文涉及的几个典型催化反应进行了较详细的介绍。第二章中采用阳离子聚合物做为介孔模板,通过一步水热的方法合成出介孔Beta沸石,通过调节加入聚合物的量可以调节所合成样品的介孔孔容,样品在酸量上也有所区别。第三章中仔细研究了该介孔Beta沸石的催化活性,该样品在苯和异丙醇的烷基化反应中展示了很好的催化活性,而且具有较好的催化剂寿命,并对其原因进行了探讨。第四章中以一类面包做为介孔模板,通过一步水热的方法合成出介孔ZSM-5沸石,该合成方法非常简单,模板原料易得,成本较低。该材料在1,3,5-三异丙苯的裂化反应中展示了优良的催化活性,样品即使在水热处理后依然具有很好的活性。第五章是结论及展望。更多还原

【Abstract】 Nowadays, porous materials are of interest for catalysis, adsorption, separation and other applications. Zeolites as solid acid catalysts have been widely used in industry as heterogeneous catalysts, However, relatively small and sole micropores in zeolites strongly influence the mass transport, which severely limit their performance of industrial catalysts. Ordered mesoporous aluminosilicates were synthesized to solve the diffusion limitation of microporous zeolites. But these mesoporous aluminosilicates exhibited lower hydrothermal stability, weaker acidity, and lower catalytic activities than microporous zeolites which was attributed to their amorphous framework, which limited the performance of mesoporous aluminosilicates in catalytic field.To overcome these limitations, various methods such as synthesis of nanosized zeolites, invention of various ultralarge-pore zeolites and ordered mesoporous materials with higher hydrothermal stability had been successfully pursued. To change the amorphous walls of mesoporous materials, a series of ordered mesoporous aluminosilicates were synthesized by assembly of preformed nanosized zeolite precursors as aluminosilicate sources with surfactant micelle. Compared with conventional zeolites, the hydrothermal stability of these mesoporous aluminosilicates was still low, which was attributed to the semi-crystallized mesoporous walls. Some efforts have been devoted to the development of mesoporous zeolites, with the aim of combining the advantages of the high acidity and high hydrothermal stability of the crystalline zeolite and the facile diffusion of bulky molecules in mesoporous materials.Mesoporous zeolite materials, which are defined as the zeolite crystalline materials containing a large amount of mesopores, not only inherit excellent acidity and hydrothermal stability, but also improve the adsorption and diffusion of large molecules. Mesoporous zeolite materials have much effective and potential applications in catalysis, especially catalytic reaction over large molecules.Recently, mesoporous zeolites from carbon templates had been successfully synthesized, but their applications are still limited by the complexity of synthetic procedure and hydrophobicity of carbon templates.The aims of the present paper are: to develop facile, low cost and efficient routes to novel mesoporous zeolites. To characterize the structure and properties of mesoporous zeolites. To analyze the interaction factors during the synthetic system. To investigate the applicability of mesoporous zeolites to catalysis.We demonstrate here a unique, facile, controllable, and universal route for the synthesis of mesoporous zeolites. More importantly, these novel mesoporous zeolites exhibit excellently catalytic properties, compared with conventional zeolites.Mesoporous Beta zeolite is synthesized from a mixture of small organic ammonium salts and mesoscale cationic polymers as template. The route involves a one-step hydrothermal synthesis, and the templated mixture is homogeneously dispersed in the synthetic gel. Mesoporous Beta exhibited a better catalytic activity in reactions of alkylation of benzene with isopropanol than conventional Beta.Mesoporous ZSM-5 zeolite with hydrothermal stability and high catalytic activities has been successfully synthesized from a mesoporous template of bread. The bread with environmental benignity, abundant porosity, and good hydrophilicity is suitable and beneficial for the facile synthesis of zeolites with mesoporosity. Mesoporous ZSM-5 is much more active than conventional ZSM-5 in catalytic cracking of bulky molecules (1, 3, 5-tri-isopropylbenzene). Moreover, mesoporous ZSM-5 zeolite exhibited high hydrothermally stability.We develop some kinds of facile, low cost and efficient routes to synthesis of mesoporous zeolites. These mesoporous zeolites have a large amount of mesopores and not only inherit excellent acidity and hydrothermal stability, but also improve the adsorption and diffusion of organic molecules. These mesoporous zeolite materials is much more effective and active in some different catalysis than conventional zeolites.更多还原