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首页> 外文学位 >Molecular sieve films: New synthesis methods for improving the performance of zeolite ZSM-5 membranes.
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Molecular sieve films: New synthesis methods for improving the performance of zeolite ZSM-5 membranes.

机译：分子筛膜：改善ZSM-5沸石膜性能的新合成方法。

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摘要

The separation performance of MFI type of zeolite membranes for gas and vapor permeation has been improved in this dissertation in several ways.; In the h0h-oriented membranes, defects were sealed by a sol-gel technique, while in the c-oriented MFI membranes, defects could be sealed in situ by introducing a third strongly adsorbing species in the feed stream. In both cases, the selectivity for separation of xylene isomers was greatly improved. However, the concomitant decrease in permeance indicated that the membrane performance was only partially improved by these methods.; A novel seeded growth method was proposed which allowed us to fabricate the first functional b-oriented ZSM-5 membranes with quality good enough to demonstrate separation of mixtures mainly based on molecular sieving effects. Membrane microstructure was optimized in this seeded growth process to be thin, less defective and b-oriented by strategies such as the use of asymmetric supports, oriented seed monolayers and appropriate structure directing agents. Although the process was proposed mainly for MFI type of membranes, it is anticipated that those idea can be extended to the preparation of other types of zeolite membranes.; The microstructurally optimized b-oriented ZSM-5 membrane was applied for the separation of several close-boiling hydrocarbon mixtures, such as xylene isomers, benzene/cyclohexane, and benzene/2,2-dimethylbutane. Significant improvement in both permeance and separation factor was achieved compared to the results reported in the literature.
机译：本文以多种方式提高了MFI型分子筛膜对气体和蒸汽的渗透性能。在h0h取向的膜中，缺陷通过溶胶-凝胶技术被密封，而在c取向的MFI膜中，可以通过在进料流中引入第三种强吸附物质来原位密封缺陷。在这两种情况下，分离二甲苯异构体的选择性都大大提高了。然而，伴随的渗透性降低表明这些方法仅部分改善了膜性能。提出了一种新颖的种子生长方法，该方法使我们能够制造出质量足以证明主要基于分子筛作用分离混合物的质量良好的功能性b取向ZSM-5膜。通过使用不对称支持物，定向种子单层和合适的结构定向剂等策略，可以在该种子生长过程中将膜微结构优化为薄，缺陷少和b取向。尽管该方法主要是针对MFI型膜提出的，但可以预见，这些想法可以扩展到其他类型沸石膜的制备。经微结构优化的b取向ZSM-5膜用于分离几种紧密沸腾的烃混合物，例如二甲苯异构体，苯/环己烷和苯/ 2,2-二甲基丁烷。与文献报道的结果相比，通透性和分离因子均得到了显着改善。

著录项

  • 作者

    Lai, Zhiping.;

  • 作者单位

    University of Massachusetts Amherst.;

  • 授予单位 University of Massachusetts Amherst.;
  • 学科 Engineering Chemical.
  • 学位 Ph.D.
  • 年度 2003
  • 页码 126 p.
  • 总页数 126
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类 化工过程（物理过程及物理化学过程）;
  • 关键词

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