Towards High Selectivity MFI Molecular Sieve Membranes through Microstructural Optimization

通过微观结构优化实现高选择性 MFI 分子筛膜

• 批准号: 0091406
• 负责人: Michael Tsapatsis
• 金额: $ 25万
• 依托单位: University of Massachusetts Amherst
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2001
• 资助国家: 美国
• 起止时间: 2001-03-01 至 2004-02-29
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=0091406&HistoricalAwards=false
• 关键词: Towards; Selectivity; MFI; Molecular; Sieve

Proposal No.: CTS-0091406Proposal Type: Investigator InitiatedPrincipal Investigators: Michael Tsapatsis Institution: University of Massachusetts Amherst Towards High Selectivity Molecular Sieve Membranes through MicrostructuralOptimizationThe objective of this project is to relate the microstructure of polycrystalline zeolite films to membrane separation performance. The project involves the study of two classes of films of the same zeolite (high-silica MFI) with distinctly different microstructure, stability and separation performance. These films are prepared by the secondary growth technique. Optical and electron microscopy are combined with X-ray diffraction to unravel the microstructural differences of these films at the nanometer level. The structural information is used to relate these differences to membrane properties likeselectivity and susceptibility to membrane cracking. Approaches for avoiding crackformation and methods for selective crack sealing are being investigated.Zeolites and related molecular sieves are crystalline materials with microporous frameworks capable of filtering molecules at the subnanometer level. The formation of crystalline molecular sieve membranes enables separations of molecules with similar physicochemical properties that are difficult to separate by other methods. As a result,efforts towards zeolite membrane preparation are receiving increasing attention worldwide. Recent advances have resulted in commercialization efforts and suggest new opportunities for applications in gas, liquid and vapor separations. Potential applications include separations of specialty chemicals, hydrocarbon isomers, and permanent gases as well as water/alcohol solutions by pervaporation. In order to sustain the initial success of first-generation zeolite membranes, and to find uses in new processing strategies unattainable with the current membrane technology (e.g., isomerization membrane reactors, chiral separations, etc.), research efforts are required that will combine synthetic innovation with fundamental understanding of the synthesis-microstructure-performanceinterrelationships. This work emphasizes the microstructure-performance issues. Its outcome will contribute to the development of rational rather than trial-and-error strategies for the formation of high performance molecular-sieve membranes tailored to specific separation applications.

方案编号： CTS-0091406提案类型：研究者发起主要研究者：Michael Tsapatsis机构：马萨诸塞州阿默斯特大学通过微观结构优化实现高选择性分子筛膜本项目的目的是将多晶沸石膜的微观结构与膜分离性能联系起来。 该项目涉及研究两类具有明显不同微观结构、稳定性和分离性能的相同沸石（高硅MFI）的膜。 这些薄膜是通过二次生长技术制备的。 光学和电子显微镜相结合的X射线衍射解开这些薄膜的微观结构差异在纳米级。结构信息用于将这些差异与膜的特性如选择性和对膜破裂的敏感性联系起来。目前正在研究避免裂纹形成的方法和选择性裂纹密封的方法。沸石和相关分子筛是具有微孔骨架的结晶材料，能够在亚纳米水平过滤分子。结晶分子筛膜的形成使得能够分离具有类似物理化学性质的分子，这些分子难以通过其他方法分离。因此，沸石膜制备的努力在世界范围内受到越来越多的关注。最近的进展导致了商业化的努力，并提出了新的机会，在气体，液体和蒸气分离的应用。潜在的应用包括通过渗透蒸发分离特种化学品、烃异构体和永久性气体以及水/醇溶液。 为了维持第一代沸石膜的初步成功，并发现在当前膜技术无法实现的新加工策略中的用途（例如，异构化膜反应器、手性分离等），需要将联合收割机的合成创新与对合成-微结构-性能相互关系的基本理解相结合的研究努力。 这项工作强调了微观结构-性能问题。它的结果将有助于合理的，而不是试错策略的发展，形成高性能的分子筛膜量身定制的特定分离应用。