ERI: Evaluating Single-Walled Zeolitic Nanotubes for Separation Applications: Adsorption and Transport via Molecular Simulations

化学分离是关键的工业过程，用于从气流中去除二氧化碳和净化饮用水等应用。许多目前的分离方法需要大量的能量，并且仍然存在效率和产量问题。由一种叫做沸石的晶体材料组成的膜已经成功地克服了这些限制。沸石具有规则的纳米级孔隙，可作为分子过滤器。化学合成技术确定了精确的孔径，可以调整到特定的分子分离需要。沸石通常以膜的形式存在，但它们最近被制成了纳米管的形式，产生了一种结构，其中心通道被含有较小孔隙的壁包围。该研究项目将使用分子模拟技术在一系列不同的化学环境中模拟这种新型沸石纳米管结构，评估其增强沸石基分离技术的潜力。模拟结果将产生基础知识，以了解这些多尺度结构的能力，并使分离技术的设计能够利用其独特的几何形状。研究成果将被纳入代顿大学主办的本科热力学课程和高中生夏令营。该项目的教育活动还将向下一代化学工程师宣传统计数据分析的重要性。本课题的主要目的是通过分子模拟全面表征新合成的沸石纳米管（ZNTs）的吸附和传输行为。沸石是一种很有前途的吸附材料，可用于分离气体混合物、各种有机溶液和用作海水淡化膜。研究任务旨在评估ZNT复制平面沸石行为的能力，以及它们在高维结构（如ZNT阵列）和聚合物膜添加剂中的表现。ZNTs的多尺度特性有望实现压力驱动的流动，而过滤则通过沸石壁径向进行。该项目的结果将为使用这些分层结构材料的潜在变革性分离技术的设计提供信息。首席研究员积极参与在代顿大学举办的高中工程夏令营的运作。该项目的结果和计算方法将被纳入夏令营课程，以培养对分离科学的兴趣，并促进统计数据分析在工程中的重要性。类似的教学材料也将用于开发一门新的本科/研究生课程，该课程将使用统计技术设计有效的实验，从而使学生准备好处理现实世界的工程问题。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

Chemical separations are critical industrial processes used in applications such as removing carbon dioxide from gas streams and purifying drinking water. Many current separation approaches require massive amounts of energy and still suffer from efficiency and yield issues. Membranes consisting of a crystalline material called zeolites have successfully overcome some of these limitations. Zeolites have regular, nanoscale pores that act as molecular filters. The chemical synthesis technique determines the exact pore size, which can be tuned to specific molecular separation needs. While zeolites typically take the form of membranes, they have recently been created in a nanotube form, yielding a structure with a central channel enclosed by walls containing smaller pores. This research project will use molecular simulation techniques to model this novel zeolite nanotube structure in a range of different chemical environments, assessing its potential to enhance zeolite-based separation technologies. The simulation results will produce foundational knowledge to understand the capabilities of these multiscale structures and to enable the design of separation techniques that exploit their unique geometry. Research results will be incorporated into undergraduate thermodynamics courses and high school-student summer camps hosted at the University of Dayton. The project’s educational activities will also promote the importance of statistical data analysis among the next generation of chemical engineers. The primary objective of this research project is to comprehensively characterize the adsorption and transport behavior of the newly synthesized zeolite nanotubes (ZNTs) via molecular simulation. Zeolites are promising adsorbent materials for separating gaseous mixtures, various organic solutions, and use as desalination membranes. The research tasks are designed to evaluate the ability of ZNTs to replicate planar zeolite behaviors and how they perform in higher dimensional structures such as ZNT arrays and as additives to polymeric membranes. The ZNTs’ multiscale features are expected to allow for pressure-driven flow, while filtration occurs radially through the zeolitic walls. The project’s results will inform the design of potentially transformative separation technologies using these hierarchically-structured materials. The principal investigator is heavily involved in operating high school-level engineering summer camps hosted at the University of Dayton. This project’s results and computational methods will be incorporated into the summer camp curriculum to build interest in separation sciences and promote the importance of statistical data analysis in engineering. Similar instruction materials will also be used to develop a new undergraduate/graduate course on designing effective experiments using statistical techniques, thus, preparing students to approach real-world engineering problems.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.