UNS:New strategies for ultra-thin sub-10 nm thick zeolitic imidazolate framework membranes with tunable molecular sieving properties

Jeong 151530德克萨斯工程实验站从不需要的化学品中分离出需要的化学品对化学和石化工业来说是至关重要的。传统的分离技术，包括蒸馏和冷凝，都是高能耗的。由于现有技术的膜材料的限制，不存在用于分离工业上重要的烃气体的市售膜。新型分子筛（即，具有明确的分子级孔和通道的材料）已经被探索作为膜材料。拟议的工作旨在开发创新的新方法：1）通过使分子筛膜非常有效来降低膜的成本; 2）使筛孔尺寸易于调节，以分离感兴趣的气体混合物。本文提出的全新策略有望产生一系列分子筛材料，其筛尺寸经过微调，可用于工业上感兴趣的气体混合物的定制分离。提出的努力的目标是开发新的方法来制造超薄亚10纳米厚的沸石咪唑骨架（ZIF）膜，以及不断调整其分子筛性能的气体混合物的分离感兴趣。沸石咪唑骨架（ZIF）是金属有机骨架（MOF）的一个子类，主要由于其超微孔（小于5 μ m的孔）和其不寻常的热/化学稳定性而在气体分离中提供独特的机会。为了解决上述基本材料限制以及加工挑战，PI提出开发新策略，以实现1）超薄ZIF膜的合成和2）控制其分子筛性能，用于感兴趣的气体混合物的定制分离。所提出的战略将是真正的变革，因为它们能够制备高效和多产的分子筛膜，有可能取代目前的高能耗分离工艺，从而显著降低能耗。参与该项目的学生将接受从材料合成/表征到膜科学和技术等多学科领域的培训。

Jeong151530Texas Engineering Exp StaSeparations of desired chemicals from undesired ones are critically important for chemical and petrochemical industries. Conventional separation technologies, including distillation and condensation, are highly energy intensive. Due to the limitations of the state-of-the-art membrane materials, there are no commercially available membranes for the separation of industrially important hydrocarbon gases. Novel molecular sieves (i.e., materials with well-defined molecular-scale pores and channels) have been explored as membrane materials. The proposed work intends to develop innovative new approaches 1) to reduce the cost of membranes by making molecular sieving membranes very efficient and 2) to make the sieve size readily adjustable for the separation of gas mixtures of interest. The completely new strategies proposed here are expected to lead to a serious of molecular sieving materials with their sieve sizes finely-tuned for the custom separations of gas mixtures of industrial interest. The goal of the proposed effort is to develop new approaches to fabricate ultra-thin sub-10 nanometer thick zeolitic imidazolate framework (ZIF) membranes as well as to continuously tailor their molecular sieving properties for the separations of gas mixtures of interest. Zeolitic imidazolate frameworks (ZIFs), a sub-class of metal-organic frameworks (MOFs), offer unique opportunities in gas separations primarily due to their ultra-micropores (pores smaller than 5 Å) and their unusual thermal/chemical stabilities. To address the fundamental materials limitations as well as the processing challenges mentioned above, the PI proposes to develop new strategies that enable 1) the synthesis of ultra-thin ZIF membranes and 2) the control of their molecular sieving properties for the custom separations of gas mixtures of interest. The proposed strategies will be truly transformative in that they enable the preparation of highly efficient and productive molecular sieving membranes, potentially replacing highly energy-intensive current separation processes, thereby significantly reducing energy consumption. The students involved in this project will be trained in multi-disciplinary areas ranging from material synthesis/characterization to membrane science and technologies.