PECASE: Zeolitic Imidazolate Framework Membranes. Novel Materials for Carbon Dioxide Capture.

从轻质气体中分离二氧化碳是一个非常重要的环境和能源问题。最先进的二氧化碳净化工艺使用胺吸附，这是一种复杂且昂贵的方法。膜分离技术的成本要低得多，需要的能源消耗也更少。尽管聚合物膜和沸石膜可以将二氧化碳从轻质气体中分离出来，但开发性能优异的混合气体分离膜需要具有与聚合物和沸石完全不同的结构、组成、吸附和传输性能的新型材料。在这方面，分子筛咪唑骨架(ZIF)是金属有机骨架的一个子类，是一种新型的结晶型多孔材料，具有均匀的微孔、高的比表面积以及优异的热稳定性和化学稳定性，使其成为分子分离的理想材料。这项提议旨在展示ZIF作为从轻质气体中分离二氧化碳的膜的潜力。这份职业计划的核心思想是建立一个坚实的基础科学计划，从而合理设计一系列新型的膜，这些膜由分子筛咪唑骨架组成，可以展示从轻气中提纯二氧化碳和其他重要功能气体分离的高分离性能。具体的研究目标是：1)合理设计一类用于从轻气中净化二氧化碳的新型分子筛咪唑骨架(ZIF)膜；2)开发简便的化学合成策略，合理地改变ZIF膜的孔结构和功能；3)阐明和理解控制前体溶液转化为沸石咪唑骨架相的基本形成机理；以及4)建立ZIF膜在相关功能气体分离中的基本结构/分离关系。如果成功，这项职业发展计划将确立新型自组装和合成概念的可行性，作为一种广泛的功能性分子筛咪唑骨架膜的一般方法，这些膜具有可调的结构、表面化学和孔隙率，用于相关工业气体分离，包括从天然气和烟道气中捕获二氧化碳。这将代表着在合理设计一类金属有机骨架膜以及从根本上理解其结构/分离关系方面的重要进展。这项提议的一个平行目标是有效地将拟议的研究活动与教育和推广计划结合起来，以在本科生、研究生和社区层面提供重要的教育机会。拟议职业生涯计划的教育范围包括关于纳米功能材料分子工程的双级课程、将未被充分代表的群体纳入本科教育、国际合作、招募少数族裔进行研究生学习以及为高中教师开设的短期课程。该项目的成果将通过期刊出版物、会议报告和技术研讨会向科学界传播，并将在PI讲授的课程材料讲座中实施，使对膜科学、分离过程和先进材料感兴趣的学生受益。教育活动已经产生了一个由资金资助的国际合作，作为招收少数族裔学生的平台；少数族裔本科生参与PI实验室的研究；为路易斯维尔大学化学工程系的博士项目招收墨西哥学生，并建立了一个名为HISPAIRE(对工程必修课感兴趣的拉美裔美国人)的方案，旨在招收拉美裔和拉丁裔学生。

The separation of CO2 from light gases is a very important environmental and energy issue. The state-of-the-art process for the purification of CO2 uses amine adsorption, which is a complex, and costly approach. Membrane separation technology is far less expensive and requires less energy consumption. Although polymeric and zeolite membranes can separate CO2 from light gases, the development of superior performance membranes for gas mixture separations requires novel materials with fundamentally different structural, compositional, adsorption and transport properties than those of polymers and zeolites. In this respect, zeolitic imidazolate frameworks (ZIFs) a subclass of metal organic frameworks, have emerged as a novel type of crystalline porous materials which combine highly desirable properties, such as uniform micropores, high surface areas, and exceptional thermal and chemical stability, making them ideal candidates for molecular separations. This proposal aims at demonstrating the potential of ZIFs as membranes for the separation of CO2 from light gases. The central intellectual thrust of this career proposal is to establish a solid fundamental science program leading to the rational design of a novel family of membranes, composed of zeolitic imidazolate frameworks which offer the possibility of demonstrating high separation performance for carbon dioxide purification from light gases, and other important functional gas separations. The specific research objectives are: 1)Rational design of a novel family of zeolitic imidazolate framework (ZIF) membranes for CO2 purification from light gases; 2)Develop facile chemical synthesis strategies to rationally modify the pore structure and functionality of the ZIF membranes; 3)Elucidate and understand the basic formation mechanisms governing the transformation of precursor solutions into zeolitic imidazolate framework phases; and 4)Establish the fundamental structure/separation relationships of ZIF membranes in relevant functional gas separations such as CO2/CH4 and CO2/N2. If successful, this career development plan will establish the viability of novel self-assembly and synthesis concepts as general approaches for a broad range of functional zeolitic imidazolate framework membranes with tunable architectures, surface chemistry, and porosities for applications in relevant industrial gas separations, including CO2 capture from natural gas and flue gas. It will represent an important advance in the rational design of a subclass of metal organic framework membranes and in fundamental understanding of its structure/separation relationships. A parallel objective of this proposal is to effectively integrate the proposed research activities with education and outreach programs to provide significant educational opportunities at the undergraduate, graduate and community levels. The educational outreach of the proposed career plan spans from a dual level course on molecular engineering of functional nanoporous materials, inclusion of underrepresented groups in undergraduate education, international collaboration, recruitment of minorities for graduate studies, and a short course for high school teachers. The results of this project will be disseminated to the scientific community through journal publications, conference presentations and technical seminars, and will be implemented in course material lectures taught by the PI to benefit the student body interested in membrane science, separation processes and advanced materials. The educational activities have already resulted in a funded international collaboration as a platform for minority student recruitment; undergraduate minority student research participation in the PI laboratory; recruitment of Mexican students for the PhD program in Chemical Engineering Department at University of Louisville and the establishment of a program called HISPAIRE (Hispanics with Interest in the Requisites for Engineering), aimed at recruiting Hispanic and Latino students.