Development of New Materials and Methods for Effective, Selective, and Energy-efficient Olefin/Paraffin Separation and Ethylene Detection

重要的化学原料包括一组称为烯烃的分子，这些分子含有碳-碳双键。烯烃用于制造许多重要的塑料，包括用于制造聚乙烯的乙烯;用于制造聚丙烯的丙烯;以及其他几种。烯烃是在原油精炼过程中产生的。然而，它们总是作为烯烃和其他石油组分的复杂混合物获得。为了获得纯烯烃，使用能量密集型蒸馏工艺分离原油混合物。目前，仅乙烯和丙烯的提纯就占世界总能耗的约0.3%。一种更有效的烯烃分离技术将是非常有益的。为此，德克萨斯大学阿灵顿分校（UTA）的Rasika Dias博士得到了化学合成计划的支持，以开发能够在室温和压力下分离烯烃的金属化合物。一般方法制备结合特定烯烃的铜化合物，并且可以被诱导以靶向方式释放烯烃。这种行为可用于烯烃的低能量纯化。作为辅助的努力，铜和相关的银化合物进行了修改，以检测烯烃。这不仅对监测工业环境很重要，而且对一些水果和花卉业也很重要，因为乙烯会导致水果（如香蕉）成熟和花卉退化。该项目将研究整合到本科生，研究生和博士后的教育经验中，并为他们的生产性职业做好准备。迪亚斯教授计划从传统上代表性不足的群体，包括麦克奈尔和LSAMP计划招收学生，在他的实验室提供研究机会。还计划开展高中和社区学院学生辅导活动。迪亚斯教授在UTA组织了一个研讨会，邀请助理教授和博士后见面并分享他们的研究成果。 他还组织了一个关于X射线晶体学的研讨会，以使区域晶体学家受益，并利用UTA天文馆的设施来教育和激发年轻观众（包括pre-K）在science.In这个项目中，铜和银配合物的多齿吡唑配体的合成和他们的能力，选择性和可逆地结合乙烯，丙烯和丁烷进行了评估。进行了系统的研究，以了解如何通过修改的支持配体的烯烃结合的整体热量可以管理。 本研究的目标是设计促进烯烃-烷烃分离的化合物。 第二个重点集中在传感器检测乙烯的发展。 在这项工作中，制备了一系列发光铜和银吡唑配合物，它们在暴露于烯烃时产生光信号。 总的来说，该项目研究了具有不稳定金属-配体相互作用的后期d-区络合物的结构，成键和反应性。 为该项目做出贡献的学生将获得合成、现代表征技术和批判性思维方面的宝贵经验。该奖项反映了NSF的法定使命，并被认为值得通过使用基金会的智力价值和更广泛的影响审查标准进行评估来支持。

Important chemical feedstocks include a group of molecules called alkenes, molecules that contain carbon-carbon double bonds. The alkenes are used in the manufacture of many important plastics and include ethylene, which is used to make polyethylene; propylene, which is used to make polypropylene; and a several others. The alkenes are produced during the refining of crude oil. However, they are always obtained as complex mixtures of alkenes and other petroleum components. In order to obtain pure alkenes, crude oil mixtures are separated using an energy-intensive distillation process. Presently, ethylene and propylene purification alone accounts for about 0.3% of the world’s total energy consumption. A more a efficient separation technique for alkenes would be of great benefit. Toward this end, Dr. Rasika Dias, University of Texas at Arlington (UTA), is supported by the Chemical Synthesis Program to develop metal compounds that are capable of separating alkenes at room temperature and pressure. The general method prepares copper compounds that bind specific alkenes and can be induced to release the alkene in a targeted way. This behavior may be used for the low energy purification of alkenes. As an ancillary effort, the copper and related silver compounds are modified to detect alkenes. This is important not only to monitor industrial environments, but also to a number of fruit and flower industries as ethylene induces the ripening of fruit (such as bananas)and the degradation of flowers. This project integrates research into the educational experience for undergraduate, graduate, and postdoctoral students, and prepares them for productive careers physical science. Professor Dias plans to recruit students from traditionally underrepresented groups including McNair and LSAMP programs, offering research opportunities in his laboratory. High-school and Community College student mentoring activities are also planned. Professor Dias organizes a symposium at UTA inviting Assistant Professors and Postdoctoral Fellows to meet and share their research findings. He also organizes a workshop on X-ray crystallography to benefit area crystallographers and utilizes the UTA Planetarium facilities to educate and excite young audiences (including pre-K) in science.In this project, copper and silver complexes of multi-dentate pyrazolate ligands are synthesized and their abilities to selectively and reversibly bind ethylene, propylene, and butane are evaluated. A systematic study is undertaken to discern how the overall heat of the olefin-binding can be managed through modification of the supporting ligands. The goal of this research is to design compounds that facilitate olefin-paraffin separations. A second focus concentrates on the development of sensors to detect ethylene. In this effort, a family of luminescent copper and silver pyrazolate complexes that produce optical signals upon exposure to olefins are prepared. Overall, the project investigates the structure, bonding, and reactivity of late d-block complexes with labile metal-ligand interactions. Students contributing to this project will gain valuable experience in synthesis, modern characterization techniques, and critical thinking.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.