Alkali metal based selective combustion catalysts

化学工艺技术的进步将是减少石油化工生产的能源使用和排放足迹的关键。最近的全球化学工业技术路线图将烯烃（聚合物材料的关键分子组成部分）的生产确定为这方面的突出机会。为此，该项目提出了一种将轻烃烷烃转化为烯烃的新工艺方案。该工艺基于串联催化操作，其中烷烃脱氢与选择性氢燃烧（SHC）相结合，与传统的烷烃制烯烃工艺技术相比，降低了能源需求，提高了烯烃产量，减少了温室气体（GHG）排放。技术目标得到了一系列教育和外联活动的支持。该项目探索了一种基于新型非氧化还原活性碱金属配方的催化技术，以选择性地燃烧碳氢化合物混合物中的氢。本研究将系统探讨高温条件下碱金属催化剂的结构和功能演变。该研究旨在了解氧活化和选择性氢燃烧的机制，探测潜在反应的动力学，并最终确定通过选择性氢燃烧实现高效烷烃-烯烃反应的分子特征。科学目标将通过以下方式实现：(i)利用探针分子吸附和反应研究、近环境压力x射线光电子能谱以及衍射和显微镜方法的组合对碱金属催化剂配方进行结构和化学表征；（ii）利用探针分子反应和分子束质谱法鉴定和枚举自由基种类，以确定自由基种类的潜在催化作用。作为这项研究工作的一部分，培训、教育和推广工作将强调科学和工程在为工业制造铺路下一代技术方面的关键作用，并将包括虚拟课外项目、大规模开放在线课程的讲座、本科和研究生水平的培训，以及适合高温反应堆安全运行的实践的开发和传播。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。

Advances in chemical process technology will be key in reducing the energy use and emissions footprint of petrochemical manufacturing. A recent global chemistry industry technology roadmap identified production of olefinic hydrocarbons (key molecular building blocks for polymer materials) as a standout opportunity in this regard. To that end, the project addresses a novel process scheme for converting light hydrocarbon alkanes to olefins. The process is rooted in a tandem catalytic operation in which alkane dehydrogenation is coupled with selective hydrogen combustion (SHC) to decrease the energy demands, increase olefin yield, and decrease greenhouse gas (GHG) emissions compared to conventional alkane-to-olefin process technology. The technical objectives are supported by a range of educational and outreach initiatives.The project explores catalytic technology based on a new class of non-redox-active alkali metal formulations to selectively combust hydrogen in mixtures with hydrocarbon species. This research will systematically probe the structural and functional evolution of the alkali metal catalyst under high temperature conditions. The research aims to develop an understanding of mechanisms of oxygen activation and selective hydrogen combustion, probe kinetics of the underlying reactions, and ultimately determine the molecular characteristics that enable efficient alkane-to-olefin reaction via selective hydrogen combustion. The scientific objectives will be accomplished by (i) structural and chemical characterization of the alkali metal catalyst formulation using a combination of probe molecule adsorption and reaction studies, near ambient pressure X-ray photoelectron spectroscopy, and diffraction and microscopy methods; and (ii) identification and enumeration of radical species using probe molecule reactions and molecular beam mass spectrometry to determine the potential catalytic role of radical species. Training, education, and outreach efforts as part of this research effort will emphasize the key role of science and engineering in paving next generation technologies for industrial manufacturing and will involve virtual after-school programs, lectures in a massive open online course, training at the undergraduate and graduate level, and development and dissemination of practices suited for safe operation of high temperature reactors.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.