RUI: Characterizing Pyrolysis and Combustion Pathways for Asphaltene Model Compounds

在这个由化学部化学结构、动力学和机理B项目资助的项目中，里士满大学化学系的卡罗尔·帕里什教授正在探索油页岩（一种替代燃料来源）中分子的高温分解机制。本项目处于物理化学、有机化学、物理和计算机科学的交叉点，适合对各级科学家进行教育。教区实验室特别适合为科学领域代表性不足的学生提供最高水平的教育和培训。本科和本科后的学生将学习应用严格的量子化学方法来表征重要的与能量相关的化学反应。这些研究结果将为支持以能源为基础的经济提供基础信息，并直接解决油页岩行业的重要问题；即油页岩和油砂分子组分高温分解氧化的潜在分子机制。更具体地说，该项目支持对沥青质分子的高温分解和燃烧途径进行计算研究，并对所产生的多自由基中间体进行表征。沥青质是北美尚未开发的碳氢化合物燃料来源；然而，关于这些沉积物的分子性质的信息直到最近才得到，对这些物种的反应途径，燃烧效率和反应性知之甚少。在这个项目中，单参考方法将用于研究1)萘化合物的燃烧和热解反应途径，2)富电子乙炔部分的电环化可能导致沥青烯融合芳香族核心，3)辛基苯中的氢转移过程。采用多参考文献的方法研究了萘、烷基萘自由基和蒽二自由基等反应途径产生的多自由基中间体，杂芳二自由基的电子耦合和电子激发光谱，这将有助于这些物质的实验表征。3)已知在噻吩热解过程中产生的线性和二乙烯基砜二自由基；4)涉及四自由基的反应以及通过键偶联在自由基电子相互作用中的作用。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。

In this project, funded by the Chemical Structure, Dynamics & Mechanism B Program of the Chemistry Division, Professor Carol Parish of the Chemistry Department at the University of Richmond is exploring the high temperature decomposition mechanisms of the molecules found in oil shale, an alternative fuel source. The project lies at the interface of physical chemistry, organic chemistry, physics and computer science, and is well suited to the education of scientists at all levels. The Parish laboratory is particularly well-positioned to provide the highest level of education and training for students underrepresented in science. Undergraduate and post-baccalaureate students will learn to apply rigorous quantum chemical methods to the characterization of important energy-related chemical reactions. The results from these studies will provide fundamental information to support an energy-based economy and directly address important problems in the oil shale industry; namely, the underlying molecular mechanisms for high temperature decomposition and oxidation of the molecular constituents of oil shale and oil sands.More specifically, this project supports computational investigations of the high temperature decomposition and combustion pathways for molecules found in asphaltenes, as well as to characterize the polyradical intermediates that are produced. Asphaltenes represent an untapped source of hydrocarbon fuel in North America; however, information about the molecular nature of these deposits has only recently become available and very little is known about the reaction pathways, combustion efficiency and reactivity of these species. In this project, single reference methods are being used to study reaction pathways for 1) combustion and pyrolysis of naphthalenic compounds, 2) electrocyclizations of electron-rich acetylenic moieties that may lead to asphaltene fused aromatic cores and 3) hydrogen transfer processes in octylbenzyne. Multi-reference methods are being used to study 1) polyradical intermediates produced along those reaction pathways such as naphthalene and alkyl naphthalene radicals and the anthracene diradicals, 2) electron coupling and electronic excitation spectra for heteroaromatic diradicals that will aid in the experimental characterization of these species, 3) linear and divinylsulfane diradicals known to be produced in the pyrolysis of thiophene and 4) reactions involving tetraradicals and the role that through-bond coupling plays in radical electron interaction.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.