RUI: Characterizing Pyrolysis and Combustion Pathways for Asphaltene Model Compounds

在这个由化学系化学结构、动力学和机理B项目资助的项目中，里士满大学化学系的Carol Parish教授正在探索油页岩中分子的高温分解机制，油页岩是一种替代燃料来源。该项目位于物理化学、有机化学、物理学和计算机科学的交界处，非常适合各级科学家的教育。教区实验室特别适合为在科学方面代表性不足的学生提供最高水平的教育和培训。本科生和研究生将学习如何应用严格的量子化学方法来描述重要的与能源有关的化学反应。这些研究的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中的重要问题，即油页岩和油砂分子成分高温分解和氧化的潜在分子机制。更具体地说，该项目支持对沥青质中发现的分子的高温分解和燃烧途径的计算研究，以及对所产生的多自由基中间体的表征。沥青质是北美尚未开发的碳氢燃料来源；然而，关于这些沉积物的分子性质的信息是最近才有的，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，单参考方法被用来研究1)萘化合物的燃烧和热解，2)富电子的乙炔部分的电环化可能导致沥青质稠合芳香族核的反应途径，以及3)辛基苯中的氢转移过程。目前正在使用多参考方法来研究1)在这些反应途径上产生的多自由基中间体，如萘和烷基萘自由基以及蒽双自由基，2)杂芳族二自由基的电子耦合和电子激发光谱，这将有助于这些物种的实验表征，3)已知的在噻吩热裂解中产生的线性和二乙烯基硫双自由基，以及4)涉及四种化合物的反应以及通过键耦合在自由基电子相互作用中所起的作用。这一奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的审查标准进行评估，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.