Oil Photooxidation by Sunlight: Role of Reactive Species in the Transformation of Saturated and Aromatic Hydrocarbons

在美国国家科学基金会化学部环境化学科学项目的支持下，毕格罗海洋科学实验室的Christoph Aeppli将研究石油碳氢化合物在阳光下转化的机制。这是相关的，因为光氧化会影响海洋泄漏后石油的命运，从而从根本上改变石油残留物的性质、成分和环境命运。本项目将通过进行一系列的实验室辐照实验，提高对石油光化学机理的认识。该项目预计将提供的知识和数据将改善溢油风险和损害评估。该项目还将培养一名博士后研究员和本科生。此外，该项目的结果和方法将在本科课程中实施，并将通过外展计划向更广泛的社区传播该项目的成果。阐明饱和化合物降解的相关途径是具有多重共存竞争途径的复杂混合油中具有挑战性的。这个项目将使用逐步的方法来处理具有三个复杂级别的系统。首先，基本的机械问题将首先用一种由明确定义的碳氢化合物混合物组成的模型油来解决。其次，将使用天然存在于石油中的敏化剂和猝灭剂对这些模型化合物进行各种光化学途径的系统测试。最后，将所获得的知识应用于复杂的石油混合物中发生的复杂过程，目的是构建石油中各种饱和烃和芳烃的相关石油光降解过程的一般概念机制。本项目将采用基于二维气相色谱的创新方法对石油降解进行全面量化，并将开发定量方法来测量石油光产物的形成。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。

With support from the Environmental Chemical Sciences Program in the Division of Chemistry at NSF, Christoph Aeppli at the Bigelow Laboratory for Ocean Sciences will investigate the mechanism of sunlight-mediated transformation of oil hydrocarbons. This is relevant since photooxidation affects the fate of oil after marine spills, thereby fundamentally altering the properties, composition, and environmental fate of oil residues. This project will improve the mechanistic understanding of oil photochemistry by conducting a series of laboratory irradiation experiments. The knowledge and data expected from this project will improve oil spill risk and damage assessment. This project will also train a postdoctoral researcher and undergraduate students. Furthermore, results and methods from this project will be implemented in undergraduate coursework, and outcomes of this project will be communicated to the broader community through outreach programs.To elucidate the relevant pathway for the degradation of saturated compounds is challenging in the complex mixture of oil with multiple co-occurring competing pathways. This project will use a step-wise approach with systems that have three levels of complexity. First, basic mechanist questions will first be addressed using a model oil consisting of a well-defined mixture of hydrocarbons. Second, various photochemical pathways will be systematically tested on these model compounds using sensitizers and quenchers naturally occurring in petroleum. Lastly, the gained knowledge will then be applied to the complex processes occurring in the complex mixture of petroleum, with the aim to construct a general conceptual mechanism of relevant oil photodegradation processes of the various saturated and aromatic hydrocarbons in oil. This project will employ an innovative method based on two-dimensional gas chromatography for the comprehensive quantification of oil degradation and will develop quantitative methods to measure the formation of oil photoproducts.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.