Collaborative Research: Experimental and Computational Studies of the Role of Effluent Organic Matter in the Sensitized Transformation of Organic Contaminants

1434148 Arnold 1434313 Latch合作研究：废水有机物在有机污染物敏化转化中作用的实验和计算研究废水有机物（排放到环境中的处理废水中所含的有机物）在微污染物光化学处理中的作用相对未被探索。该项目的总体目标是评估水生污染物的光化学，特别是侧重于测量光化学产生的活性中间产物的生产和淬灭从污水有机物和预测微污染物的速率常数使用计算化学技术。本研究的创新之处在于：1）关注具有特定功能基团的易受间接光解影响的水生污染物; 2）并排比较废水有机物和天然有机物的光化学反应性中间产物的产生/猝灭; 3）光化学反应性中间产物的产生/猝灭与有机物性质的关系;以及4）使用计算化学来预测与光化学产生的反应性中间体的反应性，评估影响反应性的污染物中的具体结构细节，以及区分哪些化合物类别在通过间接光解处理方面值得关注。这些目标将通过一个主要研究机构（明尼苏达大学; UMN）和一个本科院校（西雅图大学; SU）之间的合作，通过现场采样，实验室实验和计算研究相结合来实现。该项目强调研究作为本科学习经验的重要组成部分，并已被设计为有一个主要的，从本科研究人员的实质性贡献。PI将继续招募女性，少数民族和第一代大学生加入他们的研究小组，从而扩大他们对科学界的影响。SU和UMN之间的关系将建立这两个机构之间的联系，科学和工程。这项工作的一个主要动力是，污水处理厂下游的沃茨中的有机物和微污染物是共存的，它的作用被假设，污水中的有机物施加实质性的控制这些污染物的命运。光化学半衰期的一系列污染物的作用的废水有机物的解决方案将被测量和相关的光化学产生的活性中间体从分子探针和淬灭实验确定的稳态浓度。通过这种方式，将开发控制从废水处理厂排放的污染物的命运的光化学过程的理解和作用的污染物转化中的废水有机物的作用。此外，废水中的有机物在淬灭光化学产生的活性中间体和其作为抗氧化剂的作用将得到阐明。计算化学研究将导致新的预测工具和对潜在反应机制的洞察。因此，这项工作的实验和计算结果将是至关重要的污染物的命运和预测污染物在污水为主的表面沃茨的反应。关于光化学产生的活性中间体在受有机物影响的沃茨中的作用的信息也与病原体灭活和碳/养分循环有关，使得更广泛的科学界对结果感兴趣。

1434148Arnold1434313LatchCollaborative Research: Experimental and Computational Studies of the Role of Effluent Organic Matter in the Sensitized Transformation of Organic ContaminantsThe role of effluent organic matter (organic matter contained in treated wastewater that is discharged to the environment) in the photochemical processing of microcontaminants is relatively unexplored. The overall objective of this project is to evaluate the photochemistry of aquatic pollutants, specifically focusing on the measurement of photochemically produced reactive intermediate production and quenching from effluent organic matter and the prediction of micropollutant rate constants using computational chemistry techniques. The innovative aspects of the proposed research are: 1) the focus on aquatic contaminants with specific functional groups susceptible to indirect photolysis; 2) the side-by-side comparison of photochemically produced reactive intermediate production/quenching from effluent organic matter and from natural organic matter; 3) the relation of photochemically produced reactive intermediate production/quenching by organic matter properties; and 4) the use of computational chemistry to predict reactivity with photochemically produced reactive intermediates, evaluate specific structural details in contaminants that influence reactivity, and distinguish which compound classes merit attention with regards to processing via indirect photolysis. The goals will be met through a combination of field sampling, laboratory experiments, and computational studies via collaboration between a major research institution (University of Minnesota; UMN) and an undergraduate institution (Seattle University; SU). The project emphasizes research as an important component of the undergraduate learning experience and has been designed to have a major, substantive contribution from undergraduate researchers. The PIs will continue to recruit female, minority, and first-generation college students into their research groups, thus broadening their impact on the scientific community. The relationship between SU and the UMN will establish connections between these two institutions and between science and engineering.A major impetus for this work is that effluent organic matter and micropollutants are co-located in the waters downstream from wastewater treatment plants, and it is hypothesized that the role of effluent organic matter exerts substantial control over the fate of these contaminants. Photochemical half-lives for a series of contaminants in role of effluent organic matter solutions will be measured and related to the steady-state concentrations of photochemically produced reactive intermediates determined from molecular probe and quenching experiments. In this way, an understanding of the photochemical processes controlling the fate of contaminants emanating from wastewater treatment plants and the role of role of effluent organic matter in contaminant transformations will be developed. Additionally, the role of effluent organic matter plays in quenching photochemically produced reactive intermediates and its role as an antioxidant will be elucidated. The computational chemistry studies will lead to new predictive tools and insights into potential reaction mechanisms. Thus, the experimental and computational findings of this work will be critical in modeling pollutant fate and predicting contaminant reactivity in effluent-dominated surface waters. Information regarding photochemically produced reactive intermediates in role of effluent organic matter -impacted waters is also relevant to pathogen inactivation and carbon/nutrient cycling, making the results of interest to the broader scientific community.