Collaborative Research: (EGB) Multisubstrate Biodegradation Kinetics of Polycyclic Aromatic Hydrocarbons (PAHs) in NAPL-Contaminated Soils

小行星9708406 本研究旨在探讨多环芳香族碳氢化合物（PAHs）混合物在NAPL污染土壤中的化学、物理和微生物过程。 多环芳烃是一类重要的有机污染物，通常与煤焦油、杂酚油和柴油等多组分有机污染物相关。 这些污染物通常以非水相液体（NAPL）的形式存在。 对潜在机制的清晰理解和全面的成分建模方法对于了解这些污染物在更大范围内和长时间内的影响至关重要。 该项目的具体目标是：（I）获得关于多环芳烃在单一和多基质系统中的相对生物降解性和基质相互作用的见解，（ii）将NAPL污染系统中的生物降解速率与控制生物利用度的热力学相平衡和溶解动力学过程联系起来，以及（iii）构建NAPL污染土壤中PAH行为的综合数学模型，并通过PAH-NAPL污染土壤的实验验证模型公式。 实验研究的目的是探索多环芳烃的溶解和生物降解的相互关系，并观察在不同的初始底物浓度和比例的条件下，底物相互作用的存在或不存在。 一个目的是确定在何种程度上从唯一的基板实验推断的动力学参数可以结合使用的数学公式，捕捉基板相互作用的影响，描述发生在一个系统中的多个PAH基板。 这项工作的一个新的方面是使用合成NAPLs作为模型有机液体来模拟多组分污染物，如煤焦油，这允许控制实验设计和分析表征。

9708406 Peters This project is designed to investigate the chemical, physical, and microbiological processes governing the behavior of mixtures of polycyclic aromatic hydrocarbons (PAHs) in NAPL-contaminated soils. PAHs are an important class of organic pollutants that are commonly associated with multicomponent organic contaminants such as coal tar, creosote, and diesel fuel. These contaminants commonly exist as non-aqueous phase liquids (NAPLs). A clear understanding of underlying mechanisms and a comprehensive compositional modeling approach is essential to understanding the impacts of these contaminants on a larger scale and over a long time periods. The specific objectives of this project are: (I) to gain insights about relative biodegradabilities and substrate interactions of PAHs in sole and multi-substrate systems, (ii) to relate biodegradation rates in NAPL contaminated systems to the thermodynamic phase equilibrium and dissolution kinetic processes governing bioavailability, and (iii) to construct an integrated mathematical model of PAH behavior in NAPL-contaminated soils and to validate model formulation through experimentation using PAH-NAPL-contaminated soils. Experimental studies are designed to explore the interrelation of PAH dissolution and biodegradation, and to observe the presence or absence of substrate interactions under various conditions of initial substrate concentrations and proportions. One aim is to ascertain the extent to which kinetic parameters inferred from sole substrate experiments can be used in conjunction with a mathematical formulation that captures substrate interaction effects to describe what happens in a system with multiple PAH substrates. A novel aspect of this work is the use of synthetic NAPLs as models organic liquids to simulate multicomponent contaminants such as coal tars, which permits control in experimental design and analytical characterization.