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

9708406皮特斯本项目旨在研究控制多环芳烃(PAHs)混合物在受NAPL污染的土壤中行为的化学、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有关。这些污染物通常以非水相液体(NAPL)的形式存在。对于更大范围和较长时期内这些污染物的影响，对基本机制和全面的成分模拟方法的清楚理解是至关重要的。该项目的具体目标是：(I)深入了解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；(Ii)将NAPL污染系统中的生物降解率与控制生物有效性的热力学相平衡和溶解动力学过程联系起来；(Iii)构建一个完整的多环芳烃在NAPL污染土壤中行为的数学模型，并通过使用PAH-NAPL污染土壤的实验来验证模型公式。实验研究旨在探索多环芳烃的溶解与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条件下是否存在底物相互作用。一个目的是确定从单一底物实验中推断的动力学参数可以在多大程度上与捕捉底物相互作用效应的数学公式结合使用，以描述具有多个多环芳烃底物的系统中发生的事情。这项工作的一个新方面是使用合成的NAPL作为有机液体的模型来模拟煤焦油等多组分污染物，这允许在实验设计和分析表征中进行控制。

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.