RUI: Adsorption and Surface Mediated Photo-Degradation Rate of Contaminants on Colloidal Natural Organic Matter

RUI：污染物在胶体天然有机物上的吸附和表面介导的光降解率

基本信息

批准号：
1808468
负责人：
Mahamud Subir
金额：
$ 24.84万
依托单位：
Ball State University
依托单位国家：
美国
项目类别：
Standard Grant
财政年份：
2018
资助国家：
美国
起止时间：
2018-07-01 至 2023-06-30
项目状态：
已结题

来源：
https://www.nsf.gov/awardsearch/showAward?AWD_ID=1808468&HistoricalAwards=false
关键词：
RUI Adsorption Surface Mediated Photo

项目摘要

With support from the Environmental Chemical Sciences Program of the Chemistry Division, Dr. Mahamud Subir and his students at Ball State University explore the influence of Natural Organic Matter (NOM) on the transport and fate of emerging contaminants (ECs). ECs, such as pharmaceuticals and endocrine disruptors, are commonly detected in aquatic environments. NOM are particles suspended in environmental waters that consist of carbon-based molecules. NOM plays a role in aquatic pollutant distribution and transformation, but exactly how and to what extent remains unclear. This study focuses on finding the effect of NOM particle size and surface constituents on the uptake and photochemical breakdown of organic contaminants. The projects provide undergraduate students with a unique opportunity to perform hands-on experiments. The study creates information about binding strength of the contaminant molecules and NOM, and the rates of reactions that are mediated by the NOM surfaces. These findings help to explain the impact of ECs on our ecosystem and our health. This study uses both traditional and advanced laser spectroscopic tools in the areas of nano-, surface, and environmental chemistry. Second Harmonic Generation (SHG) and other analysis techniques isolate the surface effect from the bulk solution phase photochemistry of organic pollutants. The project develops model colloidal NOM using humic substances of distinct composition. The binding affinities of various ECs to the model NOM surfaces are measured. The rate of photolysis of both chemi- and physi-sorbed molecules at the NOM-aqueous interface is determined. In addition, the project investigates the influence of NOM size, solution acidity, and presence of reactive hydroxyl radicals on the processes of interest. These results are expected to yield an extensive catalogue of adsorption equilibrium and photo-kinetic parameters. They also provide fundamental insight into the nature of specific EC-NOM surface interactions. This knowledge can potentially assist in developing remediation methodologies.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.

在化学系环境化学科学项目的支持下，鲍尔州立大学的 Mahamud Subir 博士和他的学生探索天然有机物 (NOM) 对新兴污染物 (EC) 的迁移和归宿的影响。 EC，例如药物和内分泌干扰物，通常在水生环境中检测到。 NOM 是悬浮在环境水中的由碳基分子组成的颗粒。 NOM 在水生污染物的分布和转化中发挥着作用，但具体如何发挥作用以及作用程度如何仍不清楚。本研究的重点是寻找 NOM 粒径和表面成分对有机污染物的吸收和光化学分解的影响。这些项目为本科生提供了进行实践实验的独特机会。该研究创建了有关污染物分子和 NOM 的结合强度以及 NOM 表面介导的反应速率的信息。这些发现有助于解释 EC 对我们的生态系统和健康的影响。这项研究在纳米、表面和环境化学领域使用了传统和先进的激光光谱工具。二次谐波发生 (SHG) 和其他分析技术将表面效应与有机污染物的本体溶液相光化学隔离开来。该项目使用不同成分的腐殖质开发模型胶体 NOM。测量各种 EC 与模型 NOM 表面的结合亲和力。测定 NOM-水界面处化学和物理吸附分子的光解速率。此外，该项目还研究了 NOM 尺寸、溶液酸度和活性羟基自由基的存在对相关过程的影响。这些结果预计将产生广泛的吸附平衡和光动力学参数目录。它们还提供了对特定 EC-NOM 表面相互作用性质的基本见解。这些知识可能有助于开发补救方法。该奖项反映了 NSF 的法定使命，并且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。