Linking Thermodynamics to Pollutant Reduction Rates by Fe(II) Bound to Iron Oxides

将热力学与 Fe(II) 与氧化铁结合的污染物减少率联系起来

• 批准号: 1807703
• 负责人: Christopher Gorski
• 金额: $ 34.58万
• 依托单位: Pennsylvania State Univ University Park
• 依托单位国家: 美国
• 项目类别: Continuing Grant
• 财政年份: 2018
• 资助国家: 美国
• 起止时间: 2018-08-15 至 2022-01-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=1807703&HistoricalAwards=false
• 关键词: Linking; Thermodynamics; Pollutant; Reduction; Rates

This award from the Environmental Chemical Sciences Program in the Division of Chemistry supports research by Prof. Christopher Gorski at Pennsylvania State University. The goal of this project is to improve public access to clean water. The majority of drinking water in the U.S. comes from groundwater aquifers. In the U.S., over 126,000 groundwater aquifers contain toxic chemicals. This research aims to understand how toxic chemicals transform in groundwater systems over time. The work looks at how the composition of water affects the transformations. The work also develops a new teaching program for grade 6-12 young women. The teaching program aims to teach young women about groundwater and chemistry. This work aims to mechanistically elucidate why pollutant reduction rates by Fe(II) bound to iron oxide minerals are highly sensitive to changes in solution chemistry and the presence of iron oxide nanoparticles. Many classes of environmental pollutants undergo reductive transformations in groundwater coupled to the oxidation of oxide-bound Fe(II). These transformations significantly alter a pollutant's toxicity, solubility, and/or bioavailability, and therefore they must be taken into account in risk assessments and remediation efforts. The rates of these reactions are highly variable among studies. Reported reaction rate constants varying by over six orders of magnitude for commonly studied pollutants. Models based on thermodynamic parameters can often explain trends among measured pollutant reduction rates in simple water chemistries. However, they fail to describe datasets collected with more complex water chemistries relevant to real groundwater systems, limiting their practical use. To address this issue, this project tests several working hypotheses previously proposed in the literature to elucidate the mechanisms responsible for changes in pollutant reduction rates when iron oxide nanoparticles, carbonate, and/or natural organic matter are present.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.

该化学系环境化学科学计划的奖项支持宾夕法尼亚州立大学克里斯托弗·戈尔斯基教授的研究。该项目的目的是改善公众获得清洁水的机会。美国大多数饮用水都来自地下水含水层。在美国，超过126,000多个地下水含水层含有有毒化学物质。这项研究旨在了解有毒化学物质如何随着时间的流逝而在地下水系统中转变。这项工作着眼于水的成分如何影响转化。这项工作还为6至12年级的年轻女性开发了一项新的教学计划。该教学计划旨在教年轻女性有关地下水和化学的知识。 这项工作旨在从机械上阐明为什么与氧化铁矿物结合的Fe（II）的污染物还原率对溶液化学变化和氧化铁纳米颗粒的存在高度敏感。许多类别的环境污染物在地下水中经历了还原性转化，并结合了氧化物结合的Fe（II）的氧化。这些转变会大大改变污染物的毒性，溶解性和/或生物利用度，因此必须在风险评估和补救工作中考虑它们。这些反应的速率在研究之间是高度可变的。报告的反应速率常数因常用污染物而变化六个数量级以上。基于热力学参数的模型通常可以解释简单水化学中测得的污染物还原率之间的趋势。但是，他们无法描述与与实际地下水系统相关的更复杂的水化学分配收集的数据集，从而限制了它们的实际使用。为了解决这个问题，该项目测试了文献中先前提出的几种工作假设，以阐明当前存在氧化铁纳米颗粒，碳酸盐和/或自然有机物时，导致污染物降低率变化的机制。此奖项反映了NSF的法定任务和法定任务和法定任务。使用基金会的知识分子优点和更广泛的审查标准，通过评估被认为值得支持。