Uncovering Mechanisms of PFAS Adsorption by Granular Activated Carbon to Support PFAS Remediation

揭示颗粒活性炭吸附 PFAS 的机制以支持 PFAS 修复

• 批准号: 10337311
• 负责人: Detlef R Knappe
• 金额: $ 9.81万
• 依托单位: NORTH CAROLINA STATE UNIVERSITY RALEIGH
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-02-28 至 2025-01-31
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10337311
• 关键词: Address; Adsorption; Affect; Air; Carbon; Characteristics; Communities; Consumption; Coupled; Data; Development; Diffusion; Dimensions; Effectiveness; Electron energy loss spectroscopy; Environmental Engineering technology; Environmental Health; Environmental Pollution; Environmental Science; Environmental sludge; Equilibrium; Evaluation; Excision; Film; Foundations; Goals; Guidelines; Health; Industrialization; Isotopes; Kinetics; Laboratories; Life; Link; Mass Spectrum Analysis; Microscopy; Modeling; Municipalities; North Carolina; Particle Size; Penetration; Persons; Plants; Poly-fluoroalkyl substances; Preventive; Process; Production; Property; Public Health; Radial; Research; Research Project Grants; Scanning Electron Microscopy; Scanning Tunneling Microscopy; Services; Sewage; Site; Source; Sum; Superfund; Surface; System; Technology; Testing; Time; United States; Universities; X ray spectrometry; aqueous; community engagement; contaminated drinking water; cost; cost effective; design; drinking water; experimental study; exposed human population; improved; innovation; insight; ion mobility; laboratory experiment; landfill; mathematical model; organic contaminant; particle; perfluorooctane sulfonate; perfluorooctanoic acid; pollutant; predictive modeling; programs; remediation; scale up

ABSTRACT (Environmental Science and Engineering) Research Project 4 Project 4 is one of two Environmental Science and Engineering (ESE) Research Projects for the proposed “Center for Environmental and Health Effects of PFAS” being led by North Carolina State University (NC State). The primary goal of the proposed Center is to provide highly relevant data and information to help the Superfund Research Program (SRP) address the growing problem of per- and polyfluoroalkyl substance (PFAS) contamination across the US, including contamination of drinking water sources. PFAS are considered contaminants of emerging concern, and remediation of PFAS-impacted sites is a critical and timely public health challenge. Granular activated carbon (GAC) adsorption is the most widely employed PFAS remediation technology. Although much is known about sorption of organic contaminants by GAC, predicting GAC effectiveness from laboratory data or from fundamental pollutant and GAC properties remains a significant challenge. Our long-term objective is to develop models that predict sorption of organic micropollutants, including PFAS, in GAC treatment systems. A critical barrier to improving existing models is that accessibility of sorption sites inside of GAC particles is not known. An important assumption of current models is that contaminants are uniformly distributed inside of GAC particles at sorption equilibrium. However, direct observations of sorbed contaminants suggest that sorption can occur preferentially near the external sorbent surface. This distinction is significant because it can explain why PFAS sorption capacity increases with decreasing GAC particle size and why laboratory experiments overestimate PFAS removal effectiveness of GAC. Our overarching hypothesis is, therefore, that sorption of PFAS (as well as many other organic pollutants) occurs preferentially in a shell region near the external GAC surface. The shell adsorption hypothesis will be evaluated by (Aim 1) observing and describing intraparticle PFAS distributions at sorption equilibrium and (Aim 2) quantifying and describing PFAS adsorption/desorption kinetics. Using innovative approaches, such as isotope microscopy, we will begin to open the “black box” that GAC still represents and directly observe intraparticle PFAS distributions. We will use information from direct observations in conjunction with results from sorption equilibrium and kinetic experiments to explain our data with a shell adsorption model. We expect that model parameters will be physically meaningful and can be predicted from fundamental sorbent and sorbate properties. Results of this project will support the development of effective sorbents for PFAS removal, the design of (cost-)effective GAC treatment systems for PFAS remediation, and the evaluation of management options for spent GAC.

抽象的 （环境科学与工程）研究项目4 项目 4 是拟议的两个环境科学与工程 (ESE) 研究项目之一 由北卡罗来纳州立大学 (NC) 领导的“PFAS 环境与健康影响中心” 状态）。拟议中心的主要目标是提供高度相关的数据和信息，以帮助 超级基金研究计划 (SRP) 解决日益严重的全氟烷基和多氟烷基物质问题 （PFAS）污染遍布美国，包括饮用水源的污染。 PFAS 被考虑 PFAS 影响场所的修复是一项重要且及时的公众关注的污染物 健康挑战。颗粒活性炭 (GAC) 吸附是应用最广泛的 PFAS 修复方法 技术。尽管人们对 GAC 对有机污染物的吸附了解很多，但预测 GAC 实验室数据或基本污染物和 GAC 特性的有效性仍然是一个重要因素 挑战。我们的长期目标是开发预测有机微污染物吸附的模型， 包括 GAC 处理系统中的 PFAS。改进现有模型的一个关键障碍是可访问性 GAC 颗粒内部的吸附位点尚不清楚。当前模型的一个重要假设是 污染物在吸附平衡时均匀分布在活性炭颗粒内部。不过，直接 对吸附污染物的观察表明，吸附可能优先发生在外部吸附剂附近 表面。这种区别很重要，因为它可以解释为什么 PFAS 吸附能力随着 减少 GAC 颗粒尺寸以及为什么实验室实验高估了 PFAS 的去除效果 广汽集团。因此，我们的首要假设是，PFAS（以及许多其他有机污染物）的吸附 污染物）优先发生在靠近 GAC 外表面的壳区域。外壳吸附 将通过（目标 1）观察和描述吸附时颗粒内 PFAS 分布来评估假设 平衡和（目标 2）量化和描述 PFAS 吸附/解吸动力学。采用创新的 方法，例如同位素显微镜，我们将开始打开 ​​GAC 仍然代表的“黑匣子”， 直接观察颗粒内PFAS分布。我们将使用来自直接观察的信息 结合吸附平衡和动力学实验的结果来解释我们的壳数据 吸附模型。我们期望模型参数具有物理意义并且可以通过以下方式进行预测 吸附剂和吸附物的基本特性。该项目的结果将支持有效的开发 用于去除 PFAS 的吸附剂、用于 PFAS 修复的（经济）有效的 GAC 处理系统的设计，以及 对已用完的 GAC 的管理选项进行评估。