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.

摘要 （环境科学与工程）研究项目4 项目4是两个环境科学与工程（ESE）研究项目之一， 由北卡罗来纳州州立大学（NC）领导的“PFAS环境和健康影响中心 州）。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）解决全氟烷基和多氟烷基物质日益严重的问题 （PFAS）污染，包括饮用水源的污染。PFAS被认为 污染物的新出现的关注，并修复PFAS影响的网站是一个关键和及时的公众 健康挑战。颗粒活性炭（GAC）吸附是目前应用最广泛的PFAS修复方法 技术.尽管对GAC吸附有机污染物的研究已经有了很多了解， 从实验室数据或从基本污染物和GAC属性的有效性仍然是一个显着的 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PFAS，在GAC处理系统中。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是未知的。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GAC颗粒内部。然而，直接 对吸附污染物的观察表明，吸附可以优先发生在外部吸附剂附近 面这种区别是重要的，因为它可以解释为什么PFAS吸附能力随着时间的推移而增加。 降低GAC颗粒尺寸以及为什么实验室实验高估了PFAS的去除效果 GAC。因此，我们的总体假设是，PFAS（以及许多其他有机物）的吸附 污染物）优先发生在靠近GAC外表面的壳区域中。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（目的2）定量和描述PFAS吸附/解吸动力学。使用创新 方法，如同位素显微镜，我们将开始打开“黑匣子”，GAC仍然代表， 直接观察颗粒内PFAS分布。我们将使用直接观察的信息， 结合吸附平衡和动力学实验的结果来解释我们的数据与壳 吸附模型我们期望模型参数将是物理上有意义的，并且可以从 基本的吸附剂和吸附物性质。该项目的成果将支持制定有效的 用于PFAS去除的吸附剂，用于PFAS修复的（成本）有效的GAC处理系统的设计，以及 对用过的活性炭的管理方案进行评估。