Development of Smart Flocculants for the Treatment of PFAS Contaminated Water

开发用于处理 PFAS 污染水的智能絮凝剂

• 批准号: 10081219
• 负责人: Angela Maria Gutierrez
• 金额: $ 16.81万
• 依托单位: BLUEGRASS ADVANCED MATERIALS, LLC
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-10 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10081219
• 关键词: Acrylates; Address; Affinity; Agitation; Alkanesulfonates; American; Attention; Cations; Charge; Country; Development; Dose; Electrostatics; Evaluation; Excision; Exhibits; Family; Flocculation; Food Packaging; Free Radicals; Funding; Hardness; Head; Health; Hour; Human; Hydrogen Bonding; Hydrophobicity; Industrialization; Ionic Strengths; Kinetics; Life Cycle Stages; Liquid substance; Mechanics; Methods; Molecular Weight; N-isopropylacrylamide; Optics; Paint; Performance; Pesticides; Phase; Phase Transition; Poa plant; Polymers; Process; Property; Reaction Time; Recovery; Residual state; Resistance; Salts; Solid; Solubility; Specificity; Sulfonic Acids; System; Techniques; Technology; Temperature; Time; Water; Water Supply; aqueous; base; contaminated water; copolymer; density; dosage; drinking water; hydrophilicity; improved; innovation; monomer; novel; particle; perfluorooctane; perfluorooctanoic acid; polymerization; wasting; water sampling; water solubility

Project Summary Per- and polyfluoroalkyl substances (PFAS) are a family of manmade congeners with dual hydro- and oleo- phobic properties, which is why they have been widely used in firefighting foams, as well as in a multitude of other products such as food packaging, paints, pesticides, and microelectronics. Given their extensive use, high water solubility, and resistance to conventional wastewater treatment methods, PFAS have been detected in public water supplies all over the country causing concern for potential toxic human health effects given their environmental persistence. Flocculation is a widely used separation technique in the removal of suspended solids from water and wastewater. However, traditional flocculants (e.g., inorganic salts and polymeric systems) form aggregate flocs that are usually loosely packed, contain a large amount of water due to their hydrophilicity and as such, require large settling tanks due to the slow process of separation that is required to collect the solids. Furthermore, they have seldom been used to remove dissolved species like PFAS. To address these issues, BAM proposes an innovative “smart” polymeric flocculant that consists of a temperature responsive compound, N-isopropylacrylamide (NIPAAm), modified with a cationic co-monomer dimethylaminoethyl acrylate (DMAEA), and a fluorinated co-monomer short chain trifluoroethyl acrylate (TFEA) and long chain dodecafluoroheptyl acrylate (DDFHA). The combination of these three components results in a polymer which can rapidly capture the dissolved PFAS molecules and form insoluble solid aggregates at temperatures above the lower critical solution temperature (LCST) The core advantages of this system include: (1) slow water retention in the sediment, (2) fast kinetics, and (3) lower energy input by shifting the aggregation temperatures closer to ambient conditions. Specific Aim 1 of the proposed project will involve development and performance evaluation of the cationic and fluorinated modified smart flocculants. More specifically, aim 1 focuses on the material development, where the cationic and fluorinated NIPAAm copolymer with varying composition and molecular weight will be synthesized and characterized. Specific Aim 2 will investigate the flocculation efficiency of the prepared materials in the removal of PFAS, such as perfluorooctanoic acid (PFOS) and perfluorooctane sulfonic acid (PFOA), from contaminated water. To study the PFAS removal efficiency, various environmental conditions (e.g., ionic strength, pH, turbidity) and process variables (e.g., polymer dosage, initial PFAS concentration) will be examined, and the performance will be evaluated through kinetics, sediment compactness, and supernatant composition. Phase I funding of this project will produce a novel smart flocculant system with enhanced solid-liquid separation performance for removing PFAS from contaminated water. When achieved, Phase II of this project will be operated to investigate the efficacy of the prepared copolymer flocculants in drinking water and wastewater.

项目摘要 全氟烷基和多氟烷基物质（PFAS）是一类具有双重氢和油的人造同系物， 憎水特性，这就是为什么它们已被广泛用于消防泡沫，以及在众多的 其他产品，如食品包装，油漆，农药和微电子。鉴于其广泛使用， 水溶性和对常规废水处理方法的抗性，PFAS已在 全国各地的公共供水引起了人们对潜在的有毒人类健康影响的关注， 环境持久性。絮凝是一种广泛应用于去除悬浮物的分离技术 从水和废水中去除固体。然而，传统的絮凝剂（例如，无机盐和聚合物体系） 形成通常松散堆积的聚集絮凝体，由于它们的亲水性而含有大量的水 因此，由于需要缓慢的分离过程来收集 固体此外，它们很少用于去除溶解的物质，如PFAS。解决这些 BAM提出了一种创新的“智能”聚合物絮凝剂， 化合物，N-异丙基丙烯酰胺（NIPAAm），用阳离子共聚单体丙烯酸二甲氨基乙酯改性 氟化共聚单体包括短链丙烯酸三氟乙酯（TFEA）和长链丙烯酸三氟乙酯（DMAEA）。 丙烯酸十二氟庚酯（DDFHA）。这三种组分的组合产生聚合物， 可以快速捕获溶解的PFAS分子，并在高于100 ℃的温度下形成不溶性固体聚集体， 低临界溶解温度（LCST）该体系的核心优点包括：（1）慢水 在沉积物中的保留，（2）快速动力学，和（3）通过改变聚集温度降低能量输入 更接近环境条件。拟议项目的具体目标1将涉及开发和性能 阳离子和氟化改性智能絮凝剂的评价。更具体地说，目标1侧重于 材料开发，其中具有不同组成的阳离子和氟化NIPAAm共聚物和 分子量将被合成和表征。具体目标2将研究絮凝效率 在去除全氟辛烷磺酸（PFOS）和全氟辛烷磺酸（PFOS）等过程中， 磺酸（PFOA），从污染的水。为了研究PFAS的去除效果， 条件（例如，离子强度、pH、浊度）和工艺变量（例如，聚合物剂量，初始PFAS 浓度）进行检查，并通过动力学，沉积物密实度， 和上清液组成。该项目的第一阶段资金将产生一种新型的智能絮凝剂系统， 增强的固液分离性能，用于从污染水中去除PFAS。一旦实现， 该项目的第二阶段将用于研究所制备的共聚物絮凝剂的功效， 饮用水和废水。