ERASE-PFAS: Bottom-up synthesis of polymeric membranes for PFAS sequestration

ERASE-PFAS：自下而上合成用于 PFAS 封存的聚合物膜

• 批准号: 2226329
• 负责人: Raul Hernandez Sanchez
• 金额: $ 42万
• 依托单位: University of Pittsburgh
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2022
• 资助国家: 美国
• 起止时间: 2022-09-01 至 2022-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2226329&HistoricalAwards=false
• 关键词: ERASE; PFAS; Bottom; up; synthesis

Anti-corrosion and anti-stain coatings have been increasingly present in our daily lives facilitating the cleaning of objects and/or materials, slowing down material’s deterioration, and protecting them against chemical or thermal stress. Naturally, as these coatings increase in performance, they become more attractive to the public increasing demand, and thus driving forward their manufacture. One large class of molecules forming part of these coatings are the per- and polyfluoroalkyl substances (PFAS). Several thousands of PFAS have been identified, some of which are made in a very large scale. The inherent chemical properties of PFAS makes them essentially unbreakable when they leak into ecosystems. Unfortunately, the presence of PFAS in drinking water across the U.S. is now well-documented and human ingestion of PFAS has been associated with a number of diseases and cancer. The grand challenge ahead of us is to find ways of removing PFAS from the environment, especially when these substances contaminate drinking water sources. The goal of this project is to develop synthetic membranes capable of filtering water to remove the majority of the PFAS to well below the threshold of 70 parts-per-trillion, as established by the U.S. Environmental Protection Agency. Successful completion of the proposed research will develop the chemical pathways and basic understanding to create high-performing membranes to remove PFAS from water, ultimately with the goal of protecting public health. Additional benefits to society will be accomplished through education and training including the mentoring of two graduate students at Rice University.Per- and polyfluoroalkyl substances (PFAS) are molecules generally composed of 1) an anionic head group, carboxylate or sulfonate; and 2) a fluorinated backbone, which are incredibly resistant to environmental degradation. Their chemical and thermal stability made them ideal substances to use to protect materials from degrading or from events such as fires. Enormous quantities of FPAS were produced until health-related effects initiated the ban of certain species around the turn of the century. However, the large quantity that was produced coupled with their environmental persistence has resulted in widespread contamination of the environment, especially drinking water sources. Documented health risks posed by PFAS to humans include severe malformations in pregnant women, cancer in adults, liver malfunction, thyroid disease, decreased fertility, high cholesterol, and obesity. Given that PFAS have weak affinity and binding towards most chemical adsorbents, the challenge ahead is to design membranes capable of removing them from contaminated water. The overarching goal of this project is to design recognition sites for anionic PFAS, which will be later developed and incorporated into membranes used to filter water that would sequester long- and short-chain PFAS. To accomplish this central objective, the project will 1) design recognition sites embedded within supramolecular scaffolds; 2) synthesize, characterize, and determine the anion binding properties of the most promising scaffolds; and 3) polymerize the most promising architectures via olefinic and/or epoxide functional groups incorporated into the supramolecular scaffold, and test their PFAS sequestration properties in aqueous samples. The successful completion of this project will establish the fundamental parameters to enhance PFAS binding within molecular scaffolds to later translate this knowledge into the design of polymeric filtration materials. Education and outreach activities include creating seminars and hands-on workshops for high school and undergraduate students.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.

在我们的日常生活中增加了抗腐蚀和抗染色涂层，支持对物体和/或材料清洁，减慢材料的定义，并保护它们免受化学或热应激。自然，随着这些涂层的性能提高，它们对公众的需求越来越有吸引力，从而推动了他们的制造业。这些涂层的一部分分子是每种和多氟烷基物质（PFA）。已经确定了数千个PFA，其中一些是非常大规模制造的。 PFA的继承化学特性使其在泄漏到生态系统中实质上是牢不可破的。不幸的是，现在美国饮用水中PFA的存在已有据可查，人类对PFA的摄入与多种疾病和癌症有关。我们面临的巨大挑战是找到将PFA从环境中删除的方法，尤其是当这些物质污染饮用水源时。该项目的目的是开发能够过滤水的合成膜，以将大多数PFA拆除到美国环境保护局确定的远低于70分千万亿分的阈值。拟议研究的成功完成将发展化学途径和基本理解，以创建高性能的膜以从水中清除PFA，最终以保护公共卫生的目的。将通过教育和培训来实现社会的额外好处，包括赖斯大学的两名研究生的心理。每种和多氟烷基物质（PFA）是通常由1）组成的分子1）一个阴离子头组，羧酸盐或磺酸盐； 2）氟化主链，越来越对环境降解具有抗性。它们的化学和热稳定性使它们成为保护材料免受降解或火灾等事件的理想物质。生产大量FPA，直到与健康相关的效应在本世纪初期启动某些物种的禁令。但是，产生的大量以及它们的环境持久性导致环境，尤其是饮用水源的宽度污染。 PFA对人类带来的健康风险包括孕妇的严重畸形，成人癌症，肝功能故障，甲状腺疾病，降低生育能力，高胆固醇和肥胖。鉴于PFA对大多数化学吸附剂具有较弱的亲和力，因此面临的挑战是设计能够将其从受污染的水中取出的机制。该项目的总体目标是为阴离子PFA设计识别位点，后来将开发并将其纳入用于过滤水的水的机制中，以隔离长链PFA。为了实现这一中心目标，该项目将1）嵌入超分子支架内的设计识别站点； 2）合成，表征和确定最有希望的支架的阴离子结合特性； 3）通过掺入超分子支架中的烯烃和/或环氧化官能团的聚合将最有前途的体系结构聚合，并测试其在水性样品中的PFAS隔离性能。该项目的成功完成将建立基本参数，以增强分子支架内的PFA结合，然后将这些知识转化为聚合物过滤材料的设计。教育和外展活动包括为高中和本科生创建下水道和动手实践研讨会。该奖项反映了NSF的法定任务，并使用基金会的知识分子优点和更广泛的影响评估标准，被认为是通过评估而被视为珍贵的。