ERI: Underlying Interfacial Phenomena in PFAS- Polymer Sorbent Adsorption

该奖项全部或部分由《2021年美国救援计划法案》（公法117-2）资助。近年来，全氟烷基和多氟烷基物质（PFAS）的家庭和工业市场急剧扩大，尽管这些“永久化学品”在环境中持续存在。全氟磺酸存在于地面、地表水和饮用水中，高浓度的全氟磺酸与严重的健康影响有关，如肝脏和甲状腺疾病以及癌症。因此，必须考虑以减轻有害全氟化砷对环境和健康的影响为重点的水净化工作。目前的PFAS去除技术依赖于吸附剂材料（如活性炭和离子交换树脂），以获得合理的去除率和低成本。然而，这些常见的吸附剂在面对环境相关浓度的PFAS时，存在选择性差、亲和力低、吸附动力学慢的问题，并且吸附剂再生过程是能源密集型的。迫切需要具有选择性和快速去除PFAS的廉价再生的先进吸附材料。本项目研究了在高级吸附剂设计中使用具有可调功能、孔隙率和可控制亲疏水相互作用的氟化大分子。设计方法优先考虑制造的简单性，以消除对昂贵的合成后转换和复杂仪器的需求。研究的重点是了解使用聚合物吸附材料从饮用水中分离PFAS的复杂界面现象。该项目还作为一个教育平台，用于开发研究生水平的课程材料，并吸引本科生和K-12学生参与STEM研究。该项目的目标是开发一种使用新型氟嵌段共聚物的低成本、大规模吸附剂生产策略。候选聚合物利用其在固液界面的自组装来促进消除饮用水中的有毒PFAS。多孔聚合物吸附剂将由廉价的、商业上可用的单体合成，并且不需要合成后转化来实现其所需的功能。吸附剂的设计灵感来自于潜在的界面现象，其中小分子吸附和平衡的疏水/亲水性相互作用可以同时控制。为此，该项目旨在对多孔聚合物吸附剂的工作原理有一个基本的了解。该方法将检查(i)吸附剂功能与短链PFAS和水分子的亲水性相互作用，（ii）在固液界面上平衡疏水碳-氟-氟-碳相互作用，其中聚合物吸附剂是“固体”，而溶解在水中的长链PFAS被认为是“液体”相，以及（iii）调整热力学驱动的自组装现象。消除PFAS的性能将通过从新泽西州不同地区收集的“对照”和饮用水样本进行测试。该项目还将建立一个可持续的方法，以绿色溶剂为基础的回收和再利用废旧的吸收剂。为了将科学发现传达给更广泛的受众，研究者将在蒙特克莱尔州立大学组建一个K-12本科研究小组。该小组将参与(i)实地工作，从附近的工业区收集饮用水样本进行吸附剂测试；（ii）通过在技术知识有限的社区中展示交互式“视觉色码吸附剂演示”进行教育推广。从这项研究中获得的见解也将整合到研究生课程中，以增加学生对聚合物和界面科学与工程领域的兴趣。该奖项反映了美国国家科学基金会的法定使命，并通过使用基金会的知识价值和更广泛的影响审查标准进行评估，被认为值得支持。

This award is funded in whole or in part under the American Rescue Plan Act of 2021 (Public Law 117-2). Household and industrial markets for per- and polyfluoroalkyl substances (PFAS) have dramatically expanded in recent years despite the environmental persistence of these 'forever chemicals'. PFAS are found in ground, surface, and drinking waters and, in high concentrations, have been associated with serious health effects such as liver and thyroid disease and cancer. Thus, water decontamination efforts focused on mitigating the environmental and health impacts of hazardous PFAS must be considered. Current PFAS removal techniques rely on sorbent materials (e.g., activated carbon and ion exchange resins) for their reasonable removal rates and low costs. Yet, these common sorbents suffer from poor selectivity, low affinity, and slow adsorption kinetics when faced with PFAS at environmentally-relevant concentrations, and the sorbent regeneration processes are energy-intensive. Advanced sorbent materials that exhibit selective and rapid removal of PFAS with inexpensive regeneration are urgently needed. This project examines the use of fluorinated macromolecules with tunable functionalities, porosities, and controllable hydrophilic-hydrophobic interactions for advanced sorbent design. The design approach prioritizes manufacturing simplicity to eliminate the need for costly post-synthetic transformations and complex instrumentation. The investigation will focus on understanding the complex interfacial phenomena governing the separation of PFAS from drinking water using the polymer sorbent material. This project also serves as an educational platform for developing graduate-level course materials and engaging undergraduate and K-12 students in STEM research. The goal of this project is to develop a low-cost, mass-scale sorbent production strategy using a novel fluorinated block copolymer. The polymer candidate leverages its self-assembly at solid-liquid interfaces to facilitate the elimination of toxic PFAS from drinking water. The porous polymer sorbent will be synthesized from inexpensive, commercially-available monomers and does not require post-synthetic transformation to achieve its desired functionality. The sorbent design is inspired by the underlying interfacial phenomena, where small-molecule adsorption and balanced hydrophobic/hydrophilic interactions can be controlled concurrently. To that end, the project aims to develop a fundamental understanding of the working principles of the porous polymer sorbent. The approach will examine the interplay of (i) hydrophilic interactions of sorbent functionality to the short-chain PFAS and water molecules, (ii) balanced hydrophobic carbon-fluorine—fluorine-carbon interactions at solid-liquid interfaces, where the polymer sorbent is “solid” and long-chain PFAS dissolved in water is considered a “liquid” phase, and (iii) tuning thermodynamically-driven self-assembly phenomena. PFAS elimination performance will be tested with “control” and drinking water samples collected from various areas of New Jersey. This project will also establish a sustainable approach for green solvent-based recycling and reuse of spent sorbents. To convey the scientific findings to a broader audience, the investigator will form an Undergraduate & K-12 Research Team at Montclair State University. This team will participate in (i) fieldwork to collect drinking water samples from nearby industrial zones for sorbent testing and (ii) educational outreach by presenting an interactive “Visual Color Code Sorbent Demonstration” among communities having limited technical knowledge. Insights gained from this research will also be integrated into a graduate course to increase students' interests in the fields of polymers and interfacial science and engineering.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.