ERASE-PFAS: Tunable Vacuum-Ultraviolet Irradiation Systems with Highly Polarized Redox Environment for Treatment of Per- and Polyfluoroalkyl Substances

ERASE-PFAS：具有高度极化氧化还原环境的可调谐真空紫外线照射系统，用于处理全氟烷基和多氟烷基物质

• 批准号: 2131745
• 负责人: Haizhou Liu
• 金额: $ 40万
• 依托单位: University of California-Riverside
• 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: 2022-01-01 至 2024-12-31
• 项目状态: 已结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2131745&HistoricalAwards=false
• 关键词: ERASE; PFAS; Tunable; Vacuum; Ultraviolet

Per- and polyfluoroalkyl substances (PFASs) are manufactured chemicals that have been used in a variety of industries. PFASs possess exceptional stability, oil- and water-repelling capabilities, and other valuable properties that have resulted in their global distribution in consumer products, electronic manufacturing, and firefighting applications. However, emissions and improper disposal, coupled with environmental persistence, have resulted in widespread PFAS contamination of drinking water sources. Currently, adsorption, ion exchange, and membrane filtration are among the most used technologies for large scale treatment of PFASs in water. However, these treatment approaches do not destroy the PFAS compounds, preventing their more widespread adoption due to the need for frequent regeneration of exhausted media and costly disposal of concentrated waste streams. The goal of this project is to address these limitations through the development of advanced ultraviolet (UV) light-driven reaction processes to effectively degrade PFASs into environmentally benign products. This goal will be achieved through a series of experiments and kinetic modelling of the generation and control of reactive species and their PFAS reaction mechanisms. Successful completion of this project will generate knowledge to develop efficient, cost-effective, and sustainable PFAS treatment technologies for water utilities and industry dischargers to protect public health. Results will be disseminated through scholarly publication to advance knowledge. Additional societal benefits include strengthening and diversifying the Nation’s STEM workforce through outreach, recruitment, and training of underrepresented K-12, undergraduate, and graduate students.The goal of this project is to develop fundamental knowledge of a potentially highly effective but poorly understood vacuum UV light (VUV)-driven photochemical process for the treatment of PFASs. VUV light is a clean and energy-efficient medium that directly photolyzes water to create energetic radicals such as HO·, H· and eaq-. Application of VUV systems for PFAS treatment is currently limited by the low polarized redox environment and low quantum yield of desired radicals. To overcome these deficiencies, research will focus on developing a VUV system with a modulable redox environment to enhance degradation and mineralization of PFASs. Specific research objectives designed to achieve this goal will: i) characterize radical photochemistry under VUV irradiation and examine the reactivity of primary radicals with PFASs; ii) investigate the roles of electron-donating and -accepting solutes on tuning the speciation of transient reactive species and redox polarity of reaction systems for PFAS treatment; and iii) develop a comprehensive kinetic model based on a complete set of elementary reactions and associated rate constants to identify the dominant reactions and predict PFAS degradation under environmentally-relevant conditions. Research will employ advanced state-of-the-science high resolution mass spectrometric analytical tools to assess transformation products of PFASs and infer their reaction pathways during modulated water photolysis. Successful completion of this research will build the science necessary to address the urgent national need for effective, low cost PFAS treatment technologies. Additional societal benefits result from a multi-component educational and outreach effort to: i) engage K-12 students and teachers in environmental chemistry and engineering through seminars, lab visits, and training; ii) involve community college students from underrepresented groups in research; and iii) recruit undergraduate students to participate in a research and mentoring program.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.

人类和多氟烷基物质（PFAS）是在各种行业中使用的制造化学物质。 PFASS潜在的卓越稳定性，石油和依赖水的能力以及其他有价值的特性，这些特性导致了它们在消费产品，电子制造和消防应用方面的全球分布。但是，排放和处置不当，再加上环境持久性，导致了饮用水源的宽度PFA污染。当前，添加吸附，离子交换和膜过滤是水中PFASS大规模处理的最常用技术之一。但是，这些治疗方法不会破坏PFAS化合物，因此由于需要频繁再再生耗尽的媒体和昂贵的浓缩废物流的处置，因此阻止了它们更广泛的采用。该项目的目的是通过开发高级紫外线（UV）轻驱动反应过程来解决这些局限性，以有效地将PFASS降低到环境良性产品中。该目标将通过一系列的实验和动力学建模来实现反应性物种及其PFAS反应机制的生成和控制。该项目的成功完成将产生知识，以开发有效，具有成本效益和可持续的PFAS治疗技术，用于保护公用事业和行业排放以保护公共卫生。结果将通过科学出版物来传播以提高知识。额外的社会益处包括通过外展，招聘和培训代表性不足的K-12，本科和研究生来增强和多样化。 VUV光是一种干净且节能的培养基，可直接光化水以产生能量辐射，例如HO·，H·和Eaq-。目前，VUV系统在PFAS处理中的应用受到所需自由基的低偏振氧化还原环境和低量子收率的限制。为了克服这些缺陷，研究将集中于开发具有模块化氧化还原环境的VUV系统，以增强PFAS的降解和矿化。旨在实现此目标的特定研究目标将：i）在VUV辐照和检查主要自由基与PFAS的反应性下表征自由基光化学； ii）研究了电子散发和 - 接受溶液在调整瞬态反应性物种的规范和反应系统的氧化还原极性中的作用； iii）基于完整的基本反应和相关速率常数建立一个综合动力学模型，以识别主要反应并预测与环境相关的条件下的PFA降解。研究将采用先进的科学高分辨率质谱分析工具来评估PFASS的转化产物，并在调制水光解过程中推断其反应途径。这项研究的成功完成将建立必要的科学，以满足国家对有效，低成本PFAS治疗技术的紧迫需求。额外的社会益处是由多组分的教育和推广工作所带来的：i）通过半人才，实验室访问和培训使K-12学生和教师参与环境化学和工程； ii）涉及来自代表性不足小组的社区大学生研究； iii）招募本科生参加研究和心理计划。该奖项反映了NSF的法定任务，并被认为是值得通过基金会的知识分子优点和更广泛影响的评论标准来评估值得支持的。

项目成果

Hydrogen-polarized vacuum ultraviolet photolysis system for enhanced destruction of perfluoroalkyl substances

• DOI: 10.1016/j.hazl.2022.100072
• 发表时间: 2022-11
• 期刊: Journal of Hazardous Materials Letters
• 作者: Gongde Chen;Sitao Liu;Qingyang Shi;Jay Gan;Bosen Jin;Y. Men;Haizhou Liu