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.

全氟烷基和多氟烷基物质（PFAS）是已用于各种行业的化学品。PFAS具有出色的稳定性、防油和防水能力以及其他有价值的特性，这些特性使其在消费品、电子制造和消防应用中得到全球分销。然而，排放和不适当的处置，加上环境的持久性，导致广泛的PFAS污染的饮用水源。目前，吸附、离子交换和膜过滤是大规模处理水中PFASs最常用的技术。然而，这些处理方法不会破坏PFAS化合物，由于需要频繁再生耗尽的介质和昂贵的浓缩废物流处理，因此阻止了它们的更广泛采用。该项目的目标是通过开发先进的紫外线（UV）光驱动的反应过程来解决这些限制，以有效地将PFASs降解为环境友好的产品。这一目标将通过对反应性物质的产生和控制及其PFAS反应机制进行一系列实验和动力学建模来实现。该项目的成功完成将产生知识，为水务公司和工业排放者开发高效、经济和可持续的PFAS处理技术，以保护公众健康。研究结果将通过学术出版物传播，以增进知识。其他社会效益包括通过推广，招聘和培训代表性不足的K-12，本科生和研究生来加强和多样化国家的STEM劳动力。该项目的目标是开发潜在的高效但知之甚少的真空紫外光（VUV）驱动的光化学过程的基本知识，用于PFAS的治疗。真空紫外光是一种清洁、节能的介质，可直接光解水，产生HO·、H·和eaq-等高能自由基。 目前，用于PFAS处理的VUV系统的应用受到低极化氧化还原环境和所需自由基的低量子产率的限制。为了克服这些缺陷，研究将集中在开发一种具有可调节氧化还原环境的VUV系统，以增强PFAS的降解和矿化。为实现这一目标而设计的具体研究目标包括：i）表征真空紫外辐照下的自由基光化学，并研究初级自由基与PFAS的反应性; ii）研究供电子和受电子溶质对调节瞬时反应物种的形态和PFAS处理反应体系的氧化还原极性的作用;和iii）基于一整套基元反应和相关速率常数开发综合动力学模型，以识别主导反应并预测在环境相关条件下PFAS的降解。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，并推断其在调制水光解过程中的反应途径。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处理技术的迫切需求。额外的社会效益来自多组件的教育和推广工作：i）通过研讨会，实验室访问和培训，让K-12学生和教师参与环境化学和工程; ii）让来自代表性不足的群体的社区大学生参与研究;以及iii）招募本科生参加研究和指导计划。该奖项反映了NSF的法定使命，并被认为是值得的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，

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