CAREER: ERASE-PFAS: Mechanistic Investigation of Thermal Decomposition of Poly- and Perfluoroalkyl Substances in the Soil Environment

职业：ERASE-PFAS：土壤环境中多氟烷基和全氟烷基物质热分解的机理研究

• 批准号: 2320966
• 负责人: Feng Xiao
• 金额: $ 50万
• 依托单位: University of Missouri-Columbia
• 依托单位国家: 美国
• 项目类别: Standard Grant
• 财政年份: 2023
• 资助国家: 美国
• 起止时间: 2023-01-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://www.nsf.gov/awardsearch/showAward?AWD_ID=2320966&HistoricalAwards=false
• 关键词: CAREER; ERASE; PFAS; Mechanistic; Investigation; CAREER; ERASE; PFAS; Mechanistic; Investigation

The contamination of soil and water by per- and polyfluoroalkyl substances (PFAS) is a national concern. Certain PFAS chemicals have been detected in the blood of more than 95% of the US population. Soil largely contributes to the quality of groundwater and crops, which are potential human exposure pathways for these chemicals. The challenge of dealing with PFAS contamination results from their chemical structure that leads to strong resistance to biological degradation in the environment. However, thermal processes such as forest fires are known to induce physical and chemical changes of PFAS chemicals in soil. The goal of this CAREER project is to understand the stability and decomposition of PFAS chemicals in soil during thermal treatment. A deeper understanding of these processes is necessary for the development of thermal technologies to clean up soils contaminated by PFAS for the protection of human and ecological health. Successful completion of this research will enable scientists to accurately predict decomposition products of PFAS in various thermal processes. Additional benefits to society result from the training of engineering undergraduates and enhanced learning through participation in hands-on experiments in soil chemistry and physics. Further benefits will accrue from the dissemination of results to the public, remediation professionals, and other stakeholders through outreach, conference presentations, and journal publications. This project is jointly funded by the CBET Environmental Engineering program and the Established Program to Stimulate Competitive Research (EPSCoR).The goal of this CAREER project is to elucidate transformation mechanisms of PFAS in soil during thermal treatment. PFAS reaction pathways at elevated temperatures will be identified through stepwise experiments assessing the thermal treatment of various PFAS classes under different gas phases in various soils and reference soil components. Results will be used to determine the combined effects of soil properties, PFAS molecular structure, and ambient atmosphere on degradation pathways; information critical to assessing thermal treatment as a potential remediation method for PFAS-contaminated soils. A novel aspect of this research arises from the use of an innovative identification approach based on continuously interleaving scans at low and high collision energies of time-of-flight mass spectrometry. Successful completion of this research will yield critical insight into the thermal stability of various classes of PFAS, enhanced understanding of the fate of PFAS in the soil environment during forest fires, and elucidation of mechanisms of thermal decomposition of PFAS. This knowledge is potentially transformative because the high thermal stability of PFAS is an implicit assumption in current environmental fate and transport models. The educational objectives of this project are focused on advancing STEM understanding through the involvement of undergraduate students in well-designed projects. Students will apply knowledge learned in class to address interesting and relevant real-world problems. The diversity of the Nation’s STEM workforce will be broadened through the participation of underrepresented groups in the research. This project is jointly funded by Environmental Engineering program of CBET and the Established Program to Stimulate Competitive Research (EPSCoR).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（PFA）对土壤和水的污染是一个国家的关注点。在超过95％的美国人群的血液中发现了某些PFAS化学物质。土壤在很大程度上有助于地下水和农作物的质量，这是这些化学物质的潜在人类暴露途径。处理PFA污染的挑战是由于其化学结构导致对环境中生物学降解的强烈抗性。然而，已知诸如森林火灾之类的热过程会诱导土壤中PFAS化学物质的物理和化学变化。该职业项目的目的是了解热处理期间PFAS化学物质在土壤中的稳定性和分解。对这些过程的更深入的理解对于开发热技术需要清理由PFA污染的土壤，以保护人类和生态健康。这项研究的成功完成将使科学家能够准确预测PFA在各种热过程中的分解产物。通过参与土壤化学和物理学的动手实验，通过培训工程本科生的培训和增强学习的额外好处。通过外展，会议演讲和期刊出版物，将结果传播给公众，补救专业人员和其他利益相关者将带来更多的好处。该项目由CBET环境工程计划和启发竞争性研究的既定计划（EPSCOR）共同资助。该职业项目的目的是阐明在热处理期间PFA的转化机制。将通过逐步实验评估在各种土壤和参考土壤成分的不同气相下的各种PFAS类的热处理，将在升高温度下的PFA反应途径进行识别。结果将用于确定土壤特性，PFAS分子结构和环境大气对降解途径的综合作用。评估热处理作为一种潜在的补救方法至关重要的信息。这项研究的一个新方面是源于基于在飞行时间质谱法的低碰撞和高碰撞能量下连续交织的创新识别方法。这项研究的成功完成将对各种PFA的热稳定性产生关键的见解，增强对森林火灾期间土壤环境中PFA的命运的了解，并阐明PFA的热分解机制。这种知识具有潜在的变化性，因为PFA的高热稳定性是当前环境命运和运输模型中的隐含假设。该项目的教育目标集中在通过本科生参与精心设计的项目来提高STEM理解。学生将在课堂上运用知识来解决有趣且相关的现实世界问题。通过代表性不足的群体参与研究，该国STEM劳动力的多样性将扩大。该项目由CBET的环境工程计划和启发竞争性研究的既定计划共同资助。该奖项反映了NSF的法定任务，并通过使用基金会的知识分子和更广泛的影响评估标准来评估NSF的法定任务。