含氟消防泡沫是全球广泛用来扑灭油类、溶剂等引起的B类火灾的利器，同时也被认为是环境中新污染物全氟和多氟烷基物质（PFAS）的主要来源。掌握消防泡沫中的PFAS组分特征是开展风险评估的重要前提，另外，探究PFAS的有效降解手段对于风险防控具有重要意义。本文通过建立能够实现氟平衡的综合性分析方法，全面揭示了典型消防泡沫的PFAS组分特征；阐明了消防泡沫中代表性新型PFAS的高级氧化/还原降解特性和反应机理；探究了PFAS分子结构和泡沫中共存基质对降解效果的影响，并优化处理工艺实现了消防废水的深度脱氟。研究结果为科学评估和管控消防泡沫的PFAS风险提供重要的分析方法、基础数据和解决方案。建立了综合性PFAS分析方法，适用于消防泡沫和受影响水体样品中PFAS的精准定量和快速识别，能够实现样品中的氟平衡。应用该方法首次揭示了我国消防领域代表性样品中的PFAS组分特征，并实现了泡沫浓缩液中的氟平衡（100±20%）。在代表性样品中共识别到71种离子型PFAS和8种中性PFAS。我国替代型产品中PFAS主要分为以下三类：C6调聚型PFAS、C4短链PFAS和具有多种官能团的非直链型PFAS。聚合工艺产品中具有高浓度的氟调聚醇，比调聚小分子产品高1-2个数量级。基于紫外/过硫酸盐（UV/PS）和紫外/亚硫酸盐（UV/SF）体系，结合产物非靶向筛查和量子化学计算，首次揭示消防泡沫中代表性新型PFAS——全氟壬烯氧基苯磺酸钠（OBS）和6:2氟调聚磺酰胺烷基甜菜碱（6:2 FTAB）的高级氧化/还原降解特性与反应机理。UV/SF体系还原脱氟较UV/PS体系氧化脱氟更为彻底。OBS分子中的叔碳原子和醚键为水合电子（eaq?）的优先进攻位点，支链结构会加速脱氟过程。6:2 FTAB在UV/SF体系中的降解机理为eaq?介导的离子端脱烷基反应以及eaq?对氟化端碳碳键的直接进攻。基于消防废水中PFAS可处理性研究，提出了6:2氟调聚磺酸（6:2 FTS）和6:2氟调聚磺酰胺（6:2 FTSAm）的降解速率是C6调聚型消防废水还原处理高效脱氟的关键。采用紫外/真空紫外/亚硫酸盐（UV/VUV/SF）还原氧化复合体系实现了C6调聚型消防废水的深度脱氟，6:2 FTS和6:2 FTSAm可作为处理效果的指示物质。UV/VUV/SF体系较UV/SF体系脱氟率提高了41.9%，矿化率提高24.2%，本文提出了其中的转化路径和反应机理。

Fluorine-containing fire-fighting foam is a widely used tool to extinguish B-class fires caused by oil and solvents, and is also considered a major source of per- and polyfluoroalkyl substances (PFAS) in the environment. Understanding the characteristics of PFAS components in fire-fighting foam is an important prerequisite for conducting risk assessments. In addition, exploring effective degradation methods for PFAS is of great significance for risk prevention and control. In this study, a comprehensive analysis method that can achieve fluorine balance was established to fully reveal the PFAS component characteristics of typical fire-fighting foams. The advanced oxidation/reduction degradation characteristics and reaction mechanisms of representative new PFAS in fire-fighting foams were elucidated. The effects of PFAS molecular structure and coexisting matrices on degradation efficiency were explored, and the treatment process was optimized to achieve deep defluorination of fire-fighting wastewater. The research results provide important analysis methods, basic data, and solutions for scientifically evaluating and controlling PFAS risks in fire-fighting foams.A comprehensive PFAS analysis method was established that is applicable to accurate quantification and rapid identification of PFAS in fire-fighting foam and affected water samples, and can achieve fluorine balance in the samples. The application of this method revealed for the first time the PFAS component characteristics in representative samples in Chinese fire-fighting field, and established the fluorine balance in foam concentrate (100±20%). 71 ionic PFAS and 8 neutral PFAS were identified in the representative samples. PFAS in Chinese substitute products are mainly divided into the following three categories: C6 telomer PFAS, C4 short-chain PFAS, and non-linear PFAS with multiple functional groups. The concentration of fluorinated alcohols in polymerization process products is higher than that in telomer small molecule products by 1-2 orders of magnitude.Based on the UV/persulfate (UV/PS) and UV/sulfite (UV/SF) systems, combined with non-targeted screening of products and quantum chemical calculations, the advanced oxidation/reduction degradation characteristics and reaction mechanisms of representative new PFAS in fire-fighting foams, i.e. sodium p-perfluorous nonenoxybenzene sulfonate (OBS) and 6:2 fluorotelomer sulfonamide alkylbetaine (6:2 FTAB), were revealed for the first time. The reduction defluorination of UV/SF system was more thorough than the oxidation defluorination of UV/PS system. The tertiary carbon atom and ether bond in OBS molecule are the preferred attack sites for hydrated electrons (eaq?), and the branched structure accelerates the defluorination process. The degradation mechanism of 6:2 FTAB in UV/SF system involves eaq?-mediated terminal dealkylation reaction and direct attack of eaq? on fluorinated end carbon-carbon bond.Based on the study of the treatability of PFAS in fire-fighting wastewater, it was proposed that the degradation rates of 6:2 fluorotelomer sulfonate (6:2 FTS) and 6:2 fluorotelomer sulfonamide (6:2 FTSAm) are key to the efficient defluorination of C6 telomer-type fire-fighting wastewater. The deep defluorination of C6 telomer-type fire-fighting wastewater was achieved by UV/vacuum UV/sulfite (UV/VUV/SF) composite system, and 6:2 FTS and 6:2 FTSAm can be used as indicator substances for treatment effectiveness. The defluorination rate of the UV/VUV/SF system was increased by 41.9% compared to that of the UV/SF system, and the mineralization rate was increased by 24.2%. The transformation pathway and reaction mechanism are proposed in this paper.