Efficient Degradation of PFOA by Dielectric Barrier Discharge: Interfacial Enrichment, Parameters Optimization, and Synergetic System

Perfluorooctanoic acid (PFOA) is a persistent organic pollutant ubiquitous in aquatic environment, which poses a major threat to ecosystem and human health. In this work, the dielectric barrier discharge (DBD) system degraded PFOA effectively, and the removal rate of PFOA with initial concentration of 10 mg/L and 2 mg/L was 100% within 15 min of discharge. The enhanced degradation effect was observed at higher initial concentration and lower pH value, which was attributed to the enrichment of surfactant-driven PFOA at the gas-liquid interface. Mechanistic investigations based on radical diagnosis and organofluorine intermediate analysis revealed that the degradation proceeds via a synergistic action of electrons and ·OH, with electron-induced defluorination being the dominant pathway. In addition, the degradation efficiency can be further improved by optimizing discharge parameters or adding Fe 2+ , persulfate or choloride. This study supports a micro-reaction mechanism for the degradation of PFOA by DBD plasma, and provides a reference for improving the degradation efficiency of perfluorinated compounds. Graphical The alternative text for this image may have been generated using AI.