Removal of Perfluorooctanoic Acid (PFOA) in Water Using a Multi-Pin Over Liquid Dielectric Barrier Discharge Reactor

Abstract

This study investigates the degradation of perfluorooctanoic acid (PFOA) in aqueous solution using an air-operated multi-pin over liquid dielectric barrier discharge reactor (DBD). PFOA concentration decreased during the initial treatment stage but reached a plateau after approximately 30 min (25 kWh m−3), indicating limited further conversion. Total organic carbon (TOC) declined slowly, suggesting progressive oxidation of transformation products rather than continued PFOA degradation. Fluoride release of less than 1% indicated limited mineralization. Energy yield decreased with time, indicating kinetic saturation. A broader distribution of transformation products was revealed in coupling tests with activated carbon, indicating an influence on plasma-induced transformation pathways. Nevertheless, these findings show that air-fed DBD plasma exhibits inherent limitations for PFAS oxidation under the experimental conditions investigated.