Enhanced UV photoreductive destruction of perfluorooctanoic acid in the presence of alcohols: Synergistic mechanism of hydroxyl radical quenching and solvent effect

Herein, we developed a novel hydrated electron induced approach by simply adding alcohols (0.2 %~0.5 %) as catalysts to enhance the decomposition of perfluorooctanoic acid (PFOA). Different from previous studies, in which high concentration of hydrated electron source materials are generally required, the hydrated electron in this study was generated from UV photolysis of water molecules. Our results clearly demonstrated that the addition of alcohols could not only protect hydrated electron from quenching by hydroxyl radical, but also improve the dispersion of PFOA in solution, thus resulting in higher hydrated electron yield and utilization efficiency. Furthermore, owing to the quenching of proton and oxygen by the generated alcohol radical, the UV/H 2 O/alcohol system exhibited adaptability to different environmental variables, i.e., solution pH and reaction atmosphere. Therefore, the newly developed UV/H 2 O/alcohol system shows promising potential for treatment of PFOA-containing wastewater and investigator derived waste, as alcohol is usually used as the desorption agent. • A UV/alcohol system was developed for PFOA photoreduction degradation. • Alcohol could promote the generation of e aq - by quenching the co-existing •OH. • Alcohol radical could protect e aq - from quenching by oxygen and protons. • Alcohol could enhance the dispersion of PFOA in aqueous solution. • PFOA-containing desorption solution could be directly degraded under UV irradiation.