Degradation of Aqueous Quinoline Using Persulfate Activated by γ-Fe2O3@Carbon Composites and Enhanced by UV Irradiation

摘要

In this study, the ultraviolet(UV)enhanced γ-Fe2O3@Carbon composite(γ-Fe2O3@C)persulfate(PS)activation system was successfully constructed for quinoline degradation. Quinoline can be effectively degraded with the removal efficiency of 99% and TOC removal efficiency of 86% in 60 min at pH 7.5 due to the increased contribution of SO4~(*·)and *OH caused by the assistance of UV irradiation in the γ-Fe2O3@C/PS system. Control experiments showed that the quinoline removal efficiency might be primarily restricted by the limited PS dosage and the system had a wide pH application range of 3~ 11, good tolerance and strong anti-interference ability. In the presence of the reactive oxygen species(SO4~(*·), ~·OH and ~1O_2),quinoline was first decomposed into formic acid, aniline, ethylbenzene and other intermediate products through hydroxylation, oxidative dehydrogenation and ring-opening reactions and then most of them were mineralized into carbon dioxide and water eventually.