College of Environmental Science and Engineering, Hunan University, Changsha, 410082, PR China; State Key Laboratory of Chemo/Biosensing and Chemometrics, Hunan University, Changsha, 410082, PR China. Electronic address: [Email]
Benzophenone derivatives, including benzophenone-1 (C13H10O3, BP1), benzophenone-3 (C14H12O3, BP3) and benzophenone-8 (C14H12O4, BP8), that used as UV filters are currently viewed as emerging contaminants. Degradation behaviors on co-exposure benzophenone derivatives using UV-driven advanced oxidation processes under different aqueous environments are still unknown. In this study, the degradation behavior of mixed benzophenone derivatives via UV/H2O2 and UV/peroxydisulfate (PDS), in different water matrices (surface water, hydrolyzed urine and seawater) were systematically examined. In surface water, the attack of BP3 by hydroxyl radicals (HO∙) or carbonate radicals (CO3∙-) in UV/H2O2 can generate BP8, which was responsible for the relatively high degradation rate of BP3. Intermediates from BP3 and BP8 in UV/PDS were susceptible to CO3∙-, bringing inhibition of BP1 degradation. In hydrolyzed urine, Cl- was shown the negligible effect for benzophenone derivatives degradation due to low concentration of reactive chlorine species (RCS). Meanwhile, BP3 abatement was excessively inhibited during co-exposure pattern. In seawater, non-first-order kinetic behavior for BP3 and BP8 was found during UV/PDS treatment. Based on modeling, Br- was the sink for HO∙, and the co-existence of Br- and Cl- was the sink for SO4∙-. The cost-effective treatment toward target compounds removal in different water matrices was further evaluated using EE/O. In most cases, UV/H2O2 process is more economically competitive than UV/PDS process.