The individual and Co-exposure degradation of benzophenone derivatives by UV/H2O2 and UV/PDS in different water matrices

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 center dot) or carbonate radicals (CO3 center dot-) in IN/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 center dot-, 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 center dot, and the co-existence of Br- and Cl- was the sink for SO4 center dot-. 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. (C) 2019 Published by Elsevier Ltd.