Effect of process parameters and identification of reaction products during advanced oxidation of benzophenone-3 in water

Current wastewater treatment techniques are not completely effective in removing UV filters (UV F) (Li et al., 2007), and the compound benzophenone-3 (BP3, oxybenzone) was measured at relatively high values in raw wastewater and primary effluent. Advanced oxidation processes, which generate hydroxyl radicals, are a promising tool for the removal of persistent organic pollutants.Given the lack of data and knowledge on AOP removal of UV F compounds, the aim of this study was to systematically investigate the removal of BP3 in water when treated with ozone and/or hydrogen peroxide. On the one hand, the focus is put on the effect of operational variables on BP3 removal and ozone consumption. The effects of ozone inlet concentration, temperature, pH, hydrogen peroxide and the addition of the hydroxyl radical scavenger t-butanol were evaluated. Besides that, BP3 main ozonation and peroxone byproducts have been identified and structurally characterized by the use of high performance liquid chromatography coupled to quadrupole-time-of-flight-tandem mass spectrometry (HPLC-QqTOF-MS/MS) in order to gain insight in the advanced oxidation pathway of BP3 in water.