Enhanced UV Direct Photolysis And UV/H2O2 For Oxidation of Triclosan And Ibuprofen In Synthetic Effluent: An Experimental Study

Abstract This study aimed to evaluate the implementation of an advanced oxidation system based on UV radiation and UV/H2O2 for degradation of TCS and IBU in synthetic effluent. The assays occurred in a 2L reactor, protected from external light and equipped with a UV lamp (λ = 254nm). The effect of contaminant concentration, fractions of chemical species present, and mineralization were evaluated. In the UV/ H2O2 system, different concentrations of H2O2 were studied for oxidation of the contaminants. The kinetic experiments took place between 75 - 270 min of UV irradiation. The results showed > 99% oxidation of TCS in the direct photolysis system at pH 9.4 after 12 min. The degradation of IBU in the UV/H2O2 system, when 10mg L-1 of H2O2 was used, obtained 97.39% oxidation. We obtained k' values of 0.189 min-1 for TCS when its highest oxidation occurred, and k' values of 0.0219 min-1 for IBU. The system was not able to completely mineralize the contaminants, presenting high values of TOC and COD after treatment, thus suggesting the occurrence of phototransformation.