Study of norfloxacin degradation by advanced oxidation process using UV/TiO2/H2O2 in an annular reactor

Abstract

Norfloxacin (NFX) residual was frequently found in domestic wastewater, sewage treatment plants, hospital wastewater, and surface water like lakes and rivers. This threatens the ecological balance of the environment. Moreover, normal biological treatment methods (including membrane bioreactor - MBR) are not feasible for the removal
of NFX. In this study, the degradation of NFX through advanced oxidation processes (AOPs) utilising UV/TiO₂ and H₂O₂
as reagents in a laboratory-scale tubular reactor system was conducted. The degradation reactions of NFX could be represented by the LangmuirHinshelwood kinetic model. The influence of factors, including TiO₂ and H₂O₂ concentrations, UV irradiation intensity, and hydrodynamic conditions (specifically, Reynolds number), on the apparent reaction rate constant (k_app) was evaluated. The results demonstrated that the advanced oxidation process employing the combined reagents of UV/TiO₂/H₂O₂ under the following reaction conditions: TiO₂ and H₂O₂ concentrations of 0.2 g/l and 0.0492 mol/l, UV irradiation intensity of 225 W/m², and Reynolds number of 6700, achieved an apparent degradation reaction rate constant for NFX of 0.052 min^-1.