Preparation and characterization of TiO2 nanofibers by hydrothermal method for removal of Benzodiazepines (Diazepam) from liquids as catalytic ozonation and adsorption processes

TiO2 nanofibers were synthesized by hydrothermal method and characterized by X-ray diffraction (XRD), field emission scanning electron microscopy (FE-SEM), transmission electron microscopy (TEM). The specific surface area of the nanofibers was determined using the Brunauer-Emmett-Teller (BET) method. The value of specific surface area was 67.89 m(2) g(-1) for TiO2 nanofibers. The aim of this study was to evaluate the effectiveness of TiO2 nanofibers in removal of Diazepam from water solutions. The maximum adsorption capacity occurred in Diazepam concentration of 20 mg/l, contact times of 60 min, pH = 6 and adsorbent mass of 0.09 mg/L The result of the Langmuir and Freundlich isotherm study show that of TiO2 nanofibers behave more similar to Langmuir isotherm model. The adsorption process was exothermic and TiO2 nanofibers follow the pseudo second order kinetic model and the other adsorbent follows the pseudo first order kinetic model. Since TiO2 nanofibers are available and affordable and according to this study have high capacity for removal of Diazepam. Finally, the catalytic ability of TiO2 nanofibers was investigated for catalytic ozonation of Diazepam. Results showed that TiO2 nanofibers have high efficiency in catalytic ozonation of Diazepam. (C) 2017 Elsevier B.V. All rights reserved.