Ozonation of Reactive Orange 122 Using La3+-Doped WO3/TiO2/Sep Photocatalyst

Abstract

La3+/WO3/TiO2/sep composites have been prepared by the sol-gel method. The degradation of dye was studied under the influence of various operational parameters such as initial pH, amounts of catalyst, concentrations of the dye, and ozone flow rate. The mineralization of Reactive Orange 122 has been confirmed by chemical oxygen demand measurements. The color removal of dye was found to follow a pseudo-first-order kinetics. Maximum color and chemical oxygen demand removal were 99.9% and 90% respectively, at a dye concentration of 200mg/L, ozone flow rate of 2.0L/min., 0.05g/L weight of catalyst, and pH of 6.9 in 4h. In addition, the catalyst was characterized by X-ray diffraction spectra, Fourier-Transform Infrared Spectroscopy, scanning electron microscopy, and a transmission electron microscope. This work could be a good candidate as a practical application for photocatalytic dye degradation.