Photocatalytic degradation of reactive red 198 by TiO2-activated carbon nanocomposite

Reactive dyes are used extensively in the textile industry. These dyes are highly water soluble and as a result, their removal from the textile effluent by conventional methods is very difficult. Therefore, many attentions have to be focused on techniques that can lead to the complete destruction of these pollutants. This had led to the study of other methods such as an advanced oxidation process based on photocatalysis. In this research, TiO2–activated carbon nano-composites with different concentrations of the activated carbon (0, 5, 10, 15 weight %) were prepared by a sol–gel method. The structure and morphology of the nanocomposites were evaluated by X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM) techniques. The photocatalytic activity of the nano-composites were evaluated through degradation of reactive red 198 under ultraviolet light irradiations. The results indicated that the TiO2 nano-composite contained only anatase phase and average particle size was 35 nm. The photocatalytic results indicated that the photo-degradation of the reactive red 198 is increased by increasing the activated carbon content to 10 wt% and then decreased. TiO2-5 wt% activated carbon showed the best photocatalytic properties. The photocatalytic results indicated that the reactive red 198 degraded around 42% and 35% during a 210 min irradiation period in the presence of TiO2-5 wt% activated carbon nano-composite and TiO2, respectively.