Photocatalytic Degradation of Reactive Dyes Using Flyash Supported Ag‐TiO2 Photocatalysts.

In the present study, photocatalytic degradation of five different reactive dyes has been carried out using Ag doped TiO2 supported on coal fly ash (CFA) as a photo catalyst system (Ag‐TiO2/CFA). The photocatalysts were synthesized with varying the percentage of Ag and characterized by XRD, SEM and UV‐visible spectrophotometry. The photocatalytic activity of Ag‐TiO2/CFA photocatalysts was studied for the degradation of reactive dyes in presence of both UV and visible light sources. The degradation was monitored by absorbance measurements. It was found that 3 wt % of Ag doping could bring about maximum degradation (85–95 %) at 3–4 h in presence of visible light. The effect of various parameters such as initial concentration of dye, catalyst amount and pH of solution towards the degradation were studied and it was observed that in acidic conditions the degradation was maximum (pH=3.0) for all the dyes studied. Ability to degrade an industrial waste, use of CFA, a thermal power plant waste as support, small quantities of silver required and degradation under visible light are the environmental as well as economic advantages of this developed catalytic system. [ABSTRACT FROM AUTHOR]