Photodegradation of hazardous dye quinoline yellow catalyzed by TiO2

The photocatalytic degradation of hazardous dye quinoline yellow, employing a heterogeneous photocatalytic process using TiO2 photocatalyst irradiated with 6 W UV light source tungsten lamp, has been studied. The effect of various operational parameters, i.e., dye concentration, photocatalyst concentration, pH of the solution, substrate concentration, and electron acceptor such as hydrogen peroxide on the degradation rate of aqueous solutions of quinoline yellow has been examined. The disappearance of the dye follows a pseudo first order kinetics according to the Langmuir Hinshelwood model. Results show that the use of an efficient photocatalyst and the selection of optimal operational parameters may lead to complete decolorization and to sustainable decrease in the chemical oxygen demand (COD) of the dye waste water.

Variation of the rate constant with different concentrations of TiO2.Figure optionsDownload high-quality image (34 K)Download as PowerPoint slideHighlights
► Nonbiodegradable quinoline yellow is removed.
► Process is much faster in basic solutions than neutral or acidic.
► The rate decreases with the increase in dye concentration.
► Complete mineralization of dye can be achieved.