Removal of reactive dye using UV/TiO₂ in circular type reactor

Photocatalytic degradation of reactive dye, Red 120, was carried out on TiO₂ particles as photocatalyst under UV irradiation. In this experiment, comparison on the removal of reactive dye by photolysis using UV light alone, photocatalyst adsorption using TiO₂ alone and photocatalysis using UV light with photocatalysts as well as the effect of experimental parameters such as the number of column employed, intensity of the light, pH and TiO₂ dosage affecting the reaction efficiency of photocatalytic degradation of reactive dye in circular type reactor was examined. The results of this indicate that with both UV light illumination and TiO₂ present, reactive dye was more effectively eliminated than with either UV or TiO₂ alone. Photocatalytic degradation of reactive dye increased linearly with increasing UV light intensity. However, over 18 mW cm^-2 of UV light intensity, the efficiency reached a plateau. The photocatalytic degradation rate was greater in acid media than in alkaline media. Photocatalytic removal efficiency of reactive dye increased with increasing TiO₂ dosage. However, over 1.5 g L^-1 of TiO₂ dosage, the efficiency reached a plateau.