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.