Photocatalytic Degradation of the Textile Dye Reactive Orange 16 in the Presence of TiO2 Suspensions

Abstract

The photocatalytic degradation of Reactive Orange 16, a textile azo dye, has been investigated in aqueous heterogeneous solutions containing titanium dioxide TiO₂ as photocatalyst. The disappearance of the organic molecule follows approximately a pseudo-first kinetic order according to the Langmuir-Hinshelwood model. CO₂, NO₃ ⁻, NH₄ ⁺ and SO₄ ²⁻ ions have been identified as mineralization products. Various commercial photocatalysts were compared with respect to their decolorization efficiency, as well as the production of CO₂. The effect of pH and H₂O₂ on the reaction rate was ascertained.