Kinetic modeling of photocatalytic degradation of Acid Red 27 in UV/TiO2 process

The photocatalytic degradation of Acid Red 27 (AR27) was investigated using UV radiation in the presence of TiO2-P25 as a function of initial concentration of AR27 ([AR27](0)), oxygen concentration ([O-2]), TiO2-P25 amount, light intensity (I-a), pH and temperature. The activation energy of the photocatalytic degradation of AR27 was 8.24 kJ mol(-1). The photocatalytic degradation rate follows pseudo-first order kinetic with respect to the AR27 concentration. The following rate of decolorization was achieved by kinetic modeling: r(AR27) = 5.294 I-a exp (-8247/RT) (0.79[O-2]/1 + 0.79[O-2]) (4.23[AR27]/1 + 4.23 [AR27](0)) The calculated results obtained from above equation were in good agreement with experimental data. This model predicts the concentration of AR27 during the photodegradation process at different temperatures, light intensities, AR27 and oxygen concentrations. (C) 2004 Elsevier B.V. All rights reserved.