Kinetic Study of the Metal Ions Doped TiO2 Samples for the Photocatalytic Degradation of E 131 VF

The present work is focused on the influence of the metal salts on the photocatalytic efficiency of TiO2 for the elimination of E 131 VF food colorant. Two series of TiO2 photocatalysts loaded with Fe(II) and Cu(II) were p repared by using the wet impregnation method. The samples were characterized by XRD, IR, Raman and scanning electron microscopy. The degradation of th e food colorant was followed by the measurement of the absorbance. The kinetics of degradation fitted well to the zero pseudo order with Cu-TiO 2, but it followed the 1 order with Fe-TiO2. In general, the photoactivity of TiO2 was reduced by the presence of the transition metal ions, even at low molar ratio %. The recalcination of the doped s amples at higher temperatures reduced more the degradation activity. Several rea sons were suggested to explain the dramatic decrease in the activity of the prepared s amples.