Comparison of the life-time of P25 and A11 TiO2 in a labyrinth flow photoreactor

A series of experiments for the comparison of activity and life-time of anatase titanium dioxide, Tytanpol A11 (Chemical Factory "Police", Poland) with Degussa P25 (Germany) was conducted in a labyrinth flow reactor with an immobilized catalyst bed. Phenol, with relatively high concentration up to 100 mg dm(-3), was chosen as a model organic compound. Photocatalytic materials were characterized by determination of: phenol decomposition degree, reaction rate constant, band gap energy, FTIR spectra and phase composition. The pure anatase Tytanpol All shows comparable activity as Degussa P25. However, the life-time of P25 Degussa at high phenol concentration was lower compared to that of anatase All because of the carbon deposit formation on P25 surface. The catalytic activity of rutile phase in. P25 in the reaction of carbon deposits formation is postulated.