Advanced Oxidation Processes in Triton X-100 and Wash-up Liquid Removal from Wastewater Using Modified TiO(2)/Al(2)O(3) Photocatalysts

Photocatalytic methods were applied to remove the recalcitrant or toxic pollutants from the water. The two models of wastewater containing either non-ionic surfactant Triton X-100 or commercially available wash-up liquid were tested in a self-constructed band reactor during the laboratory studies. The photocatalyst, being typed TiO(2), was supported by porous Al(2)O(3) and modified by the addition of Cu, Fe, Zn, Ni, Mo or Co. The photocatalysts were characterised by N(2) adsorption–desorption, XRF, XRD, SEM-EDX, Raman and UV–Vis spectroscopy. All catalysts were efficient in the photocatalytic oxidation of surfactants, and they enabled at least 85 % COD reduction. TiO(2)/Al(2)O(3) photocatalysts modified by the transition metals were efficient only for more complicated compositions of surfactants. The effect of H(2)O(2) (0.01 vol.%) addition was also examined and compared with a type of compound and catalyst used—in this case a positive effect for Triton X-100 was only observed over the photocatalyst modified by Ni. When it comes to the wash-up liquid photoremoval, all studied photocatalysts seem to be slightly influenced by H(2)O(2) addition. It was also observed that it is not economically justified to conduct such treatment for more than 2 h.