Advanced oxidation processes in triton x-100 and wash-up liquid removal from wastewater using modified TiO 2/Al 2O 3 photocatalysts

Abstract

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 selfconstructed band reactor during the laboratory studies. The photocatalyst, being typed TiO 2, was supported by porous Al 2O 3 and modified by the addition of Cu, Fe, Zn, Ni, Mo or Co. The photocatalysts were characterised by N2 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 2O 3 photocatalysts modified by the transition metals were efficient only for more complicated compositions of surfactants. The effect of H 2O 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 2O 2 addition. It was also observed that it is not economically justified to conduct such treatment for more than 2 h. © The Author(s) 2012.