WO3–TiO2 based catalysts for the simulated solar radiation assisted photocatalytic ozonation of emerging contaminants in a municipal wastewater treatment plant effluent

Abstract This work is focused on the use of TiO 2 –WO 3 photocatalysts for the removal of a mixture of emerging contaminants through photocatalytic ozonation using simulated solar light as radiation source. Own-made TiO 2 –WO 3 catalysts with WO 3 content around 4 wt% were synthesized using P25 and titanate nanotubes as TiO 2 starting materials. Photocatalysts were thoroughly characterized by means of ICP–OES, N 2 adsorption–desorption isotherms, XRD, TEM, Raman, XPS and DR–UV–Vis spectroscopy. Photocatalytic ozonation using WO 3 based titanate nanotubes composite gave place to complete removal of emerging contaminants (caffeine, metoprolol and ibuprofen in a Municipal Wastewater Treatment Plant effluent aqueous matrix) in less than 40 min with TOC removal up to 64% after 2 h. The highest catalytic activity of this material in the reaction under study compared to bare TiO 2 is due to several effects such as higher activity under visible light radiation joined to an increase in adsorption capacity of organic compounds and catalytic ozonation ability caused by the presence of WO 3 .