Solar driven degradation of 17 beta-estradiol using composite photocatalytic materials and artificial irradiation source: Influence of process and water matrix parameters

摘要

The study is focused on applicability and effectiveness of solar driven photocatalytic treatment of 17 beta-estradiol (E2), estrogenic hormone recently included in the watch list of priority substances within EU Water Framework Directive. In that purpose, the immobilized TiO2 based composites, made by coupling TiO2 and iron -exchanged zeolite of ZSM5 type (TiO2-FeZ) or another semiconducting material (TiO2-SnS2), were applied as solar active photocatalysts. The applied materials were investigated for their surface, morphology, structure and optical properties using BET method, X-ray diffraction (XRD), scanning electron microscopy / energy -dispersive X-ray spectroscopy (SEM/EDX) and diffuse reflectance spectroscopy (DRS). It was found that TiO2-FeZ has significantly higher specific surface area than TiO2-SnS2, while XRD analyses revealed the presence of crystalline phases of catalyst particles only (TiO2, FeZ and SnS2). SEM/EDX indicated the inhomogeneity of prepared composite films, while DRS showed that composites have lower band gaps comparing to TiO2, which decreased gradually with increasing the wt% of FeZ or SnS2 within composites.