Iron-doped titania nanoparticles supported on polystyrene for photocatalytic treatment of contaminated water in a continuous system

A visible-light active photocatalyst based on Fe-doped TiO2 and supported by polystyrene pellets (PS) was synthesized for wastewater treatment. “Solid-state” synthesis and doping were carried out and optimized, and the catalyst was characterized by scanning electron microscopy (SEM), Brunauer-Emmett-Teller (BET), UV–Vis-DRS and X-ray diffraction (XRD) analysis. A heat treatment method was developed to support the Fe/TiO2 onto 1 and 3 mm polystyrene pellets without waste production, and photocatalytic activity was investigated on methylene blue and rhodamine B at titania loading up to 50 wt%, both in batch and in a continuous system. Smaller pellets (1 mm) with low titania loading (4 wt%) proved to be the most efficient photocatalyst. Furthermore, the PS-Fe/TiO2 catalyst was easily separated from treated wastewater and reused for up to ten cycles without any loss of catalyst content and activity. The results showed the feasibility of scaling up a laboratory-scale water treatment into a continuous system.