Visible light active N-doped TiO2 immobilized on polystyrene as efficient system for wastewater treatment

Abstract: The photocatalytic activity of N-doped TiO2 particles supported on polystyrene (PS) surface by using a
solvent-cast method at ambient temperature was evaluated on methylene blue (MB) dye decolourization.
Subsequently, the effect of the new photocatalyst was evaluated in the inactivation of an antibiotic
resistant (AR) Escherichia coli (E. coli) strain selected from the effluent of the biological process of an urban
wastewater treatment plant. N-doped TiO2 particles supported on PS were characterized by UV–vis DRS
reflectance and Laser Raman spectra measurements. The results of photocatalytic tests with MB water
solutions showed that MB can be successfully degraded (83–100%) under visible light after 180 min of
irradiation. The system was also effective in the phenol photocatalytic degradation. Moreover,
photocatalytic process effectively inactivated AR E. coli strain which was reduced by 97% after 30 min
treatment. The developed preparation method could be a promising simple and low cost procedure for
preparing immobilized photocatalysts for large scale commercial applications to wastewater treatment
under direct solar light.