Photocatalytic and photo-fenton processes by magnetic nanophotocatalysts for efficient dye removal

In this work, a heterogeneous photocatalyst was prepared via sol-gel fabrication of titanium dioxide nanoparticles on the surface of magnetite nanoparticles synthesized by precipitation method. The prepared nanophotocatalysts were characterized by SEM, BET, DRS, VSM, FTIR, and XRD techniques and then used for efficient degradation of Direct Red 80 dye (DR-80) from aqueous solutions using photo-Fenton and heterogeneous photocatalytic processes. Different effective parameters were investigated and the response surface methodology based on Box-Behnken design was used for data analysis. Dye removal with 100% efficiency was obtained for the photo-Fenton process at hydrogen peroxide concentration, initial dye concentration, nanocatalyst dose, and reaction time equal to 14.69 mM, 40 mg/L, 0.15 gr, and 60 min, respectively. Also, dye removal with 100% efficiency was obtained for the photocatalyst process at pH, initial dye concentration, nanocatalyst dose, and reaction time as 5, 50 mg/L, 0.03 gr, and 5 min, respectively. Also, DR-80 dye removal followed first-order kinetic for the photo-Fenton process and second-order kinetic for the photocatalyst process. The synthesized nanocatalyst represented improved properties for high-efficiency dye removal.

Automated summary

In this study, a heterogeneous photocatalyst was prepared using sol-gel method to coat titanium dioxide nanoparticles onto the surface of magnetite nanoparticles, for efficient degradation of DR-80 dye. Experimental results and data analysis showed that the synthesized nanocatalyst exhibited improved properties for high-efficiency dye removal.