Magnetic graphene TiO2-based photocatalyst for the removal of pollutants of emerging concern in water by simulated sunlight aided photocatalytic ozonation

Abstract

Magnetite and titania have been supported onto graphene for the photocatalytic ozonation of aqueous micropollutants. Titania and magnetite were successfully attached to graphene nanoparticles keeping with a reasonable separation and photocatalytic activity. Although the presence of graphene did not enhance the photoactivity of bare titania, graphene acted as a good support of magnetite nanoparticles and removed the leaching of iron, a problem observed with the graphene free composite. The synthesized photocatalysts were characterized by diverse techniques. The efficiency of the processes involving ozone was assessed by different tools such as HOradical dot exposure vs time, RCT and RHOradical dot,O3 ratios. Photocatalytic ozonation was the most efficient for the removal of the target compound and mineralization. No loss of activity was registered after reusing or appreciable iron leaching. Finally, the catalyst was also tested in a real secondary effluent from a wastewater treatment plant containing ten micropollutants of emerging concern.