Composite template-free TiO2 photocatalyst: Synthesis, characteristics and photocatalytic activity
Novel template-free millimetre-size TiO2 photocatalyst spheres with a considerable degree of consistency in their shape and size were developed using sol–gel route. The photocatalyst was prepared by developing a bond between the pre-calcined TiO2 particles in suspension of TiO2 nanoparticles (composite sol–gel) formed by the assistance of a polymeric compound structure. Synthesis variables such as reactant concentrations, pH, drying process and calcination temperature were studied in order to improve the attrition resistance, while maintaining the photoefficiency of the catalyst. X-ray diffraction (XRD), scanning electron microscope (SEM), BET specific surface area and thermo gravimetric analyses (TGA) were used to characterize the photocatalyst. The photocatalytic activities of this mechanically robust photocatalyst was assessed in a laboratory scale fluidized bed photocatalytic reactor using UV irradiation at 254 nm and formic acid (FA) as a model organic compound.
Graphical abstractFigure optionsDownload full-size imageDownload as PowerPoint slideResearch highlights► Novel approach to the synthesis of mechanically stable composite TiO2 photocatalyst spheres with very low attrition during fluidization. ► Examines thoroughly the effect of various parameters influencing the attrition resistance of the photocatalyst. ► Evaluates and presents the efficacy of the composite photocatalyst spheres through well controlled experiments and through comparison with the standard P-25 titania photocatalyst.
Journal: Applied Catalysis B: Environmental - Volume 104, Issues 1–2, 27 April 2011, Pages 127–135