Synthesis of Titania Impregnated Kaolinite Nano-photocatalysts for Enhanced Photocatalytic and Recovery Ability in Water Treatment
Semiconductor photocatalysis employing titanium dioxide (TiO2) has been widely reported for its efficacy in removing bio-recalcitrant contaminants in water remediation. However, the low adsorption ability and poor recovery characteristics of the commercial available nano-sized photocatalysts have limit the application of TiO2 for a commercial process. In this work, a modified two steps sol-gel method has been developed to synthesize a titania impregnated kaolinite nano-photocatalysts. The resultant photocatalysts have a constant coating layer of 7 nm while maintaining a relatively shell core with average particle diameter length up to 3.5 microns. The newly synthesized titania/kaolinite nano-photocatalysts was found to not only enhance the adsorption and photo-oxidation ability but provides a photoactive anatase TiO2 for reuse. Results from the photo-degradation trials in a reactor system indicated that the nano-photocatalysts demonstrate a relatively superior photo-activity by completely degrade 40 ppm of aqueous Congo Red in 6 hours. A recycling test for the subsequent photocatalysis application showed that the recovered nano-photocatalysts remain not only a comparable photo-activity, but exhibits an enhance separation ability as compared to the Degussa P-25 TiO2. Current results reveal that the titania/kaolinite nano-photocatalysts have shown promising outcomes of its photocatalytic ability and potential application for an industrial process.