Sol-gel Synthesis of χTiO2/HZSM-5 Composite Photocatalyst on Degradation of Reactive Brilliant Red X3B

Background: Different kinds of materials have been tried to support TiO2. The possible interactions between the supporting materials and the photocatalyst might put effect on photocatalytic activity. Synthesized zeolite with porous structure and large surface area has a long industrial history as adsorbent and catalyst. Photocatalytic degradation of Reactive Brilliant Red-X3B on xTiO(2)/HZSM-5 regarding TiO2 loading percentage and reaction time were investigated. Methods: HZSM-5 supported TiO2 photocatalysts were prepared by a sol-gel method. XRD, SEM, FT-IR, and N-2 adsorption-desorption analyses were measured to the materials. Decoloration of RBR-X3B was conducted to evaluate the activity of the materials. Results: Anatase TiO2 was found in both the XRD patterns of pure TiO2 and xTiO(2)/HZSM-5 samples. The supported xTiO(2)/HZSM-5 has enlarged surface area that is in accordance to the weight percentage of HZSM-5. Photocatalytic activity of TiO2 is enhanced after loading on HZSM-5 with the optimum TiO2 weight percentage of 50%. Total photocatalytic degradation of RBR-X3B dye molecules is achieved after 180 min of irradiation using 50%TiO2/HZSM-5. UV-Vis absorption spectra and FT-IR spectra of RBR-X3B solution during degradation prove the decomposition of RBR-X3B molecules, while the undecomposed triazine is the final residue remaining in the solution. Conclusion: The external surface of HZSM-5 is coated with a layer of TiO2 in different thickness depending on TiO2 loading percentage. Anatase TiO2 forms in both pure TiO2 and the supported xTiO(2)/HZSM-5, while crystallite size of TiO2 shrinks after loading. The distribution of TiO2 on HZSM-5 is beneficial to both adsorption and photocatalytic oxidation of RBR-X3B. RBR-X3B is thoroughly decomposed into small organic substances during photocatalytic process.