Preparation And Photocatalytic Properties Of TiO₂/ZSM-5 Photocatalyst Doped With Samarium And/or Nitrogen

Photocatalytic oxidation technology using TiO2 semiconductor as a photocatalyst has become one of the most promising technology in the wastewater treatment. TiO2 has been used as photocatalyst most commonly and received considerable attention because it is high effective, stable, nontoxic, and cheaper. Since the conventional suspended reaction system has much disadvantage, which mainly lie in the fact that it is difficult to recycle the TiO2 powder after reaction and formation of rapid aggregates in a suspension. Therefore, many researchers have been attempted to support TiO2 on a kind of carrier materials. Among the materials, ZSM-5 zeolite is attractive candidate due to their peculiar properties:with highly ordered porous structure, high adsorption capacity, high thermal stability and so on. Some investigation results indicate that TiO2 supported on ZSM-5 zeolite has showed bright future in degrading organic wastewater. So ZSM-5 zeolite was selected, the TiO2/ZSM-5 photocatalysts were prepared using sol-gel technique in this work.The aim of this paper is to improve the photocatalytic activities of TiO2. This research uses the ion doping to modify TiO2 on base of investigating TiO2 supported on ZSM-5 photocatalyst. Selected rare earth metal Sm and nonmetal N has prepared the adulterating TiO2/ZSM-5 by using the sol-gel method, and characterized by X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR). Through the degeneration methyl orange (MO) solution, the best doping amount of Sm, N doping, influence factors for removal rate of MO were studied. The mechanisms of Sm,N doping to titanium dioxide to influence photocatalytic activity were discussed.On the single doping foundation, Sm, N-co-doped TiO2/ZSM-5 catalyst was prepared and characterized. The effects of catalyst amount, initial MO concentration, initial pH value were investigated. The research indicated that, the removal rate of methyl orange solution over Sm, N co-doped TiO2/ZSM-5 was higher than that of Sm or N single doping.