Preparation and Photocatalytic Properties of Nano TiO_2/Nay Composite Photocatalyst

Abstract

The major problems of TiO_2 photocatalyst are easy aggregation and deactivation, and obvious difficulty in separation. In order to overcome some of the drawbacks of TiO_2 photocatalyst in suspension, zeolite(NaY) molecular sieves were used to support TiO_2. The preparation conditions of TiO_2/NaY composite photocatalyst were optimized in this research. Moreover, the effect of NaY on crystal type, phase transition temperature and photocatalytic properties was investigated, and the influence of TiO_2/NaY on the degradation of organic waste water was analyzed. The results indicate that the TiO_2/NaY composite photocatalyst exhibits the optimal photocatalytic activity under the conditions of TiO_2 loading of 35%, sintering temperature of 500 °C, roasting time of 2 h and catalyst dosage of 0.08 g(methylene blue solution of 100 mL). When methylene blue solution of an initial concentration of 20 mg/L was treated for 0.5 h with TiO_2/NaY composite photocatalyst, the photocatalytic degradation rate was 95.42%, 22.3% higher than that of TiO_2. High stability, high ultraviolet light transmission and regular microporous and cage structure of NaY is conducive to not only recycle of TiO_2 but also improvement of photocatalytic activity of TiO_2.

Keywords

• titanium dioxide
• zeolite;molecular sieve
• photocatalysis
• methylene blue