Photocatalytic discolorization of methyl orange solution by Pt modified TiO2 loaded on natural zeolite

Pt modified TiO2 loaded on natural zeolites (Pt-TiO2/zeolites) was prepared by sol-gel technique and photoreductive deposition method. The photocatalysts were characterized by UV-vis absorption spectrum, FTIR spectrum, BET and X-ray diffraction. Their photocatalytic activities were examined by the photocatalytic decolorization of methyl orange solution under UV light irradiation. The results show that Pt doping induced the enhancement of photocatalytic decolorization and optimal Pt doping is about 1.5 wt.% with 86.2% of decolorization rate under 30 min irradiation time. The effects of calcinated temperature, catalyst concentration, oxidant H2O2, and pH on the photocatalytic activities were studied. The repeatability of photocatalytic activity was also tested and the decolorization rate was 81.9% of initial decolorization rate after five cycles. (c) 2007 Elsevier Ltd. All rights reserved.