Of Nano Titanium Dioxide Photocatalytic Degradation Of Pollutants

With rapid development of industry, agriculture, pollutants such as industrial wastewater, fertilizers, pesticides, and exhaust gas increase sharply. Water source and air are polluted, which threatens survival of human beings. Therefore, subjects on treatment of the pollutants become important in global range. Nano-TiO2 photocatalytic technology can effectively oxidize and decompose organic pollutants into H2O, CO2, and other inorganic non-toxic small molecules. Research on this topic has become arresting in the field of wastewater treatment, air purification and so on.In the present thesis, we try to degrade methylene blue dye by using nano-TiO2 as photocatalyst. Different UV sources are used to active the reaction. We find that when an 8W linear tube UVB lamp is used, methylene blue can be degraded up to 93.24% with 2g/L nano-TiO2 and 2.5 hours reaction time. With the same nano-TiO2 amount and 5 hours reaction time, a UV LED source radiating 365nm-375nm UV radiation can degrade the methylene blue to 78.38%.TiO2 thin films prepared by using sol-gel method are able to degrade the dye to 74.88% with an 8W linear tube UVB lamp in 5 hours reaction time. Degradation rate is much lower than nano-TiO2 powder.Through the above experiments, I studied nano-TiO2 on the photocatalytic degradation of pollutants, and pointed out future research directions.