Studies Of Photocatalytic Degradation Of Organic Contaminations In Water Over TiO₂ Films

As a new environmental matrial, TiO2 photocatalyst has the attractive applications to waste water treating, air purifying, bactericide,deodorization and surface, self-cleaning. In order to increase the practical application of this waster water treating technology, in this text, we tried to improvement the feasible on economy and technology from preparation of photocatalysists, design of reactor and the influence of different reaction conditions etc.A P25 TiO2 film supported on UV light surface was prepared using sol-gel method at 200℃ calcinations temperature, and the photocatalyst has shown a good stability and performance for the photodegradation of orthocresol solution irradiated with UV light of 254nm, when reaction for 30min, the photodegradation still more then 85%. which not only avoid the filtration and resuspension of the photocatalysts, also has advantage for the design of photocatalytic reactor. the efficiencies of photocatalytic degradation of orthocresol increased than the reactor with glass tube as support.A novel high-efficiencies photocatalytic reactor with the P25 TiO2 film supported on UV light surface was designed. This reactor has shown a good performance with the photodegradation of orthocresol solution. It offered us a method to degradation of aromaticity , this method technics is simple, cost is low and can be avoid the repollution.The novel photocatalytic reactor with the P25 TiO2 filmsupported on UV light surface(UR) have increased the utilance because Light energy transmitted to TiO2 particals without any refraction on the UV light tube. The kinetic study led to one -order reactions,and the efficicency was influenced by prel--iminary concentration, intensity of light and the temperature of reaction as so on. This reactor has shown a good performance with the photodegradation of aether configuration pesticide such as carbofuran and propoxur,the photodegradation rate of 60min achieved 80%.The influence of common cations (Fe2+, Fe3+, Cu2+, Mn2+) and the pH in water was studied. It is shown that add Fe2+ aptly can accelerate the reaction, Fe3+, Cu2+ have little influence to reaction, but Mn2+ can restrain the rate of reaction. The aptitude pH of solution is 5. 5, on the low side or on the high side will restrain the photocatalystic reaction.