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With China's economic development and social progress, water pollution problems have become increasingly prominent, has become an important environmental issues of social concern. Nano-TiO2 photocatalytic technology with its advantages of low cost, mild reaction conditions, the degradation effect become effective potential pollution control methods. At home and abroad in more the pure TiO2 the catalyst degradation sewage undertaken research. Aniline wastewater as model pollutant effects of the metal and nonmetal ion codoped rare earth doped heteropoly acid by TiO2 photocatalysis treating wastewater. Pure TiO2 were prepared by the sol - gel method and doped Fe3 the Fe3 / F? To Nb5 / F? TiO2 powder photocatalyst by infrared spectroscopy (FT-IR), X-ray diffraction (XRD), spectrophotometer means of electron spectroscopy (EDS) to characterize the catalyst, and the main factors investigated Photocatalytic Degradation of aniline wastewater. IR spectra analysis, when the doping amount of Fe is 0.05%, the characteristic peak of TiO2 2 366.66 cm? 1 and 472.56 cm? 1 there are in the vicinity of similar characteristic peaks, but the strength is somewhat increased, while 472.56 cm? At the peak moves to the right, which is together and doping the Hou Nami powder particle diameter of the Fe-O bond with the Ti-O stretching vibration becomes large caused. IR spectra can be seen to the Fe3 ion TiO2 polymorphs play a role with TiO2 composite together. XRD analysis showed that - TiO2 catalyst, the average particle diameter of about 12.57 nm, and Fe3 / F,? Doping after the particle size increases, the average particle diameter of 13.16 nm, the structure of the catalyst remains anatase, but to improve the photocatalytic activity . Three different doped TiO2 catalysts doping amount were 0.05%, 0.05% / 2%, 0.1% / 1% after 2 h UV irradiation reaction, aniline wastewater degradation rate were 97.64%, 98.20%, 98.32%. Preparation of rare earth ions (Ce3, Nd3, Pr3) doped TiO2 nanocrystals. FT-IR, the catalysts were characterized by XRD techniques. The results show that: the rare earth ion doping can significantly improve the photocatalytic activity of TiO2, the concentration of different types of doped rare earth ions, improve the effect of TiO2 photocatalytic activity is also different. Neodymium optimum doping concentration of 0.1%, the degradation rate can be the optimum doping concentration of cerium in a degradation rate of 0.5% can be achieved 99.20%, 98.47%; In addition, rare earth elements, and non-metallic elements codoped also improve the photocatalytic activity of titanium dioxide in a certain extent. Neodymium 0.05% fluoride 2% codoped better than pure titanium dioxide increased the degradation rate of up to 99.08%; 2% cerium 1% with fluorine doped degradation rate of 96.14%. Titanium dioxide as the carrier prepared by impregnation immobilized polyoxometalate photocatalyst. The immersion time, sintering temperature, the carrier used in an amount, and impregnating the impact of concentration on the catalytic activity of titania as a carrier of solid light-carrying, and the prepared solid photocatalyst characterized by infrared spectroscopy. Phosphotungstic acid aqueous solution impregnated TiO2 powder, dipping time of 28 h, impregnation concentration of 0.04 mol / L, the drying temperature of 85 ° C, the muffle furnace sintering temperature of 400 ° C, sintering time of 2 h, titanium dioxide solid load 0.5 g, the catalyst prepared photodegradation highest activity. Compared with pure TiO2 photocatalyst, photocatalyst phosphotungstic acid / TiO2 Immobilized catalytic activity has been greatly improved, visible light, the degradation rate of aniline increased to 60.3% from 34.2%. TiO2 powder is impregnated with an aqueous solution of phosphomolybdic acid, dipping time of 26 h, impregnating solution concentration of 0.04 mol / L, the drying temperature of 85 ° C, the muffle furnace sintering temperature of 450 ° C, sintering time of 2 h, titanium dioxide solid load 0.6 g, the catalyst prepared photodegradation highest activity. Compared with pure TiO2 photocatalyst, photocatalyst phosphomolybdic acid / TiO2 Immobilized catalytic activity has been greatly improved, visible light, the degradation rate of aniline increased to 74.5% from 34.2%. The results show that, phosphotungstic acid and phosphorus molybdate solid contained on the surface of titanium dioxide, has been catalytic activity than pure titania stronger composite light catalyst, its for aniline degradation rate than pure titanium dioxide, respectively, to improve the 26.1% and 40.3%.
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