| As the new century, our country enjoy rapid economic growth, is also facing serious energy shortages and environmental pollution problems. This is the current and future generations of people living and health is very unfavorable view of sustainable development thus emerged, from this perspective we should understand the importance of various material of construction must also be accompanied by a high degree of emphasis on waste, emissions processing and recycling. But you want to do is not easy. Until the emergence of photocatalytic technology provides us with an ideal way.This technology can be used as an inexhaustible solar processing hazardous substances, improve the environment, and will not cause secondary pollution, ecological use of resources to achieve the purpose of great attention by scientists at home and abroad. In recent years, many scholars at home and abroad have carried out extensive research and has made great achievements, of which, represented by TiO2 photocatalytic technology has become a hot research. Nanometer TiO2 photo-catalyst has been proved to have outstanding performance under UV-light,, so TiO2 due to its highly chemical stability, highly photo-catalytic efficiency and no pollution to the environment is widely used in many fields including self-cleaning, removing bacterium and breaking down organic pollutants, especially in destroy the industrial waste water. However, due to wide band gap, TiO2 has no performance under the visible light irradiation.So, how to improve its photo-catalytic efficiency under has become the focus of the direction of laboratory research.In this dissertation, the Ag/Mo6+/TiO2 photo-catalyst was prepared by a simple method and acid scarlet 3R wastewater as the study object was leading research direction. The results showed that this new type of catalyst was highly responsive to visible light. The main contents were presented as follows:1. The pure TiO2, Mo6+doped on TiO2, Ag loaded on TiO2, Mo6+ doped and Ag loaded on TiO2 were prepared by sol-gel method and Photo-catalytic reduction method, the structure and shape were characterized by XRD and SEM. The results show that whether Mo6+-doped, Ag-attached or Mo6+-doped and Ag-attached TiO2 powders grain size of them compared with the pure TiO2 are smaller, in which Ag/Mo6+/TiO2 powder is the smallest. The diameter is about 19.6nm.Mo6+-doping and Ag-attached inhibited transformation the anatase to rutile.2. According to the analysis of XPS spectrum and UV spectrum, Mo is+6 valence state into the TiO2 lattice and replace a portion of Ti4+, and Ag is 0 valence attached to the surface of TiO2; TiO2by Mo6+-doping and Ag-loading occurred with the red-shifted and extension of the spectral response range to the visible light.3. We studied the optimal amount of doped Mo6+and loaded Ag and calcination temperature,and discussed under visible-ligh catalytic activity of the Ag/Mo6+/TiO2 compared with that of the Mo6+/TiO2,the Ag/TiO2 and pure TiO2 photo-catalysts by using them to decompose the Acid scarlet 3R wastewater as photo-catalytic reaction of model compounds. The results show that the optimal amount of doped Mo6+ and loaded Ag was 4.5% and 2% (mass fraction), and the optimal calcination temperature was 500℃and the degradation effect of the Ag/Mo6+/TiO2 photo-catalyst was significantly higher than that of the other samples. Decomposed under visible light the degradation rate of acid scarlet 3R wastewater achieves 87.6% after 7 hours.4. We studied the kinetics for the Ag/Mo6+/TiO2 photo-catalysts to decompose the Acid scarlet 3R wastewater and the effects of initial acid scarlet 3R concentration,quantity of catalyst and pH.The global kinetics was described by an exponential equation derived as k=0.5183C0-0.4866Q0.2378R0.1708.The deviation between calculated and experimental results was approximately within 5%. |
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