| In 1972, Fujishima and his colleagues found that mono-crystalline semiconductor could catalyze the decomposition of H2O. Since then, through studious research and study, semiconductor photo catalysts have been widely used in air purification, drinking water dis-infection and industrial waste disposal. As one kind of semiconductor photo catalyst, TiO2 is one of the hotpoint because it is innoxious and it has high catalytic power and stability. But powdered TiO2 has many shortages such as low catalytic activity, difficulty in separation and recovery. Key problem in this research is modification of TiO2 and immobilization technology. Because the price of standard glass is low and it has a lot of usages, it can be fabricated into self-cleaning materials by spread TiO2 member in its surface, which has extensive utilities.On the basis of reading a lot of literatures, SG-2 self cleaning glass, which is based in the raw material of TNB, has been produced by sol-gel process and dip-coating method. In this thesis, several factors have been probed intensively, namely: dosage of Fe3+, dosage of PEG, number of the layers and so on. Mechanism has been discussed. Photocatalytic effect of this product in the degradation of simulated pollutants and real pollutants.Through experiments, it shows that when the ratio ofTNB,ethanol,triethanolamine,H2O is 1:34:1.25:1.5(in mol), the concentration of PEG is 0.13wt%, the concentration of Fe3+ is 0.12wt% and the number of the layers is 2, SG-2 has its optimum characteristics. Main parameters of this product is: average transmittance rate of visible light is 68.4%, average transmittance rate of ultra-violet light is 49.1%, degradation of Acridine orange simulated wastewater is 62.5%. In natural environment, woolen washing wastewater can be degraded by 62.5% in 90min by this product and most of the oil film in the surface can be degraded in 60min. After being kept indoor and outdoor for 2 weeks, transmittance of SG-2 can be kept as 35.2% and 48.5% respectively, which is better than normal glass. After cleaning, transmittance of this product can be raised to 61.2% and 68.6%, which is better than normal glass too. SG-2 has superhydrophilic property with 60min soakage time and 1.5h retaining. Based on the latest literatures and related experiment results, it is concluded that microemulsion process based inorganogels method has better effect on the controlling of nano-TiO2 dimension and product made by this method has better photocatalytic activity. In sequence, on conditions of optimum raw materials ratio from sol-gel, formulating of recipe of precursor has been achieved. When the ratio of TNB,ethanol,triethanolmine,H2O,TX-100,n-hxyl alcohol,cyclohexane is 1:34:1.25:1.5:6.5:2.5:19, the concentration of PEG is 0.74g/L, the concentration of Fe3+ is 0.69g/L and the number of the layers is 2, ME-S2 can be produced, whose characteristics are: average transmittance of visible light is 70.6%, average transmittance of ultra-violet light is 48.1% and the degradation of acridine orange simulated wastewater is 88.7%. The results of experiments in natural environment show that: degradation of woolen washing wastewater can be 72.3% in 90min by ME-S2, which is better than the effect of SG-2. Oil film in the surface can be degraded completely in 60min. After being kept indoor and outdoor for 2 weeks, transmittance of ME-S2 can be kept as 40.8% and 52.4% respectively. After cleaning, transmittance of this product can be raised to 73.2% and 71.1%, which is better than normal glass and SG-2. ME-S2 has the same superhydrophilic property as SG-2, but soakage time of this product is shorter.ME-S2 and SG-2 have their potential application values, within which, ME-S2 has the better qualities but its cost is higher.
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