| This paper has fully studied and analyzed the present status and development trend of the photocatalytic oxidation technique in the world. On this basic, TiO2 film is successfully prepared on theγ-Al2O3 granular by sol-gel process. The catalysts showed long lifetime, being readily available, and easy to be prepared and handled, which have good application potential in water treatment process.We selected phenol as model reactive organic compounds towards molecular ozone and catalytic ozonation. Among of the parameters, some ones which changed the mass transfer of ozone had more effective behavior than others which accelerate the reaction rate. The results showed-that under certain conditions phenol removal efficiency was continuously enhanced with the increase of the ozone flow rate and the decrease of temperature. Meanwhile, the initial pH value has an important effect on the phenol removal and it will be the greatest when the pH value is in the range of 8 to 10. While oxalic acid as model poorly reactive organic compounds towards molecular ozone, then selected TiO2/γ-Al2O3-catalyzed degradation oxalic acid with UV by the mean time. This study includes two parts: O3, O3/UV, O3/TiO2/γ-Al2O3 and O3/TiO2/γ-Al2O3/UV degradation of phenol solution, and catalytic ozonation of oxalic acid.O3/TiO2/γ-Al2O3/UV degradation of oxalic acid solution was better than ozonation or photocatalysis. Oxalic acid was oxidized through hydroxyl radical mechanism, different from degradation of phenol, the chemical reaction was the bottle-neck step of the whole process. Some experimental parameters, especially such as pH value, concentration of metal ions and temperature effect strongly the reaction. PH value was the key factor which determined the oxidation reaction take place or not, the best efficiency of catalysis is gained at moderate concentration of catalyst, 150g in this experiment, and the reaction rate accelerate when temperature rising.
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