| In this study an economical and effective photocatalytic oxidation desulphurization technique isdescribed aimed at the SO2 pollution of our country. The photocatalytic oxidation technique has broughtextensive attention because of its low energy consume,mild reaction condition,simple technique andmanipulation and decreasing secondary pollution.First,two kinds of determination methods of SO2 were compared. The results showed the datawere similar. Since the determination method of SO2 with iodine is more complicate,thedetermination method of SO2 with a set of SO2 analytic apparatus was adopted. Then photocatalyticactivity of outsourcing and iron-doped nanometer TiO2 was compared in the same reaction condition.And the results showed photocatalytic activity of outsourcing TiO2 was better than that of iron-dopedTiO2.The data indicated that photocatalytic oxidation of SO2 over nanometer TiO2 obeyed the rules offirst order reaction kinetics and it can be reduced to a formula: ln Ct/C0=-kat whether TiO2existed or not.The research results showed the reaction rate constant diminished with the increase offrequency of use. In addition,the deactivated photocatalysts can be regenerated to a nearly fulldegree by washing and drying.Effects of reaction elements on photocatalytic oxidation were studied,such as concentration of SO2,reaction temperature and radiation intensity. The research results showed that the efficiency ofphotocatalytic oxidation of SO2 increased with the increase of the initial concentration of SO2 When theinitial concentration of SO2 was below 1200mg/m3,While in the range from 1200mg/m3 to2400mg/m3,the efficiency was not significantly affected by the initial concentration of SO2. In therange from 0℃to 100℃,the efficiency of photocatalytic oxidation of SO2 increased with the increase ofreaction temperature. But in the range from 100℃to 200℃,the efficiency was not significantlyaffected by the reaction temperature,the efficiency of photocatalytic oxidation of SO2 was affected littleby the radiation intensity when the initial concentration of SO2 was low. On the contrary,the efficiencyincreased with the increase of radiation intensity when the initial concentration of SO2 was high.
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