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The reaction mechanism of O3 with bromide ion in aqueous solution was studied by ion chromatography and UV-Vis spectrometry instruments. Ion chromatography analysis showed that only 10% of Br- which was oxidized by ozone was formed into bromate ion. The results demonstrated that the final products of the oxidation reaction were identified as Br2 and Br3- except for BrO3-. The formation of Br3- which was yielded from the reaction of Br2 with Br- was the major process in the reaction of Br attacked by O3. The characteristic absorption spectrum of Br3- with an absorption peak at 260 nm was also investigated. The results may provide helpful information about the mechanism of the oxidation reaction of Br- with O3 and fate of Br- or its derivatives in the environment by the oxidation processes.

The photolysis of simulating carbon disulfide malodorous gas was studied under UV irradiation emitted by microwave electrodeless lamps. Experiments results show that the photolysis of carbon disulfide is determined by the initial concentration, residence time and gas humidity. When air velocity is 0.2 m/s, initial concentration is about 100 mg/m3, and gas humidity is about 40%, the conversion ratio of carbon disulfide can reach to 75% with microwave electrodeless mercury lamp and 50% with microwave electrodeless iodine lamp. The mechanism of carbon disulfide photolysis was further studied. It is concluded that the photolysis of carbon disulfide is probably a collective action of direct photolysis and *OH radical oxidation.

We verified that C6F6, a typical perfluorine compound, could be photocatalytic degraded by H3PW12O40. The defluorination of C6F6 was determined as a function of irradiation time, pH, initial concentration of H3PW12O40, and additives as well. The defluorination of C6F6 increased with the irradiation time. Acid condition, especially pH = 1.0 is preferred. 3 mL solution of 2.0 x 10(-4) mol/L C6F6 and 5.0 x 10(-6) mol/L H3PW12O40 was irradiated for 20 min and the defluorination of C6F6 was equal to 208.1%. O2, KMnO4 and K2S2O8 added in the solution were able to increase the defluorination of C6F6 via oxidating [PW12O40](4-). The defluorination of C6F6 would decline in the presence of alcohol and aromatic compounds.

SF5CF3 was identified recently as a potent greenhouse gas with strong radiative force and long atmosphere residential life. Spark discharge method was used to take simulative investigation on the elimination of SF5CF3 from atmosphere under discharge here. The results show that SF5CF3 was dissociated under discharge and formed some compounds containing S, F, O and C. The dissociation of SF5CF3 was reduced if the system existed H2O, but it was independent of the amount of H2O. The rate coefficients were estimated to be 0.011s(-1) under moisture circumstance when the system total pressure was about 31 kPa. And the increase of the system pressure would cause exponential decrease of SF5CF3 dissociation. The reactive mechanism was argued based on the experiment results and the sinks of SF5CF3 under lightning (one of the discharge in the atmosphere) was estimated to be 53.6 kg x a(-1).