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This the papers selected nitrobenzene substance (p-nitrotoluene, m-nitrotoluene) and dye Reactive Yellow 84 as the target reactant studied various reaction conditions (pH, initial concentration, temperature, ozone dosage, ultrasonic density) of ozone Ultrasound (U.S. / O 3 ) in aqueous solution degradation efficiency, as well as to explore the possible degradation mechanism. -Nitrotoluene' dissertation">Nitrotoluene (PNT) and nitrotoluene (MNT) degradation experiments, the two substances degradation of pseudo first-order kinetics. pH = 10.0 when U.S. / O 3 oxidation system of maximum degradation efficiency. The initial concentration of the reduced anti-degradation efficiency. The role of temperature and ozone dosage on the degradation efficiency exist. Separate Ozone (O , 3 ), a separate ultrasound (U.S.) and U.S. / O 3 respective system the PNT solution, total organic carbon (TOC) removal rates were 68%, 8 % and 85%, MNT solution TOC removal were 41%, 9% and 56%. As can be seen, the U.S. / O 3 oxidation system in the removal of TOC than separate O 3 or a separate U.S. more effectively. In this thesis, the the MNT reaction mixture toxicity with U.S. / O 3 reaction time trends and the corresponding degradation intermediates, indicating that the US / O 3 in the removal of TOC At the same time, can effectively reduce the toxicity of the mixture of MNT. Meanwhile, according to gas chromatography / mass spectrometry (GC / MS) determination of reaction intermediates, the present study also suggested the possible degradation pathways of nitro toluene and nitrotoluene. In this thesis, Reactive Yellow 84 (RY84) US / O 3 oxidation system of reaction conditions were investigated and mineralization study the mechanism. Separate O 3 , a separate U.S. and U.S. / O 3 system, remove the the TOC proposed a degradation reaction rate constant of 7.3 × 10 - 3 min -1 , 9.0 × 10 -4 min -1 and 1.8 × 10 - 2 min -1 , Description U.S. / O 3 oxidation system has a ratio separate O 3 or a separate US better degradation efficiency . Solution pH = 5.0, for 4.5 g / L ozone dosage, ultrasonic density 1 76W / L and RY84 solution of the initial concentration of 100mg / L, the mineralization of the entire system to achieve the optimal value. Binding in the reaction process in a variety of small molecular organic and inorganic ions (oxalic acid, formic acid, acetic acid, no 3 - the NO 2 < sup> - , NH 4 , Cl - and SO 4 2 - < GC / MS measurement result of quantitative determination / sup>), ion chromatography (IC) and other organic intermediate products, to RY84 Degradation possibility mechanism.
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