[Treatment of dichlorvos by ozone oxidation]

The dichlorvos of organophosphates was oxidized by ozone in a reactor of 12 L, when its initial concentrations was 30 mg/L, ozone concentrations was 4.9, 6.7 and 7.6 mg/L, pH was 3.1, 5.3, 7.2, 9.4, 11.2 and temperature was 10-50 degrees C, and the reaction kinetics of the treatment of dichlorvos by ozone were discussed. The results show that ozonation is an efficient way for treating dichlorvos. The removals of dichlorvos are all over 96% in 5 min ozonation. When ozone concentration is 6.7 mg/L, mineralization rate in TOC reaches 34.8% in 4 min. The degradation rate of dichlorvos increases as the ozone concentration increases but descends as its initial concentration increases. The removal effect of dichlorvos is roughly independent of pH value and temperature. When ozone concentration is 6.7 mg/L at pH 7.2 in room temperature, the ozonation reaction order of dichlorvos is about 0.11 and the reaction rate constant is 7.72 mg x (L x min)(-1).