Studies On The Oxidation Degradationand Of Three Pesticides By The Ammonium Persulfate Combination With Catalysts

Persulfate oxidation is one of the most potential technology, especially to persistent organic pollutant which were hard to be degraded. Persulfate can be thermally or chemically activated to produce a powerful oxidant sulfate free radical (SO4-,E0～2.6V)which can potentially destory many organic contaminants such as Methyl parathion, Carbofuran and Carbaryl. The study of activation method is a hot issue. The conventional activation methods consist of heat, UV and metal activation. While some new activation method come forthrecently. In this study, a Methyl parathion, Carbofuran and Carbaryl were chosen as the model contamination to study the degradation rate,influential factor and radical method under heat and metal activation (conventional activation method) and pH.This paper main research conclusions were as follows:(1) Activating persulfate and then used for Methyl parathion, Carbofuran and Carbaryl degradation was developed. Increasing persulfate concentration can enhance degradation rate constant.(2) Under the conditions of40℃and0.05mol L-1persulfate, removal of Methyl parathion and Carbofuran were observed within24h, the degradation rate can be above90%.But for Carbaryl, the degradation rate is about70%, below Methyl parathion and Carbofuran. Increasing temperature can enhance degradation rate constant, Under the conditions of50℃, the rseults that hot activate persulfate effectively.(3) when using metal (Fe2+、Fe3+、Fe304and MnO2) activate persulfate,the degradation rate of Methyl parathion, Carbofuran and Carbaryl were better than only persulfate dealing pesticide. Effect of Fe3O4is weaker than two types of iron ion, but Fe3O4can be reuse for3-4times, more environmentally friendly and economy.