| Chlorinated organic compounds are harmful and resistant to degradation. Most of the chlorinated organic compounds are toxic with the negative effects of"carcinogenesis, teratogenesis and mutagenesis". At the same time, many chloro-organic compounds are highly volatile and soluble as well as easily permealbe to skin, so they are dangerous in enviroment. So, industrial wastewater with high concention of chlorinated organic components heavily imperils human being's health and zoology enviroment seriously. It had been an obligatory duty to purify this kind of wastewater. At present, the mostly used routs to purify the wastewater containing chloro-organic compounds include the physical method, the biological method, chemical oxidation process and chemical reduction. The investigations for a mature and economically process to deal with the chlorinated-wastewater are of importante meaning and are still under way.In the present work, the foundation research work as well as application exploring aimed to the dechloridation and degradation of the industry wastewater was carried out. The sample of wastewater was taken from a Chemical plant in Chongqing and it was formed in the dichloroprene producing process, so called neoprene wastewater. The compositon of this chlorinated hydrocarbon wastewater is as follows, NaCl (30%), water (55～60%), wood tars, N-nitroso diphenylamine, tetrachloridebutane, pentachlorobutane, chlorinated compounds (5～10%) including dichlorbutene, trichlorobutene, dichloroprene, etc. It is oringinal a mixture with pH of 10-11, CODCr concentration of 32214.2 mg/L and with stongly odour. The goal of the present work is to deodour and reduce COD concentration. Regarding this neoprene wastewater, the foundation research work of a route combine with bi-metal reducing method and Fenton oxidation method was investigated. A novel route of bimetal reducing method incorporated with Fenton oxidation method for the dechloridation and the reducing COD values was established here. The dechloridation for deodour and the degradation of COD were simultaneously relized with this combined route.Experiments were carried out to explore the factors associated with the COD removal ratio and deodoration by the combined process of bimetals reduction and Fenton oxidation. The feasible process was obtained by the purification of chlorinated hydrocarbon from the aspects of amount of bimetals, dosage of FeSO4 and H2O2 at various pH value. Results showed that the zero valent iron powder can have good performance in dechloridation and Fenton reagent can oxidize organics to remove COD. The satisfactory results were obtained by the following operation conditions. The pH value was adjusted to 5～7 by HCl and the zero valent iron and zinc powder were 0.5～1.0wt%, respectively. Then 0.5～1.0 wt% FeSO4 was put in the reactant followed by dropping in 20～30 wt% H2O2 gradually. Molar ratio of H2O2 to iron is in the range of 4～6 at optimal reaction temperature 60～80℃. The good purification performance was achieved with malodor removal and residual COD concentration 800 mg/L.The research work indicate that the route of bimetal reducing method combined with Fenton oxidation method can removel the chlorine from the chlorinated hydrocarbons mixture and reducing COD values by Fenton oxidation. This pilot study provides theory and basic data for the industry applications of treatment of neoprene wastewater. Further more, it also provide an new route for the treatment and purification of high concentration chlorinated organic wastewater.
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