| Nitrobenzene wastewater pollution has already become a global environmental problem. The groundwater pollution by nitrobenzene has become increasingly serious, and already been the concern and attention to domestic and foreign scholars at present. Nitrobenzene has the following characteristics such as:highly toxicity, stable chemical properties, highly polluting,difficult to be biodegradable, and the pollution has lasted for a long time. Whether nitrobenzene into water or air. it could cause large damage to environment and human. Therefore, we must pay more attention to groundwater pollution problems by nitrobenzene. At present, the research of groundwater pollution by nitrobenzene is still in the initial stage. So the problem of groundwater pollution by nitrobenzene still needs to be further studied.The purpose of this study was expected to remove the high nitrobenzene of groundwater. with the methods of NF. Chemical oxidation and Activated carbon adsorption. Besides, the research was also investigated, looking forward to providing theory basis in groundwater pollution by nitrobenzene. Permeate and concentrated liquid had been separated and the effects of four main factors including influent concentration, flow, pH and temperature were studied by using NF process. Selection of optimum condition for NF process, which was the influent.600mg/L: concentration.60L/h:pH.8:temperature.50℃. The rejection could reach 64.15% with the actual polluted groundwater by the cyclical NF process. The results showed that NF could reject nitrobenzene effectively, and could provide necessary condition for removing nitrobenzene.Chemical oxidation had been used to treat the concentrated liquid of nitrobenzene. The effect of main factors on oxidization of Fenton reagent was observed by orthogonal experiment. The optimal condition was the reaction time. 60min; pH.3;concentrate of H2O3.800mg/L:concentrate of Fe2+,160mg/L. in which the conversion rate was relatively low at the beginning, and then increased gradually. The conversion rate could reach 97% and could stay a stabile level after 60 minutes. The results showed that it had good treatment efficiency of nitrobenzene with the method of Fenton reagent.Comparison of Fenton reagent. ozone oxidation had been used to treat the concentrated liquid of nitrobenzene. The optimal condition of main factors was pH. 10;temperature,50℃:flow of O3,400h/L, in which the conversion rate increased gradually. The highest conversion rate could reach 40.06% and could stay a stabile level after 10 minutes with the conversion rate of more than 37%. In order to improve the treatment effect of concentrated liquid of nitrobenzene, H2O2 had been used as the catalyst in the ozone oxidation process. The optimal condition of main factors was pH. 10:temperature,50℃;flow of O3,300h/L; dosage of H2O2,15mg/L, in which the conversion rate increased gradually and could reach 91.94% after 25 minutes. The conversion rate was increased obviously with the ozone oxidation process when the H2O2 was the catalyst. H2O2 and ozone oxidation in combination could remove nitrobenzene better than ozone oxidation process.Activated carbon adsorption had been used to treat the permeate liquid of nitrobenzene because of the large adsorption capacity and specific surface area. With the increasing dosage of activated carbon, the removal rate had become lower. The removal rate of nitrobenzene was 99.31% and the concentration was 1.3188mg/L when the dosage was 100mg/L. The removal rate of nitrobenzene was 98.87% and the concentration was 2.1783mg/L when the dosage was 50mg/L. The optimum dosage was 50mg/L because of the rest concentration of nitrobenzene and economic considerations. The main adsorption occurred in 60 minutes, and the adsorption capacity had increased with the reaction time. The data were fitted to pseudo-second order kinetic model. and R2 was 0.9999. So the adsorption process could be described with the pseudo-second order kinetic model. The results showed that nitrobenzene had been adsorbed very well by activated carbon adsorption, and it had certain practical significance and engineering significance for the governance of nitrobenzene wastewater.In a word, the method of NF-Chemical oxidation-Activated carbon adsorption was ssuccessfully used to treat nitrobenzene of groundwater and had high removal rate by this experiment. It will have big engineering significance in wastewater treatment in the future.
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