The Comparative Study Of Repairing 2,4-Dichlorophenol-contaminated Soils From Biological And Physical Method

Chlorophenols are persistent organic pollutants which have high toxicity, and human being have always focused on its existence and controlling in environment. Biological and physical methods are used to repair the 2, 4-dichlorophenol (2, 4-DCP)-contaminated artificial soils and the effects of this two methods were compared in this reseach.White rot fungi have strong ability of decomposing aromatic compound, and the laccase they produced can make dechlorination of Chlorophenols and detoxication of organism. The typical white rot fungus Pleurotus ostreatus was selected as the object of bioremediation in this research and the best condition of degradation of 2, 4-dichlorophenol were fixed: temperature of 25℃, 40% of soil moisture, 0.4 mL bacteria liquid·per gram of dried soil of inoculation rate. The largest rate of 2, 4-DCP degradation and dechlorination was 84.56% and 98.07% within 18 days. Microwave radiation was selected as the physical method to repair the 2,4-dichlorophenol-contaminated artificial soils in this paper. The effect of microwave radiation technology of repairing 2, 4-dichlorophenol contaminated soil in the closed system was studied by using MnO₂ as an adsorbent. The results showed that it basically had no degradation effect of microwave radiation on 2, 4-dichlorophenol contaminated soil under the condition without MnO₂. The effect in the neutral condition was better than in the acidic condition with MnO₂. There was a certain effect of microwave radiation on 2, 4-dichlorophenol contaminated soil only under the neutral condition without MnO₂.The results also showed that the effect of bioremediation was better than physical methods compared with these two remediations, but the culture period of white rot fungi was long and bioremediation process was complicated. Researches of biotechnology of white rot fungi are mostly based on laboratories investigation, but its applying of industrialization is conditional. Microwave radiation is much easier than bioremediation and other physical or chemical remediation. Degradation of organic pollutant using microwave radiation will provide future research with some reference.