Characteristic Study On The Degradation Of 2,4,6-TCP By Microbial Electrochemical Coupled System

With the rapid development of medicine,paper and other industries,chlorophenols have been continuously produced,such substances will inevitably enter the water environment.Chlorophenols is toxic and may lead to mutagenesis,carcinogenesis or teratogenesis,but it is difficult for water to self-purify through itself.Therefore,it is a serious threat to the ecological environment of the earth,also aroused the concern of the majority of researchers.The traditional physical method,chemical method and biological method have disadvantages such as can use secondary pollution or pertinence is not strong and so on.Therefore,it is of great significance to establish a new and effective method to treat this kind of refractory organic wastewater.In this paper,the microbial electrolysis cell(MEC)which in the electrochemical cell system(BES),was used to treat the wastewater containing 2,4,6-three(2,4,6-TCP),the wastewater was first reduced by biological cathode,and after a period of time,then transferred to the biological anode,which can degradate by oxidation.This paper intend to find a new method to treat the chlorophenol wastewater.The main results are as follows:(1)Biological cathode capable of reducing degradation of 2,4,6-TCP and biological anode with oxidation on 2,4,6-TCP and its intermediate product was successfully prepared.And microbial electrochemical system was successfully activated.(2)The main factors affecting the degradation of 2,4,6-TCP were determined by orthogonal experiments,the results were as follows: applied voltage >initial pH>the initial concentration of 2,4,6-TCP>the initial concentration of C6H12O6 in cathode.(3)Through single factor experiments,the experimental conditions were optimized,and it was found that when the applied voltage was 0.7V,initial pH=7.0,the initial concentration of 2,4,6-TCP was 20mg/L,the degradation for 72 h,2,4,6-TCP can be completely degraded.(4)By comparing the electrochemical method,anaerobic biological method and electrochemical microbial coupled method,it was found that the effect of removal rate of 2,4,6-TCP by electrochemical microbial coupled method was better than that of solo electrochemical method or solo anaerobic biological method.(5)HPLC and HPLC/MS were used to determine the degradation of the waste water.It was found that the degradation pathway of 2,4,6-TCP was mainly reductive dechlorination in the cathodic reduction under the effect of dechlorination firstly,then liquid transfer to the anode cathode after generation of polyphenols in oxidation,further reduce chemical benzene ring opening,can continue to generate small molecule acid in anodic oxidation,the final part was mineralized into CO2 and H2 O.