Preparation Of Three-Dimensional Graphene Oxide And Its Removal Of Trichloroacetic Acid

With the rapid development of social economy and chemical enterprises,more and more refractory organic wastewater has been produced.In fact,if it cannot be treated quickly and effectively,it will cause serious harm to the water resources and environment which is scarce in China.People began to try a variety of advanced oxidation technology because traditional water treatment technologies cannot meet the increasingly stringent sewage treatment standards.As one of the most potential advanced oxidation technology,electric Fenton technology has attracted the attention of researchers at home and abroad.The development of highly efficient electrode materials is very important in the research of electric Fenton.Therefore,an efficient three-dimensional graphene oxide electrode was prepared by hydrothermal synthesis and acid activation strategy in this study.First of all,graphene oxide（GO）was prepared by the improved Hummers method,and then the three-dimensional graphene oxide composite electrode（T-3DGO）was successfully prepared by hydrothermal synthesis.Finally,the T-3DGO composite electrode was activated to obtain the T-3DGO（H）composite electrode.The morphology and structure of GO,T-3DGO composite electrode and T-3DGO（H）composite electrode were characterized by SEM,Raman,FT-IR and XRD.SEM images showed that the composite electrodes were mainly porous network structure,which can greatly improve the performance of the electrode due to conducive to the occurrence of mass transfer in the solution.FT-IR spectra showed that there were a large number of hydroxyl,carbonyl and other oxygen-containing functional groups on the surface of GO and T-3DGO composite electrodes.XRD results showed that the interlayer spacing of graphite increases from 0.34 nm to 0.73 nm.In conclusion,the characterization proved that the three-dimensional graphene oxide composite electrode needed for the experiment was successfully prepared.Using the prepared T-3DGO composite electrode as cathode and platinum wire as anode,an electro Fenton system was built to degrade trichloroacetic acid（TCA）.The effects of electrode activation time,Fe²⁺concentration,p H of the reaction system,current size and different initial concentrations of TCA on TCA degradation rate were studied.The TCA degradation reaction kinetics equation was fitted by change of TCA concentration in the single factor investigation process.The products in TCA degradation process were analyzed by liquid chromatography,and it was concluded that the intermediate products produced by electro Fenton degradation of TCA were mainly DCA,MCA and AA.On the basis of single factor effect on TCA degradation rate,through response surface analysis and experiments,the optimal reaction conditions were obtained:TCA initial concentration was 0.1 m M,reaction current was188 m A,electrode activation time was 66 mins,reaction p H was 3.2 and Fe²⁺concentration was 1.5m M.Under these conditions,TCA degradation rate was 96%.The prepared T-3DGO composite electrode was used instead of platinum wire as the anode of electro Fenton system to degrade TCA.The effects of single factor conditions on TCA degradation rate were investigated.The synergistic degradation system of electro Fenton cathode and anode was constructed by T-3DGO（H）composite electrode.T-3DGO（H）composite electrode was used as the cathode,the factors such as anode materials were investigated.The TCA removal rates were 99%,98%and 96%,respectively,when T-3DGO（H）composite electrode,carbon felt and platinum wire were used as anode electrode materials.