Treatment Of Organic Pollutants,Metal-organic Complexs By Electrochemistry

The electrochemical technology was widely used in the field of water treatment.Refractory organic pollutants and heavy metal in wastewater have been a major concern in the field of water pollution The conventional precipitation processes are limited for the removal of the pollutions.The previous work shows that the optimization of the process can be improved by the integration of different processes or the optimization of the reactor.Therefore,three kinds of electrochemical systems were constructed by the combination optimization of different processes and electrodes in this study.The removal efficiency of pollutants,the ability of recycling metals,the influencing factors and the reaction processes were investigated.1.A photoelectric catalytic system using TiO2/Ti and RuO2/Ti as bi-anode and activated carbon fiber(ACF)as cathode was designed,the electric anode can produce large amounts of O2,which can be reduced to H2O2.Under UV irradiation,H2O2 transformed to ·OH,which can enhance the photoelectric catalytic and electric catalytic oxidation process,and subsequently realizing the efficient removal of EDTA.The effects of current density,initial pH and dissolved oxygen on the degradation performance of EDTA were investigated.The mechanism of the degradation reaction and the energy consumption were analyzed.2.In this work,a photoelectrocatalytic reactor with a rotating cathode was designed for the destruction toward metal-EDTA complexes as well as the recovery of liberated metal ions on the surface of the rotating cathode.Firstly,the Cu-EDTA complex was selected as the targeted pollutant,the effect of cathode rotating speed,current density,initial pH and initial Cu-EDTA concentration on the the recovery of Cu2+ ions and destruction of Cu-EDTA were investigated.The efficiency of Cu recovery and Cu-EDTA destruction were improved to be over 40%at the rotating speed of 100 rpm within 120 min.The photoelectroctalytic reactor with the rotating cathode exhibited high destruction efficiency for metal-complexes and a high efficiency for the simutaneous recovery of liberated metal ions.3.The electro oxidation was introduced into the electrocoagulation process.The wastewater from an industrial of Bengbu City,Anhui Province was treated by three different methods:electrochemical oxidation,electric flocculation,electrochemical oxidation/electric flocculation.The effect of initial pH and current density was studied to the removal of COD and chroma.The results showed that the electrochemical oxidation/electric flocculation technology can effectively remove the refractory macro molecular organic matter in industrial wastewater in order to improve its biochemical degradation ability.The transformation of the organic was detected and the energy consumption was analyzed during the treatment.