Study On The Efficiency And Conditions Of Treatment Of Mtbe Polluted Water By Electro-Fenton Process

As the main gasoline antiknock agent,MTBE accounts for about 10%to 15%of gasoline content,and it enters the environment in various ways with the leakage and combustion of oil.MTBE is toxic to the environment.The pollution of MTBE is persistent due to its good mobility,stable physical and chemical properties.In this study,the pollution of water by MTBE was applied to repair the polluted water body by electro-Fenton process.The efficiency and influence conditions of the treatment were investigated,which showed that the repair effect of this technology was excellent.In this study,an iron plate was used as a cathode,the oxygen-depleted MMO anode was used as an anode.The cathode can be chemically corroded under acidic conditions to generateFe²⁺.The anode is an oxygen evolution anode,which can promote the formation of H ₂O ₂,so that the electro-Fenton reaction can be efficiently conducted,and the cathode can be effectively protected.The electrodes’comprehensive performance was outstanding.This study designed the response surface test with Design Expert software.The effects of initial concentration of MTBE,current density,plate spacing and pH on the performance of the electro-Fenton system were investigated.In the research range,when the initial concentration of MTBE is low,the current density is strong,the plate spacing is wide and placed in an acidic environment,the removal rate is effectively increased,and the order of influence degree from strong to weak is MTBE initial concentration>current density>plate spacing>pH.In this study,2FI mathematical model with good reliability was selected to predict and verify the MTBE removal rate.According to the influence of each condition,the single variable experiment was conducted in turn,and the optimal degradation conditions of the system were as follows:the initial concentration was 8 mg/L,the pH was 3,the electric current density was 30.5 mA/cm²,the plate spacing was 120 mm.Then the result illustrates that MTBE removal rate is up to 96.94%,and the COD_Crr removal rate is up to 79.33%.In addition,the changes of ORP,DO,concentration ofFe²⁺and total iron,and pH were used as evaluation indexes to reflect the operation efficiency of the electro-Fenton system.As the reaction proceeds,the solution rapidly develops a strong oxidizing environment with an ORP of up to 423 mV.The pH can keep around optimal conditions;DO and concentration ofFe²⁺and total iron accumulated rapidly,promoting the generation of OH.In addition,air supply also has an important impact on the reaction.When there is no air supply,the removal rate of both MTBE and COD_Cr is substantially reduced.In this study,no additional chemical reagents are needed,which means the process is environmentally friendly,the equipment is simple,the footprint is small,and easy to operate.In conclusion,the electro-Fenton system applying to treat MTBE-polluted water is stable and with high efficiency.