Degradation of florfenicol in a flow-through electro-Fenton system enhanced by wood-derived block carbon(WBC)cathode

摘要

The flow-through electro-Fenton(EF-T)reactor with WBC cathode was designed to remove florfenicol(FF).The activated WBC cathode was prepared by facile carbonization and activation methods,and featured high specific surface area,natural multi-channel structure,abundant oxygen-containing groups,good hydrophilicity,and excellent O_(2)reducing capacity.WBC cathode was located above Ti/Ru-IrO_(2)mesh anode.O_(2)evolved at the anode was carried to the inner wall of channel of WBC by the force of buoyancy and water flow,which increases oxygen source of H_(2)O_(2)generation at the cathode.The flow-through system by using WBC electrode promote the mass transfer of O_(2)and FF.The production amount of H_(2)O_(2)at activated WBC was 32.2 mg/L,which was almost twice as much as that at non-activated WBC(15.0 mg/L).FF removal ratio in EF-T system was 98%,which was much higher than that of traditional flow-by electro-Fenton(EF-B,33%)or single electrooxidation system(EO,16%).EF-T system has the lowest energy consumption(4.367 kWh/kg)among the three electrochemical systems.The cathodic adsorption,anodic electrooxidation,and EF reaction are responsible for the degradation of FF.After five consecutive cycle experiments,FF removal ratio was still 98%,indicating WBC has the good stability.