Removal of tetracycline by coupling of flow-through electro-Fenton and in-situ regenerative active carbon felt adsorption

Tetracycline (TC) was cost-effectively removed by coupling of flow-through electro-Fenton (EF) and in-situ regenerative active carbon felt (ACF) adsorption system, which used a modified graphite felt as the cathode. It proved the coupling process achieved a higher removal efficiency (5-44%) than single flow-through EF system and kept stable performance in 600 min treatment, contributed to the dynamic regeneration of ACF by utilizing the remaining oxidants from EF. Some important parameters such as current, initial pH, flow rate and initial TC concentration were optimized. For the TC of initial concentration of 50 mg/L, the TC removal efficiency reached above 90% with a low energy consumption of 48.6 kWh/(kgTOC) at the current of 80 mA and flow rate of 7 mL/min. This coupling process was not only more cost-effective than single flow-through EF, but also advantaged over wider adaption of pH range till 7, providing a more promising approach for organic pollutants removal.