The electrical generation and oxidation efficiency of a novel bio-electro-Fenton system

Abstract

The inner portion of the reaction device of the bio-electro-Fenton (BEF) system was independently designed to construct dual-chamber bio-electro-Fenton systems to simultaneously degrade tetracycline (TC) and levofloxacin (LEV) in both anode and cathode chambers. The electro-Fenton reaction that degrades LEV wastewater in the cathode is propelled by bioelectric energy generated on-site. With graphite felt as the cathode and anode of the motional bio-electro-Fenton system, an external resistance of 10 Ω, pH of 3 in cathode, a Na2SO4 concentration of 0.07 mol/L, an Fe2+ concentration of 0.1 mmol/L and an aeration rate of 3 * 4.5 L/min, the removal rates of TC, COD, TOC, and NH4+-N within 72 h were 59.6 %, 83.7 %, 74.15 % and 80.1 % in the anode. And the LEV elimination rate was 75.50 % and the mineralisation rate was 68.39 % for 20 mg/L in the cathode within 24 h. The highest power density, current density, and voltage of the motional bio-electro-Fenton system could reach 7.12 W/m3, 636.94 mA/m3, and around 900 mV, respectively, and the maximum voltage could be maintained for over 36 h. Analyzing the system's electron transfer mechanism and proposing potential degradation pathways for tetracycline and levofloxacin.