The oxidation efficiency and the microbial community analysis of a novel bio-electro-Fenton system with Fe@Co/GF composite cathode

Abstract

A dual-chamber motional bio-electro-Fenton (BEF) system with Fe@Co/GF as the cathode was constructed to simultaneously degrade levofloxacin and tetracycline wastewater in both cathode and anode chambers. With an external resistance of 10 Ω, an initial cathode pH of 3, a Na2SO4 concentration of 0.5 mol/L, an initial Fe2+ concentration of 0.01 mmol/L, an aeration rate of 3*4.5 L/min, an initial levofloxacin concentration of 20 mg/L in the cathode chamber, and an initial tetracycline concentration of 20 mg/L in the anode chamber, the total levofloxacin removal rate was 91.09 % and the total mineralisation rate was 90.47 % within 24 h when Fe@Co/GF was used as the BEF system's cathode. And the total removal rates of tetracycline, COD and TOC in the anode chamber were 64.54 %, 85.45 % and 75.12 % respectively within 72 h. The BEF system's maximum power density, current density, and voltage were 12.64 W/m3, 636.94 mA/m3, and 920 mV, respectively. Furthermore, high-throughput sequencing techniques were used to examine the microbial flora that was valuable in the BEF system. This study's BEF system was capable of long-term stability and has enormous potential for treating antibiotic effluent.