Bio-Electron-Fenton (BEF) process driven by sediment microbial fuel cells (SMFCs) for antibiotics desorption and...

A sediment microbial fuel cell electro-Fenton (SMFC-E-Fenton) system was proposed in this study by utilizing the biological electrons produced from an SMFC to power an E-Fenton process. Antibiotics with different absorbability in both aqueous and solid phase can be removed by this system at room temperature and pressure condition, without external power or other chemical reagents. γ-FeOOH graphene polyacrylamide carbonized aerogel (γ-FeOOH GPCA) with high electrochemically active surface area (EASA), good conductivity and stable electrochemical activity were used as the cathode. After 40 h treatment, the total degradation rate of sulfamethoxazole (SMX) and norfloxacin (NOR) were 97.4 ± 2.9% and 96.1 ± 3.0%, respectively. Compared with the sludge digestion system, the residual SMX and NOR in sludge declined from 10.2 ± 1.5% to 1.1 ± 1.2% and from 31.3 ± 1.8% to 3.1 ± 1.3%, respectively. The E-Fenton process can also promote electricity production and sludge reduction efficiency of SMFC, as the maximum power density SMFC-E-Fenton system reached 472.21 ± 11.5 mW m^-2 and 431.39 ± 15.6 mWm^-2, respectively. 6.2 ± 0.3% and 5.7 ± 0.8% of the initial sludge was reduced while treating SMX and NOR.