MnFe2O4 nanoparticles promoted electrochemical oxidation coupling with persulfate activation for tetracycline degradation

Abstract To enhance the performance of electrochemical oxidation (EO), MnFe2O4 nanoparticles was synthesized and added to the EO system with persulfate (PS) for the tetracycline (TC) degradation. The MnFe2O4 could not only be the catalyst, but also act as the three-dimensional electrode in the electrocatalysis, improving the PS activation and TC elimination. The fabricated nanomaterial was examined through X-ray diffraction, scanning electron microscopy, N2 adsorption isotherms, and X-ray photoelectron spectroscopy to explore its crystal structure, surface morphology, pore structure, and element valences, respectively. The EO/PS-MnFe2O4 system achieved 86.23% TC removal after 60 min treatment, verifying that the synergy had an excellent ability for the TC decontamination compared with other controlled tests. The effect of experimental parameters (MnFe2O4 dose, current density, PS dosage, and original pH) on the TC elimination was determined, and the catalyst displayed a favorable stability and recyclability in consecutive five cycles. The scavenging examination result proved that sulfate and hydroxyl radicals both worked for the antibiotic removal. The possible decomposition pathway was proposed based on the determination of high-performance liquid chromatography mass spectrometer for the TC degradation intermediates.