Heterogeneous activation of persulfate by activated carbon supported iron for efficient amoxicillin degradation

Activated carbon supported iron (Fe-AC) was prepared as an efficient catalyst for activating persulfate (PS) to degrade amoxicillin (AMO). The complete degradation of AMO in Fe-AC/PS system was attained within 10 min. The AMO degradation efficiency increased as the initial catalyst dosage and PS concentration increased but was not affected by the initial pH. AMO degradation fitted the pseudo-first-order kinetic model, and the apparent activation energy was calculated to be 28.11 kJ.mol(-1) using the Arrhenius Equation. Both hydroxyl radical and sulfate radical were identified during AMO degradation by electron paramagnetic resonance spectroscopy and radical scavenger tests. The surface-adsorbed hydroxyl radicals played significant roles in AMO degradation. In addition, tests using ADPI_recA_lux bioreporter were performed to assess the degrees to which the solutions containing degraded AMO were toxic. The Fe-AC/PS system markedly decreased microorganism growth inhibition and genotoxicity caused by the solution containing degraded AMO, providing important information for applying Fe-AC/PS technology to application. (C) 2020 Elsevier B.V. All rights reserved.