Peroxymonosulfate activation by sponge-based FeS material for efficient degradation of tetracycline: The critical role of sponge

The effective control of antibiotic pollution in water has become an important issue in the field of environmental protection. In this study, the composite of iron sulfide and melamine sponge (FeS@MS) was successfully synthesized by in-situ synthesis method and applied to the oxidative removal of tetracycline (TC) in the presence of peroxymonosulfate (PMS). Under optimal conditions ([FeS@MS] = 0.1 g/L and [PMS] = 0.2 mM), 95.7% of TC was degraded in 5 min. The presence of NO 3 − , SO 4 2− , and Cl − slightly inhibited TC removal, whereas HPO 4 − had a certain promotion effect in activating PMS to degrade TC. The primary reactive oxygen species (ROS), including SO 4 − , OH , 1 O 2 , and O 2 − were identified through electron paramagnetic resonance (EPR) spectroscopy and radical quenching experiments. In addition, Fe 3+ in solution could react with FeS to produce Fe 2+ , which continuously activates PMS to generate radicals for TC degradation. The presence of MS reduced the agglomeration of FeS and played a protective role in the slow release of Fe 2+ . The degradation performance was further validated in real water matrices. This study provided new insight into fabricating functional material for the remediation of antibiotic wastewater. • A novel composite material (FeS@MS) was prepared for tetracycline degradation. • SO 4 − , OH, O 2 − and 1 O 2 were the main activated species during the process. • The sponge played a protective role in gradual releasing of Fe 2+ . • The performance of composite material in removing TCs was also validated in real water matrix.