Highly efficient degradation of emerging contaminants by magnetic CuO@FexOy derived from natural mackinawite (FeS) in the presence of peroxymonosulfate

In this study, natural mackinawite (FeS), a chalcophilic mineral, was utilized to prepare iron/copper bimetallic oxides ([email protected]xOy) by displacement plating and calcination process. Various characterization methods prove that Cu0 is successfully coated on the surface of FeS, which were further oxidized to CuO, Fe3O4 and/or Fe2O3 during calcination process, respectively. [email protected]xOy performed highly efficient capacity to activate PMS for the degradation of various emerging pollutants including sulfamethoxazole (SMX), carbamazepine (CBZ), bisphenol A (BPA), 2,4-dichlorophenol (2,4-DCP) and diclofenac (DCF) in aqueous solution. Complete removal of the above pollutants was observed after 8 min of [email protected]xOy/PMS treatment. Taking SMX as an example, the key parameters including [email protected]xOy dosage, PMS dosage and initial pH were optimized. The results show that the catalytic system can be worked in a wide pH range (3.0-9.0). The quenching experiments and electron spin resonance (ESR) test demonstrated that the main reactive oxygen species in [email protected]xOy/PMS system were hydroxyl radicals (•OH) and sulfate radicals (SO4•¯), and SO4•¯ was the primary reactive species. Besides, the influence of coexisting anions (i.e., Cl¯, NO3¯, HCO3¯ and H2PO4¯) for the degradation of SMX was explored. [email protected]xOy/PMS system can maintain good catalytic activity and reusability in different water bodies and long-term running. This work provided a green strategy to fabricate the efficient catalyst in PMS-based advanced oxidation processes.