Novel preparation of MOF derived Co(OH)2/ZnFe2O4 magnetic micro-nanoreactor with boost peroxymonosulfate activation for enhanced antibiotic contaminant oxidation

Abstract

Development of highly efficient and recyclable catalysts based on peroxymonosate (PMS) activation for the degradation of dangerous antibiotic contaminants was still a challenging topic. In this study, a highly efficient and recyclable heterogeneous Co(OH)2/ZnFe2O4 (Co-ZF) catalysts derived from metal-organic frameworks (MOFs) were prepared by a facile alkaline solution hydrothermal method, a high specific surface area (100.4 m2 g−1) and soft magnetic properties (Ms=25.3 emu g−1) composite material was obtained, and used for degrading norfloxacin (NOF) via PMS activation. The effects of temperature, alkali concentration, pH, initial NOF concentration, PMS and catalyst dosage on NOF degradation were discussed in detail. The results illustrated that the degradation rate of norfloxacin by the 3Co-ZF160 catalyst synthesized under 3 M NaOH and 160 ℃ hydrothermal conditions was 97.2%, after four consecutive cycles of degradation, the degradation rate of NOF by 3Co-ZF160 remained over 91% within 60 min. In contrast, the degradation rate of the Co3O4/ZnFe2O4 (CZF-600) catalyst calcined at 600 ℃ was only 74% available. Furthermore, The results of radical quenching suggested that OH•, SO4•−, SO5•− and 1O2 functioned in the presence of the Co(OH)2/ZnFe2O4-PMS system. Eventually, NOF degradation pathways were tentatively proposed on the basis presented via LC-MS. The above results highlight that the practical application of Co(OH)2/ZnFe2O4 heterogeneous catalyst in aqueous solution was of great significance.