Rapid microwave synthesis of Fe3O4-PVP@ZIF-67 as highly effective peroxymonosulfate catalyst for degradation of bisphenol F and its mechanism analysis

Abstract

Various metal-based heterogeneous catalysts activated peroxymonosulfate for organic pollutants degradation are increasingly recognized as an environmentally important sewage treatment technology. In this study, polyvinyl pyrrolidone (PVP) modified Fe3O4 loaded ZIF-67 magnetic catalyst with transition metal cobalt ion was prepared for the first time by microwave-assisted solvothermal (MS) method within 30 min to activate peroxymonosulfate. The microwave synthesis process changed the time-consuming shortcoming of conventional method. The catalytic activity of the synthesized Fe3O4-PVP@ZIF-67 was assessed on bisphenol F (BPF) removal. The result showed 99.8% BPF was removed under the conditions of catalyst content of 0.15 g·L−1, PMS content of 0.3 mM, and pH without adjustment in 60 min. And the Fe3O4-PVP@ZIF-67/PMS system exhibited a quality catalytic performance when the solution pH of BPF varied from 3 to 11. Compared with humic acid (HA), inorganic anions (Cl−, H2PO4−, SO42−, HCO3−, and CO32−) showed slight effect to the degradation system. The quenching experiment verified that the main active substance in this system was SO4−•. Based on the degradation intermediates identified by gas chromatography-mass spectrometer (GC–MS), the main degradation pathways were proposed for the degradation of BPF. Overall, Fe3O4-PVP@ZIF-67 as PMS activator is promising catalyst for sulfate radical-based wastewater treatment.