Biochar supported magnetic ZIF-67 derivatives activated peroxymonosulfate for the degradation of ciprofloxacin: Radical and nonradical pathways

Developing highly efficient and reusable heterogeneous catalysts is the key to achieve peroxymonosulfate (PMS) activation for pollution degradation. Herein, a novel magnetically recoverable composite catalyst BC/CoNC derived from ZIF-67 and peanut shell was designed and applied for peroxymonosulfate (PMS) activation to degrade Ciprofloxacin (CIP). The results of structural characterization showed that ZIF-67 derived CoNC was uniformly distributed on peanut shell biochar and there was no obvious agglomeration. The 1.0-BC/CoNC exhibited the optimal removal efficiency, CIP was degraded by 95.9% within 30 min, and the removal efficiency of TOC was 42.0%. In the meantime, the catalyst demonstrated a high PMS activation capacity over a wide pH range of 3-11. Both electron paramagnetic resonance (EPR) studies and radical quenching experiments revealed that SO4 center dot-, center dot OH, O-2(center dot-) and O-1(2) were involved in the degradation of CIP. In addition, the 1.0-BC/CoNC/PMS system can effectively degrade different pollutants in water, and the potential application for the degradation of CIP in actual water samples (the tap water and lake water) were also investigated. This work proposes new ideas for the preparation of low-cost biomass/MOFs derived catalysts for the application of water treatment.

Automated summary

In this study, a novel magnetically recoverable composite catalyst BC/CoNC derived from ZIF-67 and peanut shell was designed and applied for the activation of peroxymonosulfate (PMS) to degrade Ciprofloxacin (CIP). The results showed that the catalyst exhibited excellent removal efficiency and wide application potential, effectively degrading CIP in different water samples.