摘要
In this study, the catalyst NiCo <sub>2</sub> O <sub>4</sub> /MnOOH was effectively synthesized by coating MnOOH nanorods with 1, 5, 10, and 20% NiCo <sub>2</sub> O <sub>4</sub> to activate peroxymonosulfate (PMS) and enhance the catalytic performance in breaking down the antibiotic ciprofloxacin (CIP). The result demonstrated that the 20% NiCo <sub>2</sub> O <sub>4</sub> /MnOOH + PMS system had the highest performance of CIP degradation. The CIP (20 μM) was degraded by 97.8% during 30-min reaction at 100 mg L <sup>−1</sup> of 20% NiCo <sub>2</sub> O <sub>4</sub> /MnOOH, and 200 μM PMS. The observed kinetic rate constants of prepared catalysts with PMS were in the order: 20% NiCo <sub>2</sub> O <sub>4</sub> /MnOOH (1.78 x10 <sup>−1</sup> min <sup>−1</sup> ) > 10% NiCo <sub>2</sub> O <sub>4</sub> /MnOOH (1.19 x10 <sup>−1</sup> min <sup>−1</sup> ) > 5% NiCo <sub>2</sub> O <sub>4</sub> /MnOOH (0.91 x10 <sup>−1</sup> min <sup>−1</sup> ) > 1% NiCo <sub>2</sub> O <sub>4</sub> /MnOOH (0.38 x10 <sup>−1</sup> min <sup>−1</sup> ) > MnOOH (0.27 x10 <sup>−1</sup> min <sup>−1</sup> ). Different operating parameters (solution pH, PMS concentration, catalyst amount, organic matter, and inorganic ions) were investigated to determine their impact on the degradation of CIP. Durability and reusability of catalyst for CIP degradation were examined. In addition, electron paramagnetic resonance (EPR) and scavenger test revealed the existence of sulfate radical (SO <sub>4</sub> <sup>•-</sup> ), hydroxyl radical (•OH), superoxide radical (O <sub>2</sub> •-), and singlet oxygen ( <sup>1</sup> O <sub>2</sub> ) that were involved in the degradation of CIP under NiCo <sub>2</sub> O <sub>4</sub> /MnOOH + PMS system.