Highly efficient activation of peroxymonosulfate by biomass juncus derived carbon decorated with cobalt nanoparticles for the degradation of ofloxacin.

The cobalt nanoparticles decorated biomass Juncus derived carbon (Co@JDC) was prepared by facile calcination strategy and applied to activate peroxymonosulfate (PMS) for eliminating ofloxacin (OFX) in the water environment. The results of catalytic experiments show that 97% of OFX degradation efficiency and 70.4% of chemical oxygen demand removal rate are obtained within 24 min at 0.1 g L Co@JDC, 0.2 g L PMS, 20 mg L OFX (100 mL), and pH = 7, which indicates that Co@JDC/PMS system exhibits excellent performance. Meanwhile, the experimental results of affect factor show that Co@JDC/PMS system can operate in a wider pH range (3-9) and Cl, NO, and SO have an ignorable effect on OFX degradation. The radical identification experiments confirm that SO˙, ·OH, O˙, and O are involved in the process of PMS activation, especially SO˙ and O are the main contributors. Furthermore, a possible PMS activation mechanism by Co@JDC was proposed and the degradation pathways of OFX were deduced. Finally, the stable catalytic activity, negligible leaching of Co, and the outstanding degradation efficiency for other antibiotics prove that Co@JDC possesses good stability and universality.