Preparation of Co-loaded carbon spherical shells capped with PVP and their Fenton-like degradation of rhodamine B

Sulfate radical-based advanced oxidation technologies (SR-AOPs) are extensively employed in the degradation of diverse wastewater pollutants owing to their superior capacity for degrading emerging and recalcitrant pollutants and their excellent adaptability. However, how to reduce the secondary pollution caused by metal ion spillage is still a major problem. In this work, Co 2+ was introduced into the molding process of SiO 2 microspheres as a novel activator of per-oxomonosulfate (PMS), which 15 mg of the catalyst completely degraded 100 mL of 40 mg/L of Rhodamine B (RhB) in 10 min, with a low Co leaching of only 0.18 mg/L. The effects of the introduction of Co, the addition of polyvinylpyrrolidone (PVP), H 2 O, and PMS, and the adjustment of pH, temperature, and anionic inorganics on the degradation of RhB were investigated. Based on the PMS activation mechanism analysis, it was concluded that the degradation of RhB involves two pathways, including the non-radical pathway dominated by 1 O 2 and mediated electron transfer and the radical pathway dominated by SO4 − , OH, and O2 − . This study presents a novel hybrid catalyst with high efficiency and easy recyclability, good recyclability, and low secondary pollution, which provides valuable insights into the field of wastewater treatment.