Magnetic Core-Shell-Structured FeOx/CN Catalyst Mediated Peroxymonosulfate Activation for Degradation of 2,4-Dichlorophenol via Non-Radical Pathway

In this study, a magnetic nano-FeOx/CN core-shell-structured catalyst with a high operating stability was successfully prepared by a coordinating polymer pyrolysis strategy. It exhibited high catalytic activity in peroxymonosulfate (PMS)-based advanced oxidation processes. Under neutral and room temperature conditions, the removal efficiency of 2,4-dichlorophenol (2,4-DCP) via FeOx/CN/PMS system reached more than 90% within 60 min, and the removal of total organic carbon reached 89% within 90 min. The key operating parameters were evaluated and analyzed. Besides, in five consecutive degradation experiments, FeO-3/CN showed high stability, low iron ion loss, and excellent magnetic separation and recovery performance, demonstrating its potential as a practical Fenton-like catalyst. The abundant and orderly N pores in the CN structure provided key conditions for the anchoring and dispersion of nano-FeOx particles. Electron paramagnetic resonance and free radical scavenging experiments proved that O-1(2) is the main reactive oxygen species (ROS) that causes 2,4-DCP degradation (about 76.4% of the total contribution). Combined with density functional theory, the degradation pathway of 2,4-DCP was reasonably predicted. This study provides new ideas for the design and synthesis of Fenton-like catalysts with high stability and high activity.

Automated summary

A magnetic nano-FeOx/CN core-shell-structured catalyst with high operating stability was successfully prepared in this study, showing excellent catalytic activity in PMS-based oxidation processes for 2,4-DCP degradation. It exhibited high stability, low iron ion loss, and excellent magnetic separation and recovery performance in consecutive degradation experiments. Experimental and theoretical studies revealed the main reactive oxygen species and degradation pathway of 2,4-DCP in the FeOx/CN/PMS system.