Abstract：A small amount of Fe-based catalyst anchored by NC-PC (three-dimensional porous carbon material) was prepared by a step-by-step thermal decomposition method, which was used to activate permonosulfate (PMS) to oxidize and degrade 2,4-dichlorophenoxyacetic acid (2,4-D) in water. The catalysts were characterized by transmission electron microscopy (TEM), fully automatic rapid surface measurement (BET), X-ray photoelectron spectroscopy (XPS) and inductively coupled plasma emission spectroscopy (ICP). The effects of different metals, preparation methods, catalyst dosage, PMS dosage, initial pH, and different anions (Cl-, NO3-, HCO3-) on the degradation of 2,4-D were investigated. Fe-NC-PC synthesized by thermal decomposition method has a better degradation effect on 2,4-D, when the initial concentration of 2,4-D was 0.1mmol/L, the initial pH=3.4, the catalyst was added When the amount was 0.15g/L and the PMS concentration was 0.7mmol/L, the 2,4-D removal rate can reach 91% within 20 minutes of reaction.With the increase of the dosage of catalyst and PMS, the degradation effect of 2,4-D increased; with the increase of initial pH, the degradation efficiency of 2,4-D gradually decreased; different anions in water (Cl-, NO3-, HCO3-) and humic acid (HA) has a slight inhibitory effect on the degradation of 2,4-D.Through radical quenching experiment, EPR test and XPS analysis of the main active species and reaction mechanism of the reaction, it was found that Fe-Nx formed during the material preparation process was the main reactive site, which can effectively activate PMS to degrade 2,4-D in water, 1O2 plays an important role in the degradation of 2,4-D.
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