NC-PC锚定微量Fe活化PMS降解水中2,4-二氯苯氧乙酸

采用分步热分解法制备了NC-PC（三维多孔碳材料）锚定的微量Fe基催化剂，用于活化过一硫酸盐（PMS）氧化降解水中2，4-二氯苯氧乙酸（2，4-D）.采用透射电子显微镜（TEM）、高精度比表面积仪（BET）、X射线光电子能谱分析（XPS）和电感耦合等离子体发射光谱分析（ICP）对催化剂进行表征.考察了不同金属、制备方法、催化剂投加量、PMS投加量、初始pH值以及水中不同阴离子（Cl^-、NO₃^-、HCO₃^-）对2，4-D降解的影响.结果表明，通过热分解法合成的Fe-NC-PC对2，4-D具有更好的降解效果，当2，4-D初始浓度为0.1mmol/L，初始pH=3.4，催化剂投加量0.15g/L，PMS浓度0.7mmol/L时，反应20min内2，4-D的去除率可达91%.随着催化剂投加量、PMS投加量的提高，2，4-D的降解效果提高；随着初始pH值的提高，2，4-D的降解效率逐渐降低；水中不同阴离子（Cl^-、NO₃^-、HCO₃^-）和腐殖酸（HA）对2，4-D的降解有轻微的抑制作用.通过自由基淬灭实验、EPR测试以及XPS分析了反应的主要活性物种和反应机理，发现材料制备过程中形成的Fe-N_x是主要的反应活性位，能够有效的活化PMS降解水中2，4-D，¹O₂在2，4-D的降解过程中起到主要作用.

NC-PC anchors trace Fe to activate PMS to degrade 2,4-dichlorophenoxyacetic acid in water

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-N_x 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.