Imidacloprid (IMI) removal by persulfate (PS) oxidation activated by ball-milled FeS₂/Fe0 composite was investigated in terms of reaction conditions and mechanisms. The ball-milled FeS₂/Fe⁰ with a mass ratio of 1:9 exhibited the highest activating efficiency for PS among the investigated mass ratios of 9:1, 4:1, 1:1, 1:4 and 1:9. Increasing dosages of ball-milled FeS₂/Fe⁰ and PS promoted IMI removal. At initial pH of 4.6 and initial IMI concentration of 0.15 mol/L, the optimal dosage of ball-milled FeS₂/Fe⁰ and PS were 0.1 g/L and 2.5 mmol/L, respectively, removing 99.8% of IMI after 60-min reaction. The ball-milled FeS₂/Fe⁰ could also activate PS effectively in a wide pH range from 3 to 9. Characterizations including Scanning electron microscopy with energy dispersive spectroscopy (SEM-EDS) and X-ray photoelectron spectroscopy (XPS) revealed that the high activation efficiency was related to FeS produced on Fe⁰ surface. Activation efficiency of PS was enhanced by accelerated electron transfer mediated by increased ferrous species, ultimately, the removal efficiency of IMI was improved. The released Fe²⁺ activated PS to generate SO₄^-·and ·OH. SO₄^-· was detected to be predominant reactive oxygen species in IMI degradation and three different pathways for IMI degradation were proposed. This study developed a efficient method to activate PS by FeS₂ modify Fe⁰ prepared by ball milling a mixture of Fe⁰ and FeS₂, which can provide some new insights into the degradation of organic pollutants.

研究了球磨FeS ₂ / Fe0复合材料活化过硫酸盐（PS）氧化去除吡虫啉（IMI）的反应条件和机理。质量比为1：9的球磨FeS ₂ / Fe ⁰对PS的活化效率最高，为9：1、4：1、1：1、1：4和1：9。球磨FeS ₂ / Fe ⁰和PS的剂量增加促进了IMI的去除。在初始pH值为4.6和IMI初始浓度为0.15  mol / L时，球磨FeS ₂ / Fe ⁰和PS的最佳剂量分别为0.1  g / L和2.5  mmol / L，在60-60 ℃后去除99.8％的IMI。分钟反应。球磨FeS₂ / Fe ⁰还可在3至9的宽pH范围内有效活化PS。表征包括扫描电子显微镜，能谱仪（SEM-EDS）和X射线光电子能谱（XPS）表明，高活化效率与在Fe ⁰表面产生的FeS 。通过增加亚铁物种介导的加速电子转移提高了PS的活化效率，最终提高了IMI的去除效率。释放的Fe ²⁺活化了PS，生成SO _4- ^·和·OH。SO _4- ^·被发现是IMI降解的主要活性氧种类，并提出了三种不同的IMI降解途径。这项研究开发了一种有效的方法，该方法可以通过FeS ₂改性通过球磨Fe ⁰和FeS ₂的混合物制备的Fe ⁰来活化PS ，这可以为降解有机污染物提供一些新的见解。