College of Chemical Engineering, Beijing University of Chemical Technology, Beijing, 100029, PR China; Chinese Research Academy of Environmental Sciences, Beijing, 100012, PR China.
Beijing Municipal Research Institute of Environmental Protection, Beijing, 100037, PR China.
Chemosphere. 2021 Apr;269:128740. doi: 10.1016/j.chemosphere.2020.128740. Epub 2020 Oct 26.
In this study, bamboo-shaped carbon nanotubes exhibiting high nitrogen content and Ni encapsulation (Ni@NCNT) were effectively synthesized by a simple pyrolysis method. The catalytic peroxydisulfate activation for cephalexin (CPX) degradation was investigated using the prepared material. SnO was further decorated and fabricated on the anode material (SnO/Ni@NCNT) for electrochemical degradation of CPX in an aqueous solution. Transmission electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy indicated that the SnO nanoparticles were uniformly distributed on the surface of Ni@NCNT. Electrochemical characterization employing cyclic voltammetry and linear sweep voltammetry demonstrated that SnO/Ni@NCNT displayed higher oxygen evolution potential and electrocatalytic activity than Ni@NCNT. Mineralization of CPX in wastewater was performed using electrolysis coupled with persulfate oxidation. The analysis revealed a synergistic strengthening effect. The electropersulfate oxidation resulted in higher total organic carbon (TOC) removal (70.3%) than the sum of electrooxidation (48.1%) and persulfate oxidation (9.2%) toward CPX. This phenomenon might result from the regeneration of sulfate radicals (SO) on the anode and complementary oxidation by SO and OH. Persulfate oxidation alone was shown to result in low TOC removal, although CPX was mostly degraded. Additionally, the CPX degradation pathway involving electropersulfate oxidation was proposed and it is indicated that CPX molecules were completed decomposed by the examination of short chain acids, mineralized ions, and ecotoxicity evolution indicated that the antibiotic was completely degraded. This study provides a new approach for the design and preparation of novel electrode materials and electrochemical degradation facilities for the removal of pollutants via persulfate activation.
在这项研究中，通过简单的热解法成功合成了具有高氮含量和 Ni 封装的竹状碳纳米管（Ni@NCNT）。使用所制备的材料研究了催化过一硫酸盐对头孢氨苄（CPX）降解的活化作用。进一步在阳极材料（SnO/Ni@NCNT）上修饰和制备了 SnO，以在水溶液中电化学降解 CPX。透射电子显微镜、X 射线衍射和 X 射线光电子能谱表明，SnO 纳米颗粒均匀分布在 Ni@NCNT 的表面上。循环伏安法和线性扫描伏安法的电化学表征表明，SnO/Ni@NCNT 比 Ni@NCNT 具有更高的析氧电位和电催化活性。通过电解析出过硫酸盐氧化法对废水进行 CPX 矿化。分析表明存在协同强化效应。与电氧化（48.1%）和过硫酸盐氧化（9.2%）相比，电过硫酸盐氧化导致 CPX 的总有机碳（TOC）去除率（70.3%）更高。这种现象可能是由于阳极上硫酸根自由基（SO）的再生和 SO 和 OH 的补充氧化所致。尽管 CPX 大部分被降解，但单独的过硫酸盐氧化导致 TOC 去除率较低。此外，提出了涉及电过硫酸盐氧化的 CPX 降解途径，并通过考察短链酸、矿化离子和生态毒性演变表明，抗生素已完全降解。该研究为设计和制备新型电极材料以及通过过硫酸盐活化去除污染物的电化学降解设备提供了新方法。
