Department of Environmental Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, PR China; National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing, 100124, PR China.
Department of Environmental Engineering, Faculty of Environment and Life, Beijing University of Technology, Beijing, 100124, PR China; National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing, 100124, PR China.
Chemosphere. 2022 Dec;308(Pt 1):136291. doi: 10.1016/j.chemosphere.2022.136291. Epub 2022 Sep 1.
Developing highly efficient, stable, recyclable, and application value heterogeneous catalysts in advanced oxidation processes has essential application value in the degradation of refractory pollutants. In this paper, the CoNi alloy anchored onto N-doped porous carbon (CoNi-600@NC) catalyst was prepared using bimetallic doped metal-organic frameworks as precursors. The magnetic CoNi-600@NC can activate peroxymonosulfate (PMS) to degrade sulfamethoxazole (SMX). Therefore, SMX can be removed 100% within 25 min. CoNi-600@NC/PMS has a broad pH (3-9) application range, good applicability, and repeatability. Radical quenching, quantitative and electrochemical experiments proved that the degradation of SMX was dominated by free radical (Superoxide anions) and non-free radical pathways (surface-bound radicals). Mechanistic analysis showed that the interaction between Co-N/pyridine N-sites and graphitized carbon with PMS induced the formation of surface-bound active species. Moreover, CoNi nanoparticles promoted the redox cycle of metals. The synergistic catalytic mechanisms between the CoNi alloy and the abundant functional groups gave CoNi-600@NC excellent catalytic properties and applicability. Using density functional theory predicted the reaction sites of SMX and proposed four degradation pathways. The toxicity of intermediates was comprehensively evaluated. In addition, a CoNi-600@NC continuous flow reactor was constructed with a daily treatment capacity of 45 L and 100% SMX removal. This study expands the application of persulfate advanced oxidation technology by synthesizing recyclable magnetic catalysts and provides new synergistic degradation mechanisms for removing refractory organics.
在高级氧化过程中开发高效、稳定、可回收且具有应用价值的异相催化剂，对于难降解污染物的降解具有重要的应用价值。本文以双金属掺杂金属有机骨架为前驱体制备了负载在氮掺杂多孔碳上的 CoNi 合金（CoNi-600@NC）催化剂。该磁性 CoNi-600@NC 可以活化过一硫酸盐（PMS）来降解磺胺甲恶唑（SMX）。因此，SMX 可以在 25 分钟内被完全去除。CoNi-600@NC/PMS 具有较宽的 pH（3-9）应用范围、良好的适用性和可重复性。自由基猝灭、定量和电化学实验证明，SMX 的降解主要由自由基（超氧阴离子）和非自由基途径（表面结合自由基）控制。机理分析表明，Co-N/pyridine N 位与石墨化碳与 PMS 的相互作用诱导了表面结合活性物种的形成。此外，CoNi 纳米粒子促进了金属的氧化还原循环。CoNi 合金与丰富的官能团之间的协同催化机制赋予了 CoNi-600@NC 优异的催化性能和适用性。利用密度泛函理论预测了 SMX 的反应位点，并提出了四种降解途径。对中间产物的毒性进行了综合评价。此外，构建了 CoNi-600@NC 连续流动反应器，其日处理能力为 45 L，SMX 的去除率为 100%。本研究通过合成可回收的磁性催化剂扩展了过硫酸盐高级氧化技术的应用，并为去除难降解有机物提供了新的协同降解机制。
