Wu Deming, Ye Peng, Wang Manye, Wei Yi, Li Xiaoxia, Xu Aihua
School of Environmental Engineering, Wuhan Textile University, Wuhan 430200, PR China.
School of Chemistry and Chemical Engineering, Wuhan Textile University, Wuhan 430200, PR China.
J Hazard Mater. 2018 Jun 15;352:148-156. doi: 10.1016/j.jhazmat.2018.03.040. Epub 2018 Mar 21.
The activation of sulfite by heterogeneous catalysts displays a great potential in the development of new sulfate radials based technologies for wastewater treatment. Herein, cobalt nanoparticles embedded in N-doped carbon nanotubes (Co@NC) were prepared by a simple pyrolysis method. Due to the synergistic effects of the cobalt nanoparticles and N-doped carbon nanotubes, the Co@NC catalyst intrinsically shows an outstanding efficiency, excellent reusability and high stability in the catalytic oxidation of methyl orange (MO) in the presence of sulfite and dioxygen. The structure and efficiency of the catalyst was significantly affected by the content of cobalt and pyrolysis temperature. Several quenching experiments and electron paramagnetic resonance were carried out to investigate the catalytic mechanism. It is found that hydroxyl and sulfate radicals worked together to degrade MO in the system. The formation and decomposition of peroxymonosulfate may be an important route of these reactive radicals production. The effect of different anions, bicarbonate concentration, initial solution pH and dye types on the performance of the catalyst was also studied. This study can open a new approach for design and preparation of encapsulated cobalt in carbon materials as effective catalysts for pollutants degradation via sulfite activation.
通过非均相催化剂活化亚硫酸盐在开发基于新型硫酸根自由基的废水处理技术方面具有巨大潜力。在此，通过简单的热解方法制备了嵌入氮掺杂碳纳米管中的钴纳米颗粒（Co@NC）。由于钴纳米颗粒和氮掺杂碳纳米管的协同作用，Co@NC催化剂在亚硫酸盐和氧气存在下催化氧化甲基橙（MO）时，本质上表现出出色的效率、优异的可重复使用性和高稳定性。催化剂的结构和效率受到钴含量和热解温度的显著影响。进行了几项猝灭实验和电子顺磁共振研究催化机理。发现羟基自由基和硫酸根自由基共同作用降解体系中的MO。过一硫酸盐的形成和分解可能是这些活性自由基产生的重要途径。还研究了不同阴离子、碳酸氢盐浓度、初始溶液pH值和染料类型对催化剂性能的影响。本研究可为设计和制备碳材料包裹钴作为通过亚硫酸盐活化降解污染物的有效催化剂开辟新途径。
