Acta Chim. Sinica ›› 2017, Vol. 75 ›› Issue (6): 538-543.DOI: 10.6023/A17020047 Previous Articles     Next Articles

Special Issue: 铁环境化学

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纳米零价铁活化分子氧原理及降解有机污染物性能增强策略

穆毅, 贾法龙, 艾智慧, 张礼知   

  1. 农药与化学生物学教育部重点实验室 环境与应用化学研究所 华中师范大学 武汉 430079
  • 投稿日期:2017-02-10 发布日期:2017-04-01
  • 通讯作者: 艾智慧, 张礼知 E-mail:jennifer.ai@mail.ccnu.edu.cn;zhanglz@mail.ccnu.edu.cn
  • 基金资助:

    项目受国家重点研发计划纳米科技专项(2016YFA0203000),国家自然科学基金(Nos.21425728,21177048,21173093,21477044,51472100),中央高校基本科研业务费专项资金(Nos.CCNU16A02029,CCNU16A04005),华中师范大学优秀博士学位论文培育计划(2015YBZD024&2016YBZZ031)资助.

Molecular Oxygen Activation with Nano Zero-valent Iron for Aerobic Degradation of Organic Contaminants and the Performance Enhancement

Mu Yi, Jia Falong, Ai Zhihui, Zhang Lizhi   

  1. Key Laboratory of Pesticide & Chemical Biology of Ministry of Education, Institute of Applied & Environmental Chemistry, Central China Normal University, Wuhan 430079
  • Received:2017-02-10 Published:2017-04-01
  • Contact: 10.6023/A17020047 E-mail:jennifer.ai@mail.ccnu.edu.cn;zhanglz@mail.ccnu.edu.cn
  • Supported by:

    Project supported by the National Key Research and Development Program of China (2016YFA0203000), National Natural Science Foundation of China (Nos. 21425728, 21177048, 21173093, 21477044, 51472100), Self-Determined Research Funds of CCNU from the Colleges' Basic Research and Operation of MOE (Nos. CCNU16A02029, CCNU16A04005), Excellent Doctorial Dissertation Cultivation Grant from Central China Normal University (2015YBZD024 and 2016YBZZ031).

Nano zero-valent iron (nZVI) is a special kind of iron with large specific surface area, strong reduction activity, and the environmental friendliness. nZVI was usually used to reductively degrade organic pollutants, but its long-term performance was poor and the organic pollutants could not be mineralized. Nano zero-valent iron can reductively activate molecular oxygen to generate reactive oxygen species for oxidation or even mineralization of organic pollutants. Recently, we found the core-shell structure dependent aerobic degradation of organic pollutants by nZVI and proposed a new physical insight into the molecular oxygen activation mechanism of the aerobic nZVI process, where the outward electrons transfer from the iron core initiate the two-electron molecular oxygen activation and surface bound ferrous ions on iron oxide shell favor the single-electron molecular oxygen activation. Several strategies have also been proposed to enhance the production of reactive oxidants by nZVI-induced oxygen activation. We confirmed that addition of extra ferrous ions into the nZVI/O2 system could generate more surface bound ferrous ions for significantly enhancing the generation of reactive oxygen species. Meanwhile, the introduction of some inorganic or organic ligands in the aerobic nZVI system could also improve the active oxygen species generation efficiency. Finally main typical environmental factors including of the pH value, coexisting ions, natural organic matter on the organic pollutants degradation with the aerobic nZVI were discussed. By the way, we also investigated the anoxic Cr(VI) removal with nZVI. It was found the Cr(VI) removal rate constant was mainly attributed to the reduction of Cr(VI) by the surface bound Fe(Ⅱ) besides the reduction of Cr(VI) adsorbed on the iron oxide shell via the electrons transferred from the iron core. We also demonstrated that the presence of oxygen molecule can inhibit Cr(VI) removal with nZVI, which was attributed to that the oxygen molecular activation could compete with Cr(VI) for the consumption of surface bond Fe(Ⅱ) and donor electrons transferred from Fe0 core.

Key words: nano zero-valent iron, molecular oxygen activation, reactive oxygen species, advanced oxidation technology