化学学报 ›› 2021, Vol. 79 ›› Issue (12): 1415-1424.DOI: 10.6023/A21080380 上一篇    下一篇

综述

镎和钚与环境中无机阴离子的配位化学研究进展

董雪a, 曹鸿a, 徐雷a,b, 王志鹏a,*(), 陈靖a, 徐超a,*()   

  1. a 清华大学 核能与新能源技术研究院 北京 100084
    b 浙江大学 原子核农业科学研究所 杭州 310058
  • 投稿日期:2021-08-13 发布日期:2021-10-08
  • 通讯作者: 王志鹏, 徐超
  • 作者简介:

    董雪, 男, 博士研究生. 2018年7月毕业于西南科技大学国防科技学院, 获学士学位. 目前就读于清华大学核能与新能源技术研究院, 主要从事核废物处理中超铀元素的化学行为和分离机制研究.

    王志鹏, 男, 助理研究员. 2019年于四川大学获放射化学专业博士学位. 2019~2021年在清华大学核能与新能源技术研究院开展博士后研究. 2021年8月起任职助理研究员. 主要从事于核燃料循环相关的分离化学、氧化还原化学和配位化学研究.

    徐超, 男, 清华大学核能与新能源技术研究院长聘副教授. 2009年于北京大学获理学博士学位, 同年进入清华大学核能与新能源技术研究院工作至今. 中国化学会核化学与放射化学分会理事会副秘书长, 中国核学会锕系物理与化学分会理事. 主要研究领域包括放射性废物高效分离和处理技术, 锕系及镧系离子配位化学等.

  • 基金资助:
    国家自然科学基金(21822606); 国家自然科学基金(21790372)

Advances in Environmental Coordination Chemistry of Np and Pu with Inorganic Anions in Aqueous Solution

Xue Donga, Hong Caoa, Lei Xua,b, Zhipeng Wanga(), Jing Chena, Chao Xua()   

  1. a Institute of Nuclear and New Energy Technology, Tsinghua University, Beijing 100084
    b Institute of Nuclear-Agricultural Sciences, Zhejiang University, Hangzhou 310058
  • Received:2021-08-13 Published:2021-10-08
  • Contact: Zhipeng Wang, Chao Xu
  • Supported by:
    National Natural Science Foundation of China(21822606); National Natural Science Foundation of China(21790372)

镎(Np)和钚(Pu)是核能领域两种重要的锕系元素, 其在水溶液中的配位化学对于了解和控制其在水环境中的种态分布和迁移行为具有重要意义. Review了近十几年来国内外Np和Pu与环境中常见无机阴离子在水溶液中的配位化学研究进展, 重点阐述了不同价态Np/Pu离子与OH$CO_3^{2-}$$SO_4^{2-}$、Cl$NO_3^-$、F$PO_4^{3-}$等阴离子之间形成的配位物种和配位热力学信息, 并对该领域存在的关键科学问题和未来发展方向进行了分析和展望.

关键词: 镎, 钚, 环境, 无机阴离子, 配位化学, 热力学

Neptunium (Np) and plutonium (Pu) are two important actinides in nuclear industry. They can be generated through neutron capture of uranium (U) in reactors or decay from other transuranic elements. Representative isotopes of Np and Pu such as 237Np and 239Pu have long half-lives and possess high radiotoxicity, therefore may impose great hazard to biological system if they are released into the environment. The rich redox chemistry of Np and Pu further adds complexity of their chemical behavior in the environment. The coordination chemistry of Np and Pu in aqueous solution is of great significance to help understand and control their speciation distribution and migration behaviors in aqua environment. This article reviews the advances in coordination chemistry of Np and Pu with several common inorganic anions (OH, $CO_3^{2-}$, $SO_4^{2-}$, Cl, $NO_3^-$, F, $PO_4^{3-}$) in aqueous solution, especially the speciation and coordination thermodynamics between Np/Pu in different oxidation states and these anions. In general, Np and Pu ions in the same oxidation state exhibit similar coordination behavior (species, structure, stability constants, etc.) when coordinating with the same anion. The coordination strength for Np/Pu ions in different oxidation states with the same anion ligand is roughly in the order of IV>III, VI>V. For the coordination of Np/Pu ions with different anions, the strength sequences are OH>F> ${H_2}PO_4^-$> $NO_3^-$>Cl for monovalent anions and $CO_3^{2-}$> $HPO_4^{2-}$> $SO_4^{2-}$ for divalent anions. Factors such as instability of Np/Pu ions in some oxidation states, weak complexation, and low solubility of the complexes in the aqueous solution cause difficulties in obtaining precise and reliable coordination parameters for these ions experimentally. Moreover, the coordination parameters determined by different methods may vary with each other. To obtain more reliable parameters for the coordination of Np/Pu ions with these anions in the future, the use of more advanced characterization methods and the assistance of theoretical computation may provide strong support.

Key words: neptunium, plutonium, environment, inorganic anion, coordination chemistry, thermodynamics