Th(IV) and U(VI) removal by TODGA in ionic liquids: extraction behavior and mechanism, and radiation effect

  • Zhen Dong
  • Wei-Jin Yuan
  • Chao Liu
  • Long Zhao
  • Chao Zhao
  • Fang-Dong Tang
  • Lin-Feng He


Extraction behavior of thorium(IV) and uranium(VI) from nitric acid (HNO3) was studied using N,N,N′,N′-tetraoctyldiglycolamide (TODGA) as extractant in different ionic liquids, and isooctane as comparison. Slope analyses with varying HNO3 concentrations and diluents revealed the extraction mechanism. With increasing length of alkyl chain and HNO3 concentration, the extraction mechanism of TODGA/IL system changed from cation exchange to neutral complex and/or anion exchange, and the molar ratio between TODGA and metal ions varied gradually from 2:1 to 1:1 for Th(IV) and 3:1 to 1:1 for U(VI). The kinetics and thermodynamic studies of Th(IV) and U(VI) by the best TODGA/[C2mim][NTf2] system showed that the extraction equilibrium was reached within 2 h and extraction reactions were endothermic. Compared to TODGA/isooctane system, TODGA/[C2mim][NTf2] system presented higher radiation stability under γ-irradiation. Therefore, it would have a promising application in spent fuel reprocessing.


Extraction TODGA Ionic liquids Thorium(IV) and uranium(VI) Radiation effect 


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Copyright information

© Shanghai Institute of Applied Physics, Chinese Academy of Sciences, Chinese Nuclear Society, Science Press China and Springer Science+Business Media Singapore 2017

Authors and Affiliations

  • Zhen Dong
    • 1
    • 2
  • Wei-Jin Yuan
    • 1
    • 2
  • Chao Liu
    • 1
  • Long Zhao
    • 1
    • 2
  • Chao Zhao
    • 3
  • Fang-Dong Tang
    • 3
  • Lin-Feng He
    • 3
  1. 1.Non-power Nuclear Technology Collaborative Innovation Center, School of Nuclear Technology and Chemistry & BiologyHubei University of Science and TechnologyXianningChina
  2. 2.School of Nuclear Science and EngineeringShanghai Jiao Tong UniversityShanghaiChina
  3. 3.Division of Chemistry and Ionizing Radiation Measurement TechnologyShanghai Institute of Measurement and Testing TechnologyShanghaiChina

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