SCI和EI收录∣中国化工学会会刊

中国化学工程学报 ›› 2019, Vol. 27 ›› Issue (8): 1828-1836.DOI: 10.1016/j.cjche.2019.01.009

• Separation Science and Engineering • 上一篇    下一篇

Grouping separation of mixed rare earths from their coexisting aqueous solutions by liquid-column elution

Wenjuan Cao1,2, Kun Huang3, Xiaoqin Wang1,2, Huizhou Liu1   

  1. 1 CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
  • 收稿日期:2018-11-20 修回日期:2018-12-22 出版日期:2019-08-28 发布日期:2019-11-16
  • 通讯作者: Kun Huang
  • 基金资助:
    Supported by the National Natural Science Foundation of China (51574213, 51074150), and the Key Project of Chinese National Programs for Fundamental Research and Development (2012CBA01203).

Grouping separation of mixed rare earths from their coexisting aqueous solutions by liquid-column elution

Wenjuan Cao1,2, Kun Huang3, Xiaoqin Wang1,2, Huizhou Liu1   

  1. 1 CAS Key Laboratory of Green Process and Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
    2 University of Chinese Academy of Sciences, Beijing 100049, China;
    3 School of Metallurgical and Ecological Engineering, University of Science and Technology Beijing, Beijing 100083, China
  • Received:2018-11-20 Revised:2018-12-22 Online:2019-08-28 Published:2019-11-16
  • Contact: Kun Huang
  • Supported by:
    Supported by the National Natural Science Foundation of China (51574213, 51074150), and the Key Project of Chinese National Programs for Fundamental Research and Development (2012CBA01203).

摘要: A new approach was proposed for grouping separation of 14 lanthanide rare-earth ions from their coexisting mixed aqueous solutions, by performing liquid-column elution using the aqueous solution containing 14 lanthanide rare-earth ions as the stationary phase and the dispersed organic oil droplets containing P507 extractant as the mobile phase. It was revealed that 14 lanthanide rare-earth ions could be separated into four groups, according to the lanthanide tetrad effect, respectively eluting out from the liquid column at different time in a certain order. Various effects including the saponification degree of P507, the concentration of P507 in organic phase, the length and inner diameter of the extraction column on the performance of grouping separation of rare-earth ions were discussed. The changes of the mass transfer coefficients were also investigated. The separation efficiency of the four groups of rareearth elements (REEs) was evaluated based on the elution resolution, Rs, of the elution peaks of La(III), Gd(III), Ho(III) and Lu(III), the four representative elements respectively from each of the four groups of REEs. Experimental results demonstrated that the separation of REEs by liquid-column elution mainly depended on the competitive adsorption of different rare-earth groups onto the surface of ascending P507 oil droplets. The affinity of different rare-earth groups with P507 extractant and a limited adsorption capacity of P507 molecules at the surface of the oil droplets ascending in liquid column play the important role. The present work highlights a promising technique for grouping separation of multiple lanthanide elements co-existing complex systems.

关键词: Elution, Lanthanide tetrad effect, Rare-earths, Group separation

Abstract: A new approach was proposed for grouping separation of 14 lanthanide rare-earth ions from their coexisting mixed aqueous solutions, by performing liquid-column elution using the aqueous solution containing 14 lanthanide rare-earth ions as the stationary phase and the dispersed organic oil droplets containing P507 extractant as the mobile phase. It was revealed that 14 lanthanide rare-earth ions could be separated into four groups, according to the lanthanide tetrad effect, respectively eluting out from the liquid column at different time in a certain order. Various effects including the saponification degree of P507, the concentration of P507 in organic phase, the length and inner diameter of the extraction column on the performance of grouping separation of rare-earth ions were discussed. The changes of the mass transfer coefficients were also investigated. The separation efficiency of the four groups of rareearth elements (REEs) was evaluated based on the elution resolution, Rs, of the elution peaks of La(III), Gd(III), Ho(III) and Lu(III), the four representative elements respectively from each of the four groups of REEs. Experimental results demonstrated that the separation of REEs by liquid-column elution mainly depended on the competitive adsorption of different rare-earth groups onto the surface of ascending P507 oil droplets. The affinity of different rare-earth groups with P507 extractant and a limited adsorption capacity of P507 molecules at the surface of the oil droplets ascending in liquid column play the important role. The present work highlights a promising technique for grouping separation of multiple lanthanide elements co-existing complex systems.

Key words: Elution, Lanthanide tetrad effect, Rare-earths, Group separation