SCI和EI收录∣中国化工学会会刊

›› 2017, Vol. 25 ›› Issue (1): 26-31.DOI: 10.1016/j.cjche.2016.05.005

• Separation Science and Engineering • 上一篇    下一篇

Orthogonal array design for the optimization of stripping Sr(II) from ionic liquids using supercritical CO2

Tao Yang, Jing Fu, Qingde Chen, Xinghai Shen   

  1. Beijing National Laboratory for Molecular Sciences(BNLMS), Fundamental Science on Radiochemistry and Radiation Chemistry Laboratory, College of Chemistry and Molecular Engineering,;Peking University, Beijing 100871, China
  • 收稿日期:2016-03-20 修回日期:2016-05-09 出版日期:2017-01-28 发布日期:2017-02-15
  • 通讯作者: Xinghai Shen,Tel.:+861062765915;Fax:+861062759191.E-mail address:xshen@pku.edu.cn
  • 基金资助:
    Supported by the National Natural Science Foundation of China (91226112).

Orthogonal array design for the optimization of stripping Sr(II) from ionic liquids using supercritical CO2

Tao Yang, Jing Fu, Qingde Chen, Xinghai Shen   

  1. Beijing National Laboratory for Molecular Sciences(BNLMS), Fundamental Science on Radiochemistry and Radiation Chemistry Laboratory, College of Chemistry and Molecular Engineering,;Peking University, Beijing 100871, China
  • Received:2016-03-20 Revised:2016-05-09 Online:2017-01-28 Published:2017-02-15
  • Supported by:
    Supported by the National Natural Science Foundation of China (91226112).

摘要: The strontium ions extracted from the aqueous phase into 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (C2mimNTf2) with dicyclohexyl-18-crown-6 (DCH18C6) was stripped effectively by supercritical CO2 (sc-CO2). Hexafluoroacetylacetone (HFAA)-acetonitrile was found to be an excellent modifier of sc-CO2 to enhance the stripping efficiency. In the orthogonal array design (OAD), OA25 (55) matrix was employed to optimize the stripping of Sr(II) from the DCH18C6-C2mimNTf2 system. Effects of five experimental factors:temperature, pressure, concentration of HFAA, static and dynamic extraction times as well as each factor at five-levels on the stripping of Sr(II) were optimized. The effects of these parameters were treated by the analysis of variance (ANOVA). The results showed that Sr(II) could be nearly 100% extracted from the IL phase at 308 K, 30 MPa, 40 min of dynamic extraction and 60 mmol·L-1 HFAA in acetonitrile, respectively. Finally, the stripping mechanism was studied by ESI-MS.

关键词: Supercritical CO2 stripping, Ionic liquid, Strontium, Orthogonal array design

Abstract: The strontium ions extracted from the aqueous phase into 1-ethyl-3-methylimidazolium bis(trifluoromethylsulfonyl) imide (C2mimNTf2) with dicyclohexyl-18-crown-6 (DCH18C6) was stripped effectively by supercritical CO2 (sc-CO2). Hexafluoroacetylacetone (HFAA)-acetonitrile was found to be an excellent modifier of sc-CO2 to enhance the stripping efficiency. In the orthogonal array design (OAD), OA25 (55) matrix was employed to optimize the stripping of Sr(II) from the DCH18C6-C2mimNTf2 system. Effects of five experimental factors:temperature, pressure, concentration of HFAA, static and dynamic extraction times as well as each factor at five-levels on the stripping of Sr(II) were optimized. The effects of these parameters were treated by the analysis of variance (ANOVA). The results showed that Sr(II) could be nearly 100% extracted from the IL phase at 308 K, 30 MPa, 40 min of dynamic extraction and 60 mmol·L-1 HFAA in acetonitrile, respectively. Finally, the stripping mechanism was studied by ESI-MS.

Key words: Supercritical CO2 stripping, Ionic liquid, Strontium, Orthogonal array design