能源化学(英文) ›› 2017, Vol. 26 ›› Issue (5): 1001-1006.DOI: 10.1016/j.jechem.2017.07.009

• ARTICLES • 上一篇    下一篇

CO2 absorption with ionic liquids at elevated temperatures

Lu Baia, Dawei Shanga, Mengdie Lia, Zhongde Daib, Liyuan Dengb, Xiangping Zhanga   

  1. a Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex System, Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
    b Department of Chemical Engineering, Norwegian University of Science and Technology(NTNU), Trondheim 7491, Norway
  • 收稿日期:2017-05-31 修回日期:2017-07-13 出版日期:2017-09-15 发布日期:2017-11-10
  • 通讯作者: Xiangping Zhang,E-mail address:xpzhang@ipe.ac.cn
  • 基金资助:

    This work was supported by the National Natural Science Foundation of China (21606233, 21436010), the National Natural Science Fund for Distinguished Young Scholars (21425625) and the Research Council of Norway through the CLIMIT program (215732).

CO2 absorption with ionic liquids at elevated temperatures

Lu Baia, Dawei Shanga, Mengdie Lia, Zhongde Daib, Liyuan Dengb, Xiangping Zhanga   

  1. a Key Laboratory of Green Process and Engineering, State Key Laboratory of Multiphase Complex System, Beijing Key Laboratory of Ionic Liquids Clean Process, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China;
    b Department of Chemical Engineering, Norwegian University of Science and Technology(NTNU), Trondheim 7491, Norway
  • Received:2017-05-31 Revised:2017-07-13 Online:2017-09-15 Published:2017-11-10
  • Contact: Xiangping Zhang,E-mail address:xpzhang@ipe.ac.cn
  • Supported by:

    This work was supported by the National Natural Science Foundation of China (21606233, 21436010), the National Natural Science Fund for Distinguished Young Scholars (21425625) and the Research Council of Norway through the CLIMIT program (215732).

摘要: CO2 capture with ionic liquids (ILs) has attracted many attentions, and most works focused on absorption ability at ambient temperatures, while seldom research was concerned at elevated temperatures. This not only limits the CO2 absorption application at elevated temperature, but also the determination of the operation condition of the CO2 desorption generally occurring at higher temperature. This work mainly reported CO2 solubilities in ILs at elevated temperatures and related properties were also provided. 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([CnMIm] [Tf2N]) ILs were selected as physical absorbents for CO2 capture in this work due to their relative higher CO2 absorption capacities and good thermal stabilities. The long-term stability tests showed that[CnMIm] [Tf2N] is thermally stable at 393.15 K for long time. CO2 solubilities in[CnMIm] [Tf2N] were systematically determined at temperatures from 353.15 K to 393.15 K. It demonstrated that CO2 solubility obviously increases with the increase of pressure while slightly decreases with increase of temperature. As the length of alkyl chain on the cation increases, CO2 solubility in ILs increases. Additionally, the thermodynamic properties including the Gibbs free energy, enthalpy, and entropy of CO2 were also calculated.

关键词: Ionic liquids, CO2 capture, Elevated temperature, Pre-combustion

Abstract: CO2 capture with ionic liquids (ILs) has attracted many attentions, and most works focused on absorption ability at ambient temperatures, while seldom research was concerned at elevated temperatures. This not only limits the CO2 absorption application at elevated temperature, but also the determination of the operation condition of the CO2 desorption generally occurring at higher temperature. This work mainly reported CO2 solubilities in ILs at elevated temperatures and related properties were also provided. 1-alkyl-3-methylimidazolium bis(trifluoromethylsulfonyl)imide ([CnMIm] [Tf2N]) ILs were selected as physical absorbents for CO2 capture in this work due to their relative higher CO2 absorption capacities and good thermal stabilities. The long-term stability tests showed that[CnMIm] [Tf2N] is thermally stable at 393.15 K for long time. CO2 solubilities in[CnMIm] [Tf2N] were systematically determined at temperatures from 353.15 K to 393.15 K. It demonstrated that CO2 solubility obviously increases with the increase of pressure while slightly decreases with increase of temperature. As the length of alkyl chain on the cation increases, CO2 solubility in ILs increases. Additionally, the thermodynamic properties including the Gibbs free energy, enthalpy, and entropy of CO2 were also calculated.

Key words: Ionic liquids, CO2 capture, Elevated temperature, Pre-combustion