CO2 Capture and Separation Properties in the Ionic Liquid 1-n-Butyl-3-Methylimidazolium Nonafluorobutylsulfonate

Materials

Lingyun Zhou¹  Jing Fan¹ 

[1] School of Environment, Henan Normal University, Xinxiang 453007, Henan, China; E-Mails:

关键词: carbon capture;    selectivity;    ionic liquid;    Krichevsky-Kasarnovsky equation;    1-n-Butyl-3-methylimidazolium nonafluorobutylsulfonate;   

DOI  :  10.3390/ma7053867

来源: mdpi

【 摘 要 】

Recently, the use of ionic liquids (ILs) for carbon capture and separation processes has gained great interest by many researchers due to the high solubility of CO₂ in ILs. In the present work, solubility measurements of CO₂ in the novel IL 1-n-butyl-3-methylimidazolium nonafluorobutylsulfonate [C₄mim][CF₃CF₂CF₂CF₂SO₃] were performed with a high-pressure view-cell technique in the temperature range from 293.15 to 343.15 K and pressures up to about 4.2 MPa. For comparison, solubilities of H₂, N₂, and O₂ in the IL were also measured at 323.15 K via the same procedure. The Krichevsky-Kasarnovsky equation was employed to correlate the measured solubility data. Henry’s law constants, enthalpies, and entropies of absorption for CO₂ in the IL were also determined and presented. The CO₂ solubility in this IL was compared with other ILs sharing the same cation. It was shown that the solubility of CO₂ in these ILs follows the sequence: [C₄mim][CF₃CF₂CF₂CF₂SO₃] ≈ [C₄mim][Tf₂N] > [C₄mim][CF₃CF₂CF₂COO] > [C₄mim][BF₄], and the solubility selectivity of CO₂ relative to O₂, N₂, and H₂ in [C₄mim][CF₃CF₂CF₂CF₂SO₃] was 8, 16, and 22, respectively. Furthermore, this IL is regenerable and exhibits good stability. Therefore, the IL reported here would be a promising sorbent for CO₂.

【 授权许可】

CC BY   
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