Solubilities of the Gaseous and Liquid Solutes and Their Thermodynamics of Solubilization in the Novel Room-Temperature Ionic Liquids at Infinite Dilution by Gas Chromatography

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• 作者：Juan Zhang ; Qinghua Zhang ; Botao Qiao ; Youquan Deng
• 刊名：Journal of Chemical & Engineering Data
• 出版年：2007
• 出版时间：November 2007
• 年：2007
• 卷：52
• 期：6
• 页码：2277 - 2283
• 全文大小：84K
• 年卷期：v.52,no.6(November 2007)
• ISSN：1520-5134

文摘

The solubilities of C₂H₄ and CO₂ and the interactions of polar and nonpolar solutes with the novel ionic liquids(ILs) 1-butyronitrile-3-methylimidazolium bis(trifluoromethylsulfonyl) imidate (CpMIm[NTf₂]), 1-butyronitrile-2,3-dimethylimidazolium bis(trifluoromethylsulfonyl) imidate (CpMMIm[NTf₂]), 1-butyronitrile-3-methylimidazolium dicyanamide (CpMIm[N(CN)₂]), 1-butyronitrile-2,3-dimethylimidazolium dicyanamide (CpMMIm[N(CN)₂]), 1-butyl-3-methylimidazolium palmitate (BMIm[n-C₁₆H₃₃COO]), and 1-butyl-3-methylimidazoliumstearate (BMIm[n-C₁₈H₃₅COO]) were studied by gas chromatography at infinite dilution at T = (303.15, 313.15,323.15, and 333.15) K. Henry's law constant k_H of C₂H₄ and CO₂ gas, infinite dilution activity coefficient ,molar enthalpies of solution _solH, and partial molar excess enthalpies of solution H^E and of Gibbs energiesG^E were determined for polar and nonpolar solutes in these novel ILs. Compared with the 1,3-dialkylimidazoliumILs, cyano functional group substitution on the alkyl chain results in a remarkable decrease of the interactions ofhydrocarbons. BMIm[n-C₁₆H₃₁OO] and BMIm[n-C₁₈H₃₅OO] demonstrate strong solubilization for both polar andnonpolar solutes. Straight lines of ln V_g versus 1/T and ln versus 1/T were obtained for the majority of solutesin the temperature range. BMIm[NTf₂] and 1-octyl-3-methylimidazolium tetrafluoroborate (OMIm[BF₄]) showmuch better solubility for thiophene and are better solvents for the separations of thiophene from hydrocarbons.