An ionic liquid (IL) based on lactate,1-butyl-3-methylimidazolium lactate ([C4mim][Lact]),has been prepared and characterized by 1H nuclear magnetic resonance (NMR) spectroscopy and differential scanning calorimetry (...An ionic liquid (IL) based on lactate,1-butyl-3-methylimidazolium lactate ([C4mim][Lact]),has been prepared and characterized by 1H nuclear magnetic resonance (NMR) spectroscopy and differential scanning calorimetry (DSC).Since the IL can form strong hydrogen bonds with water,trace water is a problematic impurity in the IL.Using the standard addition method (SAM),the density,refractive index and surface tension of [C4mim][Lact] were measured in the temperature range (308.15 to 343.15 ± 0.05) K.On the basis of the experimental data,the parachor and molar volume for [C4mim][Lact],and the molecular volume V m,surface tension γ,molar enthalpy of vaporization △lgHm 0,refractive index n D,and the thermal expansion coefficients,for the homologues [Cnmim][Lact] (n=2,3,4,5,and 6) were estimated using semi-empirical methods.The estimated values are in good agreement with the experimental data.展开更多
The amino acid ionic liquids （AAILs） [C3mim][Gly] （1-propyl-3-methylimidazolium glycine） and [C4mim][Gly] （l-butyl-3- methylimidazolium glycine） have been prepared by the neutralization method and characterized ...The amino acid ionic liquids （AAILs） [C3mim][Gly] （1-propyl-3-methylimidazolium glycine） and [C4mim][Gly] （l-butyl-3- methylimidazolium glycine） have been prepared by the neutralization method and characterized by IH NMR spectroscopy and differential scanning calorimetry （DSC）. The values of their density, surface tension and refractive index were measured at （298.15 ± 0.05） K. Since the AAILs can form strong hydrogen bonds with water, small amounts of water are difficult to remove from the AAILs by common methods. In order to eliminate the effect of the impurity water, the standard addition method （SAM） was applied to these measurements. A new concept which is called the ionic parachor has been put forward. The [Cn mim]＋ cations were treated as a group of reference ions and the individual values of their ionic parachor were evaluated in terms of an extrathermodynamic assumption. Then, using the values of the ionic parachor of reference ions, the parachor, surface tension y and refractive index no of the ionic liquids investigated in this work were estimated. The estimated values correlate quite well with the corresponding experimental values.展开更多
基金supported by the Research Fund of the Education Bureau of Liaoning Province(2009S041,2008S103)the National Natural Science Foundation of China(21003068,20773056,21071073)the Research Fund of Liaoning University
文摘An ionic liquid (IL) based on lactate,1-butyl-3-methylimidazolium lactate ([C4mim][Lact]),has been prepared and characterized by 1H nuclear magnetic resonance (NMR) spectroscopy and differential scanning calorimetry (DSC).Since the IL can form strong hydrogen bonds with water,trace water is a problematic impurity in the IL.Using the standard addition method (SAM),the density,refractive index and surface tension of [C4mim][Lact] were measured in the temperature range (308.15 to 343.15 ± 0.05) K.On the basis of the experimental data,the parachor and molar volume for [C4mim][Lact],and the molecular volume V m,surface tension γ,molar enthalpy of vaporization △lgHm 0,refractive index n D,and the thermal expansion coefficients,for the homologues [Cnmim][Lact] (n=2,3,4,5,and 6) were estimated using semi-empirical methods.The estimated values are in good agreement with the experimental data.
基金supported by the National Natural Science Foundation ofChina (20903053)the Education Bureau of Liaoning Province(LS2010069)Liaoning University Research Funding
文摘The amino acid ionic liquids （AAILs） [C3mim][Gly] （1-propyl-3-methylimidazolium glycine） and [C4mim][Gly] （l-butyl-3- methylimidazolium glycine） have been prepared by the neutralization method and characterized by IH NMR spectroscopy and differential scanning calorimetry （DSC）. The values of their density, surface tension and refractive index were measured at （298.15 ± 0.05） K. Since the AAILs can form strong hydrogen bonds with water, small amounts of water are difficult to remove from the AAILs by common methods. In order to eliminate the effect of the impurity water, the standard addition method （SAM） was applied to these measurements. A new concept which is called the ionic parachor has been put forward. The [Cn mim]＋ cations were treated as a group of reference ions and the individual values of their ionic parachor were evaluated in terms of an extrathermodynamic assumption. Then, using the values of the ionic parachor of reference ions, the parachor, surface tension y and refractive index no of the ionic liquids investigated in this work were estimated. The estimated values correlate quite well with the corresponding experimental values.
