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Jianji Wang - One of the best experts on this subject based on the ideXlab platform.
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Effect of Substituent Groups in Anions on Some Physicochemical Properties of 1-Butyl-3-Methylimidazolium Carboxylate Ionic Liquids
Journal of Chemical & Engineering Data, 2013Co-Authors: Yajuan Zhang, Jianji WangAbstract:In this work, four 1-Butyl-3-Methylimidazolium carboxylate ionic liquids (ILs) with different substituent groups in anions, including 1-Butyl-3-Methylimidazolium glycollate [C4mim][HOCH2COO], 1-Butyl-3-Methylimidazolium lactate [C4mim][CH3CHOHCOO], 1-Butyl-3-Methylimidazolium benzoate [C4mim][C6H5COO], and 1-Butyl-3-Methylimidazolium glycinate [C4mim][H2NCH2COO], have been synthesized and characterized. Their densities (ρ) and surface tensions (γ) have been determined experimentally in the temperature range of (298.15 to 343.15) K. By using thermodynamic and empirical equations, molar volume (Vm), isobaric expansivity (αp), standard entropy (S°), lattice energy (UPOT), surface excess entropy (Ss), vaporization enthalpy (ΔlgHm0) and Hildebrand solubility parameter (δH) of these ILs have been derived from density and surface tension data. The effects of substituent groups in carboxylate anions on densities and surface tensions of these ILs have been assessed from the analysis of the structure–property relat...
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Viscosities and Conductivities of 1-Butyl-3-Methylimidazolium Carboxylates Ionic Liquids at Different Temperatures
Journal of Chemical & Engineering Data, 2012Co-Authors: Yajuan Zhang, Jianji WangAbstract:In recent years, 1-Butyl-3-Methylimidazolium carboxylates ionic liquids (ILs) have been reported to be powerful solvents for the dissolution of cellulose and chitosan. However, very few studies have been conducted to investigate their basic physicochemical properties such as viscosity and conductivity. In this work, we have synthesized 1-Butyl-3-Methylimidazolium carboxylates ILs: 1-Butyl-3-Methylimidazolium formate ([C4mim][HCOO]), 1-Butyl-3-Methylimidazolium acetate ([C4mim][CH3COO]), 1-Butyl-3-Methylimidazolium propionate ([C4mim][CH3CH2COO]), and 1-Butyl-3-Methylimidazolium butyrate ([C4mim][CH3(CH2)2COO]), in which the alkyl chain length in the anions is varied. The experimental viscosities (η) and conductivities (σ) for these ILs have been determined at different temperatures, and well correlated by the Vogel–Fulcher–Tammann (VFT) equation. Walden plots indicate an increase in ion pairs and/or ionic aggregates in the ILs with increasing alkyl chain length. Furthermore, the effect of alkyl chain leng...
João A. P. Coutinho - One of the best experts on this subject based on the ideXlab platform.
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Density and Viscosity Data for Binary Mixtures of 1-Alkyl-3-methylimidazolium Alkylsulfates + Water
Journal of Chemical & Engineering Data, 2012Co-Authors: Arijit Bhattacharjee, Catarina Varanda, Mara G. Freire, Silvana Matted, Luís M. N. B. F. Santos, Isabel M. Marrucho, João A. P. CoutinhoAbstract:Density and viscosity experimental data for binary mixtures of 1-alkyl-3-methylimidazolium alkylsulfates + water are reported using four ionic liquids: 1-Butyl-3-Methylimidazolium hydrogensulfate [C4mim][HSO4], 1-Butyl-3-Methylimidazolium methylsulfate [C4mim][C1SO4], 1-ethyl-3-methylimidazolium methylsulfate [C2mim][C1SO4], and 1-ethyl-3-methylimidazolium ethylsulfate [C2mim][C2SO4]. The choice of the ionic liquids allows us to compare the effects of incrementing the alkyl chain length in the cation and the anion on the measured thermophysical properties behavior. The Gardas and Coutinho group contribution methods were applied to the description of the pure component densities and viscosities allowing the estimation of new group contribution parameters, to extend the applicability of these methods to new ILs. Excess molar volumes and viscosity deviations were calculated and correlated by Redlich–Kister polynomial expansions.
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on the spontaneous carboxylation of 1 butyl 3 methylimidazolium acetate by carbon dioxide
Chemical Communications, 2012Co-Authors: M Besnard, João A. P. Coutinho, Isabel M Cabaco, Fabian Vaca Chavez, Noel Pinaud, P J Sebastiao, Y DantenAbstract:The formation of 1-Butyl-3-Methylimidazolium-2-carboxylate in the mixture of CO2 with 1-Butyl-3-Methylimidazolium acetate under mild conditions (298 K, 0.1 MPa) has been put in evidence in the liquid phase using Raman and infrared spectroscopy complemented by DFT calculations and NMR (1H, 13C, 15N) spectroscopy.
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High pressure phase behavior of carbon dioxide in 1-Butyl-3-Methylimidazolium bis(trifluoromethylsulfonyl)imide and 1-Butyl-3-Methylimidazolium dicyanamide ionic liquids
The Journal of Supercritical Fluids, 2009Co-Authors: Pedro J. Carvalho, Isabel M. Marrucho, Víctor H. Álvarez, Martín Aznar, João A. P. CoutinhoAbstract:Abstract The acidity/basicity of the reaction media has a substantial influence on the efficiency of many reactive processes; therefore, a new class of acidic or basic ionic liquids is gaining special attention due to the possibility of increasing the efficiency of many processes by a wise manipulation of their properties. The absorption of sour gases is one of the processes that can be enhanced by the basic character of the ionic liquid. The fluorination of the cation or anion can also contribute to the gas solubility enhancement. In this work, these two characteristics are evaluated and compared through the study of gas–liquid equilibrium of two ionic liquids, 1-Butyl-3-Methylimidazolium dicyanamide ([C4mim][DCA]) and 1-Butyl-3-Methylimidazolium bis(trifluoromethylsulfonyl)imide ([C4mim][Tf2N]), with carbon dioxide (CO2) at temperatures up to 363 K and pressures up to 74 MPa. A thermodynamic model based on the Peng–Robinson equation of state with the Wong–Sandler mixing rule, using the UNIQUAC model for the activity coefficients, was used to describe the experimental data and for the estimation of the Henry's constants. The solubility of CO2 in 1-Butyl-3-Methylimidazolium dicyanamide is much lower than anticipated on the basis of the reported pKa of the anion when compared with the acetate anion. No chemisorption is observed and the solvation enthalpy is quite low, ruling out any Lewis acid/base interaction between the anion and the CO2. The 1-Butyl-3-Methylimidazolium bis(trifluoromethylsulfonyl)imide ionic liquid, known to present one of the highest solubilities towards CO2 due to the presence of fluoroalkyl groups, showed a much larger solubility for CO2 than 1-Butyl-3-Methylimidazolium dicyanamide.
Huen Lee - One of the best experts on this subject based on the ideXlab platform.
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refractive index and heat capacity of 1 butyl 3 methylimidazolium bromide and 1 butyl 3 methylimidazolium tetrafluoroborate and vapor pressure of binary systems for 1 butyl 3 methylimidazolium bromide trifluoroethanol and 1 butyl 3 methylimidazolium
Fluid Phase Equilibria, 2004Co-Authors: Ki-sub Kim, Bae-kun Shin, Huen Lee, F ZieglerAbstract:Abstract 1-Butyl-3-Methylimidazolium tetrafluoroborate ([BMIm][BF 4 ]) + 2,2,2-trifluoroethanol (TFE) and 1-Butyl-3-Methylimidazolium bromide ([BMIm][Br]) + TFE mixtures exhibit properties which render them suitable as candidates for working fluids in absorption heat pumps or chillers. Refractive indices and heat capacities of each pure ionic liquid were investigated in the temperature range of 298.2–323.2 K. Vapor pressures were measured by using the boiling point method in the concentration range of 40.0–90.0 mass% of ionic liquid and were correlated with an Antoine-type equation. The average absolute deviations between experimental and calculated values were 0.6% for the [BMIm][BF 4 ] + TFE and 0.4% for the [BMIm][Br] + TFE system, respectively.
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Physical and Electrochemical Properties of 1-Butyl-3-Methylimidazolium Bromide, 1-Butyl-3-Methylimidazolium Iodide, and 1-Butyl-3-Methylimidazolium Tetrafluoroborate
Korean Journal of Chemical Engineering, 2004Co-Authors: Ki-sub Kim, Bae-kun Shin, Huen LeeAbstract:The density, viscosity, refractive index, heat capacity, heat of dilution, ionic conductivity, and electrochemical stability of 1-Butyl-3-Methylimidazolium bromide ([bmim][Br]), 1-Butyl-3-Methylimidazolium iodide ([bmim][I]), and 1-Butyl-3-Methylimidazolium tetrafluoroborate ([bmim][BF4]) were measured at room temperature or over a temperature range of 293.2 to 323.2 K. The density and refractive index values of [bmim][I] appeared to be the highest among three ionic liquids (ILs). However, the experimental viscosity values of [bmim][Br] were higher than those of [bmim][BF4], while the heat capacities and heats of dilution of [bmim][BF4] were higher than those of [bmim][Br]. The cyclic voltammogram of [bmim][br] and [bmim][BF4] indicated electrochemical windows in the stability range from 2.7 V of [bmim][[Br] to 4.7 V of [bmim][BF4].
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Vapor pressures of the 1-Butyl-3-Methylimidazolium bromide + water, 1-Butyl-3-Methylimidazolium tetrafluoroborate + water, and 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate + water systems
Journal of Chemical & Engineering Data, 2004Co-Authors: Ki-sub Kim, Sukjeong Choi, Seung-yeob Park, Huen LeeAbstract:This work presents the vapor pressures of the following binary imidazolium-based ionic liquid (IL) + water solutions: 1-Butyl-3-Methylimidazolium bromide ([bmim][Br]) + water, 1-Butyl-3-Methylimidazolium tetrafluoroborate ([bmim][BF4]) + water, and 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([hydemim][BF4]) + water. Vapor pressures were measured by using the boiling-point method in the temperature range of (304.8 to 475.2) K and in the concentration range of (20.0 to 80.0) mol % of ILs and were correlated with an Antoine-type equation. The resulting average absolute deviations (AAD) between the experimental and calculated values were found to be (0.419, 1.16, and 0.682) % for the [bmim][Br] + water, [bmim][BF4] + water, and [hydemim][BF4] + water solutions, respectively.
Ki-sub Kim - One of the best experts on this subject based on the ideXlab platform.
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refractive index and heat capacity of 1 butyl 3 methylimidazolium bromide and 1 butyl 3 methylimidazolium tetrafluoroborate and vapor pressure of binary systems for 1 butyl 3 methylimidazolium bromide trifluoroethanol and 1 butyl 3 methylimidazolium
Fluid Phase Equilibria, 2004Co-Authors: Ki-sub Kim, Bae-kun Shin, Huen Lee, F ZieglerAbstract:Abstract 1-Butyl-3-Methylimidazolium tetrafluoroborate ([BMIm][BF 4 ]) + 2,2,2-trifluoroethanol (TFE) and 1-Butyl-3-Methylimidazolium bromide ([BMIm][Br]) + TFE mixtures exhibit properties which render them suitable as candidates for working fluids in absorption heat pumps or chillers. Refractive indices and heat capacities of each pure ionic liquid were investigated in the temperature range of 298.2–323.2 K. Vapor pressures were measured by using the boiling point method in the concentration range of 40.0–90.0 mass% of ionic liquid and were correlated with an Antoine-type equation. The average absolute deviations between experimental and calculated values were 0.6% for the [BMIm][BF 4 ] + TFE and 0.4% for the [BMIm][Br] + TFE system, respectively.
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Physical and Electrochemical Properties of 1-Butyl-3-Methylimidazolium Bromide, 1-Butyl-3-Methylimidazolium Iodide, and 1-Butyl-3-Methylimidazolium Tetrafluoroborate
Korean Journal of Chemical Engineering, 2004Co-Authors: Ki-sub Kim, Bae-kun Shin, Huen LeeAbstract:The density, viscosity, refractive index, heat capacity, heat of dilution, ionic conductivity, and electrochemical stability of 1-Butyl-3-Methylimidazolium bromide ([bmim][Br]), 1-Butyl-3-Methylimidazolium iodide ([bmim][I]), and 1-Butyl-3-Methylimidazolium tetrafluoroborate ([bmim][BF4]) were measured at room temperature or over a temperature range of 293.2 to 323.2 K. The density and refractive index values of [bmim][I] appeared to be the highest among three ionic liquids (ILs). However, the experimental viscosity values of [bmim][Br] were higher than those of [bmim][BF4], while the heat capacities and heats of dilution of [bmim][BF4] were higher than those of [bmim][Br]. The cyclic voltammogram of [bmim][br] and [bmim][BF4] indicated electrochemical windows in the stability range from 2.7 V of [bmim][[Br] to 4.7 V of [bmim][BF4].
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Vapor pressures of the 1-Butyl-3-Methylimidazolium bromide + water, 1-Butyl-3-Methylimidazolium tetrafluoroborate + water, and 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate + water systems
Journal of Chemical & Engineering Data, 2004Co-Authors: Ki-sub Kim, Sukjeong Choi, Seung-yeob Park, Huen LeeAbstract:This work presents the vapor pressures of the following binary imidazolium-based ionic liquid (IL) + water solutions: 1-Butyl-3-Methylimidazolium bromide ([bmim][Br]) + water, 1-Butyl-3-Methylimidazolium tetrafluoroborate ([bmim][BF4]) + water, and 1-(2-hydroxyethyl)-3-methylimidazolium tetrafluoroborate ([hydemim][BF4]) + water. Vapor pressures were measured by using the boiling-point method in the temperature range of (304.8 to 475.2) K and in the concentration range of (20.0 to 80.0) mol % of ILs and were correlated with an Antoine-type equation. The resulting average absolute deviations (AAD) between the experimental and calculated values were found to be (0.419, 1.16, and 0.682) % for the [bmim][Br] + water, [bmim][BF4] + water, and [hydemim][BF4] + water solutions, respectively.
Yajuan Zhang - One of the best experts on this subject based on the ideXlab platform.
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Effect of Substituent Groups in Anions on Some Physicochemical Properties of 1-Butyl-3-Methylimidazolium Carboxylate Ionic Liquids
Journal of Chemical & Engineering Data, 2013Co-Authors: Yajuan Zhang, Jianji WangAbstract:In this work, four 1-Butyl-3-Methylimidazolium carboxylate ionic liquids (ILs) with different substituent groups in anions, including 1-Butyl-3-Methylimidazolium glycollate [C4mim][HOCH2COO], 1-Butyl-3-Methylimidazolium lactate [C4mim][CH3CHOHCOO], 1-Butyl-3-Methylimidazolium benzoate [C4mim][C6H5COO], and 1-Butyl-3-Methylimidazolium glycinate [C4mim][H2NCH2COO], have been synthesized and characterized. Their densities (ρ) and surface tensions (γ) have been determined experimentally in the temperature range of (298.15 to 343.15) K. By using thermodynamic and empirical equations, molar volume (Vm), isobaric expansivity (αp), standard entropy (S°), lattice energy (UPOT), surface excess entropy (Ss), vaporization enthalpy (ΔlgHm0) and Hildebrand solubility parameter (δH) of these ILs have been derived from density and surface tension data. The effects of substituent groups in carboxylate anions on densities and surface tensions of these ILs have been assessed from the analysis of the structure–property relat...
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Viscosities and Conductivities of 1-Butyl-3-Methylimidazolium Carboxylates Ionic Liquids at Different Temperatures
Journal of Chemical & Engineering Data, 2012Co-Authors: Yajuan Zhang, Jianji WangAbstract:In recent years, 1-Butyl-3-Methylimidazolium carboxylates ionic liquids (ILs) have been reported to be powerful solvents for the dissolution of cellulose and chitosan. However, very few studies have been conducted to investigate their basic physicochemical properties such as viscosity and conductivity. In this work, we have synthesized 1-Butyl-3-Methylimidazolium carboxylates ILs: 1-Butyl-3-Methylimidazolium formate ([C4mim][HCOO]), 1-Butyl-3-Methylimidazolium acetate ([C4mim][CH3COO]), 1-Butyl-3-Methylimidazolium propionate ([C4mim][CH3CH2COO]), and 1-Butyl-3-Methylimidazolium butyrate ([C4mim][CH3(CH2)2COO]), in which the alkyl chain length in the anions is varied. The experimental viscosities (η) and conductivities (σ) for these ILs have been determined at different temperatures, and well correlated by the Vogel–Fulcher–Tammann (VFT) equation. Walden plots indicate an increase in ion pairs and/or ionic aggregates in the ILs with increasing alkyl chain length. Furthermore, the effect of alkyl chain leng...
