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Author: search.filters.author.Deenadayalu, NirmalaSubject: search.filters.subject.Ionic liquid

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    Densities and excess molar volume for the ternary systems (1-Butyl-3-methylimidazolium methyl sulphate + Nitromethane + Methanol or Ethanol or 1-Propanol) at T = (303.15 and 313.15) K
    (SA Epublications, 2013) Bahadur, Indra; Deenadayalu, Nirmala
    The densities of the ternary systems containing the ionic liquid 1-butyl-3-methylimidazolium methyl sulphate ([BMIM]+[MeSO4]–) were determined. The ternary systems studied were ([BMIM]+[MeSO4]– + nitromethane + methanol or ethanol or 1-propanol) at the temperatures (303.15 and 313.15) K. The ternary excess molar volumes were calculated from the experimental densities at each temperature, being negative for all mole fractions of the ionic liquid. The minimum ternary excess molar volumes increase with an increase in temperature for the systems ([BMIM]+[MeSO4]– + nitromethane + methanol or ethanol), and decrease for the system ([BMIM]+ [MeSO4]–+ nitromethane + 1-propanol). The results are interpreted in terms of the alcohol chain length and the intermolecular interactions.
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    Apparent molar volume and apparent molar isentropic compressibility for the binary systems {methyltrioctylammoniumbis(trifluoromethylsulfonyl)imide + ethyl acetate or ethanol} at different temperatures under atmospheric pressure
    (Elsevier, 2013-05-20) Bahadur, Indra; Deenadayalu, Nirmala
    The density (d) and speed of sound (u) for the binary systems were measured at 298.15, 303.15, 308.15, and 313.15 K under atmospheric pressure. The binary systems contained the ionic liquid (IL): methyltrioctylammoniumbis(trifluoromethylsulfonyl)imide ([MOA]+[Tf2N]−). The binary systems were ([MOA]+[Tf2N]− + ethyl acetate or ethanol). The apparent molar volume, Vφ, and the apparent molar isentropic compressibility, kφ, have been evaluated from the experimental density and speed of sound data, respectively. A Redlich–Mayer equation was fitted to the apparent molar volume and apparent molar isentropic compressibility data. The partial molar volume, View the MathML source, and partial molar isentropic compressibility, View the MathML source, of the binary mixtures have also been calculated at each temperature. The partial molar volume indicates that the intermolecular interactions for (IL + ethanol) are stronger than for (IL + ethyl acetate) at all temperatures and View the MathML source for both systems increases with an increase in temperature. The values of the infinite dilution apparent molar expansibility, View the MathML source, decreases with an increase in temperature. The isentropic compressibilities, ks, increases with an increase in temperature for both binary systems. Positive View the MathML source, for both binary systems can be attributed to the predominance of solvent intrinsic compressibility over the solute intrinsic effect.
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    Ternary excess molar volumes of {methyltrioctylammonium bis(trifluoromethylsulfonyl)imide + ethanol + methyl acetate, or ethyl acetate} systems at T = (298.15, 303.15, and 313.15) K
    (Elsevier, 2010-01-28) Gwala, Nobuhle V.; Deenadayalu, Nirmala; Tumba, Kaniki; Ramjugernath, Deresh
    The activity coefficient at infinite dilution for 30 solutes: alkanes, alkenes, cycloalkanes, alkynes, ketones, alcohols, and aromatic compounds was determined from gas–liquid chromatography (glc) measurements at three temperatures (303.15, 313.15, and 323.15) K. The ionic liquid: trioctylmethylammonium bis(trifluoromethylsulfonyl)imide, was used as the stationary phase. For each temperature, values were determined using two columns with different mass percent packing of the ionic liquid. The selectivity value was calculated from the to determine the suitability of the solvent as a potential entrainer for extractive distillation in the separation of an hexane/benzene mixture, indicative of a typical industrial separation problem for benchmarking purposes.