Physicochemical Properties of N-Butyl-N-methyl-2-oxopyrrolidonium Bromide and Its Binary Mixtures with Water or Methanol

Research output: Contribution to journalArticle


  • Indra Bahadur
  • Erlin Sapei
  • Sangeeta Singh
  • Eno E. Ebenso
  • G. G. Redhi

Research units

  • North West University
  • Durban University of Technology


Novel N-butyl-N-methyl-2-oxopyrrolidonium bromide ([BMpyr]+[Br]-) ionic liquid was synthesized and characterized by different techniques such as NMR (1H and 13C), FTIR, and HPLC. The measurements of thermophysical properties such as density, sound velocity, refractive index, viscosity, and conductivity of pure [BMpyr]+[Br]- were carried out at different temperatures from 293.15 to 343.15 K. Density, sound velocity, refractive index, and viscosity values decreases with increase in temperature whereas conductivity values increases. The density, sound velocity, refractive index, and conductivity data were fitted to the linear equation. Molecular volume data for cation and anion constituents of [BMpyr]+[Br]- were proposed from density correlation. On the basis of viscosity, some related parameters, like Vogel-Tammann-Fulcher, were calculated. Densities for the binary systems of the [BMpyr]+[Br]- with water or methanol were also measured at different temperatures. The intermolecular interactions between [BMpyr]+[Br]- and water or methanol were discussed.


Original languageEnglish
Pages (from-to)601-608
Number of pages8
JournalACS Sustainable Chemistry and Engineering
Issue number2
Publication statusPublished - 1 Feb 2016
MoE publication typeA1 Journal article-refereed

    Research areas

  • Conductivity, Density, Ionic liquid, N-Butyl-N-methyl-2-oxopyrrolidonium bromide, Physicochemical properties, Refractive index, Sound velocity, Viscosity

ID: 1508048