Effect of Solvents and Temperature on Interactions in Binary and Ternary Mixtures of 1‑Butyl-3-methylimidazolium Trifluoromethanesulfonate with Acetonitrile or/and N,N‑Dimethylformamide

• Published in: Journal of chemical and engineering data 2018-12, Vol.63 (12), p.4288-4305, Article acs.jced.8b00176
• Main Authors: Fatima, Urooj, Riyazuddeen, Anwar, Naushad
• Format: Article
• Language: English
• ISSN: 0021-9568; 1520-5134
• DOI: 10.1021/acs.jced.8b00176

The densities ρ, speeds of sounds u, and dynamic viscosities η of the pure ionic liquid (IL) 1-butyl-3-methylimidazolium trifluoromethanesulfonate ([BMIM]­[CF3SO3]), acetonitrile (ACN), N,N-dimethylformamide (DMF), and of their binary and ternary mixtures as a function of mole fraction of IL/solvent at various temperatures (298.15 to 323.15) K with an interval of T = 5 K and at P = 0.1 MPa have been measured experimentally. The excess molar volumes, V E, excess molar isentropic compressibilities, K S,m E and viscosity deviations, Δη have been determined from the measured data of ρ, u, and η of pure [BMIM]­[CF3SO3], ACN, DMF and of their binary/ternary mixtures at studied compositions and temperatures. We have also calculated the Gibbs free energy of activation, ΔG * and an excess Gibbs free energy of activation for viscous flow, ΔG *E for the studied binary mixtures. The V E, K S,m E and Δη of the studied binary/ternary mixtures are fitted to the Redlich–Kister polynomial equation. The trends of variations of parameters varied with mole fraction of IL and temperature and are discussed in terms of ion–ion, ion–dipole, and dipole–dipole interactions. In this work, we have also applied various semiempirical models to correlate the experimental dynamic viscosity data and evaluated interactional parameters of the studied binary mixtures. The excess molar volumes of each binary system have also been correlated with the Prigogine–Flory–Patterson (PFP) theory and have been found in good agreement with the experimental values.