Physicochemical Properties of Binary Mixtures of the Protic Ionic Liquid Bis(2-hydroxyethyl)methylammonium Formate with Methanol, Ethanol, and 1-Propanol

Densities and viscosities were determined for binary mixtures containing the protic
ionic liquid bis(2-hydroxyethyl)methylammonium formate [BHEMF] with methanol,
ethanol, and 1-propanol at four different temperatures (293.15, 303.15, 313.15, and
323.15 K) and atmospheric pressure. Excess molar volume and viscosity deviations for
the binary system were calculated. The calculated results were fitted to a Redlich-Kister
equation to obtain the coefficients and estimate the standard deviations between the experimental
and calculated quantities. The negative values of excess volume molar for these
mixtures indicate that ion-dipole interactions and packing between ionic liquids and alcohols
are present. The values of viscosity deviation are also negative over the whole composition
range, and their values become less negative as the temperature increases.