Volumetric, acoustic and transport properties of binary mixtures of benzyldimethylammonium based ionic liquids with N,N-dimethylformamide at temperature from 293.15 to 328.15K

Abstract

The experimental density, ρ, speed of sound, u and viscosity, η values as a function of ionic liquid concentration, m for binary mixtures (benzyldimethylammonium propionate/benzyldimethylammonium hexanoate + N,N-dimethylformamide) were measured at T = 293.15 to 328.15 K and at atmospheric pressure. Apparent molar volumes, Vϕ, and apparent molar isentropic compressibilities, Ks,ϕ, have been determined from the experimental densities and speed of sound and fitted to a Redlich–Mayer equation for the calculation of limiting parameters (Vϕ∞ and Kϕ∞). The calculated Vϕ∞ and Kϕ∞ values indicate that ionic liquid–molecular solvent interactions are stronger for benzyldimethylammonium hexanoate (BDMAH) in DMF than the benzyldimethylammonium propionate (BDMAP) in DMF mixtures. The limiting apparent molar expansibilities, α at each temperature for both ionic liquids in DMF have positive values. The viscosity data have been analyzed using the Jones–Dole equation, and the derived parameters B and A have also been interpreted in terms of ion–solvent and ion–ion interactions.