Study of molecular interactions in binary liquid mixtures containing tri-n-butylamine with 2-pentanone, 3-pentanone, and 4-methyl-2-pentanone: A thermophysical approach

This paper reports experimental densities (ρ) and speeds of sound (u) of tri-n-butyl amine (TBA), 2-pentanone (2P), 3-pentanone (3P), 4-methyl-2-pentanone (4M2P) and their binary mixtures with TBA as common component, measured at atmospheric pressure and T = (293.15, 298.12, 303.15, 308.15 and 313.15) K over the entire composition range. Experimental viscosities (η) under similar condition of composition and pressure are also reported at T = (298.15, 303.15, and 308.15) K. Excess molar volumes (VmE), excess isentropic compressibility (Δκs) and deviations in speed of sound (Δu) of all the binary mixtures were evaluated from the experimental results of density and speed of sound data. All these thermodynamic properties are analyzed in terms of intermolecular interactions and structural effects present between the molecules of the investigated binary liquid mixtures. Further, viscosity data were used to calculate deviations in viscosity (Δη) and excess Gibb's free energy of activation for viscous flow (ΔG⁎E). The derived properties have also been correlated to composition using Redlich-Kister type polynomial equation by the method of least-square for the estimation of the binary coefficients and the standard errors. Apart from this, various semi empirical relations i.e. Grunberg-Nissan, Tamura-Kurata, Katti-Chaudhri, McAllister (3-body interaction) and Heric-Brewer (3-parameter) have been tested using experimental viscosity data.