Thermophysical properties of binary mixtures of pentyl acetate with butanol at 298.15 K to 318.15 K: PFP theory, FTB model, and graph theoretical approach

Abstract

The measured density (ρ) and refractive index (nD) of binary pentyl acetate (1) + isomers of butanol (2) mixtures were reported at T = 298.15 K to 318.15 K and at 0.1 MPa pressure. Using the experimental ρ, u and nD data, excess molar volume (VmE), excess ultrasonic speed (uE), excess isentropic compressibility (κSE), and excess refractive index (nDE) were calculated and correlated with the Redlich–Kister (RK) equation. The findings suggest that the behavior of a mixture is affected by intermolecular interactions (cohesive forces such as dipole–dipole, H–bonding, dispersive force) and structural aspects of the molecules. The Prigogine–Flory–Patterson (PFP) theory, Flory–Treszczanowicz–Benson (FTB) model, and Graph theoretical approach (GTA) accurately analyzed the VmE values. Both the FTB model and PFP theory predicted the VmE curves not only successfully but also accurately represented their shape and magnitude except GTA at a lower mole fraction of pentyl acetate (xA<0.2). The positive values of VmE values were observed for binary mixtures across all temperatures. The intermolecular interactions were also corroborated by uE, κSE and nDE.