This study investigated the density (ρ), speed of sound (u), and refractive index (nD) of binary mixtures of diethylene glycol monobuthyl ether (DEGBE) and 2-alkanols (C3–C6) at various compositions and temperatures (T=298.15, 308.15, 318.15 K) under normal pressure. The experimental data were used to compute derived properties such as excess molar volume (VmE), excess partial molar volume (V E m,i), deviationsin isentropic compressibility (Δ Ks), and in refractive index (ΔnD). These derived properties were fitted with the Redlich–Kister polynomial equation. A digital vibrating-tube densitometer (Anton Paar DSA 5000) was used to measure the density and speed of sound of pure substances and mixtures at different temperatures. The results revealed the intermolecular interactions and structure factors of the binary mixtures. Moreover, the Perturbed Chain Statistical Association Fluid Theory (PC-SAFT) model was applied to predict the density data of binary mixtures and compare them with the experimental data.
