Experimental P–ρ–T Data and Modeling for Butan-2-ol + n‑Octane or n‑Decane in the Ranges of 313.15–353.15 K and 0.1–20 MPa

Experimental density data at high pressures for two novel binary systems, butan-2-ol (1) + n-octane (2) and butan-2-ol (1) + n-decane (2), are presented in this work. Measurements were conducted in the temperature and pressure ranges of 313.15–353.15 K and 0.1–20 MPa, respectively, and include the entire mixture composition range. The experimental data were successfully correlated utilizing the modified Toscani–Szwarc equation of state and comply with generally expected trends with regard to temperature and pressure. The data were also modeled by the Peng–Robinson equation of state and predicted by the perturbed chain statistical associating fluid theory (PC-SAFT) model; however, a poor representation of the data was observed for the mixtures. Excess molar volumes, thermal expansivity, and isothermal compressibility were calculated using the regressed model parameters and are also presented. Significant deviations from ideality regarding the calculated excess volume is mainly attributed to different molecule shapes and sizes, intermolecular mixture interactions, free volume changes, and interstitial accommodation.