A Study on the Mixing Behavior of Glycerol with Aniline, Pyridine, and Piperidine over the Temperature Range 293.15 K to 323.15 K and Atmospheric Pressure

Experimental densities and sound speeds at temperatures (293.15, 303.15, 313.15, and 323.15) K and under atmospheric pressure are reported for glycerol + aniline, glycerol + pyridine, and glycerol + piperidine mixtures covering the entire composition ranges. Excess molar volumes and excess isentropic compressibilities were derived from experimental data and correlated using Redlich–Kister polynomial to test the quality of experimental data. Excess properties could be interpreted by considering the differences in molecular structure and hydrogen bonding capacity of the amines. This study utilized the Jouyban–Acree (J–A) model to capture both the compositional and temperature dependencies of mixture properties (density, sound speed, and their related properties, isobaric thermal expansivity, and isentropic compressibility). The average absolute percentage deviation of the correlated values from the experimental ones was better than 0.05 %, 0.011 %, 0.025 %, and 0.023 % for density, sound speed, isobaric thermal expansivity, and isentropic compressibility, respectively, attesting to the robustness of the J–A model to predict mixing behavior under varying conditions. The Perturbed Chain Statistical Associating Fluid Theory Equation of State (PC-SAFT EoS) was used to model the densities of the mixtures using a predictive approach. Schaaff's Collision Factor Theory (SCFT) and Nomoto's Relation (NR) were compared for their ability to model the speed of sound for the binary mixtures. The modeled densities showed good agreement with experimental data. NR outperformed SCFT in modeling speed of sound of current mixtures. The previous models (SCFT and NR) were coupled with PC-SAFT, because they require the input of liquid density data.