The solubilities of three cinnamic acid esters, namely, methyl ferulate, methyl p-coumarate, and methyl sinapate, in eight imidazolium-based ionic liquids composed of the PF6 − and BF4 − anions have been measured at (30, 39, and 48) °C. Higher solubilities of the three esters were observed in the ionic liquids composed of the BF4 − anion than those composed of the PF6 − anion. Also, higher solubilities are observed in alkyl-substituted (on the imidazolium cation moiety) ILs than in polar-substituted ILs, whereas, as the alkyl chain length on the cation moiety increases, the solubility increases as well. Moreover, using the van’t Hoff equations, the apparent Gibbs energy, enthalpy, and entropy of solution were calculated. Positive values of the three thermodynamic functions were found in all cases. Finally, successful correlations of the experimental data were achieved with the UNIQUAC and the NRTL activity coefficient models.

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The solubilities of three cinnamic acid esters, namely, methyl ferulate, methyl p-coumarate, and methyl sinapate, have been measured in tert-butanol, tert-pentanol, ethyl acetate, and n-hexane, at the temperature range of (303.15 to 321.15) K. It is shown that tert-pentanol is the best solvent for methyl p-coumarate and methyl ferulate and ethyl acetate for methyl sinapate, while the nonpolar n-hexane is the worst solvent. Using the experimentally measured solubilities, the thermodynamic properties of dissolution of the three esters have been calculated. To better understand the solubilization process, the melting temperatures and the enthalpies of fusion of the three esters were determined by differential scanning calorimetry. Finally, successful correlation of the experimental data was achieved with the UNIQUAC and the nonrandom twoliquid (NRTL) activity coefficient models.

As a part of a series of studies that aim to expand the experimental database used to assist the design of novel technologies in the field of subsea gas processing, 18 new vapor–liquid equilibrium data points were measured for the system triethylene glycol (1) + water (2) + methane (3) at 6.0 and 12.5 MPa, temperature range between 288 and 323 K, and a glycol content above 95 wt %. The new data include both gas [glycol (y 1) and water (y 2)] and liquid [methane solubility (x 3)] phase composition, with relative experimental uncertainties below 18%. It was observed that one of the experimental data sets available in the literature is not in agreement with the experimental data measured in this work. Furthermore, an important target was to reevaluate the cubic-plus-association (CPA) equation-of-state modeling capability, which has been previously used for triethylene glycol–methane systems. CPA using a 4C association scheme for TEG and one interaction parameter per binary has provided a good description of the newly measured data, with the average absolute relative deviation ranging between 9 and 43%. Binary interaction parameters regressed solely from the corresponding binary data were used for all ternary predictions with CPA.