A comprehensive review is presented of experimental data on the limiting activity coefficients γ1∞, infinite dilution partial molar excess enthalpies H¯1E,∞ and heat capacities C¯p,1E,∞ of lower 1-alkanols (C1–C5) in water. For each alkanol, the compiled data are critically evaluated and correlated with a suitable model equation providing adequate simultaneous description of the equilibrium measurements and the calorimetric information. As a result, recommended thermodynamically consistent temperature dependences of γ1∞, H¯1E,∞, and C¯p,1E,∞ of superior accuracy are established in the range from the melting point to the normal boiling point of water. In addition, by employing literature data on the respective residual properties of the pure 1-alkanols, analogous recommendations are also derived for the temperature dependences of the Henry’s law constants, hydration enthalpies, and hydration heat capacities. Evolution of the various infinite dilution thermodynamic properties of aqueous 1-alkanols with temperature and homologous series is briefly discussed.

Infinite dilution activity coefficients gamma(1)(infinity) and gas-liquid partition coefficients K(L) of 30 selected hydrocarbons, alcohols, ketones, ethers, esters, haloalkanes, nitrogen- and sulfur-containing compounds in the ionic liquid (IL) 1-ethyl-3-methylimidazolium nitrate [EMIM][NO(3)] were determined by gas-liquid chromatography at five temperatures in the range from 318.15 to 353.15 K. Relative contribution of adsorption at gas-liquid interphase to the overall solute retention, as examined by varying sample size and IL loading in the column, was found negligible. Partial molar excess enthalpies and entropies at infinite dilution were derived from the temperature dependence of the gamma(1)(infinity) values. The linear free energy relationship (LFER) solvation model was used to correlate successfully the KL values. The LFER correlation parameters and excess thermodynamic functions were analyzed to disclose molecular interactions operating between the IL and the individual solutes. In addition, the promising potential of [EMIM][NO(3)] for applications in solvent-aided separation processes was identified, the selectivities of [EMIM][NO(3)] for separation of aromatic hydrocarbons and thiophene from saturated hydrocarbons ranking among the highest ever observed with ILs or molecular solvents.

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Limiting activity coefficients (γ 1 ∞ ) of lower branched alkanols (2-propanol, 2-butanol, 2-methyl-1-propanol, and 2-methyl-2-propanol) in water were measured at several temperatures covering the range from the melting to the normal boiling point of water. Four experimental techniques (namely, headspace analysis, inert gas stripping, Rayleigh distillation, and the method of circulation still) were employed for the purpose. A comprehensive review is further presented of experimental data on the limiting activity coefficients (γ 1 ∞ ), infinite dilution partial molar excess enthalpies (H h 1 E,∞ ), and heat capacities (C h p,1 E,∞ ) of these aqueous solutes. For each alkanol, the compiled data were critically evaluated and together with the data measured in this work correlated with a suitable model equation providing adequate simultaneous description of the equilibrium measurements and the calorimetric information. As a result, a recommended thermodynamically consistent temperature dependence of γ 1 ∞ , H h 1 E,∞ , and C h p,1 E,∞ of superior accuracy was established in the range from the melting point to the normal boiling point of water. In addition, by employing literature data on the respective residual properties of the pure alkanols, analogous recommendations were derived also for the temperature dependence of the Henry's law constants, hydration enthalpies, and hydration heat capacities. Variation of these various infinite dilution thermodynamic properties of aqueous branched alkanols with temperature and alkanol branching is briefly discussed.