Temperature dependence of limiting activity coefficients, Henry's law constants, and related infinite dilution properties of C4–C6 isomeric n-alkyl ethanoates/ethyl n-alkanoates in water. Measurement, critical compilation, correlation, and recommended data

• Published in: Fluid phase equilibria Vol. 375; pp. 347 - 359
• Main Authors: Fenclová, Dana, Blahut, Aleš, Vrbka, Pavel, Dohnal, Vladimír, Böhme, Alexander
• Format: Journal Article
• Language: English
• Published: Elsevier B.V 15.08.2014
• Subjects: Activity coefficients; Alkyl alkanoates; Aqueous solution; Constants; Correlation analysis; Dilution; Esters; Henry law; Henry's law constant; Infinite dilution activity coefficient; Mathematical models; Temperature dependence; Temperature dependence; Henry's law constant; Aqueous solution; Infinite dilution activity coefficient; Alkyl alkanoates
• ISSN: 0378-3812; 1879-0224
• DOI: 10.1016/j.fluid.2014.05.023

•Limiting activity coefficients of C4–C6 alkyl alkanoates in water were measured.•Literature data on ester dissolution energetics in water were critically reviewed.•Phase equilibrium and related thermal data were simultaneously correlated.•Recommended data were established in the range from (273 to 373)K.•Variation of thermodynamic functions with T and ester structure was overviewed. Infinite dilution activity coefficients (γ1∞) of C4–C6 isomeric n-alkyl ethanoates/ethyl alkanoates, namely ethyl ethanoate, propyl ethanoate, ethyl propanoate, butyl ethanoate, ethyl butanoate in water were measured at several temperatures in the range from (273 to 361)K. Most measurements were carried out by the inert gas stripping method, although other three headspace gas chromatography techniques were also employed. A comprehensive critical review is further presented of literature data on γ1∞, infinite dilution partial molar excess enthalpies (H¯1E,∞) and heat capacities (C¯p,1E,∞) of these aqueous solutes. For each ester, the data measured in this work together with those reported previously in the literature were correlated with a suitable model equation providing adequate simultaneous description of the equilibrium measurements and the calorimetric information. As a result, a recommended temperature dependence of γ1∞ of superior accuracy was established. The consistency of recommended γ1∞(T) with literature data on mutual solubilities of esters and water was also demonstrated. Analogous recommendations were derived also for the temperature dependence of Henry's law constants (KH). The variation with temperature and ester molecular structure of γ1∞, KH, and related energetic functions of ester dissolution and hydration was overviewed and briefly discussed. Furthermore, the performance of five predictive approaches to estimate γ1∞(T) of the aqueous esters was tested.