Isobaric vapor-liquid equilibrium for the binary mixtures (2-butanol plus n-hexane) and (2-butanol plus 1-butylamine) and for the ternary system (2-butanol plus n-hexane plus 1-butylamine) at 101.3 kPa

Isobaric vapor-liquid equilibrium has been experimentally studied for the binary mixtures 2-butanol + n-hexane and 2-butanol + 1-butylamine and for the ternary mixture 2-butanol + n-hexane + 1-butylamine at 101.3 kPa. The activity coefficients were found to be thermodynamically consistent, and they were satisfactorily correlated with the Margules, van Laar, Wilson, NRTL, and UNIQUAC equations. The activity coefficients were also compared with the results obtained from the application of the ASOG and modified UNIFAC group contribution methods. The boiling points of the solutions were correlated with compositions by the Wisniak-Tamir equations. The results obtained indicate that the binary system 2-butanol + n-hexane deviates positively from ideality, whereas 2-butanol + 1-butylamine deviates negatively from ideality. The ternary system deviates positively or negatively depending on the composition. Only the binary systems present azeotropy. Azeotropic behavior was not found in the ternary mixture.