Influence of water on the vapor–liquid equilibria, activity coefficients at infinite dilution and enthalpies of mixing for mixtures of N-methyl-2-pyrrolidone with C5 or C6 hydrocarbons

Reliable P–x and enthalpy of mixing data have been measured for the ternary systems 1-hexene+water+N-methyl-2-pyrrolidone (NMP), 3-methylcyclopentene+water+NMP, 3-methylpentane+water+NMP, 1-pentene+water+NMP, and 2-methylbutane+water+NMP at 90 °C, and for 1-hexene+water+NMP also at 140 °C using a static apparatus and an isothermal flow calorimeter, respectively. Activity coefficients at infinite dilution for the different hydrocarbons in the solvent have been derived from the P–x data in the dilute composition range, where the water content of NMP ranged between 0 and 6 wt.%. NRTL parameters have been fitted to the experimental data.