Influence of the temperature on the equilibrium phase diagram of the ternary system water + ammonium chloride + 2-propanol at 101.3 kPa

Highlights: • Multiphase equilibrium for water + NH₄Cl + 2-propanol. • Isothermal LL, SL and SLL equilibrium data at 298.1, 308.1, 313.1 and 333.1 K. • Isobaric LV, LLV, SLV and SLLV equilibrium data at the boiling temperature and 101.3 kPa. • The lowest temperature at which NH₄Cl can split water + 2-propanol into two liquid phases is 310.4 K. • Extended UNIQUAC have been used to model phase equilibrium including solid. -- Abstract: The phase equilibrium of the water + NH₄Cl + 2-propanol mixture, at a constant pressure of 101.3 kPa, has been determined isothermally at four temperatures, as well as at the boiling temperature. Transitions between the different regions of the isothermal equilibrium diagrams have been studied, and the lowest temperature at which the salt can split water + 2-propanol mixtures into two liquid phases, is found to be 310.1 K. As the temperature is increased from this critical value, the two-liquid-phase region expands until the boiling temperature is reached. Finally, the extended UNIQUAC model for electrolytes has been used to predict the equilibrium diagram of the system. Large discrepancies with the experimental results have been found, and it will, therefore, be necessary to review the parameters of the model based on the experimental data reported in this work.