Chemical Engineering Journal, Vol.74, No.3, 205-210, 1999
Isothermal vapour-liquid equilibria of 1-propanol-water-salt mixtures
Isothermal vapour-liquid equilibrium data at 60 degrees C for the system 1-propanol-water-salt were obtained using the headspace gas chromatography (HSGC) technique. Three different salts were investigated in this study; NH4Cl, NaCl and CaCl2. The results obtained showed that while 0.50 M NH4Cl or 0.50 M CaCl2 had no effect on the vapour-liquid-equilibrium (VLE) of this system, NaCl with the same molarity could alter the VLE of the system and shift its azeotropic point. The azeotropic point of the system was shifted from 40 mol% 1-propanol to about 60 mol% 1-propanol when NaCl was added under saturation conditions. Good agreement with the Furter equation was observed for the experimental data with NaCl under unsaturated conditions. The salt effect parameter calculated from the Furter equation was found to be a function of the liquid concentration.