Liquid-Liquid Equilibrium (LLE) data were obtained for
the pseudo-ternary systems of propionic acid (PA) + water + solvents (methyl
isopropyl ketone and methyl isobutyl ketone) + salts (NaCl and KCl) at
25-26°C in order to study the effect of salts on extraction equilibrium
of these systems by comparing with the same systems without salt. Mutual
solubility curves, tie-line data, distribution coefficient, selectivity
diagrams and separation factor data were determined for these systems.
The salting-out effect was investigated by using inorganic salts NaCl
or KCl at two concentrations of each salt within their solubility limits.
The results obtained in these experiments showed that the salts NaCl and
KCl significantly affect the solubility of PA in the organic solvents,
as well as the distribution coefficients and separation factors for PA
by changing their equilibrium composition and the selectivity of the solvents
while the region of heterogeneity increases as compared to the same system
of without salt. The thermodynamic consistency of the equilibrium tie-line
data was ascertained by Othmer-Tobias plots as well as by Hand plots.