AN EMPIRICAL CORRELATION FOR SOLVENT SELECTIVITY FACTOR

An empirical formulation modifying the Nernst equation to incorporate the selectivity factor, beta, is tested with eighteen systems taken fr om literature to assess its reliability in correlating the LLE data. T his simple equation relates the selectivity factor to the ratio of the mass of the solvent to that of the diluent in the solvent phase. The correlation coefficient is almost unity for all the systems. The value of the intercept, ln(A), in the modified Nernst equation, ln(beta) = B ln (X(BB)/X(AB) + ln(A) is found to be in direct proportion with sol vent selectivity. The equation is also found effective in predicting t he salt effect in salt containing ternary liquid systems.