Application of the Sclc Model to the Salt Effect in Vapor-Liquid Equilibria
The ability of the rationalized SCLC model to correlate data on the salt effect in vapor-liquid equilibria is examined in this work. Fora system consisting of two miscible solvents the effect of salt in altering the relative volatility is represented by the model with four adjustable binary interaction parameters. The model is shown to correlate vapor-liquid equilibria of several alcohol-water-salt systems satisfactorily. © 1995, Taylor & Francis Group, LLC. All rights reserved.
A modified self-consistent local composition model for the thermodynamic properties of single and mixed electrolytes
In the recently developed self-consistent-local composition (SCLC) theory (Ananth and Ramachandran, 1990) the osmotic and activity coefficients in single electrolyte solutions are expressed as sums of several independent contributions. In the present work, the approximate proportionality between certain pairs of these contributions is identified and the model is reformulated with fewer and more orthoganal parameters. The numerical difficulties experienced with the original model in the evaluation of parameters and in the extension of the calculations to mixed electrolyte systems are thus eliminated. The simplified model is shown to correlate the activity and osmotic coefficient data of large number of single and those of mixed electrolyte systems with good accuracy. The osmotic and activity coefficient of single electrolyte solutions are expressed in terms of two binary adjustable parameters and mixed electrolyte systems containing two salts and one solvent are expressed in terms of only one adjustable parameter in addition to the binary parameters determined from the component single electrolyte systems. The theory contains no additional adjustable parameters in the case of multielectrolyte (more than two salts) systems. The model is found to represent satisfactorily the behavior of electrolyte solutions at different temperatures with a single set of temperature-independent parameters.