Equilibrium of Separation

EQUILIBRIUM OF SEPARATION. If we allow a system of two immiscible liquids, containing a solute (i) to come to equilibrium, we can express our equilibrium distribution coefficient, Kc, as 

The ratio of the total amount of solute in phase 2 to the total amount of solute in phase 1 is known as the capacity factor and is given the symbol, k, thus 

We cam introduce another term, which is used a great many times in chromatography, that of phase ratio, (5. It is the ratio of the volumes of the two phases  

Another way to consider the efficiency of an extraction system is to present the data in terms of the fraction of solute extracted and the fraction unextracted. The fraction of total solute in a given phase, ) , can be written 

We may now derive equations for the fraction of solute extracted, 4 2, and the fraction unextracted, (1 - 4 2) - Therefore 

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