Displacement chromatography, description

Of the various forms of liquid chromatography, that involving ion exchange would seem to be most amenable to a precise phyncochemical description since the mobile-phase/stationary-phase interaction amounts simply to displacement of one (matrix-bound) ion by another. However, the effects introduced by charged species render such systems even more intractable than is the case with non-electrolyte solutions. Nevertheless, we show in what follows that a rigorous expression can be written for the relevant equilibrium constant, and that this can be related directly to chromatographic retentions. 

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