THEORY OF OPTIMIZATION OF IDEAL DISPLACEMENT CHROMATOGRAPHY OF BINARY-MIXTURES

The optimization of the displacement chromatographic separation of binary mixtures for maximizing the column throughput was investigated. The theory of coherence, based on the compound Langmuir model, was used to establish the general behavior of displacement chromatography through the use of distance-time diagrams. It is shown that columns should be operated at their resolution point for maximum throughput, and this is applicable to non-ideal displacement chromatography. Concentration of the feed sample to an optimum value is necessary to maximize the column throughput. The effects of the separation factor, capacity factors and resin saturation capacity with respect to throughput were also investigated. An analysis of the displacer affinity showed that low-affinity displacers are generally desirable in terms of development, regeneration and solubility requirements. A simple method is proposed for determining the optimum column loading for a given separation, and the extension of this approach to multi-component mixtures is discussed. This method can be used for the optimization of displacement separations of systems approximated by the compound Langmuir model.