Techniques
CCC can be thought of as occurring in three stages: mixing, settling, and separation (although they often occur continuously). Mixing of the phases is necessary so that the interface between them has a large area, and the analyte can move between the phases according to its partition coefficient.
A partition coefficient is a ratio of the amount of analyte found in each of the solvents at equilibrium and is related to the analyte's affinity for one over the other. The mobile phase is mixing with then settling from the stationary phase throughout the column. The degree of stationary phase retention (inversely proportional to the amount of stationary phase loss or "bleed" in the course of a separation) is a crucial parameter. Higher quality instruments have greater stationary phase retention. The settling time is a property of the solvent system and the sample matrix, both of which greatly influence stationary phase retention.
Read more about this topic: Countercurrent Chromatography
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