Modelling CCC Using an Eluting Countercurrent Distribution Model

Abstract

As countercurrent chromatography (CCC) is becoming an established method in chromatography for scaling from analytical CCC in the laboratory to full process scale in the industrial manufacture of products, it is becoming increasingly important to model the process and to be able to predict coil/column scale‐up parameters for a given process. This paper offers a method of modelling CCC on the basis of an eluting countercurrent distribution (CCD) model. The model confirms that peak width in CCC varies in proportion to the square root of the length of the column, establishes a formula predicting peak width in terms of retention factor and retention time, and provides a method for determining the efficiency of a given CCC instrument. This allows, for the first time, the mixing efficiency of different CCC approaches and/or devices to be compared and perhaps, more importantly, predictions to be made that are outside the current operating parameters of existing CCC instrumentation. This will greatly assist in the design of new equipment, particularly in scale‐up, and will also help users optimize the results from their CCC instruments.

Keywords:

• CCC
• CCD
• Liquid–liquid chromatography
• Modelling
• Distribution ratio
• Retention
• High resolution
• Scale‐up
• Distribution constant

Acknowledgments

The author would like to acknowledge the support of the Engineering and Physical Sciences Research Council (EPSRC Grant Nos. GR/R/03143/01 and GR/M48345‐ID13) and European Union (INTAS Grant Reference 000‐00782).