Scale Chromatography

School of Chemical Engineering Purdue University West Lafayette, Indiana 

Immediately following the development of analytical chiomatogtaphic methods there was considerable interest in large-scale applications of these techniques for sqraration of compounds on a commercial scale. Although there were some repoits of large-scale uses, interest decreased when it became clear that large- 

In this section we are concerned first with the rate of movement of solute and second with the effects that broaden txmes in linear systems. More detailed mathematical presentations are available in the references. 

The equations for rate of solute movement can be derived rigotously, - but a phyncal aigumoit is used here. In all types of chromatography, die solute distributes between the statkmaiy diase and the mobile phase. When solute is in the stationary phase, its velocity with respect to the solid is zero, while when the solute is in the mobile phase, it has the same relative velocity as the moving fluid. Thus, we can calculate die solute velocity ftom the ftaction of time the solute spmids in the mobile phase 

Consider an experiment where an incremental mass of solute is added to the bed segment shown in Fig. 14.1-1. Then the fraction in the mobile phase can be calculated as 

To use Eq. (14.1-3) to predict solute movement in a variety of chromatographic systems. Aq must be related to Ac,. The easiest way to do this is to assume that solid and fluid phsses are in equilibrium, If 

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The chromatogram can finally be used as the series of bands or zones of components or the components can be eluted successively and then detected by various means (e.g. thermal conductivity, flame ionization, electron capture detectors, or the bands can be examined chemically). If the detection is non-destructive, preparative scale chromatography can separate measurable and useful quantities of components. The final detection stage can be coupled to a mass spectrometer (GCMS) and to a computer for final identification. 

Other modes of operation, including recycle and flow reversal schemes and continuous chromatography, are discussed in Ganetsos and Barker (Preparative and Production Scale Chromatography, Marcel Dekker, New York, 1993). 

These ideas and methods of preparative selective up-scale chromatography suggest that the use of new types of biosorbents and, in particular cellosorbents, and the application of theoretically based conditions for stepwise desorption of the components is an important new approach to preparative chromatography. 

Preparative and Production Scale Chromatography, edited by G. Ganetsos and P. E. Barker... 

E. Grushka (Ed.), "Preparative-Scale Chromatography", 0ekker New York, MY, 1989. 

Detection requirements in preparative-scale chromatography also differ from analytical erations where detectors are selected for their sensitivity. Sensitivity is not of overriding importance in preparative-scale chromatography the ability to accommodate large column flow rates and a wide linear response range are more useful. The sensitivity of the refractive index detector is usually quite adequate for prqtaratlve work but the ... 

So far we have considered preparative-scale chromatography when the column is not overloaded and the desired amount of ,sample... 

Ruthven, D.M. and Ching, C.B. (1993) Modeling of chromatographic processes. Preparative and production scale chromatography. In Chromatographic Science Series, Vol. 61. Eds. Ganetos, G., Barker,... 

Sardin M,Schweich D,Villermaux J (1993) In Ganestos G, Barker PE (eds) Preparative and production scale chromatography. Marcel Dekker, New York, pp 477-521... 

Balannec B, Hotier G (1993) From batch to countercurrent chromatography. In Ganetsos G, Barker PE (eds) Preparative and Production Scale Chromatography, Marcel Decker, New... 

Ganetsos, G. and Barker, P. E. Preparative And Production Scale Chromatography (Marcel Dekker, 1993) Hamada, J. S. J. Chromatogr. 760 (1997) 81. Large-scale high-performance liquid chromatography of enzymes for food applications. (Review)... 

RENDELL, M. Process Engineering (April 1975) 66. The real future for large-scale chromatography. 

Wankat, P. C. In Handbook of Separation Process Technology, Rousseau, R. W., ed. (Wiley, 1987) Chapter 14, Large-Scale Chromatography. 

Grushka, E., ed. Preparative-Scale Chromatography (Dekker, 1989). Reprinted from Sep. Sci. Technol. 22 (Nos. 8-10), (1987) 1791-2110. (Several articles in this volume deal with optimisation). 

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