GC007 The chromatographic process - Part 3

 

The distribution constant or partition coefficient Kc, is a measure of the tendency of a component to be attracted to the stationary phase. In chromatography, the greater this value, the greater the attraction of that component to the stationary phase. The differences in distribution constants, which are controlled thermodynamically, are the responsible for chromatographic separations.

There are two types of sorption processes:

Absorption: sorption into the bulk of stationary phase

Adsorption: sorption on the surface of the stationary phase

One of these processes is usually dominant, but both can be present.

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