# Preparative Chromatography - The Loading Capacity of a Column > Page 3

_{}

From the Plate
Theory (see
The Plate Theory and Extensions
), _{}, where (V_{m}) is the total volume of mobile
phase in the column or the column dead volume.

Thus: _{}

Now: _{}

where (r) | is the radius of the column, |

(L) | is the length of the column, |

(e) | is the fraction of the column containing solvent. |

Thus: _{}

Now (e) can be taken as approximately 0.6:

Thus,

and: (1)

The magnitude
of (A_{v}) will be determined by the nature of the separation, and (A_{m})
will be defined by the loading capacity of the stationary phase and, to some
extent, by the shape of the adsorption isotherm.