Dispersion in Chromatography Columns - Effect of Mobile Phase Compressibility On the HETP Equation for a Packed GC Column > Page 39

The resistance to the mass transfer term for the stationary phase must be considered in isolation. The experimentally observed plate height (variance per unit length) resulting from a particular dispersion process [e.g., (hs), the resistance to mass transfer in the stationary phase] will be the sum of the local plate height contributions (h');  i.e.,

                                  

Consequently, substituting for (h') the expression for the resistance to mass transfer in the stationary phase will be,

                  

 or                                           (24)

Now, it can be shown that, (see equation 23 in Plate Theory and Extensions),