The Thermodynamics of Chromatography - Other Thermodynamic Methods that are Used for Studying Chromatographic Systems > Optimum Operating Conditions for Chiral Separations in Liquid Chromatography > Effect of Temperature and Solvent Composition on the Optimum Velocity > Page 80

 

Effect of Temperature and Solvent Composition on the Optimum Velocity

The approximate function for the optimum velocity given by equation (43) does not take into account the effect of solvent composition and temperature on solute diffusivity. Consequently a more precise function for the optimum velocity will be employed, (see Book 9)viz.

                                             (50)

Values for (Dm) can be calculated (19), using the following equation,

                              

                                          (51)

where is the Diffusivity of the solute at temperature (Tx) and solvent composition (cx)
is the Diffusivity of the solute at the reference temperature (To) and solvent composition (co)
is the viscosity of the solvent at temperature (Tx) and solvent composition (cx)
and is the viscosity of the solvent at the reference temperature (To) and solvent composition (co)