Influence of the concentration dependence of the mass transfer properties on the chromatographic band profiles I. Apparent axial dispersion coefficient in frontal analysis

Abstract

The influence of the concentration dependence of axial dispersion on the profiles of breakthrough curves was studied using the equilibrium-dispersive model. A simple linear relationship between the apparent axial dispersion coefficient and the concentration was assumed and calculations of band profiles were carried out for both increasing and decreasing values of the axial dispersion coefficient with increasing concentration. A comparison of the profiles with those obtained with a constant coefficient shows that the effect of a concentration dependence is significant even for moderate variations.