Collect. Czech. Chem. Commun. 1983, 48, 1390-1400

Isothermal dynamics of adsorption in diluted sorbent layers; The adsorber with an infinite sorption layer

Jindřich Stárek, Milan Kočiřík and Arnošt Zukal

The J. Heyrovský Institute of Physical Chemistry and Electrochemistry, Czechoslovak Academy of Sciences, 121 38 Prague 2


The phenomenological model of the adsorbate transport in isothermal adsorber with a constant diameter was solved for an infinite, static and statistically homogeneous and isotropic sorption layer of constant composition. The layer was formed by a mixture of the adsorbent and the inert material grains with identical form and size. The model applies the linear adsorption isotherm and accounts for contributions of the convection, axial dispersion, external and internal diffusion and rate of adsorption. The obtained Laplace's image of the solution was used for calculation of the statistical moments up to the fourth order. The analysis of the effect of dilution on the separation efficiency (characterized by a number of theoretical plates) has led to the conclusion that for equal amounts of the adsorbent, the more diluted layer will have higher efficiency, or, for equal separation efficiencies, the amount of the adsorbent in the more diluted layer will be lower than in the less diluted layer. It has been shown that the contribution of axial dispersion has a positive, primary effect on the separation efficiency.