Adsorption of RhB onto natural zeolite was experimentally and theoretically studied.

Two approaches to model an industrial fixed-bed adsorber were carried out.

First approach made use of equilibrium to describe adsorbate-adsorbent interaction.

Second approach made use of an apparent kinetics accounting for adsorbent diffusion.

Diffusion in natural zeolites modelling fixed-bed adsorbers has to be accounted for.