A convenient adsorption kinetic equation has been offered for the modeling
of adsorption kinetics in batch systems when diffusion taking parts to the rate-controlling step
of adsorption. This model is suggested based on the Smoluchowski-Waite equation for diffusioncontrolled
second-order reactions. The proposed new model has better performance (lower
absolute values of the relative errors (AARE) %) respect to the pseudo-second-order. Results of
this equation are in agreement with experiment data especially at the initial times of adsorption
that diffusion contributes to the rate-controlling step of adsorption.
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