4.4. Immobilization kinetics
Predicting the rate at which the immobilization takes places on the surface of a given solid system is one of the most crucial factors for an effective immobilization design. Several kinetic models have been proposed to predict the behavior of the experimental data that take into account combined effects, such as transport, diffusion and adsorption/desorption of the solute molecules on a surface. Kinetic models that assume the “surface reaction” as the controlling step of overall sorption rate are based on the pseudo-first order, pseudo-second order and Elovich equations [35]. The pseudo-first and Elovich equations are restricted to the initial times of immobilization process and are not suitable for the description of the slow immobilization kinetics observed in this work.