3.6. Kinetic modeling
The kinetics of adsorption is an important characteristic to define the efficiency of adsorption. In order to investigate the mechanism of adsorption and kinetic parameters sorption data was analyzed using pseudo-first order [33] and [34], pseudo-second order [35] and [36], and intraparticle diffusion [37] models which are described in Table 2.
Pseudo-first order, pseudo-second order, and intraparticle diffusion kinetic parameters are represented inTable 5. The correlation coefficient for the pseudo-second order kinetic model was higher than the other models (R2 = 0.999) for both Ni(II) and Co(II) ions indicating that the adsorption perfectly complies with pseudo-second order reaction and the adsorption process appeared to be controlled by the chemisorption process. In addition, the theoretical qe values found from the second-order kinetic model are in accordance with the experimental qe values.