Modelling the kinetics of direct Cu(II) adsorption on two porous resins modified with mussel-inspired chemistry

Two synthetic resins (i.e. Dowex Optipore V493 (DOV493) and XAD7) were subjected to a physical surface modification with mussel-inspired chemistry. Kinetics of direct Cu(II) adsorption were studied and the experimental data were modeled according to some adsorption kinetic models. The studied kinetic models suggested ( i ) diffusion-controlled and ( ii ) adsorption-controlled mechanisms for the direct adsorption of Cu(II) on PD-DOV493 and PD-XAD7, respectively. Regardless of the rate-limiting step, the studied two polymeric resins (i.e. DOV493 and XAD7) could be converted to new forms capable of binding Cu(II), which in their original form is impossible. Equilibrium adsorption capacities around 70 µg/g and 500 µg/g were determined to be accessible for PD-DOV493 and PD-XAD7, respectively, at relatively low initial Cu(II) concentrations (i.e. ~ 1–3 ppm). It is believed that the obtained results will be useful for understanding the nature of heavy metal adsorption kinetics on PD-coated porous polymeric resins.