Comparative and competitive adsorption of Pb(II) and Cu(II) using tetraethylenepentamine modified chitosan/CoFe₂O₄...

In this paper, tetraethylenepentamine (TEPA) modified chitosan/CoFe₂O₄ particles were prepared for comparative and competitive adsorption of Cu(II) and Pb(II) in single and bi-component aqueous solutions. The characteristics results of SEM, FTIR and XRD indicated that the adsorbent was successfully fabricated. The magnetic property results manifested that the particles with saturation magnetization value of 63.83emug^-1 would have a fast magnetic response. The effects of experimental parameters including contact time, pH value, initial metal ions concentration and coexisting ions on single and bi-component adsorption were investigated. The results revealed that the adsorption kinetic was followed pseudo-second-order kinetic model, indicating that chemical adsorption was the rate-limiting step. Sorption isotherms were also determined in single and bi-component solutions with different mass ratio of Cu(II) to Pb(II) (Cu(II)/Pb(II)) and fitted using Langmuir and Freundlich isotherm models. A better fit for Cu(II) and Pb(II) adsorption were obtained with Langmuir model, with a maximum sorption capacity of 168.067 and 228.311mgg^-1 for Cu(II) and Pb(II) in single component solution, 139.860 and 160.256mgg^-1 in bi-component solution (Cu(II)/Pb(II)=1:1), respectively. The present results suggest that TEPA modified chitosan/CoFe₂O₄ particles are feasible and satisfactory adsorbent for efficient removal of Cu(II) and Pb(II) ions.