Abstract  :

Heavy metal ion adsorbent (C-4-bromophenylcalix[4]resorcinarene) was successfully synthesized. Several heavy metal ions including lead (Pb (II)), cobalt (Co (II)), copper (Cu (II)), manganese (Mn (II)), and zinc (Zn (II)) were selected to evaluate the adsorbent efficiency of the newly synthesized adsorbent. Various parameters such as adsorbate dose, agitation time, and solution’s pH were optimized to approach the maximum removal efficiency. In addition, the adsorbent performance was analyzed against two kinds of solutions containing individual and mixture of the selected heavy metal ions. It was observed that the maximum efficiency could be obtained by adjusting the pH of the solution to 5.6 and 30 min contact time. This results in the decrease of the cation removal percentage by the applied adsorbent. As the results show, a 30 min contact time was sufficient to achieve maximum adsorption of the selected heavy metal ions on the synthesized adsorbent. Among the three models, the pseudo-2nd order kinetics was more consistent with the obtained experimental data. Therefore, the pseudo-2nd order model is better suited to explain the kinetics of the heavy metal ions on the synthesized adsorbent. Analysis of the solutions containing the individual heavy metal ions revealed that the adsorption capacity increased as Cu (II) > Pb (II) > Zn (II) > Mn (II) > Co (II). However, the capacity adsorption ranking of Cu (II) > Co (II) > Mn (II) > Pb (II) > Zn (II) was observed for the heavy metal ion mixture. Furthermore, the rate constant value, obtained through the Ho pseudo-second-order model, was ranked for the metal ions as the following: Co (II) > Cu (II) > Zn (II > Mn (II) > Pb (II).