Adsorption of Zinc Ions from Aqueous Solutions on Polymeric Sorbents Based on Acrylonitrile-Divinylbenzene Networks Bearing Aminophosphonate Groups

Contamination of natural water sources with zinc ions poses serious ecological and health risks due to its toxicity and persistence. In this context, this study presents the preparation of new adsorbents based on acrylonitrile-divinylbenzene networks functionalized with aminophosphonate groups, selected for their strong chelating affinity towards Zn(II) ions. Both unmodified and functionalized materials were evaluated in adsorption experiments towards zinc ions. The adsorption capacity was evaluated as a function of the contact time and the initial zinc concentration. The functionalized adsorbents exhibited a significantly higher adsorption of zinc, attributed to the presence of aminophosphonate groups. In case of functionalisation with ethyl phosphonate group is achieved a maximum adsorption capacity of 101 mg/g. The equilibrium data followed the Langmuir isotherm, indicating monolayer adsorption, while the kinetic analysis followed the pseudo-second-order model, consistent with chemisorption. The optimal contact time was 60 min. Functionalized polymeric supports show strong potential for zinc ion removal, supporting their use in environmental remediation. Overall, the results demonstrate that aminophosphonate-functionalized polymers are highly effective adsorbents for the removal of zinc ions from contaminated waters.