Immobilization of Two Azacrown Ethers on Chitosan: Evaluation of Selective Extraction Ability Toward Cu(II) and Ni(II)

Abstract

Two Schiff base-type chitosan-azacrown ethers were prepared by a reaction of chitosan (CTS) with N-(4′-formylphenyl)aza-crown ethers, and they were converted to secondary-amino derivatives by the reduction of CTS-azacrown ethers with sodium borohydride. Their structures were confirmed by elemental analysis, infrared spectra and thermogravimetric analysis. The ability of these adsorbents to extract Cu(II) and Ni(II) ions from water by a solid-liquid extraction process was studied. The effects of adsorbent amount, contact time and pH on the adsorption of CTS-azacrown ethers were investigated. The extraction results showed that CTS-azacrown ethers had good sorption capacities for Cu(II) ions in the coexistence of Ni(II) ions.

Keywords:

• Chitosan
• modification
• heavy metal
• macrocyclics
• ion binding
• solid-liquid extraction

Acknowledgment

Financial support for this research from the Research Foundation of Selcuk University (BAP 06101006) is gratefully acknowledged.

Notes

^a C₃ and N₃ are the found value of sample by elemental analysis.

^a Second stage.