Removal of Heavy Metal Ions using New Chelating Material Containing N, O, and S Donor Sites

Abstract

A new chelating material (AT‐PHE‐HCHO) was synthesized by reacting 2‐aminothiazole‐phenol (AT‐PHE) azodye and formaldehyde (HCHO) in an alkaline medium. The materials were characterized by elemental analysis, FT‐IR and ¹H‐NMR spectroscopic studies. The chelating material was used for the adsorption of Cu(II), Zn(II), Mn(II), and Cr(III) from dilute aqueous solutions with variation of adsorption parameters. The adsorption was described quantitatively by fitting the equilibrium data to the Freundlich isotherm. The thermodynamic parameters ΔS and ΔH were calculated to be 86.02 J mol⁻¹ K⁻¹ and −126.9 KJ mol⁻¹, respectively. The metal adsorption followed the sequence Cu(II)>Zn(II)∼Cr(III)>Mn(II). The material was used for the removal of metal ions from synthetic as well as real samples.

Keywords:

• Adsorption
• isotherms
• chelating
• removal

Acknowledgments

The authors wish to acknowledge financial support (Grant No.: F12‐32/04) of University Grants Commission (UGC), New Delhi, to carry out the project work. Analytical results obtained from the Central Drug Research Institute (CDRI), Lucknow, are thankfully acknowledged.