Synthesis and characterization of a novel Schiff base polyamide ligand and its copper(II) complex for comparative removal of Pb(II) ions from aqueous solutions

Abstract

A dicarboxylic acid Schiff base ligand was synthesized via condensation of 2-hydroxybenzaldehyde with 5-aminoisophthalic acid. The derived monomer was reacted with 4,4′-diaminodiphenyl ether and triphenyl phosphite (TPP) in tetrabutylammonium bromide (TBAB) molten ionic liquid as a green solvent to form an aromatic polyamide with a moderate yield (71%) and inherent viscosity (0.2 dL g−1). The nanostructured copper(II)/polyamide complex was then prepared. The structure, optical properties, and morphology of the compositions were confirmed by FT-IR, −1H-NMR, elemental analysis, UV-Vis, powder X-ray diffraction (XRD), thermogravimetric analysis (TGA) and field emission scanning electron microscopy (FE-SEM). The polyamide ligand and its nanostructured complex were comparatively applied in the elimination of Pb(II) ions from aqueous solutions.