New copolymers with triazole pendant groups: Synthesis, characterization and their application to remove heavy metals

Abstract

Copolymers obtained from polyvinyl alcohol (PVA) containing substituted triazole pendant groups were synthesized via “click” reactions. The chemical structures of the new copolymers with hydroxylmethyl (PVATPHM) or protected galactosyl groups (PVATPGal) as substituents were characterized by spectroscopical analysis (FTIR, 13C NMR, and 1H NMR spectroscopies) as well as the thermal properties were analyzed by TGA and DSC techniques. Interactions studies with heavy metal ions, such as Cd2+, Zn2+, Hg2+, and Cu2+, in aqueous solutions were carried out. Ion sorption was evaluated taking into account pH, time, and concentration. Results of competitive selectivity assays were also analyzed. PVATPHM was capable to remove all the analyzed metal ions in different experimental conditions. Furthermore, the PVATPGal showed excellent capacity for lead removal with maximum adsorption capacity at pH 1.0 and the heavy metal can be desorbed using ethylenediaminetetraacetic acid.