Biopolymer Encapsulation of PEI-Derivatives for Heavy Metal Sorption

Abstract

Composite materials have been synthesized by alginate or chitosan encapsulation of polyethylenimine (PEI) derivatives (obtained by glutaraldehyde grafting of histidine and carbon disulfide). Discrete or agglomerated PEI-derivative particles are immobilized in the macroporous network of biopolymer matrix (as shown by scanning electron microscopy and SEM-EDX analysis). The effect of pH and initial concentration on Zn (II) and Cu (II) sorption performance were analyzed. The incorporation of PEI-derivatives biopolymer matrix improves sorption performance in complex solutions (doped with CaCl2) compared to pristine biopolymer. Maximum sorption capacities range from 0.64 to 1 mmol L-1 for Zn (II) and from 1.13 to 1.67 mmol L-1 for Cu (II).