Design and synthesis of novel chitosan–based nanocomposite containing mesoporous nanosilica MCM-41: Effective absorbent for the elimination of Pb (II) from aqueous solution

Abstract

A novel chitosan–based nanocomposite containing mesoporous nanosilica MCM-41 was synthesized, and its application as a good adsorbent for Pb (II) ions was investigated. In this context, MCM-41 was modified by 3-(Triethoxysilyl)-propylamine (3-APTES) to prepare MCM-41-NH2, and then MCM-41-NH2-graft-polyarcrylamide-co-polyacrylic acide-graft-chitosan [(MCM-41-NH2-g-poly(AAm-co-AA)-g-CS] nanocomposite was fabricated by in situ polymerization. The morphology and structure of nanocomposite were characterized by FT-IR, FE-SEM, EDS, XRD, AAS and TGA analysis. The results exhibited that active functional groups such as (-NH2) and (-COOH) on the nanocomposite surface reacted with Pb (II) ions via coordination bond. Maximum Pb (II) ion removal was seen at pH (6). The Pb (II) concentration and reaction time were 60 mg L−1 and 75 min as optimum conditions. Kinetics studies exhibited that adsorption experimental data were well adjusted to Langmuir isotherm, and the adsorption process onto polymer followed the pseudo-second order kinetics. As a result, it is expected that the synthesized nanocomposite can provide a promising prospect in the field of wastewater treatment.