Fabrication of a novel hydrophilic ion-imprinted polymer based on silica-modified magnetic graphene oxide as a sensitive sorbent for the fast separation of silver ions from aqueous media

Abstract

This paper aimed to evaluate the co-precipitation preparation of a novel magnetic graphene oxide ion-imprinted polymer (IIP) for the recognition and separation of silver ions in aqueous solutions. The synthesis of this adsorbent was established by thermal copolymerization of 4-vinyl pyridine (4-VP) as a functional monomer, salen as a ligand, silver ions as a template ion, ethylene glycol dimethacrylate (EGDMA) as the crosslinking agent, acetonitrile and chloroform as the solvents, 2,2-azobisisobutyronitrile (AIBN) as an initiator by coating on the surface of magnetic graphene oxide as a magnetic core. The prepared polymer was morphologically characterized by the use of several characterization techniques. A batch-wise adsorption investigation was carried out to determine favorable conditions for proper adsorption, likewise selectivity and reusability. The kinetics of the adsorption process was pseudo-second order and followed the Langmuir isothermal model. The maximum adsorption capacity was 77.6 ± 0.6 mg g−1 at a pH of 4. The involvement of other competing ions revealed that the adsorbent benefits from the selective property of the imprinted cavities.