Preparation of ion imprinted magnetic Fe3O4 nanoparticles for selective remediation of Pb(II)

A novel Pb(II) imprinted magnetic polymer (Pb-IIMP) was synthesized by surface imprinting technique using Pb(II) as template, polyethyleneimine functionalized magnetic Fe3O4 (MNPs@PEI) as functional monomer and epoxy chloropropane (ECH) as cross-linker and applied for the remediation of Pb(II). Batch adsorption studies were performed to evaluate the influence of different sorption parameters, such as pH, initial concentration of Pb(II), contact time, adsorption selectivity and desorption. Isotherm and kinetics studies showed that the adsorption process obeyed Langmuir and pseudo-second-order models with a maximum adsorption capacity of 123.3 mg/g for Pb-IIMP and 62.2 mg/g for non-imprinted magnetic polymer (Pb-NIMP). The relative selectivity coefficients of Pb-IIMP for Pb(II)/Cd(II) and Pb(II)/Cu(II) were 1.2 and 1.4 times greater than Pb-NIMP. In addition, Pb(II) could be desorbed from Pb-IIMP by 0.5 mol/L HCl and used for five cycles without any adsorption performance loss, which revealed that the prepared PbIIMP had high stability and good reusability. (C) 2017 Taiwan Institute of Chemical Engineers. Published by Elsevier B.V. All rights reserved.