Synthesis of a novel magnetic chitosan-mediated GO dual-template imprinted polymer for the simultaneous and selective removal of Cd(Ⅱ) and Ni(Ⅱ) from aqueous solution

With the uptrend of the energy industry and Cadmium-Nickel batteries, the development and comprehensive utilization of highly efficient adsorptive material for simultaneous and selective capture of Cd(II) and Ni(II) ions are of great significance, but formidable. Herein, a dual-template imprinted nanoparticle material (MCTS@GO@DIIP) was synthesized on GO slice structure coated with MnFe2O4 magnetic chitosan film via surface ion-imprinted technique for selective removal of Cd(II) and Ni(II) from aqueous solution. The material was based on ion-imprinted condensates of chitosan, L-histidine and GO as ion recognition layer with Cd(II) and Ni(II) as dual-template ions, L-histidine as monomer and glutaraldehyde as crosslinking agent. The obtained MCTS@GO@DIIP was characterized by SEM, FT-IR, XRD and TGA to study the surface structure, group distribution, crystal structure and thermal property. The adsorption experiments exhibited the MCTS@GO@DIIP achieved adsorption equilibrium for Cd(II) and Ni(II) ions in 30 min with the maximum adsorption capacities of 33.91 and 39.35 mg g−1, respectively. The adsorption process was agreed with the pesudo-second-order kinetic model and Langmuir isotherm adsorption model, proclaiming monolayer chemisorption on homogeneous sites was the rate-limiting step. Meanwhile, the MCTS@GO@DIIP also showed a specificity recognition ability for Cd(II) and Ni(II) using analogues Co(II), Zn(II), Mg(II) and Pb(II) as interference. Moreover, the MCTS@GO@DIIP based MSPE could extract approximately 95.5–104.6% of Cd(II) with a RSD of 3.34–8.27%, and 90.0–103.4% of Ni(II) with a RSD of 3.21–7.03% in real water samples, which indicated the polymer had the high stability and reproducibility and presented itself a promising material for the Cd(II) and Ni(II) adsorption and detection from aqueous solution.