Synthesis and properties of cadmium(II)-imprinted polymer supported by magnetic multi-walled carbon nanotubes

A novel magnetic surface ion-imprinted polymer was developed by copolymerization of magnetic multi-walled carbon nanotubes as the core, 3-aminopropyltriethoxysilane (APTES) as the functional monomer and tetraethoxysilane (TEOS) as the cross-linker with chelating complexes of Cd(II). The Cd(II)-imprinted polymer was characterized by FT-IR spectroscopy, scanning electron microscopy (SEM) and a batch procedure. Under the optimized conditions, the maximum adsorption of Cd(II) was 27.90 mg g(-1) and the adsorption time was 70 min. The imprinted polymer showed higher selectivity for Cd(II) in comparison of the competitive adsorptions of Cd(II), Zn(II) and Cu(II) to the non-imprinted polymer. Relative selectivity factor (k') values of Cd(II)/Zn(II) and Cd(II)/Cu(II) were 15.44 and 14.32, respectively. The new Cd(II)imprinted polymer has been tested and applied for the separation and concentration of Cd(II) in tap water, with high recoveries ranging from 103.8% to 108.8%.