One-step synthesis of CDTA coated magnetic nanoparticles for selective removal of Cu(II) from aqueous solution

A novel 1,2-cyclohexylenedinitrilotetraacetic acid (CDTA) modified Fe3O4 magnetic nanoparticles (MNPs) was synthesized by one-step solvothermal method and used as solid phase extraction (SPE) material to preconcentrate trace copper coupled with flame atomic absorption spectrometry (FAAS). The synthesized adsorbents were characterized by field emission scanning electron microscopy and X-ray powder diffraction with a nanoscale. The optimum conditions for the absorption process were investigated on several commonly tested experimental parameters such as pH of the solution, ultrasound time, sample volume, concentration and volume of elution solution. The influences of some anions and cations on the recoveries of Cu(II) ions were also investigated, and no considerable interference was observed. The maximum adsorption capacity of Fe3O4 magnetic nanoparticles and CDTA modified Fe3O4 magnetic nanoparticles were found to be 27.50 mg/g and 78.24 mg/g for Cu(II). The developed method was applied to the determination of Cu(II) in tap and lake water samples with recoveries ranging from 96.4% to 99.1%.