Synthesis and characterization of Cyanex 272-modified supeparamagnetic magnetite nanoparticles

The in-situ polyethylene glycol coated superparamagnetic magnetite (Fe3O4) nanoparticles (SPMNPs) were prepared by a co-precipitation method from the acidic solutions of FeCl2.4H2O and FeCl3.6H2O, containing polyethylene glycol (PEG), using aqueous solution of  NaOH. The optimum coditions of the precipitation of  polymer coated magnetic nanoparticles were determinned.  It was found that the concentration of acid, sodium hydroxid, and polyethylene glycol influenced the size and structure of nanoparticles. The sizes and the size distribution, structure, and coating of  the nanoparticles were characterized by transmission electron microscopy (TEM), X-ray diffractometry (XRD), Fourier transform infrared spectrometry (FT-IR) and thermogravimetry analysis (TGA) techniques, respectively. The size of the uncoated nanoparticles was varied in the range of  8-28 nm and after the coating it did not change significantly. Finally, the modification of the particles was carried out simply by mixing the modifiere (Cyanex 272) with nanoparticles powder for a time duration of approximately one hour. The nanoparticle that was treated by Cyanex 272/SPMNPs of weight ratio of 7.5:1 possessed better characteristics for Uranium(VI) and Thorium(IV) recovery from aqueous solutions.