Synthesis of maghemite nano-particles and its application as radionuclidic adsorbant to purify 109Cd radionuclide

Maghemite nano-particles were synthesized by a solid-state chemical reaction for its highly selective use as, cyclotron-produced, Cd-109 (462.9 days) purification method of choice. Cd-109 radiochemical separation starts with Ag activities precipitated with HCl 0.0015 M followed by, on a second step, Cd-109 separation from Cu carrier and Zn-65 (243.8 days) using Ca (NO3)(2) 0.01 M. Experimental parameters such, pH and sorbent concentration, on Cd-109 extraction efficiency were investigated. Phase morphology, nanostructure and size of nano-particles were studied by X-ray diffraction (XRD) and scanning electron microscopy (SEM). A 10-20 nm average grain size was derived from XRD line broadening and SEM data. Heat treatment on Fe3+:Fe2+ ratios equal to 2:1, produced powders, resulting in tetragonal (maghemite) structure at 300 A degrees C and rhombohedra (hematite) at 600 A degrees C. Cd-109 chemical and radionuclidic purity were determined by ICP-AES and HPGe detector gamma-ray spectrometry. The overall recovery and radionuclide purity were 80.0% from obtained 129.63 kBq/C MeV (70 kBq/mu Ah) initial activity and 91.4%, respectively.