Published online by Cambridge University Press: 15 February 2011
Fluorapatite (Fap), Ca10(PO4)6F2, could be a potential candidate for the immobilization of radioactive isotopes thanks both to its physical-chemical properties and to the capability to incorporate mono-, di- and trivalent cations in its crystal structure. In this research work different preparation procedures able to incorporate in a fluorapatite matrix strontium in the form of nitrate or fluoride salt were considered. The experiments were performed by means of stable isotopes, as representative of the radionuclides contained in the nuclear fuel. Subsequently, the Sr-substituted fluorapatites (SrxFap), Ca10-xSrx(PO4)6F2, were characterized by X-ray diffraction, Raman spectroscopy, Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS). The results suggest that the considered synthetic procedures could be reasonably applied to the confinement of the radionuclides contained in some types of nuclear waste. In order to avoid the presence of unreacted reagents in the products or the formation of undesired phases, an optimization of the synthetic procedures may be considered.