Properties and structure of vitrified iron phosphate nuclear wasteforms

摘要: The structure of vitreous iron phosphates containing up to 35 wt% one or more common nuclear waste components such as Na2O, Cs2O, SrO, UO2 Bi2O3 have been investigated using Fe-57 Mossbauer, X-ray absorption, photoelectron and Raman spectroscopies high energy neutron diffraction techniques. glass samples were prepared by melting appropriate chemicals in air at approximately 1200°C for 2 h alumina crucibles. chemical durability the glasses was measuring their dissolution rates distilled water 90°C product consistency test (PCT) methodology. these is characterized 10−10–10−11 g/cm2/min. Mossbauer spectra indicate presence both Fe(II) Fe(III). However, maximum fraction, Fe(II)/[Fe(II) + Fe(III)], 0.34. absorption data show that, on average, species ions are coordinated with 5 near neighbor oxygens that iron–oxygen coordination only slightly (<10%) influenced type concentration elements. Iron also 4–6 phosphorous second shell. Only a minority oxygen ions, about 22%, take part bridging –P–O–P– bonds. phosphorous–oxygen network, which dominated (P2O7)4− dimer units, different similar.