Phosphorus-containing compounds of pollucite structure and radiochemical problems

• Published in: Radiochemistry (New York, N.Y.) N.Y.), 2011-12, Vol.53 (6), p.593-603
• Main Authors: Loginova, E. E., Orlova, A. I., Mikhailov, D. A., Troshin, A. N., Borovikova, E. Yu, Samoilov, S. G., Kazantsev, G. N., Kazakova, A. Yu, Demarin, V. T.
• Format: Article
• Language: English
• Subjects: Chemistry; Chemistry and Materials Science; Chemistry/Food Science; Nuclear Chemistry
• ISSN: 1066-3622; 1608-3288
• DOI: 10.1134/S1066362211060051

New pollucite-like phosphorus-containing compounds with cesium and uni-, bi-, and trivalent cations (Li; Mg, Mn, Co, Ni, Cu, Zn, Cd, Sr, Ba; Al, Cr, Fe), many of which can be present in various combinations in wastes from radiochemical processes, were synthesized. The individual phases obtained were characterized by X-ray phase analysis and IR spectroscopy. The symmetry of the unit cells of the phosphorus-containing compounds decreases relative to the silicon analog (pollucite natural mineral) from Ia 3 d to I 4 1 32. The behavior of the compounds on heating to 1000°C, under hydrothermal conditions at 90°C, in aqueous systems (distilled water and seawater) at 25°C, and in a CsCl melt at 680°C was studied. The chemical and phase composition of the samples remained unchanged under all these conditions. The Cs leaching rates varied from 7.1 × 10 −6 to 1.46 × 10 −5 g cm −2 day −1 . The “crystal-chemical modeling” of the new possible compositions of the compounds with the expected pollucite structure was performed.