Structure and hydrolytic durability of a glass containing waste from spent tributyl phosphate reprocessing

Abstract

The structure of the glass obtained by incorporation of the residue from reprocessing of the spent extractant, tributyl phosphate, into sodium aluminophosphate glass and the structural state of uranium in this glass were studied by vibration (IR, Raman) and X-ray absorption (XAFS) spectroscopy. An IR and Raman spectroscopic study shows that the structural network of the glasses is formed by ortho- and pyrophosphate groups linked by tetrahedral AlO₄ units. As follows from the XAFS data, uranium is present in the glass in the form of uranyl ions and of separate UO_2+x particles. The glass has high hydrolytic durability: The uranium leach rate determined in accordance with GOST (State Standard) R 52 126–2003 is of the order of 10^–8 g cm^–2 day^–1.