Speaker
Dr
EUGENIA KUO
(Australian Nuclear Science and Technology Organisation)
Description
Sodalites have been investigated experimentally for the capture and long-term containment of iodine-129, a significant and hazardous waste product of the nuclear fuel cycle. Sodalites are zeolite-type structures commonly occurring in nature in alkaline igneous rocks and having the prototype formula Na$_8$(AlSiO$_4$)$_6$Cl$_2$. The crystal structure is based around $\beta$-cages consisting of corner-sharing SiO$_4$ and AlO$_4$ tetrahedra. In the centre of the $\beta$-cage is an anion X. Iodine captured by sodalites sits in the centre of the $\beta$-cages as iodide anions. Silver iodide (AgI) plays an important role in the capture and subsequent processing of iodine-129 in the nuclear fuel cycle. Using *ab initio* density functional theory (DFT) modelling, we investigate the energetics and feasibility of iodine capture and containment in mixed cation sodalites Na$_{8-x}$Ag$_x$(AlSiO$_4$)$_6$I$_2$, and compare the results with experimental observations.
Primary author
Dr
EUGENIA KUO
(Australian Nuclear Science and Technology Organisation)