Aqueous Processing of Thorium Fuels

Developments in reprocessing of spent nuclear fuels for the thorium fuel cycle

“…The SULFLEX process is well described in the literature, see Blanco et al (1962) and Finney and Hannaford (1961). The main principle is to selectively dissolve the cladding in a threefold stoichiometric amount of 4-6 M H 2 SO 4 .…”

“…It has been shown (Blanco et al, 1962) that the unwanted dissolution of the actual fuel during the cladding dissolution was very small. Generally, less that 0.3 % of the uranium and less than 0.2 % of the thorium was lost during the process.…”

“…The DAREX decladding method is more thoroughly described by Blanco et al (1962) and Ferris and Kibbey (1960). The main principle involved is to dissolve the steel cladding in a boiling mixture of 5 M HNO 3 and 2 M HCl.…”

Aqueous Processing of Thorium Fuels. Part Ii

“…An increased residence time wi II be requi"red to dissolve this fuel. Since both irradiated and unirradiated fragmented fuel (8-20 mesh) was >99% dissolved in 5 hr in batch tests 1 These are: burning in oxygen followed by dissolution of the Th02-U309 ash in boiling 13 ~ HN03--0.04 ~ F, or fine grinding, probably to 200 mesh to ensure rupture of all the fuel particles, followed by acid leaching to recover the uranium and thorium.…”