Deactivation of the scandium concentrate recovered from uranium leach liquors

摘要

The article deals with deactivation of a scandium concentrate recovered as a by-product from uranium leach liquors. It was shown that gross activity of the primary scandium concentrate was (1.8 +/- A 0.25) x 10(8) Bq kg(-1). Alpha and beta activity of the concentrate was conditioned mainly by Th-230 and the radioactive chain Th-234-Pa-234m-Pa-234 respectively; significantly lower activity of Th-227 was also found. Extraction system containing 5 wt% of di(2-ethylhexyl)orthophosphoric acid and 10 wt% of tributyl phosphate in Shelsol D70 diluent was suggested for scandium deactivation. It was shown that five stages of extraction using the suggested extraction system provided decontamination factor as high as 7 x 10(4).