Recovery of Pu from the AHWR fuel fabrication scrap

摘要

During the fabrication of the fuel material for the Advanced Heavy Water Reactor (AHWR) employing (Th, Pu)O_2, significant volume of scrap is expected to be generated. A method was developed to recover Pu from the waste employing di(2-ethylhexyl) isobutyramide (D2EHIBA) in n-dodecane as an extractant under varying concentrations of nitric acid, Th and the extractant. In view of the selective extraction of hexavalent, metal ions over tetravalent metal ions with D2EHIBA, Pu was adjusted to Pu(VI) in the present work. AgO was identified as suitable oxidant. D2EHIBA concentration was optimised as 1.25M for the preferential separation of Pu(VI) over Th (200g/L) (Table 1).