Thermal decomposition of decanol phase modifiers during reprocessing applications

The separation of minor actinides from high-level liquid waste can be carried out by solvent extraction. To avoid third phase formation, PUREX extractants such as tri-n-butylphosphate (TBP), dihexyloctanamide (DHOA) were judiciously chosen as phase modifiers, since the feed for minor actinide partitioning is a reject solution obtained after PUREX process. In the recent past, n-decanol (nD) and iso-decanol (iD) are proposed as phase modifiers. However, the hazards of using these alcohols in reprocessing are unknown. It should be noted that the aqueous feeds for minor actinide partitioning is composed of 3-4M HNO₃ a strong oxidizing agent. The nitric acid solution in contact with the organic phase containing metal-solvate is likely to facilitate the oxidation of organics that are susceptible to oxidative degradation Thermal decomposition behavior of nD and iD in the presence and absence of nitric acid is presented in this paper