Effect of alpha-radiolysis on TRUEX-NPH solvent

An unexpectedly high degradation of the TRUEX (TRansUranic EXtraction) solvent occurred during the treatment of waste solutions from the New Brunswick Laboratory. The waste solutions treated contained approximately I g/L of Pu-239 and 20 mg/L of Am-241. Earlier studies of a-radiolysis using carbon tetrachloride rather than normal paraffinic hydrocarbons (NPH) as a diluent indicated greater resistance to radiation damage than observed, For this study, the TRUEX-NPH solvent was loaded with Am-241 in nitric acid, irradiated with doses up to 3.5 Mrad, and monitored for decline in extraction capability as a function of absorbed dose. Results of this study are being used to improve the Generic TRUEX Model, a thermodynamic model that permits flow-sheet design for solvent extraction processing.