Synthesis and energetic content of red oil

‘Red oil’ materials, resembling those produced during destructive incidents at Hanford and Savannah River, have been prepared following prolonged heating of uranyl nitrate, nitric acid, tributylphosphate (TBP) and a hydrocarbon diluent either under reflux conditions or within a high-pressure bomb reactor. Phase inversions, a characteristic feature of ‘red oil’ formation, were observed only when a cyclic hydrocarbon diluent was employed and were not observed when a straight chain hydrocarbon was used. The energetic content of the ‘red oil’ materials was found to be in the range from 30 to 444 J g−1 (7.2–106.1 cal g−1) as determined by DSC in open pans in the temperature range 20–350°C, with a typical value being 200 J g−1 (47.8 cal g−1). A ‘baseline’ Purex solution of UO2(NO3)2(TBP)2 released 120 J g−1 (28.7 cal g−1) upon heating through the same temperature range.