Thermal hazard assessment of tris(2-methyl butyl) phosphate: A comparison with tri-n-butyl phosphate and tri-n-amyl phosphate

Abstract

The thermal decomposition behaviour of tris(2-methyl butyl) phosphate (T2MBP), a higher branched homologue of tri-n-butyl phosphate (TBP), which possesses the vital characteristics of a potential extractant for the processing of nuclear materials is the subject of the present work. The thermal stability of neat T2MBP and 1.1 M T2MBP/n-dodecane (in the presence and absence of HNO3) has been determined using adiabatic calorimeter. The results have been compared with the corresponding tri-n-amyl phosphate (TAP) and TBP based systems. From the calorimetric experiments, the thermo-kinetic parameters have been deduced and the resulting end products have been analysed. The data show lower magnitude of exothermicity for T2MBP compared to TAP based systems. The present work thereby highlights the influence of alkyl group chain length and branching on the thermal decomposition behaviour of trialkyl phophates, which in turn will help to identify an alternate to TBP to avoid the potential runaway explosion hazards.