DSC Study on the Reaction of Triuranium Octoxide with Hexachloropropene

Abstract

It was known that hexachloropropene (HCP) reacted exothermically with U₃O₈ and produced UCl₅·TCAC (TCAC=trichloroacrylyl chloride), UCl₆·HCP and UCl₄. The peak areas of DSC curves for the reaction were proportional to the amount of U₃O₈, and they were not practically affected by the time of soaking of U₃O₈ in HCP, but affected by the specific surface areas of U₃O₈ and the heat-treatments of UO₃. As the specific surface areas of U₃O₈ decreased, the peak areas of the DSC curves were constant, but the initial temperature (T_i) of the reaction moved to high one and the shapes of the DSC curve became broader. These effect given by the specific surface areas involved also the heat-treatment of UO₃, since specific surface areas influenced greatly by the temperature of the heat-treatment. Difference of crystal structure of starting UO₃ affected the T_i, that is, the lowest T_i temperature obtained for the U₃O₈ prepared from amorphous UO₃. The overall heat of the reaction was estimated to be 569kJ for one mole of U₃O₈.