OVERABUNDANCE OF CARBON-MONOXIDE IN CALORIMETRY TESTS

The amount of carbon monoxide recovered from calorimetry tests of high explosives is far larger than the amount predicted by equilibrium cal culations. The present kinetics study of PETN ([(nitro(oxy)methyl]prop anediol dinitrate) has revealed that the cooling of the calorimetry bo mb after detonation of a PETN sample sufficiently slows those reaction s that would otherwise lead to equilibrium so that these reactions are effectively frozen in the time scale of recovery of detonation produc ts. Among these reactions, those that can create CH4 are the most impo rtant ones. Their rates are generally slow at all temperatures relevan t to calorimetry tests. This and the slowing down of a reaction, CO H2O --> H-2 + CO2, at temperatures below 1500 K are the main cause of the freeze-out of CO. A possible slow rate of the soot formation (i.e. , condensed carbon) is not responsible for it. The sensitivity of the present result to the cooling rate of the detonation products and to f ree radicals is also examined.