The catalytic decomposition of potassium perchlorate

Ignition of Nanoscale Titanium/Potassium Perchlorate Pyrotechnic Powder: Reaction Mechanism Study

“…The Arrhenius plot of oxygen release for the simulant mixture in Figure gives a corresponding activation energy, shown in Table , which is ∼55 kJ/mol smaller than the activation energy for pure KClO 4 oxygen release, and roughly consistent with the ∼42 kJ/mol drop in oxygen release activation energy found by Collins et al. under slower heating conditions . Catalysis of oxygen release reconciles the previous findings, which suggested that ignition occurs before the oxygen release from the oxidizer.…”

“…In the case of the two ignition environments analyzed thus far, the ignition temperatures all occur at least 50 K below the oxygen release temperature of the pure oxidizer for a given heating rate. This finding suggests that either the reaction mechanism is dominated by a purely condensed phase reaction before the temperature of oxygen release in KClO 4 or the release of oxygen is catalyzed by interactions not yet considered. ,,,, …”

“…The results from this analysis shown in Figure clearly illustrate a catalytic behavior of TiO 2 , where the melting and oxygen decomposition temperature of KClO 4 shift to lower temperatures as the weight percentage of TiO 2 increases. This behavior has been investigated previously by repeated studies conducted several years ago, which characterized and modeled the catalytic behavior as one that is electronic in nature and related to the semiconductor properties of TiO 2 . ,, …”

“…This behavior has been investigated previously by repeated studies conducted several years ago, which characterized and modeled the catalytic behavior as one that is electronic in nature and related to the semiconductor properties of TiO 2 . 22,27,32 Based on active titanium content and stoichiometry of a typical mixture of TKP, it was estimated that the weight percentage contributed by the oxide layer is roughly 15 wt %. This equates to a TiO 2 content of roughly 20 wt % when mixed only with KClO 4 .…”

Periodates as Potential Replacements for Perchlorates in Pyrotechnic Compositions

“…Also important for formulators interested in burning rates, enhancing the rate of decomposition of the periodates through the use of additives has proved challenging. Additivess uch as TiO 2 and MnO 2 have been shown to catalyze the decomposition of KClO 4 [30,35].I nterestingly,M uraleedharan and co-workers showed that these additives had am inimal effect on the thermald ecomposition kinetics of KIO 4 [33].H owever,d ue to the generally lower decomposition temperatures of the periodates, compositions containing these oxidizers may exhibit correspondingly lower ignition temperatures.…”