The catalytic effect of rare earth oxides on the thermal decomposition of ammonium perchlorate

Abstract

The kinetics of the decomposition of ammonium perchlorate (AP) in the presence of rare earth oxides, yttrium oxide (Y2Oa) and lanthanum oxide (La2Oa) as catalysts have been investigated. The Prout-Tompkins and contracting-cube equations have been found to fit the isothermal thermogravimetry data of eatalysed AP decomposition. Gases evolved during catalytic decomposition of AP were analysed by infrared spectroscopy by matrix isolation technique. The mechanism of the catfflysed thermal decomposition of AP has also been disseussed in terms of an electron transfer process.Ammonium perchlorate (AP) has been found to play a key role in the combustion of composite solid propellants. The thermal decomposition of AP has been studied over an usually wide range of temperature [1]. Ammonium perchlorate is stable at room temperature but decomposes to a measurable extent at temperature exceeding 150 ~ It has also been observed that the decomposition and burning properties of AP can largely be improved by using various catalysts [2,3]. As a result chromium oxide, zinc oxide, copper oxide, copper chromite etc., find use in propellants. The effect of catalysts on the combustion of composite propellants has also been dealt with by many authors [4,5]. Solymosi has reviewed the effect of different oxides and salts on the slow and fast decomposition of AP [2]. The Prout-Tompkins, Avrami-Erofeyev and the contracting-cube equations have been found to fit the data. Furthermore, kinetic parameters for the catalytic AP decomposition in the acceleratory as well as deceleratory periods have also been reported b~, some workers [6,7].We have studied the kinetics of the thermal decomposition of AP in the presence and absence of catalysts. Rare earth oxides, yttrium oxide (Y 203) and lanthanum oxide (La~O3) were used as catalysts. The Prout-Tompkins and contracting-cube (n ~ 3) equatiOns were found to fit the TG data for the catalysed thermal decomposition of AP. Also, an attempt is made to identify the gases evolved at different terriperatures during the decomposition in the presence and absence of catalysts by inl~rarrd spectroscopy.

Kinetic Decomposition Models for Ammonium Percholorate Hybrid Catalyzed with Nanothermite Particles

“…Ammonium perchlorate (AP) is the most common oxidizer used in various energetic systems [1]. It's widely accepted that thermal decomposition kinetics play a vital role in its combustion behavior [2]. The thermal decomposition of AP is a complex process that is affected by different conditions such as shape, crystalline phase, and crystal purity [3][4][5][6][7].…”

Preparation and Application of La2O3 and CuO Nano Particles as Catalysts for Ammonium Perchlorate Thermal Decomposition

“…Moreover, the thermo kinetics of thermal decomposition for the modified AP samples (with La 2 O 3 and CuO nanocatalysts) were explored by the use of DSC data. Literature review showed that La 2 O 3 have been used as a catalyst to characterize its effect on thermal decomposition of AP [29], while there are a few reports about the effect of CuO NPs prepared by ball milling route on the thermal behavior of AP [30].…”

Effects of Aluminum Nanoparticles on Thermal Decomposition of Ammonium Perchlorate

“…1 The thermal decomposition characteristics of AP play a key role in the combustion behavior of composite solid propellants and are sensitive to the presence of additives, which are used to improve the performance of the propellants. 2 The most commonly used additives are metal oxides 2−10 and metal powders.…”