Efficient and Safe Chemical Gas Generators with Nanocomposite Reactive Materials

Abstract

Abstract : This report summarizes the major results obtained in the studies of gas-generating compositions involving novel nanocomposite and mechanically alloyed reactive materials, produced by arrested reactive milling. An experimental setup that allows laser ignition, high-speed and infrared video recording, and mass spectrometric analysis of evolved gases has been designed and constructed. The experiments have shown that mechanically alloyed Al/Mg powder is a promising alternative to iron and tin in oxygen-generating compositions as significantly smaller amounts of this additive are needed for a steady propagation of the combustion wave and respective steady oxygen generation. A novel approach to hydrogen release from ammonia borane has been developed that involves the reaction of mechanically alloyed AlMg powder with water as a source of heat for ammonia borane thermolysis and hydrolysis. This reaction also releases hydrogen from water, thus increasing the total hydrogen yield. The investigation of iodine-generating compositions was focused on thermite mixtures based on mechanically alloyed AlI2 powder. The experiments have shown that mixtures of this powder with CuO, MoO3, Bi2O3, and I2O5 exhibit a self-sustained propagation of the combustion front with similar burn rates. Iodine pentoxide burns better with mechanically alloyed AlI2powder than with micron-sized Al powder.