Research of the combustion of gas-generating compositions with additives of carbon powders

Abstract

Carbon materials obtained from secondary plant raw materials are widely used in various industries, where they are applied as catalysts, adsorbents and in pyrotechnics for creating gas-forming systems. In this work, activated carbon of two types– obtained from the walnut shell and as a product of utilization of gas adsorbents was used. The combustion of a three-component mixture of sodium nitrate, magnesium, and carbon obtained by carbonization of a walnut shell or by grinding gas mask elements was studied. It was found that at a low carbon content, the combustion of the mixture occurs at a high rate in a convective mode. As the working composition, a mixture with a component ratio of 60% – NaNO3, 20% – Mg, 20% – C was chosen, which is characterized by rather high values of gas productivity. The burning rate of a composition based on carbon from walnut is about two times higher than in the case of carbon from a gas mask, and the flame temperature is higher by about 500 K. X-ray phase analysis of solid combustion products showed that the main products are magnesium oxide and sodium carbonate. The presence of a partially unreacted initial oxidant of sodium nitrate has also been found, and its content in combustion products of a carbon-based incendiary composition from a gas mask is higher than in the case of combustion of a mixture based on carbon obtained from a walnut shell. This can probably be explained by the fact that gaseous products are released during combustion, and this leads to partial dispersion of the initial components in the combustion wave, which is more pronounced when using carbon obtained from a gas mask. As a result of the research the prospect of using such a mixture in gas generator cartridges is shown.