A study on combustion behaviour of carbon-sulphur-sodium nitrate mixtures

Abstract

The effect of substitution of KNO3 by NaNO3 in black powder has been studied by DSC, TG/DTG and FTIR emission spectroscopy. Unlike KNO3, there is no visible exothermic reaction between S and NaNO3, immediately after the melting of NaNO3. Instead a minor exothermic reaction is observed at higher temperature between melted NaNO3 and adsorbed S on carbon. However, there is an increase in such reaction, when carbon black instead of charcoal is used. Infrared spectra show that CO2 and Na2SO4 are major gaseous and solid products respectively. This shows that the combustion of ternary mixtures in air is different from that in N2, with slower heating rate, in DSC or TG apparatus. © 1991 Wiley Heyden Ltd., Chichester and Akadémiai Kiadó, Budapest.