Characterization of Potassium Nitrate/Dextrose Solid Rocket Propellant Using Calorimetry

Abstract

The use of the Potassium Nitrate as an oxidizer in solid rocket propellants has been common in recent years for experimental research in solid rocket propulsion systems. This chemical is used as a compound of black powder and explosives, but in the last 30 years, it has been studied for applications in semiprofessional rocket propellant, implemented by Universities in research and academic projects. The Potassium Nitrate/Dextrose propellant is also known as Candy propellant and presents some advantages compared with other solid propellants. They are low production costs and ease of acquisition for the chemical components. These advantages are attractive for low-cost projects, compared to the low performance; this does not discourage its use.The Candy propellant presented a lack of experimental data to characterize, for example, its thermal properties. For this reason, were used the Differential Scanning Calorimetry and the Semi-Micro Calorimetry tests, to obtain the heat of combustion, power, and temperatures of melting and ignition. The grains of Candy propellant were manufactured at the University of Conception by the Propulsion Interest Team. This is the first time which is reported the calorimetric data of the Candy propellant (Potassium Nitrate/Dextrose). The results in this work presented a heat combustion in the range 523 -567 Cal•g −1 , decomposition temperature in the range 356 -361 °C and a heat released in the range 1080 -1809 J•g −1 of the mixture KNO3/Dextrose, which contribute to the professional characterization of the propellant.