DSC/TG and SEM Studies of Synthesized Potassium Sulphamate (PS) and Potassium Dinitramide (KDN) Crystals

Abstract

In the present paper, thermal decomposition and crystal researches of synthesized potassium sulphamate (PS) and potassium dinitramide (KDN) crystals were studied using differential scanning calorimetry/ thermal gravimetry (DSC/TG) and scanning electron microscope (SEM) techniques, respectively. Initially, PS crystals were synthesized using sulphamic acid and potassium hydroxide pellets. Afterwards, PS crystals were used for synthesizing potassium dinitramide (KDN) crystals by the nitration of PS in sulfuric and nitric acid mixture. One sample of PS was used for studying DSC/TG curves, while three samples of KDN crystals were used for the studying DSC/TG curves. The three samples of KDN crystals which were used in the present studies are, a) stored KDN (1 month), b) stored KDN (2 months), and c) washed KDN. All the obtained DSC/TG curves of three KDN crystals are dissimilar to each other, and the probable reasons for this dissimilarity are discussed in the manuscript. For further clarifications, TG curve of KN was compared with the TG curves of three samples of KDN used in the present study. It was observed that, while storage, KDN slowly converts into KN with some rate which gradually changes the physical and chemical properties of KDN.