Current technologies and future trendsin ammonium nitrate

Ammonium nitrate (AN) with chemical formula NH4NO3 is one of themost commonly important ammonium and nitrate compounds, andextensively produced via acid-base reaction. AN is an inexpensive, safe,easily available crystalline salt, which has exhibited colorless,hygroscopic, detonable, and low burning rate properties. However, itsuffers from two drawbacks involving phase transformation orpolymorphic transition near ambient temperature, and poor flowability forthe transport, storage, package, and handling processes.AN is widely applied in the area of agricultural nitrogen fertilizerbecause of its acutely toxicity to palmate newts or other amphibians. Atthe same time, it has also been used as energetic materials, such as anoxidizer in rocket propellant formulations, gas generator, and a majorcomponent mainly in industrial explosives. Several methods related tophase modification or stabilization of AN have been studied by additionof potassium salts, metal oxides, and co-crystallization with crown etherto avoid phase transition in ambient temperature. To prevent caking of AN and enhance flowability of it, spheroidization was employed for the applications.