Properties of Surfactant-Modified Ammonium Nitrate

Porous ammonium nitrate is frequently used for specific applications due to its porous structure when compared with conventional ammonium nitrate, however, its higher transportation costs increase overall operational expenses. This study investigated the preparation of porous granular modified ammonium nitrate using ionic surfactant PST as an additive via spray granulation. The effects of varying PST concentrations (0−0.4%) on the pore structure, oil absorption capacity, thermal stability, and explosive properties of ammonium nitrate were examined. The research results indicate that increasing PST content gradually transforms dense ammonium nitrate particles into a porous structure with distinct interconnected pores. Thermal stability remains essentially unchanged, and the matrix chemical composition undergoes no fundamental alteration, though its adsorbed water content decreases. The modified samples exhibit enhanced binding capacity with the oil phase. The detonation velocity of the assembled charge increases from “failed to detonate normally” in the unmodified state to 2831.85 m/s. Trace amounts of PST can induce the formation of a porous structure in ammonium nitrate without significantly compromising thermal safety, while markedly improving detonation velocity performance, demonstrating potential for engineering applications.