Synthesis of RDX Catalyzed by Br⊘nsted Acidic Ionic Liquids

The experimental study was carried out on the direct nitrolysis of hexamethylenetetramine (HA) to synthesize hexahydro-1,3,5-trinitro 1,3,5-triazine (RDX) with nitric acid (95%) catalyzed by Br⊘nsted acidic ionic liquids. Various ionic liquids, such as [HMim]X, [(CH2)4SO3HMim]X, and [(CH2)4SO3HPy]X (X− = pTSO−, , CF3COO−), and various parameters, such as equivalents of ionic liquid, mass ratio of nitric acid (95%) to the starting material, and reaction time, were investigated. Ionic liquid [(CH2)4SO3HPyr]NO3 showed good catalytic activity. In the presence of 3.0% mol ratio [(CH2)4SO3HPyr]NO3 ionic liquid to HA, the yield of RDX was improved by 10.5% compared to the system without ionic liquid.