ok, as far I understand, this is a batch process like on pharmacy. what's important to know, is that temperatures must be equal or bellow negative 5.º degrees, and the ultrasonic spray dry at 45 Khz. the rdx must be solved with an anti solvent like ethanol acetone , that's the only chemical where rdx (cyclotrimethylenetrinitramine or 1,3,5-trinitro-1,3,5-triazacyclohexane) is soluble.

   Preparation and Characterization of Ultrafine RDX.pdf by Elsa Cristina David on Scribd