In the crsytallization of cyclotrimethylene trinitramine by drowning out from the acetone/water system, submicrometer-sized particles were successfully produced and polyvinylpyrrolidone (PVP) was found to act as a nucleation promoter and growth retarder. The operating parameters such the spraying distance of solution, solute concentration and temperature were found to influence strongly on the particle size. It was shown that there was an optimum distance due to incomplete atomization and coalescence among fluttered droplets. Aslo, there was an optimum concentration for the formation of submicrometer-sized particles owing to that nucleation and final size of crystals are dependant on the concentration of solution droplets. Lower temperature of solution induces faster nucleation procuces the small-sized particles. However, too low temperature was found to increase in coalescence among atomized droplets inducing agglomeration.
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