Development of Advanced Continuous Flow Recrystallization Processes for Energetic Nitramines

The focus of the Phase 1 work is to provide a thorough and complete evaluation of several competing technologies and methodologies for the continuous recrystallization of the energetic materials 1,3,5-trinitrohexahydro-1,3,5-triazine (RDX) and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX). Technologies for consideration include mixed suspension mixed product removal (MSMPR) which may consist of a cascade of continuous stirred tank reactors (CSTR) or oscillatory baffled reactors (OBR). Continuous flow recrystallization will be evaluated using an oscillatory flow reactor (OFR) in the form of NiTech’s continuous oscillatory baffled reactor/crystallizer (COBR/C). The feasibility of using each of these technologies for continuous crystallization of RDX and HMX will be evaluated, with initial studies evaluating each platform for its ability to reliably produce a narrow particle size distribution and its capability to tailor resulting particle size. This approach will ensure the continuous crystallization space is expansively covered, giving the best possible opportunity for success. The most promising continuous crystallization platform and methodology will then be down-selected and further characterized via an optimized design of experiments (DoE) under the Phase 1 Option. This will identify process parameters which influence mean particle size and determine the most optimal conditions to crystallize specific sizes of RDX and HMX. The ultimate goal is to develop a continuous flow recrystallization process that can produce α-RDX and β-HMX in the desired crystal morphology, with a narrow particle size distribution, and a tailorable particle size. The tailorable particle size will allow the input of different crystallization process parameters which result in a desired particle size of RDX and HMX. This will provide the ability to meet different size classes of RDX and HMX, as well as any desired specialized without the requirement to sieve or mill the recrystallized material.