Multi-parallel microfluidic recrystallization and characterization of explosives

A multi-parallel recrystallization system based on microfluidic technology was established for rapid recrystallization-condition screening and small-batch preparation of high-quality explosives. The system employs a T-shaped tree chip and four parallel oscillating flow microreactors to scale up the microfluidic system and to realize multi-channel explosive preparation. Explosive 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) was used to study the ability of the multi-parallel recrystallization system in the screening of recrystallization conditions including solvent types, the ratio of anti-solvent flow rate to solvent flow rate, and surfactant types. Results show that the system can effectively screen the preparation conditions of LLM-105 and simultaneously prepare 2,2′,4,4′,6,6′-hexanitrostilbene (HNS), 1,3,5-trinitroperhydro-1,3,5-triazine (RDX), and octahydro-1,3,5,7-tetranitro-1,3,5,7-tetrazocine (HMX) with high-quality crystal morphology.