Energetic Material Synthesis: Scale-up Using a Novel Modular Microflow Reactor Setup

The advantages of microflow reactors have proven to be manifold, e.g., the excellent cooling ability, which allows performing exothermic reactions like nitrations safely. A critical point remains the transition from gram scale to industrial production. On an industrial scale, they are often designed for specific syntheses and are therefore less useful for a conventional research laboratory. A reactor setup was successfully developed mitigating these shortcomings and allowing the use of highly corrosive materials, like fuming inorganic acids (e.g., nitric, sulfuric acid), bases (e.g., bleach solutions), and chlorinated solvents. As a proof of functionality, the synthesis of nitroguanidine has been performed on a lab scale and was significantly improved over reported batch syntheses in terms of safety and production rate. A scale-up to industrial scale has hence become feasible.