Study the operating conditions on agglomeration of RDX particles in anti-solvent crystallization by using statistical optimization

Abstract

The unfavorable growth and agglomeration of micro-particles of RDX explosive was almost observed in manufacture process. For preventing of growth of micro-particles and agglomeration in anti-solvent crystallization process, the effect of additives glucose, sucrose and poly ethylene glycol-2000 and wetting solvent of isopropyl alcohol were studied. Taguchi experimental design was used for optimization of the operating conditions. The type of additive, the amount of additive (%wt.), solvent of wetting and wetting time were selected for optimization of the conditions. By using 4 factor and 3 levels, 27 experiments were conducted (L27). Results showed that in the presence of 2 %wt. of sucrose additive and isopropyl alcohol solvent, the agglomerations of particles were decreased so that a decrease 30–50% in the average of particles size was seen. Addition additives were effective in storage container and for reduce the agglomeration of particles during storage. Also, the agglomeration rate of particles was reduced over time at optimized conditions. Imaging optical microscopy, scanning electron microscopy (SEM), and particle size analyzer (PSA) methods were used for particles size analyzing as a response in statistical optimization and quality control of the final product. The sensitivity to some mechanical and shock stimuli on the RDX in presence of sucrose additive was tested and the obtained results showed the insignificant effect of additive on the safety properties of pure RDX. Keywords: RDX explosive, Taguchi experimental design, Agglomeration, Additive, Anti-solvent