Effects of different milling techniques on the layered double hydroxides final properties

Layered double hydroxides (LDHs) find many applications in the pharmaceutical field. Often, the synthetic product requires a suitable grinding procedure before starting any type of manufacturing process. Choosing the appropriate grinding procedure is important; it must reduce the particle size without modifying the LDH's native layered structure and crystal morphology. Using the LDH MgAI-NO3 as model sample, the aim of this paper was to investigate the influence of three common grinding procedures: knife mill, ball mill and jet mill, on particles size, morphology, specific surface area, crystallinity and flow character. Results highlighted that the jet milling procedure is the most appropriate method to induce particle size reduction while maintaining the original MgAl-NO3 features.