Numerical Investigation of a Novel Grinding Device for the One-Pot Production of Ferromagnetic Nanoparticles

Featured Application: The proposed procedure allows for the simple, efficient, and sustainable production of magnetic nanoparticles, which can be readily used in one-pot purification processes. The use of nanoparticles (NPs) in industrial applications is consistently increasing given their peculiar properties compared to bulk precursor materials. As a result, there is a growing need to develop alternative technical strategies for the synthesis of such NPs using processes that are not only environmentally friendly but also easy and inexpensive to implement on an industrial scale. In this regard, a novel approach has recently been proposed for the safe and sustainable production of metal NPs directly from a bulky solid by magnetically driven low-energy wet milling, which overcomes the limits of applicability to ferromagnetic materials through a unique device configuration. In the present contribution, the understanding of this alternative configuration is deepened by computational investigation. Discrete Element Method (DEM) simulations were used to model the dynamics of the system, highlighting the role of the various parameters involved in the setup and operation of the process. The collisions between grinding and primary particles are analyzed in terms of frequency, impact angle, and energy. Comparing the results with the standard device configuration, the general trend is preserved, though collisions at higher impact angle and energy are also detected.