Continuous microfluidic process for formation of ADN-Prills

Ammonium dinitramide (ADN) has the potential to substitute ammonium perchlorate (AP) as oxidizer in solid propellants, which would avoid the environmental, safety and health issues that AP causes. For the incorporation in a propellant matrix spherical shapes of ADN are necessary. The continuous producing of spherical ADN (ADN-prills) in microfluidic droplet generators offers the benefit of controlling the size and the size distribution of the prills. To show the feasibility of the process, a proper experimental setup was developed. Different droplet generators were tested and the most suitable was chosen. The influence of flow velocity of the continuous and disperse phase and the concentration of surfactants on the droplet size were investigated.