Micronization of polyethylene glycol by PGSS (Particles from Gas Saturated Solutions)-drying of aqueous solutions

Micronization of polyethylene glycol from aqueous solutions has been successfully performed with a Particles from Gas Saturated Solutions (PGSS)-drying process, producing spherical PEG particles with average particle size of 10 μm and residual water content below 1 wt%. A detailed experimental analysis of the influence of different process and design parameters (temperature, pressure, flow rates, design of the static mixer used to put into contact aqueous solution and CO2) has been carried out. Smaller particles were obtained when carbon dioxide/solution ratio, pressure and temperature were increased. The residual humidity in the product decreased when carbon dioxide/solution ratio and temperature were increased and when pressure was decreased.