Spherical particle generation by phase change materials: Near monosize particles from emulsions

The solidification behavior of water-in-oil (W/O) emulsion droplets in stagnant pure water was investigated. The droplets were formed from a single capillary tube when the emulsion was pumped by a syringe pump. Different experimental parameters, like surfactant concentration in the preparation of the emulsion, water content in the W/O emulsions, and flow rate, were investigated. The surfactant concentrations were varied from 0.2 to 5 % by volume at different flow rates. The water contents were increased from 5 to 25 % also by volume. The investigation focused on the formation of droplets from a capillary tip. The solidification phenomena of the emulsion drops in the coolant were observed. With higher flow rates, a change from dripping to jetting phenomena was observed. The solid emulsion particles of different sizes were obtained depending on the parameters of the operation. The solid particles were not completely spherical in shape but somewhat ellipsoid.