Preparation of Water-In-Oil Emulsions Using Hydrophobic Microporous Hollow Fibers

The preparation of fine and monodispersed water-in-oil (w/o) emulsions by utilizing hydrophobic polypropylene hollow fibers with 0.4 µm pores was investigated in this work. The experiments have been carried out using demineralized water as the disperse phase, mineral oil Velocite 3 as the continuous phase, and polyglycerol polyricinoleate (PGPR 90) in the concentration range of 2.5-10 wt% as the oil-soluble emulsifier. The size of water droplets in the resulting emulsions and the droplet size distribution strongly depended on the disperse phase content, the transmembrane pressure difference and the emulsifier concentration. The stable emulsions with a very narrow droplet size distribution and the mean droplet size lower than 0.27 μm were produced using 10 wt% PGPR 90 at the pressure difference below 30 kPa.