Oil-in-water emulsification via cross-junction microchannel at high throughput

Liquid-liquid dispersion process is experimentally investigated to manufacture oil-in-water emulsion working at high flowrates in the cross-slot type of microfluidics. Two types of the cross layouts, namely symmetric and asymmetric configuration, are compared via characterizing the droplet size and size distribution. Because of the higher shear stress and more intensified interaction, the symmetric geometry of the cross-slot is beneficial to produce less amounts of large droplets and dispersing the oil phase more uniformly at the same hydrodynamic conditions, especially in the low range of Re tested in this study. As the flowrates is enhanced, the disparity between them is diminished due to the fact that the instability inside the channel reaches a high level. The detrimental effect of the symmetric configuration is that energy required to burst the dispersed streams is relatively a little higher than with asymmetric one.