Droplet Adhesion for Breaking Oil-In-Water Emulsion and Phase Separation

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Droplet Adhesion for Breaking an Oil-in-Water Emulsion and Phase Separation

Princeton Docket # 14-2952


Present microfluidic technologies to break emulsions or to separate phases in the emulsions include electric-field enhanced coalescence, passive-controlled coalescence, and a phase separator with embedded porous membrane. Researchers in the Department of Mechanical and Aerospace Engineering at Princeton University have developed a novel, simple and reliable method to break stable oil-in-water emulsions.

The invention describes a device to break stable oil-in-water emulsions and separate the oil phase from the aqueous phase. The device is simply made of straight glass capillaries, which are commercially available with different dimensions. The breaking of the emulsion in the device is realized by controlled adhesion of the droplet on the inner surface of the capillary, which depends on the translation speed of the droplets, instead of the help of an external electric field. There is a critical speed below which the adhesion of droplets occurs. After the stable oil-in-water emulsion flows out of the device, the dispersed oil phase separates from the continuous aqueous phase, and appears as a continuous oil phase on top of the aqueous phase. The device can be used as a phase separator for recycling of emulsions in droplet microfluidics or in the application of liquid-liquid extraction based on emulsions.


Can be used as:

·         A phase separator for recycling of emulsions


·         A separator downstream to microfluidic liquid-liquid extraction devices based on emulsions


      ·         Device is simple and inexpensive


·         No external electrical field is required


Faculty Inventor

Howard Stone is the Donald R. Dixon '69 and Elizabeth W. Dixon Professor in Mechanical and Aerospace Engineering at Princeton University.  His research has been concerned with a variety of fundamental problems in fluid motions dominated by viscosity, so-called low Reynolds number flows, and has frequently featured a combination of theory, computer simulation and modeling, and experiments to provide a quantitative understanding of the flow phenomenon under investigation.  Prof. Stone is the recipient of the most prestigious fluid mechanics prize, the Batchelor Prize 2008, for the best research in fluid mechanics in the last ten years.  He is also part of the Class of 2011 inductees of the American Academy of Arts and Sciences and is a member of the National Academy of Engineering.

Intellectual Property Status

Patent protection is pending.

Princeton is seeking to identify an industry partner for the further development and commercialization of this technology.


Michael R. Tyerech
Princeton University Office of Technology Licensing • (609) 258-6762•

Laurie Bagley
Princeton University Office of Technology Licensing • (609) 258-5579•









Patent Information:
For Information, Contact:
Prabhpreet Gill
Licensing Associate
Princeton University
Howard Stone
Jiang Li
Haosheng Chen
Enkai Dong