Emulsion Formation using corona discharge and electrohydrodynamic pumping


Project ID: D2020-22


Making water-in-oil emulsions often requires high pressure, ultrasonication, or sensitive inversion techniques that may still only result in a semi-stable colloid. In addition to emulsion shelf life, these techniques have drawbacks, such as having high-energy consumption and narrow/sensitive production parameters, needing batch production processes, and being equipment intensive. Therefore, there is a need for a more efficient process to produce emulsions.

Invention Description

Researchers at the University of Toledo have developed a system to create an emulsion using corona discharge and electrohydrodynamic pumping. Corona discharge is a voltage discharge that occurs between two electrodes and can be seen as a blue/purple glow. It can create an ionic wind that strips away electrons from air molecules and induce OH- groups on surfaces, making them easily wettable with water. In the UToledo system, oil is poured into a continuous flow channel that contains a pair of electrodes and a water droplet source. The resulting high electric voltage discharge and ionic winds carry and submerge water droplets into the oil phase forming an emulsion.


  • Making macro- micro-, nano- water-in-oil emulsions
  • Example emulsions: Silicone oil, or any oil with similar electrical conductivity?
  • Emulsions are used in cosmetics, drug delivery, food products, oil and gas, materials processing, pharmaceuticals, soil remediation, cleaning products


  • Less energy consumption
  • Less dependent on viscosities
  • Scalable; Continuous processing possible
  • Contactless
  • No need for external pumping, precise temperature control, or pressure
  • Uniform emulsions
  • Increased stability

IP Status:                     Patent pending

Publication:                Sojoudi et al. A Contactless Method for Electrocoalescence of Water in Oil. ACS Omega 2021, 6, 14298-14308.

Patent Information:
For Information, Contact:
Katherine Pollard
Licensing Associate
The University of Toledo
Hossein Sojoudi
Mohcen Shahbaznezhad
Amir Dehghanghadikolaei
corona discharge
ionic wind