An Electrochemical Impedance Spectroscopic Diagnostic Device for Characterization of Liquid-Liquid Systems and Phase Separation Detection in Emulsions

• Author / Creator

  Shahidi, Seyedehsan

• Rapid characterization of complex fluids, especially sensing emulsion stability, is crucial for many industrial applications, ranging from pharmaceutical industry to petroleum production. Electrochemical impedance spectroscopy (EIS) is a powerful tool for electrical characterization of such systems. In this study, a "milli-fluidic" EIS test fixture which is inexpensive, easily fabricated, yet robust, is designed and fabricated using 3D printing technology, which allows reliable experiments, and can then be disposed of after each test. The developed cell is tested using solutions, liquid-liquid mixtures, and oil-water emulsions. Frequency response analysis and equivalent circuit modeling have been performed to find the effective electrical properties of the liquids, and relate them to their physical properties, such as stability. EIS is applied to reveal the electrical behavior of emulsions during phase separation. It is found that creaming can be sensed based on permittivity decay, and capacitance-based measurements can be utilized to detect phase separation in emulsions.

• Subjects / Keywords

  • Milli-fluidic
  • Electrochemical
  • Impedance
  • Multicomponent
  • Stability
  • Separations
  • Emulsions
  • Spectroscopy
  • Dielectric
  • Phase

• Graduation date

  Fall 2013

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R36Q4G

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.