Thesis: Experimental Study of the Mechanical Behavior of Organoclay-Stabilized Pickering Emulsions

PhD defense: Boutheina MERAD

Title: Experimental Study of the Mechanical Behavior of Organoclay-Stabilized Pickering Emulsions

Team: MécaFlu

Abstract: In the last 2 decades, an increasing interest in emulsions stabilized by solid particles has been observed. Also known as “Pickering”, these emulsions are stabilized through the adsorption of solid particles, with both hydrophobic and hydrophilic characteristics, on the oil/water interface. Depending on the nature, wettability, and surface modification of the used solid particles, the prepared emulsion can be direct (oil in water) or inverse (water in oil). This thesis is an experimental contribution to the study of the rheological and pipe-flow behavior of water-in-oil Pickering emulsions stabilized with organoclay particles. Two main axes were treated in this work: (i) the relationship between the interactions of the solid particles and the mechanical behavior of the emulsions, and (ii) the influence of the dispersed phase concentration on the mechanical behavior of organoclay-stabilized Pickering emulsions. An in-house emulsification system was proposed and the mechanical behavior of the Pickering emulsions was studied using Ultrasonic Pulsed Doppler Velocimetry and local pressure measurements.First, the interactions between the organoclay particles in an organic phase were studied using rheological measurements. Then the Pickering emulsions were prepared and studied using both rheological and pipe-flow measurements. Finally, instability phenomena of the emulsions at high dispersed phase concentration were discussed.

This defense will be held in English and will take place on 19th April 2021 at 10:00am. This defense will take place in the presence of the jury members listed below: