Extraction liquide-liquide dans des gouttes à l'échelle microfluidique

Abstract

The goal of this work is to build a new tool dedicated to the comprehension of mass transfers at microscopic scale. The tool relies on “digital micro fluidics” - a technology where everything is done in droplets that swiftly circulate in Microchips. At this scale, transfers phenomena are different from a drop at macroscopic scale because of the presence of flows with low Reynolds number. Liquid-liquid extraction systems were qualitatively and quantitatively studied : aqueous droplets were generated in rectangular micro channels with geometry flow-focusing (200µm wide and 30 to 90 µm high) in a flow of octan-1-ol. Two cases were studied: the dispersed phase or the continuous phase played alternatively the role of extracting and quantitative measurement of intensity in droplet was achieved by fluorescence techniques.