A microsystem based on micro-capillary jetting for intensifying countercurrent extraction with high phase ratio

Liquid-liquid extraction can be greatly intensified in microchannel devices. Unfortunately, countercurrent flow is hard to realize at microscale. Meanwhile the microdroplet extraction efficiency is still low when the phase ratio is high. Micro-capillary jetting as a new technology for microdispersion can produce microdroplets with narrow size distribution without the restriction of phase ratio. In this work, an integrated microsystem of the micro-capillary jetting for microdroplet generation with the liquid–liquid countercurrent flow in a millimeter column has been developed, and the countercurrent extraction based on microdroplet under high phase ratio was successfully realized. More than 3 theoretical stages within 40 cm were achieved under the phase ratio of 50 ∼ 90 for H 2 O 2 extraction. This paper systematically reports the microdispersion, flow characteristics and extraction performances of the microsystem. It means a lot for future intensification of the countercurrent extraction with high phase ratio.