Analytical Sciences

Development of a Microfluidic Device for Measurement of Distribution Behavior between Supercritical Carbon Dioxide and Water

Akira OHASHI,*,** Masahiro SUGAYA,* and Haeng-Boo KIM*,**

*College of Science, Ibaraki University, Mito, Ibaraki 310-8512, Japan
**Frontier Research Center of Applied Atomic Sciences, Ibaraki University, Tokai, Ibaraki 319-1106, Japan

A measuring method for the distribution behavior between supercritical carbon dioxide and water by a microchip was developed. A surface modification of the microchannel by dichlorodimethylsilane induced a spontaneous phase separation of the supercritical carbon dioxide and aqueous phases in the microchip. The maximum contact time of the aqueous phase to the supercritical carbon dioxide phase was obtained as 0.58 s. This device withstood pressure up to 12.8 MPa. The distribution of tris(acetylacetonato)cobalt(III) (Co(acac)₃) from the supercritical carbon dioxide phase to the aqueous phase in a microchannel could be measured. The concentration of Co(acac)₃ distributed into the aqueous phase was increased by lengthening the contact time of both phases. These demonstrations showed that the method developed in this study could be used to measure the distribution behavior between supercritical carbon dioxide and water.

J-STAGE: View this article in J-STAGE