Multiphase surfactant-assisted reaction-separation system in a microchannel reactor

Abstract

The Lewis acid-catalyzed addition of trimethylsilyl cyanide to p-chlorobenzaldehyde in a microchannel reactor was investigated. The microchannel was integrated to promote both reaction and separation of the biphase system. FeF₃ and Cu(triflate)₂ were used as water-stable Lewis acid catalysts. Sodium dodecyl sulfate was incorporated in the organic-aqueous system to enhance the reactivity and to manipulate the multiphase flow inside the microchannel. It was found that the dynamics and the kinetics of the multiphase reaction were affected by the new micellar system. Parallel multiphase flow inside the microchannel was obtained, allowing for continuous and acceptable phase separation. Enhanced selectivity was achieved by operating at lower conversion values.

Keywords

Lewis acid catalysis / multiphase reactions / process intensification / microchannel reactor / green engineering

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Acknowledgements

Mr. Hajime Itoh from Nagoya University is highly acknowledged for his valuable technical assistance and advice.

Nomenclature

Ca　 Capillary number, –

μ　 The viscosity of the continuous phase, Pa•s

U　 The flow velocity, m•s^–1

σ　 The interfacial tension, N•m^–1

RIGHTS & PERMISSIONS

2014 Higher Education Press and Springer-Verlag Berlin Heidelberg