Gas/liquid mass transfer phenomena in micellar multiphase systems

Abstract

Micellar multiphase systems are versatile examples for smart solvent systems, which can be applied to intensify important process aspects like reaction rate and product separation. Choosing different temperatures and compositions, the phase behaviour of micellar multiphase systems can be changed, and the reaction conditions altered. Due to the changing phase behaviour, mass transfer is affected, i.e., by altered interfacial areas which can influence the rate of a reaction. Up to two liquid dispersed phases can appear. For fast reactions with a gaseous component, the dispersion conditions and mass transfer are, therefore, complex. In this work, the gas/liquid mass transfer in two and three-phase micellar multiphase systems was observed to gain a better understanding of the transport mechanisms in such systems. The phase behaviour was found to influence the mass transfer strongly. When a microemulsion formed the continuous phase, the mass transfer was enhanced by a factor up to 2.4. Whenever a second liquid phase appeared, the volumetric mass transfer coefficient was decreased. While the mass transfer of the gas to a pure single liquid phase could be predicted by known theory, current mass transfer equations fail to capture the effect in micellar multiphase systems.