TY - CONF A1 - Afraz, N. A1 - Adi, A. A1 - Hecht, Kristin T1 - Gas/liquid mass transport in falling film reactor versus theory N2 - Introduction: Mass transport at gas/liquid interfaces depends on many factors including the gas and liquid properties and hydrodynamics. The mass transport of a gas through the liquid is a limiting step in many chemical reactions. To gain a fundamental understanding of multiphase interfaces, the rate of mass transfer has been measured for pure gases (H2, N2, O2, He) into a thin liquid film with a well-defined surface area and velocity profile. This enables the mass transfer rate to be broken down into one parameter, which is the gas/liquid interfacial area (a), and a second parameter, which is the mass transfer coefficient (kL). Using gases with varying diffusion coefficients enables a comparison of the measured rates of mass transport to the rates predicted by film theory and penetration theory. Method: A gravity-driven thin water film 0.000180 m in thickness flowing along the outer surface of a capillary was contacted with a gas phase inside a closed system. The liquid was circulated continuously until it was saturated with gas and the equilibrium pressure was reached. In this device, there is laminar flow, and therefore, the hydrodynamics of the liquid film are well defined. Results: Penetration theory predicts a non-linear relationship between diffusion coefficient (DAB) and mass transfer coefficient (kL). by means of falling film reactor the actual rates of gas-liquid mass transfer are higher than those predicted by theory. Also, a linear relationship between DAB and kL is observed experimentally. The mass transfer coefficient can even, as a rule of thumb, be assumed to be relatively constant with a value of around 10-4 m/s for aqueous solutions. T2 - 13th European Congress of Chemical Engineering (ECCE) CY - Online meeting DA - 20.09.2021 KW - Mehrphasenströmung KW - Stofftransport KW - Wasserstoff PY - 2021 AN - OPUS4-53679 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -