(241d) Porous Microreactors for Gas-Liquid Contacting

The concept for exploiting porous layers (membranes) within microstructured reactors is investigated. A porous structure can be utilized for several functions, including gas-liquid contacting. For this, the porous layer needs to be non-wetting for the liquid phase in order to reduce mass transport limitations. During contacting, the gas phase can diffuse easily through the porous matrix, while the liquid is contained inside the microfluidic channels. The approach for gas-liquid contacting in microfluidic channels is demonstrated by detecting simple carbon dioxide gas dissolution. By measuring the conductivity of the solution dynamically, mass transport kinetics can be obtained. The experimental results were compared to numerical simulations. This concept is demonstrated for both polymeric as well as ceramic microreactors. Ceramic microreactors can be fabricated by a micromolding method followed by a polymer binder burnout and sinter treatment. The resulting alumina structures are open porous with sub micrometer pore sizes. They can be easily modified by using silane chemistry to obtain the desired surface properties.