(95c) Membrane Micro Reactors for Heterogeneously Catalyzed Gas-Liquid Reactions

A current trend in the field of micro reactor engineering is the integration of multiple unit operations in a single device, such as pretreatment of raw materials, mixing, reaction and separation. We will present different micro reactors with integrated membrane functionality. These polymeric micro reactors are fabricated by CNC milling and clamping of commercial membranes. In this research project, we are mainly interested in applications based on gas-liquid contacting. Hydrophobic membranes are applied to create a stable interface, where the liquid cannot wet the porosity. By using multiple gas-liquid contacting points with different types of gasses or vapors, local differences in chemical composition can be realized in the micro reactor. The opportunities of this concept will be discussed into detail and we will give a proof-of-principle by generating local pH gradients. Then we will focus on heterogeneously catalyzed glucose oxidation. For this application, a Pt catalyst is immobilized on the membrane and oxygen is supplied from the gas phase. Analysis of the product stream is performed on-line by Electro Spray Ionization Mass Spectroscopy (ESI-MS). The tested micro reactor is shown in Figure 1. We will describe the fabrication procedure of the device and show first results, ending with a general outlook on the applicability of our concept.