Ceramic Plate Heat Exchanger for Heterogeneous Gas Phase Reactions

摘要

A catalytic active ceramic plate heat exchanger reactor has been developed for application in microtechnology. The principle advantages of microreactors in industrial process applications have been cited in numerous publications, a good overview is given in [1]. The ceramic plate heat exchanger coated with catalyst represents a specialized microreactor construction offering a large surface to volume ratio an improved temperature control and excellent catalytic adhesion. The ceramic plate heat exchanger is intended to be a cheap alternative to existing microreactor technology. The starting material for realizing the microreactor is a slip made from a particular form of α- alumina, which is tape casted by the doctor blade process. The green ceramic tapes are fashioned into the internal structure desired by laser techniques, stacked and laminated with other layers of green tapes. Microreactors with one reaction compartment and two adjacent cooling/ heating chambers comprising seven layers have been prepared. After sintering the microreactors are externally glazed to prevent leakage. The final geometry selected was optimized by fluid-mechanical simulations. The excellent harmonization of catalytic activity, diffusive mass transport and heat removal is the primary advantage of the ceramic catalytic plate heat exchanger for heterogeneous catalytic gas phase reactions. The gas phase reaction can be operated over a wide temperature range and the volume specific reactor performance increased. The catalytic active ceramic plate heat exchanger has considerable potential for microreactor applications involving heterogeneously catalyzed gas phase reaction, since it requires little or no modification of existing catalyst recipes.