Ceramic Microchannel Heat Exchanger and Reactor for SOFC Applications

In this paper, we present the design, fabrication, and performance of novel ceramic microchannel reactors in heat-exchanger and fuel-reforming applications. Reactor design is based on the results of computational fluid mechanics simulations so that uniform fluid flow and thermal gradients are observed across the reactor body. Reactors are fabricated by CoorsTek, Inc. as four-layer Pressure Laminated Integrated Structures using 94% Al2O3 materials. The cost-effective PLIS fabrication produces a single ceramic body with internal microchannels and manifolding. High-temperature performance of the ceramic microchannel reactor is measured through non-reactive heat-exchanger experiments. After coating rhodium catalyst materials over two of the four reactor layers, use of the ceramic microchannel reactor in fuel-processing applications is demonstrated through catalytic partial oxidation of butanol. While significant syngas formation is demonstrated, further work is necessary to improve reforming conditions, increase the selectivity to hydrogen and carbon monoxide, and integrate the microchannel reactor with a tail-gas combustor.