Design and Fabrication of Microreactors for High Temperature Applications

126 p.Thesis (Ph.D.)--University of Illinois at Urbana-Champaign, 2007.Microreactors show promise because of the phenomenon of higher heat and mass transfer rates as the length scale decreases. This thesis describes the fabrication and characterization of SiC and SiCN inverted beaded catalyst supports, which have high chemical and thermal stability (are stable to 1200°C in air), are highly porous (have a void fraction of 0.74) to reduce the pressure drop across the reactor, and have a high surface area-to-volume ratio. Because these catalyst supports are monolithic, they also eliminate the channeling that typically occurs with packed particles. This thesis then describes the integration of SiC catalyst supports with alumina housings and the characterization of these integrated reactors for the decomposition of ammonia to form hydrogen. Different approaches to generate hydrogen, including the steam reforming of hydrocarbons and the decomposition of NH3, are also evaluated on the basis of the energy density and availability of the fuel, the size of the reactor, the complexity of the fuel processing system, and heat transfer.U of I OnlyRestricted to the U of I community idenfinitely during batch ingest of legacy ETD