Monolithic ceramics and heterogeneous catalysts: Honeycombs and foams

Recent advances have been made in research on ceramic monolithic catalyst supports, particularly on honeycombs and ceramic foams. In the case of honeycombs, cordierite is the most commonly applied composition, but alternative materials, such as SIC, are beginning to be used for demanding conditions. Typical catalytic applications of honeycombs include use as catalyst supports for the removal of gaseous or particulate emissions from combustion engines (gasoline and diesel), and for reducing nitrogen oxide emissions from power plants. Ceramic foams are used commercially for the filtration of molten metals, and are attracting increasing attention as catalyst supports due to high thermal stability, high porosity and increased tortuosity with respect to honeycombs.