Fabrication of a Continuous Alumina Fiber-Reinforced Mullite Composite Filter

Abstract

Continuous Al2O3 fiber reinforced mullite composites are candidates for use as hot gas particulate filters in advanced coal-based power generation systems such as PFBC and IGCC. the composite was fabricated by dipping fiber cloth fabric into a slurry, which was prepared with mullite powders and precursor solution synthesized from Si and Al alkoxides. the filtration layer, which consisted of mullite grains, reacted little with fly ash even at 1373K. Because the mullite, which acts as the protective layer, did not form properly on the Al2O3 fibers using the alkoxide method, the ash adhered to the fibers in the supporting layer. However, the use of the alkoxides increased the ultimate flexure strength of the composite, which showed excellent filtration performance for fly ash at room temperature.