Preparation and characterization of alumina-coated silicon carbide supports

Porous ceramic membranes have attracted research interest because of their high thermal and chemical stabilities. Recently, silicon carbide membranes have been fabricated. However, insufficient data exist regarding the microfiltration applications of silicon carbide supports. We compared the measured membrane properties of alumina-coated silicon carbide and pyrophyllite supports. The experimental data were used to determine whether the average pore size of a silicon carbide support could be effectively reduced while maintaining acceptable water permeability by controlling the thickness of the alumina coating via a multiple dip-coating method. The membrane properties of the alumina-coated silicon carbide supports were examined using scanning electron microscopy, mercury porosimetry, and a dead-end microfiltration system.