Properties and microstructures of porous alumina for support carrier of separation membrane.

Abstract

Porous alumina is used as support carrier of separation membrane materials. In an actual application, it is exposed in high thermal stress condition. Thermal shock fracture test was performed on porous alumina ceramics, which have various porosities and pore sizes. Fracture strength, fracture toughness, Young modulus, thermal expansion coefficient and thermal conductivity, which affect to the thermal shock property, were also estimated. All properties except for thermal expansion coefficient and thermal shock strength tend to be decreased with the increase in porosity and pore size. On the other hand, the nitrogen permeability was increased with the increase in porosity and pore size. Properties of porous alumina with well-growth grain necking were higher than that of smaller pore size at the same porosity.