Novel fabrication processing of porous alumina/mullite membrane supports by combining direct foaming, sol-gel, and tape-casting methods

Abstract Porous alumina/mullite membrane supports (PAMS) were prepared by using direct foaming as pore foaming method, and silica sol-gel, combined with tape-casting, as a shaping method. The supports displayed a smooth surface and a porous internal structure, with spherical pores of 50–200 μm in diameter and interconnecting pores of ∼10 μm in diameter. The supports sintered at 1600 °C exhibited a high bending strength of 13.4 ± 0.7 MPa, an open porosity of 72.8%, and excellent N 2 and water permeation (4.5 × 10 7 and 4.1 × 10 5  Lm -2  h −1  bar −1 , respectively), which qualify them for further consideration in several practical applications.