Fabrication of novel porous Al2O3 substrates by combining emulsion templating and gel-tape-casting methods

Abstract Scalable fabrication of membrane substrates, having high strength, customizable pore size, high gas and water permeation, has been key issue in recent years due to the rapid growth of engineered separation processes. This work provides a novel fabrication method for porous Al2O3 membrane substrates (PAS) by using suspension emulsions as pore forming agents and gel-tape-casting as a shaping method. The substrates displayed a smooth surface and a porous internal structure. By adjusting the volume ratio of water and oil from 1:1 to 1:4, the average pore size increased from 0.53 to 1.06 μm. Moreover, the porosity increased from 50.7% to 75.8%, in contrast, the bending strength decreased from 46.7 ± 1.5 to 17.3 ± 1.1 MPa. In addition, the permeability of the N2 and water was improved from 8.13 × 105 to 5.10 × 106 L m−2 h−1 bar−1 and 5.02 × 103 to 1.84 × 104 L m−2 h−1 bar−1 respectively and as a result, this can qualify the membranes for a wide range of applications.