Porous ceramic membranes: Preparation, transport properties and applications

The preparation and characterization of porous ceramic membranes is present ed. These membranes consist of a macroporous support system, with or withou t a mesoporous intermediate layer, and a microporous top layer. For the mac roporous support membranes two manufacturing routes are described: a conven tional and a RBAO (Reaction Bonded Aluminium Oxide) route. The mesoporous g amma-Al2O3 layer is obtained by means of a sol-gel dipcoating technique. Th ree microporous top layers are considered: SiO2, Al2O3-pillared montmorillo nite and Laponite. These top layers have different pore structures which re sults in different gas transport properties. A SiO2 membrane can be used fo r H-2 removal from a gas mixture. Al2O3-pillared montmorillonite and Laponi te membranes do not show specific gas separation properties. Dehydration of water/2-propanol mixtures by means of pervaporation also proved a differen t behavior for these microporous membranes.