Synthesis of mesoporous alumina-titania membranes by the sol-gel method

Ceramic tubular membranes with alumina-titania top layers were prepared using the dipping procedure and a mixed sol composed of both boehmite and titania. The influence of the Ti/Al ratio, the amount of an organic additive (namely hydroxypropylcellulose), the dip-time, the number of depositions and drying-calcination conditions on the membrane morphology and transport properties were investigated. The conditions for the formation of a defect-free and homogeneous top layer were individuated.