Ceramic membrane elaboration using supercritical fluid

Macroporous alumina supports were prepared from commercial delta-Al2O3 and modified by hydrolytic decomposition of titanium isopropoxide in supercriti cal propan-2-ol. Various experimental parameters were studied in relation t o the deposition of TiO2 particles on the substrate surface and inside the pores: temperature, precursor concentration, water-to-alkoxide ratio, solut ion flow rate, and deposition time. A set of these parameters was found to allow supported membranes with high nitrogen permeation (9.5 X 10(-6) mol.m (-2).s(-1).Pa-1) and low average pore radius (1.5 nm) to be obtained. (C) 2 000 Elsevier Science Ltd.