Patent ID: 7655277

Claim:
A method of preparing a titania composite membrane for separating water/alcohol mixtures, the method comprising the steps of: (a) modifying macropores of a porous support by sequentially treating the macropores with silica xerogel and γ-alumina sol in this order; (b) forming a titania surface layer according to a sol-gel process by coating said modified porous surface with titania sol; and (c) drying said membrane at 20-30° C. and relative humidity of 50-70% followed by calcining said membrane at 250-400° C. wherein said membrane has a pore size of 1-2 nm, a surface area of 300-350 m 2 /g, a permeagility for water of 25-520 g/m 2 -h and a selectivity for water of 1-400 in water/alcohol mixtures at 250° C.