Porous titanium oxide membranes with pore sizes in the range of 2.5-22 nm were prepared by a sol-gel procedure, and were applied for decomposition of methanol and ethanol as model volatile organic compounds (VOCs) in a photocatalytic membrane reactor, where oxidation reaction occurs both on the surface and inside the porous TiO2 membrane while reactants are permeating via one-pass flow. Methanol was completely photo-oxidized by black-light irradiation to CO2 when methanol at a concentration of 100ppm was used at a feed flow rate of 500 x 10(-6) m(3)/min, but the conversion decreased when the MeOH concentration in the feed was increased. Pt-modification was carried out by photo-deposition, and led to a decrease in pore diameter. Using Pt-modified membranes, a nearly complete oxidation of methanol up to 10,000 ppm at a feed flow rate of 500 x 10-6 m(3)/min was observed. Thus, such membranes would be effective for purifying a permeate stream after one-pass permeation through the TiO2 membranes. The decomposition of ethanol is also discussed. (c) 2006 Elsevier B.V. All rights reserved.