Abstract
Inorganic membranes have many advantages for dehydration of azeotropic mixtures of ethanol and water for renewable fuel purposes. In this work, we developed an inorganic membrane from γ-alumina and tested it for its ability to selectively permeate water over ethanol. Ethanol adsorbed both chemically and physically on the surface of γ-alumina, blocking the 47 Å pores sufficiently to enhance water selectivity. Stable flux was observed over 6 h, but after 4–5 h of continuous testing, water selectivity rose above 200 due to this blocking phenomenon.