SEPARATION OF ALCOHOL WATER MIXTURES BY PERVAPORATION THROUGH ZEOLITE-A MEMBRANES/

Zeolite NaA membranes were prepared from homogeneous solution on macro porous zirconia composite supports in sheet and tube form. Zeolite KA membranes were obtained by ion exchange from the sodium form. The memb ranes were tested for the removal of water from isopropanol/water mixt ures by pervaporation. Feed and permeate compositions and flux were me asured for pervaporation at 25 and 70 degrees C. Both the Na and K for ms of zeolite A membranes were highly selective, separation factors in excess of 10(4) being achieved at low concentrations of water in the feed. Membrane performance was not affected by heat treatments to 150 degrees C. (C) 1997 Elsevier Science B.V.