Binary mixture adsorption of water and ethanol on silicalite

Single component and binary mixture adsorption behaviors of water (H2O) and ethanol (EtOH) were investigated on silicalites with different crystallinity (structure-defects) by a combination of volumetric and gravimetric methods. No influence of the crystallinity of silicalite on the pure EtOH adsorption was observed. On the other hand, the amount of H2O adsorbed on the silicalite with less structure-defects was significantly smaller. The total adsorption amount in the binary mixture adsorption was strongly dependent on the EtOH/H2O ratio in the initial mixture. From the analysis of the binary adsorption data, it became clear that EtOH molecules adsorb preferentially on silicalite with less structure-defects and that more selective adsorption of EtOH takes place under the lower equilibrium pressure.