DMI-9505382 Bai The objective of this Small Business Innovation Research Phase II project is to develop and demonstrate zeolite based inorganic membrane modules that carry out gas separations using a molecular sieving mechanism. In Phase I, TDA Research Inc. (TDA) developed the techniques necessary to grow dense continuous films of ZSM-5. ZSM-5 films were successfully grown on single crystal silica and alumina substrates. The films were approximately 100 Am thick and remained bonded to the substrate even when thermally cycled. ZSM-5 films were then grown on porous silica discs. Before calcination, the films were found to be gas tight. Following calcination, permeation measurements were carried out using Ar, N2, i-C4H,o, and SF6 as the test gases. The membranes were adherent, defect free, and the permeance data and calculated separation factors were consistent with a molecular sieving mechanism. In the Phase II project, TDA will develop techniques to coat Membralox alumina monoliths in order to develop efficient cost effective inorganic gas separation membranes. In order to improve the gas separation properties of the membranes, the pore sizes will be optimized using chemical means. Nineteen channel Membralox alumina modules will be modified with ZSM-5 and mordenite films, the pore sizes optimized for selected gas separations, and the performance of the module will be evaluated. Zeolite membranes have high separation ratios, extremely high fluxes, and can operate in high temperature and aggressive chemical environments that would destroy polymeric membranes. Therefore, zeolite modified alumina membranes will find their first applications in gas separations under aggressive conditions. Other potential high value applications include use as solid electrolytes in advanced bakeries, as selective films in chemical sensors, and in advanced optical and electronic devices.
