AIR SEPARATION BY HIGH TEMPERATURE ZEOLITE MEMBRANES

THE COLLECTION AND STORAGE OF OXYGEN-ENRICHED AIR ABOARD AIRBREATHING PROPULSION VEHICLES IS NECESSARY TO DEVELOP FULLY REUSABLE ORBITAL LAUNCH SYSTEMS. THE PRESENT AIR COLLECTION AND ENRICHMENT SYSTEM (ACES) DESIGN INVOLVES A HEAT EXCHANGER AND A CRYOGENIC ROTARY AIR SEPARATOR. SUBSTANTIAL IMPROVEMENTS HAVE TO BE MADE TO THE ACES TO REDUCE ITS WEIGHT AND MAKE IT SUITABLE FOR FLIGHT APPLICATIONS. THE PROPOSED PROGRAM INVOLVES THE DEVELOPMENT OF A HIGH TEMPERATURE MEMBRANE CONSISTING OF MOLECULAR SIEVE ZEOLITES UNIFORMLY DISPERSED IN AN INORGANIC BINDER MATRIX. THE COMPOSITE MEMBRANE WILL OPERATE AT THE INLET AIR STAGNATION TEMPERATURE AND ELIMINATE THE NEED FOR THE HEAT EXCHANGER. ZEOLITES EMBEDDED WITHIN THE MATRIX OR ON THE SURFACE OF THE MEMBRANE WILL EITHER ADSORB NITROGEN TO THE EXCLUSION OF OXYGEN OR VICE VERSA. THE COMPOSITE MEMBRANE SYSTEM CAN BE OPERATED AT HIGH AIR HANDLING RATES AT A LOWERED SYSTEM WEIGHT. THE OBJECTIVE OF THE PHASE I PROGRAM WOULD BE TO DETERMINE THE FEASIBILITY OF THE HIGH TEMPERATURE INORGANIC MEMBRANE SYSTEM BY FABRICATING FLAT SHEET MEMBRANES AND CHARACTERIZING THEM WITH RESPECT TO THEIR ADSORPTIVE CAPACITY AND PERMEABILITY.