GAS SEPARATION MEMBRANES HAVE RECENTLY BEEN COMMER- CIALIZED AND ARE BEING USED INDUSTRIALLY FOR THE RECOVERY OF HYDROGEN, FOR ENRICHED AIR PRODUCTION, FOR ENRICHED NITROGEN PRODUCTION, AND FOR ACID-GAS REMOVAL AMONG OTHER APPLICATIONS.

GAS SEPARATION MEMBRANES HAVE RECENTLY BEEN COMMER- CIALIZED AND ARE BEING USED INDUSTRIALLY FOR THE RECOVERY OF HYDROGEN, FOR ENRICHED AIR PRODUCTION, FOR ENRICHED NITROGEN PRODUCTION, AND FOR ACID-GAS REMOVAL AMONG OTHER APPLICATIONS. MEMBRANE PROCESSES HAVE THE POTENTIAL FOR GREATLY REDUCING ENERGY REQUIREMENTS FOR INDUSTRIAL SEPARATIONS. THE PRINCIPAL BARRIER TO WIDER USE OF GAS SEPARATION MEMBRANES IS THE DIFFICULTY IN MAKING SUFFICIENTLY SELECTIVE MEMBRANES WITH AN ECONOMICALLY HIGH ENOUGH GAS FLUX. BECAUSE STAGING MEMBRANE MODULES (WHICH WOULD ENABLE OPERATION WITH LOW-SELECTIVITY, HIGH-FLUX MEMBRANES) HAVE NOT PROVED ECONOMICAL, MEMBRANES ARE MADE OF HIGH-SELECTIVITY, LOW-PERMEABILITY POLYMERS FORMED INTO VERY THIN LAYERS OF INCREASED GAS TRANSPORT RATES. WITH CURRENT, ANISOTROPIC MEMBRANE TECHNOLOGY, MEMBRANES WITH BARRIER LAYERS ABOUT 0.1MM CAN BE MADE. FURTHER IMPROVEMENTS IN PERFORMANCE OF GAS SEPARATION MEMBRANES DEPEND ON DEVELOPING TECHNOLOGIES TO MAKE EVEN THINNER, MORE SELECTIVE MEMBRANES. IMPROVED MEMBRANES FOR HYDROGEN SEPARATION ARE VERY IMPORTANT BECAUSE OF THE INCREASINGLY IMPORTANT ROLE FORESEEN FOR HYDROGEN IN SYNFUELS PROCESSING, IN CHEMICAL PRODUCTION FROM SYNTHESIS GAS, IN AMMONIA PRODUCTION, AND IN BOTTOM- OF-THE-BARREL UPGRADING. A NEW APPROACH TO MAKING GAS SEPARATION MEMBRANES FOR HYDROGEN RECOVERY IS PLANNED, WHICH COUPLES THE PROVEN CAPABILITY OF GLOW DISCHARGE POLYMERIZATION TO DEPOSIT FLAWLESS, THIN COATINGS WITH A NOVEL SUBSTRATE. THIS SHOULD SUBSTANTIALLY IMPROVE BOTH MEMBRANE HYDROGEN FLUX AND SELECTIVITY OVER PRESENT MODULES AND MAY MAKE TWO-STAGE MEMBRANE MODULE OPERATION ECONOMICALLY FEASIBLE, BROADENING THE APPLI- CATION OF MEMBRANES TO HIGHER PURITY HYDROGEN PROCESSING REQUIREMENTS.