Three asymmetric hollow fiber polymer membrane systems were studied for application in a membrane-assisted reactor system: (1) a single component polyaramide, (2) a single component polyimide, and (3) a composite polyimide on a polyimide/polyetherimide blend support. The properties of each membrane were tested as a function of temperature. The polyaramide membrane showed good selectivity to hydrogen, but low hydrogen permeance. Both the composite and single component polyimide membranes exhibited much higher hydrogen permeance than the polyaramide with a hydrogen/butane selectivity over 600 at 175{dollar}spcirc{dollar}C for short times.; At long run times, the polyimides showed an aging response. This effect is caused by a densification of the dense, selective skin on the membrane and is characterized by a decrease in permeance and an increase in permselectivity. The rate of decrease in flux, associated with the aging, was temperature dependent and appeared to approach a limiting asymptotic value.; A time-temperature shift factor was calculated from data at two aging temperatures. This shift factor (equal to 0.03 hours) allows the prediction of the effects of aging at any temperature given only one set of aging data.; The polyimide membranes were evaluated for their ability to affect the yield of an n-butane dehydrogenation reactor system. A correctly sized membrane module increased n-butane conversion approximately 12% at a reaction temperature of 482{dollar}spcirc{dollar}C. Neither membrane impacted the catalytic selectivity seen in the reaction-only system.; The stability of the polyimide membranes in the presence of the reaction mixture was evaluated. After accounting for the aging phenomena, the membranes were stable over long run times in the presence of the reactor product stream and any expected impurities.; A simple predictive mathematical computer model of the membrane system was constructed. The model accurately predicted hydrogen removal and hydrocarbon loss through the membrane stage. The model also showed that a large amount of sweep gas is required and that a significant amount (15-25%) permeates into the hydrocarbon-rich stream. This dilution effect acts to enhance conversion, but accounts for only approximately 2% conversion in the second reactor stage.
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