The influence of membrane operating properties on the performance of a membrane-assisted dehydrogenation system has been investigated. The dehydrogenation of n-butane has been used as a test reaction based on its industrial significance. The membrane-assisted dehydrogenation system evaluated consisted of two plug-flow reactors in series with an interstage hydrogen-removal membrane. Highly productive, thermally stable polyimide-ceramic composite membranes were evaluated. The mixed-gas selectivity of the membranes was strongly influenced by the degree of hydrocarbon sorption, which in turn was controlled by the membrane temperature. At temperatures below the critical temperature of butane, the mixed-gas hydrogen/hydrocarbon selectivities of the membranes were below 20. As the temperature increased to above 180-degrees-C, the selectivity increased to above 75. Under these conditions, essentially complete hydrogen removal with less than 2% hydrocarbon losses was achieved. The removal of this amount of hydrogen resulted in an increase in n-butane dehydrogenation of approximately 11% with no decrease in catalytic selectivity.