The basic features of the propane dehydrogenation reaction in a combined membrane reactor with a hydrogen-permeable palladium module and chromia-alumina catalyst (9.0 wt % Cr) in the temperature range of 520-580A degrees C have been studied. Under optimum conditions (T, 550A degrees C; propane space velocity and a stripping gas flow rate of 600-900 h(-1) and 100-250 cm(3)/min, respectively), the feedstock conversion to propylene increases by a factor of 1.6-2.0. It has been suggested that compliance between the rate of H-2 formation and its withdrawal through the membrane is of considerable importance.