An original method is proposed in this work to regulate the alkane/O-2 ratio in catalytic membrane reactors for oxidative reactions. The concept is based on the use of a "chemical valve membrane" as O-2 distributor. V2O5 is an attractive key constituent for such a membrane because of its reversible red/ox behavior (V2O5/V2O3) and related textural variations able to regulate membrane permeance. This work shows how membrane permeability can be controlled by the red/ox characteristics of the gas phase. We studied the influence of the reducing gas on the evolution of membrane permeance in relation to the membrane weight changes, up to 500 degreesC. The red/ox kinetics have been compared using a series of reducing gases (i-C4H10, C3H8, C2H6, C2H4, CH4 and H-2). Finally, we showed how the permeability of such a membrane, when used as an O-2 distributor in a reactor configuration, is controlled by the red/ox characteristics of the gas phase (i.e. by the alkane/O-2 ratio in the reactor).