ZSM-5, MCM-41 and SiO2-Al2O3 composite membranes were prepared and characterized. In such an order the influence of the chemical composition and powder properties on the permeability and the surface acidity of the composite membranes were investigated. Inorganic powders have been characterized by XRD, IR-spectroscopy, nitrogen adsorption -desorption and potentiometric titration. The permeability of the membranes has been tested, in the catalytic reactor conditions, using a Wicke-Kallenbach cell. The results shown the variation of the gas (O-2, H-2, CH4) and liquid (H2O, C6H12) permeability with porosity of the inorganic powders and composition of the membranes.