TECHNOLOGY FOCUS - INORGANIC CHEMISTRY - Preferred Membrane Structure: The hybrid membrane structure does not comprise the porous inorganic intermediate layers, where the inner channel surfaces of the inorganic porous support comprise a median pore size of less than or equal to 1 micron, and the oxygen-ion conducting ceramic membrane coats the inner channel surfaces of the inorganic porous support. The hybrid membrane structure comprises the porous inorganic intermediate layers, where the oxygen-ion conducting ceramic membrane coats the surface of the porous intermediate layers. The hybrid membrane structure comprises at least two intermediate layers, where the first intermediate layer closest to the inorganic porous support comprises median pore size of 20 nm to 1 micron and the intermediate layer closest to the oxygen-ion conducting ceramic membrane comprises median pore size of less than or equal to 10 nm. Preferred Components: The inorganic porous support is honeycomb monolith or ceramic monolith (preferably cordierite, alpha -alumina, delta -alumina, gamma -alumina, carbon, mullite, aluminum titanate, titania, zirconia, zeolite, metal, silicon carbide, silicon nitride and/or ceria). The inner channels of the inorganic porous support have a hydraulic inside diameter of less than or equal to 3 mm. The inorganic porous support has a porosity of 35-50%. The porous walls of the inorganic porous support comprise a median pore size of 5-15 microns. The porous intermediate layers comprise alpha -alumina, delta -alumina, gamma -alumina, titania, zirconia, silica, cordierite, mullite, aluminum titanate, zeolite, metal and/or ceria (preferably silica and/or zirconia). The intermediate layer has median pore size of 20 nm to 1 micron. The porous intermediate layers have a combined thickness of 20 nm to 100 microns. The oxygen-ion conducting ceramic membrane has a thickness of 5 nm to 0.5 mm. The oxygen-ion conducting ceramic membrane is a pure ionic conducting membrane (preferably doped zirconia and/or doped ceria); or mixed conductive membrane (preferably SrCoO3, SrFeO3, La0.8Sr0.2FeO3- delta and/or BaCe0.15Fe0.05O3- delta ). The monolithic inorganic porous membrane comprises SrCoO3, SrFeO3, La0.8Sr0.2FeO3- delta and/or BaCe0.15Fe0.05O3- delta . In the monolithic inorganic porous membranes, a portion of the channels are plugged at the first end, where the same channels are not plugged at the second end. Preferred Process: The method (M1) involves applying at least one porous inorganic intermediate layer to the inner channel surfaces of the inorganic porous support, where the porous inorganic intermediate layer comprises alpha -alumina; or applying at least two porous inorganic intermediate layers to the inner channel surfaces of the inorganic porous support, where the first inorganic intermediate layer closer to the inorganic porous support comprises alpha -alumina and second inorganic intermediate layer closer to the oxygen-ion conducting ceramic membrane comprises gamma -alumina; and applying the oxygen-ion conducting ceramic membrane by applying a colloidal sol precursor, and drying and firing the precursor to form the oxygen-ion conducting ceramic membrane; or applying the oxygen-ion conducting ceramic membrane by applying a coating slip comprising oxygen-ion conducting ceramic particles, and drying and firing the coating to form the oxygen-ion conducting ceramic membrane. EXAMPLE - A barium nitrate (Ba(NO3)2) (65.3 g), cerium nitrate (Ce(NO3)3.6H2O) (16.3 g) and iron nitrate (Fe(NO3)3.9H2O) (85.8 g) were dissolved in 1:1 volume ratio of water/ethanol (8 l) to obtain clear solution. The solution underwent a flame spray pyrolysis process to obtain a red-brown color powder. The obtained powder contains a nitrate compound. The powder was calcined at 1200 degrees C to provide well crystallized single phase perovskite structure (BaCe0.15Fe0.05O3- delta ). The perovskite powder coated onto a passivated honeycomb channel wall for forming oxygen (O2) permeable membrane.