This study demonstrates that thermally stable palladium membranes can be electrolessly plated on ZrO2 modified planar porous stainless steel (PSS) with EDTA-free bath following a palmitic acid treatment. Prior to elctrroless plating of palladium with EDTA-free bath, the bottom of the ceramic-modified planar porous stainless steel (PSS) was shielded by a palmitic acid prior to palladium plating to prevent the diffusion of the plating solution through the bottom of the substrate that causes palladium plating in the pores of the PSS. The hydrogen permeation flux and the nitrogen leakage were monitored for an extended period of time at a pressure difference of 100 kPa and 873 K and showed that the palmitic acid-treatment provided membrane stability at high-temperature. (C) 2014 Elsevier B.V. All rights reserved.