An evaporation-induced self-assembly method was employed for the first time to prepare Ni-Al-oxide/Ni-foam composites as support for a novel Ru/Ni-Al-oxide/Ni-foam 3D composite catalyst, which was utilized to effectively deep-remove CO in hydrogen-rich gas for fuel cell applications. The characterizations of BET, XRD, SEM and TEM show that a mesoporous Ni-Al oxide was constructed on Ni foam via this feasible way with specific surface area as high as 42 m(2) g(-1), which assured a uniform dispersion of Ru nano-particles. The resultant monolithic catalysts exhibit an excellent performance for CO selective methanation, which may be attributed to its unique high specific surface area for more active sites and high thermal conductivity for avoiding the formation of local hot spots. The CO outlet concentration in hydrogen-rich gas can be decreased down to as low as less than 10 ppm from a high level of 1 vol% in a wide working temperature range of 180-280 degrees C, while the CH4 outlet concentration is less than 2 vol%. (C) 2016 Elsevier B.V. All rights reserved.