A novel method to prepare mesoporous MgAl₂O₄ coating on the honeycomb cordierite ceramics from only inorganic salt and alkali by the generalized Lewis acid-base theory was reported. The Pt-based monolithic catalysts were prepared successfully after Ce_xZr_1-xO₂ modified and Pt loaded by in-situ acid-alkali reaction. The samples were characterized by scanning electron microscope (SEM), X-ray diffraction (XRD), and N2-sorption. The results showed that the coating had uniform microcrystal structure as well as high surface area (>250 m²穏^-1) and large pore volume (0.32 cm³穏^-1). The investigations of H₂ catalytic combustion showed these monolithic catalysts could fastly start up even at room temperature, and H₂ initial conversion could reach more than 95%.

Key words: hydrogen catalytic combustion, monolithic catalyst, acid-alkali theory, porous MgAl₂O₄, ceria-zirconia solid solution