A core-shell structured, metal-ceramic composite-supported Ru catalyst for methane steam reforming

Methane steam reforming on a metal ceramic composite-supported ruthenium catalyst is studied at high temperatures. The core-shell structured Al2O3@Al composite consisting primarily of an Al metal core with a high surface area gamma-Al2O3 overlayer is obtained by hydrothermal oxidation. Under the synthesis condition, primary Al2O3@Al particles aggregate to form a hierarchal secondary structure with macrosize inter-pores. This core-shell composite support enhances the heat conductivity and provides a high surface area for fine dispersion of a catalytic Ru component on the gamma-Al2O3 overlayer. The Ru/Al2O3@Al catalyst exhibits significantly higher CH4 conversion than the conventional Ru/Al2O3 catalyst, indicating its superior properties for methane steam reforming at high temperatures contributed due to the fine Ru dispersion and facilitated heat and mass transfer via the unique catalyst structure. This metal-ceramic composite catalyst is stable in the reforming reaction for an extended time, suggesting reasonable stability in its physicochemical properties. (C) 2012 Elsevier B.V. All rights reserved.