A Hydrothermally Stable Irreducible Oxide-Modified Pd/MgAl(2)O(4)Catalyst for Methane Combustion

Abstract

Catalytic combustion is promising in removing trace amounts of CH(4)to address serious environmental concerns. Supported Pd-based catalysts are most effective but often suffer from low stability in applications owing to the water-vapor-induced sintering. Herein, we develop a universal strategy to prepare irreducible-oxide-modified Pd/MgAl(2)O(4)catalysts which show high activity and excellent stability against both hydrothemal aging at elevated temperatures and deactivation in long-term reaction under wet conditions. The addition of irreducible oxides inhibited the deep oxidation of Pd in the oxygen-rich conditions, which preserved not only the epitaxial structure but also a suitable active phase of Pd-PdO(x)on MgAl2O4, thus promoting both activity and stability. This work provides new insights into the effect of metal-oxide interaction on CH(4)combustion and offers an avenue to design hydrothermally stable and active combustion catalysts for industrial applications.