Palladium-supported catalysts in methane combustion: comparison of alumina and zirconia supports

Abstract

Recebido em 4/8/11; aceito em 6/2/12; publicado na web em 15/5/12Palladium catalysts supported on alumina and zirconia were prepared by the impregnation method and calcined at 600 and 1000 °C. Catalysts were characterized by BET measurements, XRD, XPS, O 2 -TPD and tested in methane combustion through temperature programmed surface reaction. Alumina supported catalysts were slightly more active than zirconia supported catalysts, but after initial heat treatment at 1000 °C, zirconia supported palladium catalyst showed better performance above 500 °C A pattern between temperature interval stability of PdOx species and activity was observed, where better PdOx stability was associated with more active catalysts.