Support-mediated alkane activation over Pt-SO₄/Al₂O₃ catalysts

Sulphate-promoted alkane combustion has been investigated over a series of Pt/Al₂O₃ catalysts using pre-sulphated alumina supports. Catalyst sulphation greatly enhanced ethane combustion over Pt/Al₂O₃, and also improved methane and propane light-off performance. Catalyst activity increased with Pt loading, however the magnitude of sulphate promotion was independent of Pt loading under oxidising conditions, but scaled with alkane chain length. Propane combustion activity was directly proportional to the surface coverage of aluminium sulphate sites; support-mediated alkane activation is the dominant process in sulphate promotion.