Oxide support mediated [FeO4] domains steering C–H activation in propane dehydrogenation

Supported iron-based catalysts have emerged as promising candidates for alkane dehydrogenation due to their excellent sulfide resistance, cost-effectiveness, and environmental advantages to meet the needs of industrial applications. However, the practical application of iron-based catalysts is hindered by insufficient catalytic activity and rapid deactivation, primarily caused by the reduction/sintering of metastable iron species and concomitant carbon deposition during the reaction. This work systematically investigates the divergent catalytic behaviors of alumina- versus silica-supported Fe catalysts in propane dehydrogenation (PDH). Comprehensive characterizations demonstrate that the surface acidic alumina support establishes strong metal-support interactions (MSI) with electron-rich [Fe 2.4+ O 4 ] domains, effectively enhancing catalytic activity with a propane conversion of 29 % and 80 % propylene selectivity, outperforming silica-supported counterparts. At the same time, the robust active structure of [Fe 2.4+ O 4 ] in the 3Fe/Al 2 O 3 catalyst matches good regeneration capability, enabling suffered from six reaction-regeneration cycles. Moreover, this study indicates that effective propane dehydrogenation requiring synergistic interplay between FeO x speciation and acid sites on the support surface.