γ-Al2O3 sheet-stabilized isolate Co2+ for catalytic propane dehydrogenation

Co-based catalysts are promising alternatives to replace Pt- and Cr-based catalysts for propane dehydrogenation (PDH) in view of the catalytic activity for C-H bond activation, low cost, and low toxicity. However, the reduction of unstable CoOx species and coke deposition cause serious catalyst deactivation. In this work, a sheet-shaped Co-Al2O3 catalyst comprising of isolate Co2+ sites shows a high intrinsic activity (specific reaction rate > 16 mmol g(-1) h(-1)) and catalytic stability in highly selective PDH reaction (>97% C3H6 selectivity). Extensive characterization demonstrates that the tetrahedral Co2+ isolated site is stabilized by the gamma-Al2O3 matrix, facilitating propylene desorption to inhibit formation of coke and other byproducts and to free the active Co sites. (C) 2019 Elsevier Inc. All rights reserved.