Experimental Investigation of the Performance and Catalytic Properties of xFe2O3/ZrO2 Mesoporous Catalysts in Propane Dehydrogenation in the Presence of CO2

In this work, the performance of a series of ZrO2-supported Fe2O3 mesoporous catalysts (xFe2O3/ZrO2) was investigated with different weight percentages of Fe in the propane dehydrogenation process with CO2. The results showed that the synthesized catalysts suffered from coke deposits and bulk Fe2O3 formation at low and high Fe loadings, respectively. An optimum Fe loading of 12 wt % indicated the best results due to the better reduction properties: an initial propane conversion of 32% and a propylene selectivity of 73%. Active oxygens on active Fe3+ species and Zr4+ strong acid sites were found to be responsible for propylene production and the source of side reactions, respectively. Increasing the iron species on ZrO2 improved the propylene selectivity and catalyst stability, which were related to the coverage of Zr4+ strong acid sites. The results showed that the presence of CO2 led to the high stability of the catalyst through the reoxidation of active Fe3O4 species and coke removal.