Revealing the Catalytic Role of Sn Dopant in CO2-Oxidative Dehydrogenation of Propane over Pt/Sn-CeO2 Catalyst

CO2-oxidative dehydrogenation of propane (CO2-ODHP) provides a promising route for propylene production. Sufficient propane conversion and propylene selectivity remain a great challenge due to the difficulty in activating inert propane and CO2 simultaneously. Herein, a Sn doped CeO2 supported Pt (Pt/Sn-CeO2) catalyst in CO2-ODHP reaction is reported. Sn doping appears to kill two birds with one stone for propane and CO2 activation. On the one side, it increases the electron density of Pt species via PtSn alloy formation, promoting propane adsorption and C-H bond cleavage. On the other side, it enhances oxygen vacancy concentrations of CeO2 support, facilitating CO2 dissociation. A higher propylene selectivity (63.9 % vs 22.3 %) was obtained on 0.1 wt % Pt/1.0 wt % Sn-CeO2 than that on 0.1 wt % Pt/CeO2 with a comparable propane conversion (15.1 % vs 14.3 %) at 550 degrees C after 240 min on stream. This work provides a reference for designing efficient catalysts.

Automated summary

This study reports the application of a Sn-doped catalyst in CO2 oxidative dehydrogenation of propane. By forming PtSn alloy and increasing oxygen vacancy concentration in CeO2 support, propane conversion and propylene selectivity are improved.