Effect of Short Reducing Pulses on the Dynamic Structure, Activity, and Stability of Pd/Al₂O₃ for Wet Lean Methane Oxidation

Natural gas is a suitable alternative to gasoline and diesel fuels decrease the carbon footprint of mobility energy sectors. Unburnt CH4 typically removed from exhaust using palladium-based catalysts, which suffer thermal deactivation as well water sulfur poisoning. In this work, activity Pd/Al2O3 in wet lean oxidation was enhanced by applying repeated short reducing pulses (SRP) leading significant drop apparent activation compared static operation. The degraded after aging also recovered same approach. Fit time-resolved operando XAS data kinetic models revealed that only moderately active PdO exists under operation, while during SRP operation highly PdOx species are formed maintained presence metallic Pd. On basis combined spectroscopic data, we propose practical range Pd degree (25–65% content) preserve high conversion.