Abstract
Catalytic oxidation is the most efficient method of minimizing the emissions of harmful pollutants and greenhouse gases. In this study, ZrO
2
-supported Pd catalysts are investigated for the catalytic oxidation of methane and ethylene. Pd/Y
2
O
3
-stabilized ZrO
2
(Pd/YSZ) catalysts show attractive catalytic activity for methane and ethylene oxidation. The ZrO
2
support containing up to 8 mol% Y
2
O
3
improves the water resistance and hydrothermal stability of the catalyst. All catalysts are characterized by X-ray diffraction (XRD), Brunauer–Emmett–Teller (BET), O
2
-temperature-programmed desorption (O
2
-TPD), and CO-chemisorption techniques. It shows that high Pd dispersion and Pd–PdO reciprocation on the Pd/YSZ catalyst results in relatively high stability.
In situ
diffuse reflectance infrared Fourier-transform (DRIFT) experiments are performed to study the reaction over the surface of the catalyst. Compared with bimetallic catalysts (Pd : Pt), the same amounts of Pd and Pt supported on ZrO
2
and Y
2
O
3
-stabilized ZrO
2
catalysts show enhanced activity for methane and ethylene oxidation, respectively. A mixed hydrocarbon feed, containing methane and ethylene, lowers the CH
4
light-off temperature by approximately 80 °C. This shows that ethylene addition has a promotional effect on the light-off temperature of methane.