Abstract
Pd/(CexZr(1−x)O2)/MCM-41 catalysts containing variable loadings of Ce and Zr with fixed molar ratio Ce/Zr = 1/2 are prepared by impregnation. Synthesized MCM-41, Pd(acac)2, Ce(NO3)3.6H2O and Zr(acac)4 are used as chemicals. The effect of Ce and Zr contents on the textural, structural and catalytic properties of the prepared catalyst is studied. N2-physisorption, H2-chimisorption, XRD, TEM-EDX and TPR are the main techniques used to characterize these catalysts. The obtained results show that Ce and Zr addition impacts differently the surface area, porosity and particle sizes of the Pd/(CexZr(1−x)O2)/MCM-41 catalysts, depending on the variable amount of Ce and Zr. A huge enhancement in the methane combustion activity is obtained. Catalyst with 5 wt% of Zr shows better catalytic performance in methane combustion with T50 and T100 (temperature of 50% and 100% of conversion, respectively) equal to 360 and 500 °C, respectively.
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•Pd/CexZr(1−x)O2@MCM-41 catalysts were prepared by impregnation.•The addition of Ce and Zr significantly enhances the catalytic activity for methane combustion.•The effect of Ce and Zr loading is studied.•Catalytic activity is affected by the PdO reducibility and metallic particles size.•Catalyst with low Ce and Zr content (5% wt) exhibits the best activity.