Ni catalyst on mixed support of CeO2–ZrO2 and Al2O3: Effect of composition of CeO2–ZrO2 solid solution on the methane steam reforming reaction

In this study, catalysts containing 5 wt.% Ni deposited on a support composed of a CeO2–ZrO2 solid solution deposited on alumina were tested in the steam reforming of methane. The supports, with various ratios of Ce to Zr, were prepared by co-precipitation of the oxide precursors, followed by calcination in synthetic air. The catalysts were then prepared by Ni impregnation of the supports. The prepared solids were characterized by temperature-programmed reduction with H2 (TPR‐H2), in situ X-ray diffraction (XRD) and X-ray absorption near-edge structure (XANES) spectroscopy. The XRD analysis confirmed the formation of a solid solution between ZrO2 and CeO2. In the catalytic tests, it was found that catalysts with higher Ce content did not exhibit deactivation during 6 h of reaction. The catalyst with highest Ce content, Ni(0.8Ce0.2Zr)Al, provided the best result, with the highest rate of conversion of methane and the lowest carbon deposition, which may be partly due to the smaller Ni0 crystallites in this sample and also the segregated CeO2 particles may have favored H2O adsorption which could lead to higher C gasification.

XPD for samples supported on Al(CeZr).Figure optionsDownload as PowerPoint slideHighlights
► Ni catalysts supported on CeO2–ZrO2–Al2O3 were prepared and tested in the SRM.
► The formation of solid solution between ZrO2 and CeO2 was identified by XRD.
► Ni(0.8Ce0.2Zr)Al, provided higher rate of CH4 conversion and lower C deposition.
► This sample presented lower Ni0 crystallite size and the CeO2 segregated.
► These properties may have favored H2O adsorption and C gasification.