Dry reforming of methane (DRM) is becoming an appealing research topic because of the urgent need to minimize global warming and the demand for alternative energy resources. However, DRM commercialization and industrial scale application are limited by the deactivation of the applied catalysts. In this work, Ni-based catalysts supported on CeO 2 −MgO mixed oxides (0−20% CeO 2 molar content) were prepared and employed in DRM. The support was synthesized via a coprecipitation method followed by impregnation of Ni metal. The catalysts prepared were characterized by X-ray diffraction, Brunauer−Emmett−Teller (BET) analysis, temperature-programmed reduction, X-ray photoelectron spectroscopy, and field emission scanning electron microscopy (FESEM) techniques. The catalytic performance of the catalysts was evaluated in a fixed-bed continuous reactor with an equimolar (CH 4 /CO 2 ) ratio at 1073 K. The addition of CeO 2 , as a promoter to the support, altered the interaction between Ni and MgO and modulated the properties of the catalysts toward an excellent activity performance and multiwalled carbon nanotubes (MWCNTs) production. CeO 2 significantly enhanced the BET surface area, promoted Ni dispersion, and improved the reducibility of the catalyst. Among the obtained catalysts, Ni/15%CeO 2 −MgO achieved the maximum conversion of both CO 2 (95.2%) and CH 4 (93.7%) without significant deactivation during the reaction. The superior catalytic performance of the aforementioned catalyst is due to the presence of a high quantity of active Ni sites and the high Ce 3+ /Ce 4+ ratio that promoted the formation of oxygen vacancies. With the aid of temperature-programmed oxidation, FESEM, transmission electron microscopy, and Raman spectroscopy analysis, it was found that the amorphous carbon encapsulated the active sites of the catalysts, in the absence of Ce, which suppressed the syngas production significantly. The introduction of Ce not only decreased the deposited carbon but also changed the type of the later to MWCNTs, which had positive effects on the activity of the catalyst.

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Dry reforming of methane (DRM) is emerging as an enticing research area due to the crucial requirement to mitigate global environmental issues and offers as an alternative energy resource. However, the DRM commercialized prospect and industrial utilization are curbed due to the weak prospect of sustained activity of the catalysts. The objective of this research is to find out the effects of the addition of CeO2 and La2O3 as promoters on the performance of the catalyst. In this work, catalysts such as Ni/Al2O3, Ni/Al2O3-CeO2, Ni/Al2O3-La2O3 were prepared by sol-gel method. The prepared catalysts have been characterized by XRD, BET analysis, and temperature-programmed reduction (TPR). BET results revealed that the addition of CeO2 and La2O3 slightly decreased the BET surface area of the synthesized catalyst because of the deposition on the porous structure of the support and filling its pores. The performance of the catalysts in DRM at 800°C shows that catalyst with CeO2 have the highest and stable conversion, while La2O3 has a significant role towards the stability of the reaction during the 8 h reaction on stream.