Tailoring strontium-promoted alumina-zirconia supported Ni-catalysts for enhanced CO2 utilization via dry reforming of methane: Sr loading effects and process optimization
Ahmed S. Al‐Fatesh, Maher M. Alrashed, Radwa A. El‐Salamony, Mai Hassan Roushdy, Saba M. Alwan, Ahmed I. Osman, Mohammed O. Bayazed, Anis H. Fakeeha, Ahmed A. Ibrahim, Rawesh Kumar
Abstract
An urgent need exists in the dry reforming of methane (DRM) community for a cost-effective and high-performance catalyst system to facilitate the industrial production of H2-rich syngas. In this study, we propose a catalyst composed of a 10 wt% ZrO2-90 wt% Al2O3 support, Ni as active sites, and a strontium promoter, which offers a promising solution. Characterization of the 5NixSr/10Zr+Al catalyst series (x = 0–4 wt%) was conducted using XRD, surface area and porosity analysis, and TPR, TPO, TPD techniques, revealing the stability of metallic Ni derived from the reduction of "moderately interacted NiO-species" under oxidizing-reducing conditions. Incorporating 3 wt% Sr in the 5Ni/10Zr+Al catalyst enhanced reducibility and promoted efficient oxidation of carbon deposits by CO2. The resulting 5Ni3Sr/10Zr+Al catalyst exhibited additional strong basic sites, leading to ∼82% H2 yield and effective inhibition of parallel H2-consuming reactions. Remarkably, the H2 yield remained stable at ∼79% over a 51-hour time on stream, while process optimization using response surface methodology yielded an optimized H2 yield of 89% under specific conditions. Experimental validation demonstrated an H2 yield of 87.4% with excellent stability for a 10-hour time on stream. Overall, the proposed catalyst system demonstrates cost-effectiveness, high performance, and stability, making it a promising candidate for DRM applications.