Effect of MgO on the catalytic activity and stability of nickel-based catalyst in methane dry reforming reaction.

The present study investigates the efficacy of various MgO loadings on enhancing the catalytic resistance to carbon formation over nickel-based catalysts during the dry reforming of methane (DRM). One of the primary challenges in this reaction is carbon deposition, primarily derived from CO decomposition through the Boudouard reaction. This process leads to carbon formation, which creates a spatial barrier between the reactants and the active sites, resulting in a significant decline in catalytic performance. Given the acidic nature of CO2, MgO, an alkaline earth metal, can serve as an alkali component to improve catalyst performance. By increasing the basicity of the catalyst, MgO enhances CO2 adsorption on the catalyst surface, which competitively suppresses the progression of the Boudouard reaction. In this study, a range of MgO loadings (5%, 25%, 45%, 65%, and 85%) was evaluated in conjunction with a fixed NiO content (10%). The findings from TPO and SEM analyses indicate that increasing MgO content substantially reduces carbon deposition on the catalyst surface. Among the tested formulations, the 10%NiO-45%MgO-Al2O3 catalyst, with a methane conversion of 66.57% at 700 °C demonstrated exceptional catalytic activity for CH4 conversions. Additionally, it exhibited remarkable long-term stability under reaction conditions.