Preparation of Ni-ZrO2 catalyst via the Pechini sol-gel method for CO2 methanation

Abstract

This investigation utilized a Pechini (sol-gel) method to prepare a Ni-ZrO2 catalyst for the CO2 methanation reaction, which is a crucial reaction that can promote the transition of renewable energy by producing storable methane fuel. By using this reaction to evaluate the catalytic activity of the prepared catalysts, a suitable citric acid molar ratio and calcination temperature in the preparation were chosen. Several techniques, including XRD, SEM, H2-TPR, CO2-TPD, and N2 physisorption, were employed to characterize the sample with the best performance. The catalyst prepared with a citric acid/metallic precursors molar ratio of 1/1, and a calcination temperature of 650 °C was found to induce the best catalytic performance among tested samples with a 50% CO2 conversion temperature of 323 °C. This performance is attributed to a synergy of the catalyst’s physicochemical properties, including a small nickel crystallite size of 28.9 nm, an average surface area of 44.6 m2/g, a reduction degree of 52.7%, and a basicity of 0.42 mmol/g.