Ni catalysts modified with mesoporous silica support: The role of Pr2O3 and MgO on the methanation of CO2

Abstract

One way to solve environmental and energy related problems is to use carbon dioxide as a raw material along with renewable H2 to make useful chemicals and goods from those alternative energy sources. Several compositions of xNi-MCM-41/MgO-Pr2O3 were used for CO2 methanation via the hydrothermal synthesis method. Techniques such as TEM, H2-TPD, XRD, SEM, and BET were used to study the influence of the mechanism of the catalyst during CO2 methanation. The best performance was obtained for the 1.5 % Ni-MCM-41/MgO-Pr2O3 catalyst at 400 °C and normal atmospheric pressure, where the CO2 conversion efficiency and selectivity were 87.4 and 99.9 %, respectively. It was thought that the synergistic effects between the Ni active sites, the promoter, and the support were important for the high reactivity of the catalysts. These effects included better Ni dispersion and more CO2 adsorption sites due to the inclusion of MgO-Pr2O3. The promoted catalyst retained its high reactivity after 30 h on stream as observed during the stability test.