Reporting the Bismuth Promotion for Green Methanol Synthesis by CO2 Hydrogenation over MgO-Supported Cu-Zn Catalysts

Due to the effective exploitation of carbon resources and concurrent decrease in the concentration of atmospheric carbon dioxide (CO2), the thermochemical conversion of CO2 into high-value chemical compounds has emerged as a significant research field. In this article, we report on the effective thermochemical conversion of CO2 for the synthesis of methanol by using Bi-promoted Cu-Zn/MgO catalysts. Cu-Zn bimetallic catalysts supported by MgO were created using the coprecipitation technique. The catalysts that were produced were subjected to varying concentrations of bismuth in order to examine their potential enhancing properties. Several analytical methods were applied to examine the physicochemical profile of the calcined catalysts. ICP-OES confirmed the actual bulk concentration of bismuth in each bismuth-supported Cu-Zn/MgO catalysts. X-ray diffraction studies revealed crystalline form of MgO catalysts support on one hand and high dispersion of Cu and Zn metal oxide on the MgO surface on the other. The study employed scanning electron microscopy (SEM) to examine the morphology of produced catalysts with uniform distribution, since this revealed their nanosize. The mesoporosity characteristic of Bi-promoted Cu-Zn/MgO catalysts was demonstrated by BET surface investigations. The catalytic performance of Bi-promoted Cu-Zn/MgO catalysts for methanol production by CO2 hydrogenation was revealed by activity data in liquid phase slurry reactor. The active profile of Bi could be further justified by comparative studies conducted for the current work with literature.