Methanol Synthesis by Hydrogenation of Hybrid CO2-CO Feeds

The impact of carbon monoxide on CO2-to-methanol catalysts has been scarcely investigated, although CO will comprise up to half of the carbon feedstock, depending on the origin of CO2 and process configuration. In this study, copper-based systems and ZnO-ZrO2 are assessed in cycling experiments with hybrid CO2-CO feeds and their CO sensitivity is compared to In2O3-based materials. All catalysts are found to be promoted upon CO addition. Copper-based systems are intrinsically more active in CO hydrogenation and profit from exploiting this carbon source for methanol production, whereas CO induces surplus formation of oxygen vacancies (i. e., the catalytic sites) on ZnO-ZrO2, as in In2O3-based systems. Mild-to-moderate deactivation occurs upon re-exposure to CO2-rich streams, owing to water-induced sintering for all catalysts except ZnO-ZrO2, which responds reversibly to feed variations, likely owing to its more hydrophobic nature and the atomic mixing of its metal components. Catalytic systems are categorized for operation in hybrid CO2-CO feeds, emphasizing the significance of catalyst and process design to foster advances in CO2 utilization technologies.

Automated summary

This study found that copper-based systems are more active in CO hydrogenation and suitable for methanol production using CO; ZnO-ZrO2 exhibits strong resistance to deactivation in CO2-rich streams, showing good reversibility; the research emphasizes the importance of catalyst and process design in advancing CO2 utilization technologies.