Highly Selective Conversion of Carbon Dioxide to Methanol through a Cu-ZnO-Al₂O₃-ZrO₂/Cu-MOR Tandem Catalyst

Methanol formation from CO2 hydrogenation attracts great attention in view of utilization of carbon resources. However, CO2 transformation to methanol is challenging because of the thermodynamic equilibrium restriction and water-caused catalyst deactivation. It is desired, therefore, to develop highly active, selective and stable catalysts for CO2 hydrogenation to methanol. Herein, we propose a novel tandem catalyst composed of Cu-ZnO-Al2O3-ZrO2 (CZAZ) and Cu-MOR for highly selective conversion of CO2 to methanol. During CO2 hydrogenation by the CZAZ catalyst, the by-product methane is continuously transformed to methanol through reaction with water via the Cu-MOR catalyst, thus enhancing CO2 conversion and methanol selectivity. Under mild reaction conditions (200 & DEG;C and 3.0 MPa), high CO2 conversion (40.7 %) and methanol selectivity (97.6 %) are achieved, outperforming state-of-the-art CO2 hydrogenation catalysts. Further, water-caused deactivation of the catalyst through aggregation and densification is suppressed owing to water consumption via methane oxidation to methanol, validating a high CZAZ/Cu-MOR tandem catalyst stability.