Impact of Mo Promoter and In Situ Assembled MOF on Al2O3-Supported Catalysts for the CO2-to-Methanol Reaction

In this study, in situ assembled MOFs on Al2O3-supported catalysts were prepared to compare with the traditional Al2O3-supported catalysts promoted with Ga and Mo for CO2 hydrogenation to methanol reaction. Among supported catalysts, the 5%MoZnCu/Al2O3 catalyst exhibited the highest CO2 conversion and methanol selectivity, while the 2.5%Mo-modified catalyst demonstrated the best performance among MOF-composited catalysts. MOF compositing can enhance the surface area and pore size of the catalyst, yielding increased CO2 conversion at 230 °C and 3.0 MPa. Meanwhile, Mo modification enhanced the methanol selectivity. Characterization data from XRD, Raman spectroscopy, and BET surface area analysis revealed that the crystal structure, surface morphology, pore structure, and metal valence distribution of the active components were influenced by the metallic promoters. This study provides valuable insights into catalyst development for efficient CO2 hydrogenation to produce methanol.