Effect of Rb promoter on Fe3O4 microsphere catalyst for CO2 hydrogenation to light olefins

Alkali metals have been widely studied to improve the efficiency of CO2 hydrogenation to light olefins on iron-based catalysts. Herein, a series of Rb-promoted Fe3O4 microsphere catalysts were developed to understand the effects of Rb promoter on the catalytic performance. The 3wt%Rb/Fe3O4 catalyst showed high selectivity of light olefins (C2–C4, 47.4%) with a high olefin/paraffin ratio (10.7). XRD, H2-TPR, CO2-TPD, XPS analyses show that the proper Rb loading rate may adjust carbonaceous species content and ferric oxide content on the surface of the catalyst which is help for the synergistic effect to produce light olefins.