Fe-Co-K/ZrO₂ Catalytic Performance of CO₂ Hydrogenation to Light Olefins

In recent years, with the consumption of fossil resources and the large amount of CO 2 emissions, the energy crisis and the greenhouse question become deeply serious. The direct synthesis of olefins by CO 2 hydrogenation with iron-based catalysts is one of the best ways to achieve CO 2 reduction. In this study, zirconia (ZrO 2 )-supported iron-cobalt catalyst (Fe-Co/ZrO 2 ) and ZrO 2 -supported iron-cobalt-potassium catalyst (Fe-Co-K/ZrO 2 ) were prepared by impregnation method, which were used for CO 2 hydrogenation to light olefins (C 2 = -C 4 = ), and the effect of K on the catalytic activity were investigated emphatically. At the condition of 300 and 1.5 MPa, the activity test show that addition of K increases the CO 2 conversion from 40.8% to 44.8%, improves the selectivity of light olefins from 0.23% to 68.5%, and raises the stability of catalytic performance. The characterization results show that introduction of K improves electron cloud density of the iron species, enhances adsorption strength of the Fe to CO 2 , promotes the formation of iron carbide, and facilitates direct dissociation of CO 2 after adsorption on Fe species, thus boosts the performance of CO 2 hydrogenation to light olefins.