Hydrogenation of CO₂ to Light Olefins over ZnZrO_x /SSZ-13

Converting CO₂ to olefins is an ideal route to achieve carbon neutrality. However, selective hydrogenation to light olefins, especially single-component olefin, while reducing CH₄ formation remains a great challenge. Herein, we developed ZnZrO_x /SSZ-13 tandem catalyst for the highly selective hydrogenation of CO₂ to light olefins. This catalyst shows C₂ ⁼ -C₄ ⁼ and propylene selectivity up to 89.4 % and 52 %, respectively, while CH₄ is suppressed down to 2 %, and there is no obvious deactivation. It is demonstrated that the isolated moderate Brønsted acid sites (BAS) of SSZ-13 promotes the rapid conversion of intermediate species derived from ZnZrO_x , thereby enhancing the kinetic coupling of the reactions and inhibit the formation of alkanes and improve the light olefins selectivity. Besides, the weaker BAS of SSZ-13 promote the conversion of intermediates into aromatics with 4-6 methyl groups, which is conducive to the aromatics cycle. Accordingly, more propene can be obtained by elevating the Si/Al ratio of SSZ-13. This provides an efficient strategy for CO₂ hydrogenation to light olefins with high selectivity.