Ternary system with sandwich configuration facilitates aromatic production from CO2 hydrogenation

Enhancing the selectivity of light olefin intermediates is crucial for efficiently synthesizing aromatic hydrocarbons from CO2 hydrogenation. However, due to the limitations of Anderson-Schulz-Flory law, the oriented synthesis of light olefins over Fe-based catalysts is challenging. Herein, we creatively insert Y zeolite between the Fe-based catalyst and ZSM-5 zeolite to form a sandwich configuration. The excellent cracking function of sandwich Y zeolite enables the products before the aromatization to be concentrated in the light unsaturated hydrocarbons, leading to a high aromatic selectivity during the succedent aromatization processes. With the assistance of Y zeolite, the light olefin selectivity of the K-Fe catalyst increases from 30.8 % to 40.3 %. After combining with ZSM-5 zeolite, the aromatic selectivity of the ternary system is boosted from 27.6 % to 51.5 % compared to the bifunctional catalysts without Y zeolite. Our studies offer insightful guidance for the rational utilization of multifunctional zeolites to directly synthesize target products. [Display omitted] •The ternary system with sandwich configuration markedly facilitates the synthesis of aromatics.•The introduction of Y zeolite increases the light olefin selectivity from 30.8 % to 40.3 %.•Aromatic selectivity is promoted from 27.6 % to 51.5 % with the sandwich configuration.