Design of novel hierarchical cage active particles and zeolite for the direct conversion of syngas to gasoline fuel

Abstract

Although the direct conversion of syngas to gasoline fuel offers a promising route to produce liquid fuel from non-petroleum carbon resources, it remains a great challenge owing to low target product selectivity and poor catalyst stability. Hence, we designed a bifunctional catalyst consisting of SiO₂-coated novel hierarchical porous cage active particles and hierarchical porous zeolite, which provided a C₅–C₁₁ hydrocarbon selectivity of 63.5 wt%, and the yield reached 99.3% in C₅₊ hydrocarbons, with an aromatic content of 25.7% at 280 °C. Particularly, this value is within the range of the restricted aromatic content. As the reaction temperature was elevated to 310 °C, zeolite-24 presented an excellent aromatic selectivity of 64.4% in liquid hydrocarbons. This is mainly because the zeolite provides higher acidity at a rather high reaction temperature, facilitating the formation of hydrocarbons in the liquid phase, which were predominantly aromatics rather than i-C₅₊. Besides aromatics, a high i-C₅₊ content of 77.4% in liquid hydrocarbons was obtained at 280 °C over FeZ-16. At the given condition, the synthesized hybrid catalysts were beneficial for the production of gasoline fuels consisting of aromatics and i-C₅₊. Particularly, 280 °C offered optimum selectivity to i-C₅₊, and 310 °C was suitable for the formation of aromatics. This work provides a strategy for the design and preparation of novel and efficient catalysts for gasoline production.