Design of a novel porous Fe2O3 cage catalyst for the production of gasoline fuels via coupling Fischer–Tropsch with zeolite cracking

Abstract

Designing an efficient zeolite-introduced novel Fe-based catalyst is essential for the direct production of gasoline fuels via coupling Fischer–Tropsch synthesis (FTS) and catalytic cracking reactions. Herein, we constructed a novel Fe₂O₃ cage catalyst with a hierarchical porous structure, which served as FTS sites for physically mixing with porous ZSM5 to provide catalytic cracking sites. The hybrid Fe + ZSM5(27) catalyst achieved an excellent gasoline fuel (C₅–C₁₁) selectivity of 62.7 wt%, outperforming traditionally supported and physically mixed catalysts. Moreover, the aromatic content was 22.1% in terms of C₅₊ hydrocarbons, which was within the range of the restricted aromatic content. The enhanced catalytic performance can be attributed to the Si/Al ratio governing the oligomerization reaction. ZSM5 with a suitable Si/Al ratio can promote the oligomerization of C₂–C₄ olefins to produce desired C₅–C₁₁ hydrocarbons. Fe + ZSM5(27) with a Si/Al ratio of 27 demonstrated a prominent CO conversion of 93.6% with a higher C₅–C₁₁ selectivity of 62.7 wt%. This work provides a promising strategy for designing multifunctional catalysts to modulate product distribution.