Direct synthesis of aromatics of jet fuel by integrating CO2-FTS and toluene alkylation reaction

Although considerable efforts have been made in CO2 hydrogenation to produce long-chain hydrocarbons through the CO2 Fischer-Tropsch (CO2-FTS) pathway, the selectivity of C8+ hydrocarbons is still low. This work reported a new strategy for the production of aromatics for jet fuel by coupling the CO2-FTS and toluene alkylation reactions over Fe&3Z5 catalysts with the jet fuel selectivity up to 75% under industrially relevant conditions. A series of characterization techniques and validation experiments were used to investigate the reaction pathway and mechanism of CO2 hydrogenation coupled to toluene alkylation over Fe&3Z5 catalysts. With the introduction of toluene, the olefin intermediates generated in situ from CO2 hydrogenation over iron-based catalysts were preferentially converted to aromatics of jet fuel by alkylation with toluene. Furthermore, low carbon number olefins were more readily alkylated with toluene at the acidic site of the Z5 zeolite. More significantly, the appropriate proximity of the two components of the tandem catalyst played a crucial role in the continuous and synergistic catalytic conversion of CO2 into aromatics of jet fuel. This study provides a viable technique for the highly selective synthesis of eco-friendly and carbon-neutral aromatics of jet fuel from CO2.