Strategies in Pore-Structure engineering of hierarchical zeolites for Bio-Jet fuel production via catalytic fast...

The aviation industry's need to reduce carbon emissions makes biomass-derived sustainable aviation fuel (SAF) as a crucial alternative to conventional fossil-based jet fuel. Among various production routes, catalytic fast pyrolysis (CFP) over zeolites is a key technology for converting biomass into bio-jet fuel, yet conventional microporous zeolites often suffer from poor product selectivity and rapid deactivation. Creating hierarchical zeolites with secondary pore networks effectively optimizes mass transfer and acid-site distribution, thereby enhancing catalytic performance and stability. This review details the synthesis strategies for hierarchical zeolites, encompassing both bottom-up and top-down approaches for constructing intrinsic hierarchical porosity, as well as compaction and coating methods for fabricating composite zeolites. It further analyzes how critical factors, including precursor composition, pore-forming agent type, and synthesis conditions, govern the tailored engineering of the pore architecture. Furthermore, the catalytic performance of hierarchical zeolites in the CFP of feedstocks like lignocellulosic biomass and microalgae is then reviewed, highlighting their significant advantages in enhancing the selectivity toward key bio-jet fuel components (such as aromatic hydrocarbons), improving deoxygenation efficiency, and boosting coke resistance. Finally, future research directions for hierarchical zeolites are outlined, aiming to provide theoretical insights and technical guidance for the rational design of efficient catalysts dedicated to SAF production via biomass fast pyrolysis.