2026-10-14T16:35:29Z https://www.scidb.cn/oai

10.57760/sciencedb.013rh 2026-09-24T14:21:49Z

2026-09-24 Synthesis and Catalytic Performance of Short b-Axis ZSM-5 Zeolite Regulated by Seed and Fluoride Ion doi:10.57760/sciencedb.013rh en The straight b-axis channels in ZSM-5 zeolites play a crucial role in the mass transfer of macromolecular products and the stability of the catalytic system. In this work, short b-axis ZSM-5 zeolites were synthesized via a Silicalite-1 seed suspension induction strategy combined with fluoride ion (F-) assisted regulation. Using CO2 hydrogenation to aromatics as a probe reaction, the effect of the straight b-axis channels on product distribution and anti-coking performance was investigated. Systematic investigation into the effect of gel composition on the crystallization process and morphology of ZSM-5 zeolites revealed that the introduced Silicalite-1 seed suspension provided abundant nucleation centers, while appropriate amounts of TPAOH and F⁻ synergistically regulated the mineralization and growth of specific crystal facets. The b-axis thickness of the optimal zeolite sample (SS-3) was reduced to approximately 29 nm, and its external surface area was increased by 3.5 times compared to that of conventional micrometer-sized ZSM-5 zeolites. Evaluation of the bifunctional catalyst constructed by compounding SS-3 with Fe-Mn oxide (FM) for CO₂ hydrogenation to aromatics showed that the proportion of aromatics in the C5+ products of the FM/SS-3 catalyst system reached 83.5%, and the aromatics selectivity (53.5%) was more than twice that of the commercial micrometer-sized zeolite system. During a 100 h continuous operation, the FM/SS-3 catalyst exhibited excellent stability, with a coke weight loss of only 8.7% for the spent zeolite (compared to 12.2% for the commercial sample). This is mainly attributed the combined advantages of the short b-axis morphology, increased external specific surface area, and the resulting improved accessibility of active sites, which promotes the rapid desorption and escape of aromatic molecules generated by olefin aromatization, and inhibits secondary deep condensation and carbon deposition deactivation caused by diffusion limitations. This work provides fundamental experimental data for the controllable synthesis of short b-axis ZSM-5 zeolites and their application in CO2 hydrogenation to aromatics. short b-axis ZSM-5; seed suspension; CO2 hydrogenation to aromatics; bifunctional catalyst; morphology control. Lv Yujuan Li Jinxing Chen Chen Xie Jiaxin zhao yin di Liu Suyao PUBLIC https://creativecommons.org/licenses/by/4.0/ dataset Science Data Bank