文献类型：期刊文献

英文题名：Revisiting the syngas conversion to olefins over Fe-Mn bimetallic catalysts: Insights from the proximity effects

作者：Ding, Xiaoxu[1];Zhu, Minghui[1];Han, Yi-fan[1];Yang, Zixu[1]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China

年份：2023

卷号：417

起止页码：213

外文期刊名：JOURNAL OF CATALYSIS

收录：;EI(收录号：20225213299718);WOS:【SCI-EXPANDED(收录号:WOS:000900255500008)】；

基金：Acknowledgements The authors greatly acknowledge the funding support from Shanghai Sailing Program (19YF1411000) and Open Fund of State Key Laboratory of Chemical Engineering (GZA01220102) .

语种：英文

外文关键词：Bimetallic catalyst; Self-combustion method; Fischer-Tropsch synthesis; Olefins; Structure transformation

摘要：Fe-Mn bimetallic catalysts have shown great promises in direct conversion of syngas to olefins via Fischer-Tropsch Synthesis (FTS). However, due to the structural complexity of Fe-based catalysts and the interference of secondary promoters, the promotional effects of Mn on phase transition of Fe -based FTS catalysts and catalytic performance are still under debate. Herein, Fe-Mn bimetallic catalysts were prepared from two different methods, namely solution combustion method (SCM) and co-precipitation (CP) method. Fe4Mn1-SCM exhibited an excellent C5+ selectivity (45 %) and stability over 100 h. In contrast, the product distribution given by Fe4Mn1-CP was dominated by C1-C4 hydrocarbons (85 %). The superior chain growth ability of the Fe4Mn1-SCM was attributed to the abundant interfacial Fe-MnOx structure, which retarded the oxygen removal and carbon diffusion process, resulting in less v- Fe5C2 phase but more e-Fe2.2C phase that was highly active for C-C coupling. Moreover, Mn-induced pro-motional effects were analyzed via kinetic measurements, physiochemical characterizations, Operando Raman-mass spectroscopy and theoretical calculations. It was found that the Fe-Mn proximity played a key role in controlling the interaction of structural and electronic impacts between Mn and Fe species. These findings may provide new insights for fabrication of Fe-based FTS catalysts with tunable product distribution. (c) 2022 Elsevier Inc. All rights reserved.