文献类型：期刊文献

英文题名：The study of structure-performance relationship of iron catalyst during a full life cycle for CO2 hydrogenation

作者：Zhang, Yulong[1];Cao, Chenxi[1];Zhang, Chao[1];Zhang, Zhengpai[1];Liu, Xianglin[1];Yang, Zixu[1];Zhu, Minghui[1];Meng, Bo[2];Xu, Jing[1];Han, Yi-Fan[1,2]

机构：[1]East China Univ Sci & Technol, State Key Lab Chem Engn, Shanghai 200237, Peoples R China;[2]Zhengzhou Univ, Res Ctr Heterogeneous Catalysis & Engn Sci, Sch Chem Engn & Energy, Zhengzhou 450001, Henan, Peoples R China

年份：2019

卷号：378

起止页码：51

外文期刊名：JOURNAL OF CATALYSIS

收录：;EI(收录号：20193707417486);WOS:【SCI-EXPANDED(收录号:WOS:000494887100006)】；

基金：National Natural Science Foundation of China (21878080, 21808058 and 21576084), Fundamental Research Funds for the Central Universities (222201718002 and 222201814006), China Postdoctoral Science Foundation (2019T120312) and Shanghai Sailing Program (18YF1406100) are greatly acknowledged for funding this work.

语种：英文

外文关键词：Operando spectroscopy; Iron catalyst; Full life cycle; Mechanism; Structure evolution

摘要：The establishment of structure-performance relationship of catalysts during a full life cycle is highly desirable for catalyst design and understanding of nature of active sites. As a case study, lower olefins synthesis directly from CO2 hydrogenation (CTO) was performed over iron catalyst and the catalyst structure evolution during its life cycle has been comprehensively studied. Particularly, operando techniques allow direct observation of the continuous phase transition during activation (Fe2O3 -> Fe5C2), reaction and deactivation (Fe5C2 -> Fe3O4), and regeneration (Fe3O4 -> Fe5C2) process, respectively. After a combined CO2-CO regeneration, 91.8% of the initial activity and 97.7% of the initial C-2-C-4 olefins selectivity were recovered. Our results indicate that the Fe5C2 phase is the active phase for C-2-C-4 olefins production. The iron carbide phases are irreversibly oxidized to Fe3O4 under CTO conditions, which is the major factor responsible for the catalyst deactivation. This study not only reveals the dynamic structure evolution of iron catalyst during the full life cycle in CTO, but also endows deep insight into the underlying deactivation mechanism. (C) 2019 Elsevier Inc. All rights reserved.