skip to main content

DOE PAGESDOE PAGES

Title: Iron Carbides in Fischer–Tropsch Synthesis: Theoretical and Experimental Understanding in Epsilon-Iron Carbide Phase Assignment

As active phases in low-temperature Fischer–Tropsch synthesis for liquid fuel production, epsilon iron carbides are critically important industrial materials. However, the precise atomic structure of epsilon iron carbides remains unclear, leading to a half-century of debate on the phase assignment of the ε-Fe 2C and ε’-Fe 2.2C. Here, we resolve this decades-long question by a combining theoretical and experimental investigation to assign the phases unambiguously. First, we have investigated the equilibrium structures and thermal stabilities of ε-Fe xC, (x = 1, 2, 2.2, 3, 4, 6, 8) by first-principles calculations. We have also acquired X-ray diffraction patterns and Mössbauer spectra for these epsilon iron carbides, and compared them with the simulated results. These analyses indicate that the unit cell of ε-Fe 2C contains only one type of chemical environment for Fe atoms, while ε’-Fe 2.2C has six sets of chemically distinct Fe atoms.
Authors:
 [1] ;  [2] ;  [3] ;  [1] ;  [1] ; ORCiD logo [4] ;  [2] ;  [5] ;  [1] ;  [1] ; ORCiD logo [1]
  1. Chinese Academy of Sciences (CAS), Beijing (China); Synfuels China Co., Beijing (China)
  2. Univ. of California, Berkeley, CA (United States)
  3. Beijing Univ. of Technology (China)
  4. Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
  5. Synfuels China Co., Beijing (China)
Publication Date:
Report Number(s):
LA-UR-17-25066
Journal ID: ISSN 1932-7447; TRN: US1703118
Grant/Contract Number:
AC52-06NA25396
Type:
Accepted Manuscript
Journal Name:
Journal of Physical Chemistry. C
Additional Journal Information:
Journal Volume: 121; Journal Issue: 39; Journal ID: ISSN 1932-7447
Publisher:
American Chemical Society
Research Org:
Los Alamos National Lab. (LANL), Los Alamos, NM (United States)
Sponsoring Org:
USDOE Office of Science (SC). Basic Energy Sciences (BES) (SC-22)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY; Material Science
OSTI Identifier:
1402643

Liu, Xing-Wu, Cao, Zhi, Zhao, Shu, Gao, Rui, Meng, Yu, Zhu, Jian-Xin, Rogers, Cameron, Huo, Chun-Fang, Yang, Yong, Li, Yong-Wang, and Wen, Xiao-Dong. Iron Carbides in Fischer–Tropsch Synthesis: Theoretical and Experimental Understanding in Epsilon-Iron Carbide Phase Assignment. United States: N. p., Web. doi:10.1021/acs.jpcc.7b06104.
Liu, Xing-Wu, Cao, Zhi, Zhao, Shu, Gao, Rui, Meng, Yu, Zhu, Jian-Xin, Rogers, Cameron, Huo, Chun-Fang, Yang, Yong, Li, Yong-Wang, & Wen, Xiao-Dong. Iron Carbides in Fischer–Tropsch Synthesis: Theoretical and Experimental Understanding in Epsilon-Iron Carbide Phase Assignment. United States. doi:10.1021/acs.jpcc.7b06104.
Liu, Xing-Wu, Cao, Zhi, Zhao, Shu, Gao, Rui, Meng, Yu, Zhu, Jian-Xin, Rogers, Cameron, Huo, Chun-Fang, Yang, Yong, Li, Yong-Wang, and Wen, Xiao-Dong. 2017. "Iron Carbides in Fischer–Tropsch Synthesis: Theoretical and Experimental Understanding in Epsilon-Iron Carbide Phase Assignment". United States. doi:10.1021/acs.jpcc.7b06104. https://www.osti.gov/servlets/purl/1402643.
@article{osti_1402643,
title = {Iron Carbides in Fischer–Tropsch Synthesis: Theoretical and Experimental Understanding in Epsilon-Iron Carbide Phase Assignment},
author = {Liu, Xing-Wu and Cao, Zhi and Zhao, Shu and Gao, Rui and Meng, Yu and Zhu, Jian-Xin and Rogers, Cameron and Huo, Chun-Fang and Yang, Yong and Li, Yong-Wang and Wen, Xiao-Dong},
abstractNote = {As active phases in low-temperature Fischer–Tropsch synthesis for liquid fuel production, epsilon iron carbides are critically important industrial materials. However, the precise atomic structure of epsilon iron carbides remains unclear, leading to a half-century of debate on the phase assignment of the ε-Fe2C and ε’-Fe2.2C. Here, we resolve this decades-long question by a combining theoretical and experimental investigation to assign the phases unambiguously. First, we have investigated the equilibrium structures and thermal stabilities of ε-FexC, (x = 1, 2, 2.2, 3, 4, 6, 8) by first-principles calculations. We have also acquired X-ray diffraction patterns and Mössbauer spectra for these epsilon iron carbides, and compared them with the simulated results. These analyses indicate that the unit cell of ε-Fe2C contains only one type of chemical environment for Fe atoms, while ε’-Fe2.2C has six sets of chemically distinct Fe atoms.},
doi = {10.1021/acs.jpcc.7b06104},
journal = {Journal of Physical Chemistry. C},
number = 39,
volume = 121,
place = {United States},
year = {2017},
month = {9}
}