TY - JOUR
T1 - A model study on the carburization process of iron-based Fischer-Tropsch catalysts using in situ TEM-EELS
AU - Janbroers, S.
AU - Crozier, Peter
AU - Zandbergen, H. W.
AU - Kooyman, P. J.
PY - 2011/2/22
Y1 - 2011/2/22
N2 - In order to elucidate the activation mechanism of iron based Fischer-Tropsch catalysts, we performed in situ nanoscale structural and compositional analysis during carburization in CO atmosphere. We found that inside an ETEM at 20. Torr CO, hematite reduces while severe sintering occurs. This sintering is enhanced by low pressure conditions in combination with CO gas. The reduction inside the ETEM is so effective that metallic iron can be formed. During the process, about 50. nm sized iron carbide crystallites grow out of the iron (oxide) particles. Upon prolonged reaction, these newly formed crystallites reduce in size to about 5-30. nm. In contrast to what has been described in the literature until now, no carbon deposits were found on the outer rim of these iron carbides at high temperature conditions. Note however that, in contrast to our measurements, previous studies involved catalysts that were cooled or passivated prior to (TEM) analysis.
AB - In order to elucidate the activation mechanism of iron based Fischer-Tropsch catalysts, we performed in situ nanoscale structural and compositional analysis during carburization in CO atmosphere. We found that inside an ETEM at 20. Torr CO, hematite reduces while severe sintering occurs. This sintering is enhanced by low pressure conditions in combination with CO gas. The reduction inside the ETEM is so effective that metallic iron can be formed. During the process, about 50. nm sized iron carbide crystallites grow out of the iron (oxide) particles. Upon prolonged reaction, these newly formed crystallites reduce in size to about 5-30. nm. In contrast to what has been described in the literature until now, no carbon deposits were found on the outer rim of these iron carbides at high temperature conditions. Note however that, in contrast to our measurements, previous studies involved catalysts that were cooled or passivated prior to (TEM) analysis.
KW - Carburization
KW - Fischer-Tropsch
KW - TEM-EELS
UR - http://www.scopus.com/inward/record.url?scp=79551543468&partnerID=8YFLogxK
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U2 - 10.1016/j.apcatb.2010.12.034
DO - 10.1016/j.apcatb.2010.12.034
M3 - Article
AN - SCOPUS:79551543468
SN - 0926-3373
VL - 102
SP - 521
EP - 527
JO - Applied Catalysis B: Environmental
JF - Applied Catalysis B: Environmental
IS - 3-4
ER -