A model study on the carburization process of iron-based Fischer–Tropsch catalysts using in situ TEM–EELS
作者： S. Janbroers , P.A. Crozier , H.W. Zandbergen , P.J. Kooyman
DOI: 10.1016/J.APCATB.2010.12.034
关键词: Oxide 、 Sintering 、 Catalysis 、 Carbide 、 Hematite 、 Carbon 、 Crystallite 、 Metallurgy 、 Materials science 、 Fischer–Tropsch process
摘要: Abstract In order to elucidate the activation mechanism of iron based Fischer–Tropsch catalysts, we performed in situ nanoscale structural and compositional analysis during carburization CO atmosphere. We found that inside an ETEM at 20 Torr CO, hematite reduces while severe sintering occurs. This is enhanced by low pressure conditions combination with gas. The reduction so effective metallic can be formed. During process, about 50 nm sized carbide crystallites grow out (oxide) particles. Upon prolonged reaction, these newly formed reduce size 5–30 nm. contrast what has been described literature until now, no carbon deposits were on outer rim carbides high temperature conditions. Note however that, our measurements, previous studies involved catalysts cooled or passivated prior (TEM) analysis.
elsevier.com
sci-hub.se 参考文章(39)
M. Rálek, Robert Bernard Anderson, Herbert Kölbel, The Fischer-Tropsch Synthesis ,(1984)
Calvin H. Bartholomew, Matthew W. Stoker, Linda Mansker, Abhaya Datye, Effects of pretreatment, reaction, and promoter on microphase structure and Fischer-Tropsch activity of precipitated iron catalysts Studies in Surface Science and Catalysis. ,vol. 126, pp. 265- 272 ,(1999) , 10.1016/S0167-2991(99)80475-3
Adeyinka A. Adeyiga, DEVELOPMENT OF ATTRITION RESISTANT IRON-BASED FISCHER-TROPSCH CATALYSTS Other Information: PBD: 1 Dec 2003. ,(2003) , 10.2172/826366
T.R. Motjope, H.T. Dlamini, H. Pollak, N.J. Coville, Effect of precipitating agent on the catalytic behaviour of precipitated iron catalysts Hyperfine Interactions. ,vol. 120, pp. 763- 767 ,(1999) , 10.1023/A:1017016900109
Mehul D. Shroff, Abhaya K. Datye, The importance of passivation in the study of iron Fischer-Tropsch catalysts Catalysis Letters. ,vol. 37, pp. 101- 106 ,(1996) , 10.1007/BF00813526
Robert J. O'Brien, Liguang Xu, Diane R. Milburn, Yong-Xi Li, Kenneth J. Klabunde, Burtron H. Davis, Fischer-Tropsch synthesis: Impact of potassium and zirconium promoters on the activity and structure of an ultrafine iron oxide catalyst Topics in Catalysis. ,vol. 2, pp. 1- 15 ,(1995) , 10.1007/BF01491951
D.B. Bukur, K. Okabe, M.P. Rosynek, C.P. Li, D.J. Wang, K.R.P.M. Rao, G.P. Huffman, Activation studies with a precipitated iron catalyst for Fischer-Tropsch synthesis. I. Characterization studies Journal of Catalysis. ,vol. 155, pp. 353- 365 ,(1995) , 10.1006/JCAT.1995.1217
R DIFFENBACH, The role of pH in the performance of precipitated iron Fischer-Tropsch catalysts Journal of Catalysis. ,vol. 100, pp. 466- 476 ,(1986) , 10.1016/0021-9517(86)90113-2
T.R. Motjope, H.T. Dlamini, G.R. Hearne, N.J. Coville, Application of in situ Mössbauer spectroscopy to investigate the effect of precipitating agents on precipitated iron Fischer–Tropsch catalysts Catalysis Today. ,vol. 71, pp. 335- 341 ,(2002) , 10.1016/S0920-5861(01)00460-6
S. Janbroers, T.R. de Kruijff, Q. Xu, P.J. Kooyman, H.W. Zandbergen, Preparation of Carbon-Free TEM Microgrids by Metal Sputtering Ultramicroscopy. ,vol. 109, pp. 1105- 1109 ,(2009) , 10.1016/J.ULTRAMIC.2009.04.001