Study on a cobalt silica catalyst during reduction and Fischer–Tropsch reaction: In situ EXAFS compared to XPS and XRD
1998; Elsevier BV; Volume: 39; Issue: 4 Linguagem: Inglês
10.1016/s0920-5861(97)00124-7
ISSN1873-4308
AutoresBarbara Ernst, A. Bensaddik, L. Hilaire, P. Chaumette, A. Kiennemann,
Tópico(s)Catalysis and Hydrodesulfurization Studies
ResumoThe reduction of a 25 wt% Co/SiO2 catalyst for the hydrocarbon synthesis has been followed by several techniques: XRD, TPR, XPS and in situ EXAFS. Before reduction the cobalt is present as a Co3O4 spinel phase. A two-step reduction of Co3O4 to CoO and then to Co° is observed by EXAFS. This is consistent with XPS (surface) and TPR or XRD (bulk) studies. During CO/H2 reaction, cobalt is always in the metallic state (EXAFS). The coordination number of cobalt has been determined at each reduction step and during CO hydrogenation reaction.
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