Cobalt aluminate formation in alumina-supported cobalt catalysts: Effects of cobalt reduction state and water vapor

Amornmart Sirijaruphan, A. Horváth, James G. Goodwin, Rachid Oukaci

Research output: Contribution to journalArticle

60 Citations (Scopus)

Abstract

This research was focused at getting deeper insight into the circumstances of "cobalt aluminate" formation in alumina-supported cobalt catalysts. It was desired to determine which state(s) of cobalt (i.e. reduced or oxidized) and what reaction conditions play a significant role in the aluminate formation at the relatively mild conditions used for reduction or Fischer-Tropsch synthesis. Reduction and hydrothermal pretreatments were applied to influence the formation of nonreducible Co-support compounds. Temperature-programmed reduction (TPR) was used to measure the amount of reducible cobalt compounds formed in 20 wt% Co/Al2O3 catalyst. The results reveal that the presence of partially reduced cobalt in a well-dispersed form is required for the formation of cobalt aluminate. The presence of water vapor promotes cobalt aluminate formation probably by hydrating the alumina and possibly by partially reoxidizing highly dispersed cobalt.

Original languageEnglish
Pages (from-to)89-94
Number of pages6
JournalCatalysis Letters
Volume91
Issue number1-2
DOIs
Publication statusPublished - Nov 2003

Fingerprint

Aluminum Oxide
Steam
Cobalt
Water vapor
water vapor
Alumina
cobalt
aluminum oxides
vapors
catalysts
Catalysts
Cobalt compounds
cobalt compounds
Fischer-Tropsch synthesis
pretreatment
synthesis

Keywords

  • Co/AlO
  • Cobalt aluminate formation
  • Cobalt reducibility
  • Hydrothermal treatment

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry
  • Catalysis

Cite this

Cobalt aluminate formation in alumina-supported cobalt catalysts : Effects of cobalt reduction state and water vapor. / Sirijaruphan, Amornmart; Horváth, A.; Goodwin, James G.; Oukaci, Rachid.

In: Catalysis Letters, Vol. 91, No. 1-2, 11.2003, p. 89-94.

Research output: Contribution to journalArticle

Sirijaruphan, Amornmart ; Horváth, A. ; Goodwin, James G. ; Oukaci, Rachid. / Cobalt aluminate formation in alumina-supported cobalt catalysts : Effects of cobalt reduction state and water vapor. In: Catalysis Letters. 2003 ; Vol. 91, No. 1-2. pp. 89-94.
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