Selective catalytic oxidation of CO: Effect of chloride on supported Au catalysts

Harold H Kung, M. C. Kung, H. S. Oh, J. H. Yang, C. K. Costello

Research output: Contribution to journalArticle

94 Citations (Scopus)

Abstract

Supported Au catalysts are generally prepared from chloride-containing Au precursors and their characteristics are highly sensitive to preparation procedures. To better understand and control the variables important in the preparation of these catalysts, the effect of chloride on the catalytic performances of highly active Au/Al2O3 catalysts in the selective catalytic oxidation of CO (SCO) was studied. The complex manner in which Cl- affected Au catalysis was deconvoluted in a series of complementary experiments where chloride was quantitatively removed and added. The residual chloride affected the activities in two different ways, i.e., it facilitated the agglomeration of Au particles during heat treatment and it inhibited the catalytic activity by poisoning the active site. Chloride poisoning was not only observed at the steady state, it was more pronounced in the transient toward steady state. To better assess the poisoning effect of Cl-, phosphate was introduced to the support surface as a postsynthesis treatment before the addition of CI- in some experiments. Activity suppression was observable at a Cl-/Au molar ratio as low as 0.0006. Thus a very small fraction of gold was related to the active site. This implied that the activity per active site was extremely high.

Original languageEnglish
Pages (from-to)375-386
Number of pages12
JournalJournal of Catalysis
Volume210
Issue number2
DOIs
Publication statusPublished - Sep 10 2002

Fingerprint

Catalyst poisoning
Catalytic oxidation
Carbon Monoxide
Catalyst supports
Chlorides
chlorides
poisoning
catalysts
oxidation
Catalysts
Catalysis
Catalyst activity
Phosphates
Agglomeration
Gold
Experiments
Heat treatment
preparation
agglomeration
catalysis

Keywords

  • Chloride
  • Gold
  • Poisoning
  • Selective CO oxidation

ASJC Scopus subject areas

  • Catalysis
  • Process Chemistry and Technology

Cite this

Selective catalytic oxidation of CO : Effect of chloride on supported Au catalysts. / Kung, Harold H; Kung, M. C.; Oh, H. S.; Yang, J. H.; Costello, C. K.

In: Journal of Catalysis, Vol. 210, No. 2, 10.09.2002, p. 375-386.

Research output: Contribution to journalArticle

Kung, Harold H ; Kung, M. C. ; Oh, H. S. ; Yang, J. H. ; Costello, C. K. / Selective catalytic oxidation of CO : Effect of chloride on supported Au catalysts. In: Journal of Catalysis. 2002 ; Vol. 210, No. 2. pp. 375-386.
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