Cyclohexane oxidative dehydrogenation over copper oxide catalysts

Scott L. Nauert, Fabian Schax, Christian Limberg, Justin M Notestein

Research output: Contribution to journalArticle

7 Citations (Scopus)

Abstract

Here, we report on structure-reactivity trends for cyclohexane oxidative dehydrogenation (ODH) with silica supported copper oxide catalysts as a function of surface structure. Copper oxide was supported on mesostructured KIT-6 silica at low surface densities 2 using copper (II) nitrate, ammonium and sodium copper (II) ethylenediaminetetraacetate, and a hexanuclear copper (I) siloxide complex. Copper oxide surface structures were characterized by X-ray absorption spectroscopy as well as ambient and in situ diffuse reflectance UV–visible (DRUV–vis) spectroscopy to determine trends in copper oxide nuclearity. DRUV–vis spectroscopy identifies three copper species based on Cu2+ ligand to metal transfer (LMCT) bands at 238, 266, and >300 nm as well as Cu+ LMCT bands at 235, 296, and 312 nm. Counterintuitively, EXAFS analysis shows that the multinuclear precursor leads to fewer average Cu–Cu interactions than syntheses with mononuclear copper salt precursors. Turnover frequency and selectivity to benzene increase with decreasing copper oxide nuclearity, and thus the multinuclear precursor leads to the highest turnover frequency and benzene production. This work shows the variety of surface species that exist even at extremely low copper surface densities, control of which can improve reactivity of an atypical ODH catalyst up to rates comparable to benchmark vanadia catalysts.

Original languageEnglish
Pages (from-to)180-190
Number of pages11
JournalJournal of Catalysis
Volume341
DOIs
Publication statusPublished - Sep 1 2016

Fingerprint

Copper oxides
copper oxides
Dehydrogenation
Cyclohexane
dehydrogenation
cyclohexane
Copper
catalysts
copper
Catalysts
Benzene
Surface structure
Silicon Dioxide
Spectroscopy
reactivity
benzene
Silica
X ray absorption spectroscopy
silicon dioxide
sodium nitrates

Keywords

  • Copper oxide
  • Cyclohexane
  • KIT-6
  • Oxidative dehydrogenation

ASJC Scopus subject areas

  • Catalysis
  • Physical and Theoretical Chemistry

Cite this

Cyclohexane oxidative dehydrogenation over copper oxide catalysts. / Nauert, Scott L.; Schax, Fabian; Limberg, Christian; Notestein, Justin M.

In: Journal of Catalysis, Vol. 341, 01.09.2016, p. 180-190.

Research output: Contribution to journalArticle

Nauert, Scott L. ; Schax, Fabian ; Limberg, Christian ; Notestein, Justin M. / Cyclohexane oxidative dehydrogenation over copper oxide catalysts. In: Journal of Catalysis. 2016 ; Vol. 341. pp. 180-190.
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