Recent developments in the surface and catalytic chemistry of supported organoactinides

Moris S. Eisen, Tobin J Marks

Research output: Contribution to journalArticle

37 Citations (Scopus)

Abstract

The adsorption of organoactinide complexes on dehydroxylated alumina (DA) yields coordinatively unsaturated, highly active catalysts for several demanding chemical transformations. Thus, in the case of Th(η3-allyl)4 supported on dehydroxylated γ-alumina (DA), facile arene hydrogenation and alkane activation processes can be effected in slurry reactions at 90°C and PH2 = 30-180 psi. Benzene reduction occurs at a turnover frequency of ≈ 25000 h-1 per active site and cyclohexane CH exchange with D2 at ≈ 1300 h-1 per active site. Active site characterization using D2O poisoning, hydrogenolysis, and CH3Cl dosing indicates ≤ 8 ± 1 % of the Th surface sites are catalytically significant. EPR and XPS spectroscopy provide no evidence for Th oxidation states less than +4. The mechanisms for the above processes are discussed in terms of electrophilic "four-center" activation processes in which the active sites appear to bear sterically significant, nonhydridic ancillary ligation.

Original languageEnglish
Pages (from-to)23-50
Number of pages28
JournalJournal of Molecular Catalysis
Volume86
Issue number1-3
DOIs
Publication statusPublished - Jan 3 1994

    Fingerprint

Keywords

  • alkane activation
  • allyl complexes
  • arenes
  • heterogeneous catalysis
  • hydrogenation
  • thorium

ASJC Scopus subject areas

  • Engineering(all)

Cite this