Selective Hydrogenation of alpha,beta-Unsaturated Aldehydes and Ketones using Novel Manganese Oxide and Platinum Supported on Manganese Oxide Octahedral Molecular Sieves as Catalysts

Haresh G. Manyar, Bo Yang, Helen Daly, Helen Moor, Stephen McMonagle, Yu Tao, Ganapati D. Yadav, Alexandre Goguet, P. Hu, Christopher Hardacre*

*Corresponding author for this work

Research output: Contribution to journalArticlepeer-review

52 Citations (Scopus)

Abstract

The selective hydrogenation of ,-unsaturated aldehydes and ketones has been studied using ketoisophorone and cinnamaldehyde as model substrates using manganese oxide octahedral molecular sieve (OMS-2) based catalysts. For the first time, OMS-2 has been shown to be an efficient and selective hydrogenation catalyst. High selectivities for either the CC or CO double bond at approximate to 100% conversion were achieved by using OMS-2 and platinum supported on OMS-2 catalysts. Density functional theory (DFT) calculations showed that the dissociation of H2 on OMS-2 was water assisted and occurred on the surface Mn of OMS-2(001) that had been modified by an adsorbed H2O molecule. The theoretically calculated activation barrier was in good agreement with the experimentally determined value for the hydrogenation reactions, indicating that H2 dissociation on OMS-2 is likely to be the rate-determining step. A significant increase in the rate of reaction was observed in the presence of Pt as a result of the enhancement of H2 dissociative adsorption and subsequent reaction on the Pt or spillover of the hydrogen to the OMS-2 support. The relative adsorption strengths of ketoisophorone and cinnamaldehyde on the OMS-2 support compared with the Pt were found to determine the product selectivity.

Original languageEnglish
Pages (from-to)506-512
Number of pages7
JournalCHEMCATCHEM
Volume5
Issue number2
Early online date29 Oct 2012
DOIs
Publication statusPublished - Feb 2013

Keywords

  • aldehydes
  • density functional calculations
  • hydrogenation
  • ketones
  • microporous materials
  • manganese
  • DENSITY-FUNCTIONAL THEORY
  • TOTAL-ENERGY CALCULATIONS
  • AUGMENTED-WAVE METHOD
  • BASIS-SET
  • OXIDATION
  • SURFACES
  • OMS-2
  • DECOMPOSITION
  • DISSOCIATION
  • EFFICIENT

ASJC Scopus subject areas

  • Inorganic Chemistry
  • Organic Chemistry
  • Physical and Theoretical Chemistry
  • Catalysis

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