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Title: Citral Hydrogenation over Dilute Alloy Catalysts
Abstract

Dilute alloy CuPt and NiPt catalysts are studied in the hydrogenation of citral, a model α,β‐unsaturated aldehyde.In situandex situcharacterization is used to demonstrate that the Pt species within these nanoparticles are well dispersed and approach a single atom alloy structure. The distribution of Pt varies between the two host metal systems; under a hydrogen environment, the nanoparticle surface and near‐surface region of the NiPt nanoparticles is Pt rich, while the Pt is more uniformly distributed throughout the CuPt nanoparticles. When used for citral hydrogenation reactions, a rate enhancement is observed upon the addition of Pt to the Cu or Ni host catalysts, however this enhancement is determined to be due to the presence of additional metal and not a synergistic effect of the two metals. The Pt structure does, nonetheless, influence the observed selectivity trends. NiPt/SiO2catalysts have high selectivity to the unsaturated aldehyde citronellal while the CuPt/SiO2catalysts have increased selectivity to unsaturated alcohol products. This increased selectivity is attributed to a combination of hydrogen dissociation over Pt sites and a decrease in size of Cu ensembles due to the presence of Pt, which favors binding and hydrogenation of C=O rather than C=C bonds.

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NSF-PAR ID:
10401134
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  
Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
ChemCatChem
Volume:
15
Issue:
5
ISSN:
1867-3880
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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