Unprecedented Shape Selectivity in Hydrogenation of Triacylglycerol Molecules with Pt/ZSM-5 Zeolite

Dept. M2S, K.U.Leuven, Kasteelpark Arenberg 23, 3001 Heverlee, Belgium.
Angewandte Chemie International Edition (Impact Factor: 11.26). 04/2011; 50(17):3947-9. DOI: 10.1002/anie.201007513
Source: PubMed


Perfekt gestimmt: ZSM-5 mit Platinnanopartikeln bevorzugt bei der Hydrierung von Modell-Triacylglycerolen aus geometrischen Gründen die trans- gegenüber den cis-Isomeren. Der Befund, dass die zentrale Fettsäurekette schneller reagiert, deutet auf eine Adsorption in Stimmgabel-Konformation in den Poreneingängen hin (siehe Bild).

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    • "In particular shape selectivity effects have been observed in the hydrogenation of triacylglycerol molecules with Pt supported on ZSM-5 zeolite prepared by competitive ion exchange, allowing one to selectively hydrogenate the chain in the central position of the glycerol backbone due to poremouth adsorption of the tuning fork conformation [11]. "
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