A comparative study of alcohol oxidation over nanoporous gold in gas and liquid phase

Enthalten in
Journal of catalysis 
Volume
353
Start Page
99
End Page
106
Citation
Journal of Catalysis (353): 99-106 (2017)
Publisher DOI
10.1016/j.jcat.2017.07.008
Scopus ID
2-s2.0-85026501478
Publisher
Elsevier
The aerobic oxidation of methanol and ethanol in liquid phase is investigated using unsupported nanoporous gold (npAu) catalysts and compared to gas phase experiments. We pursue the question if this material is still suited as a type of model catalyst even under much more complex conditions in liquid phase. Indeed, npAu is an active catalyst for both liquid and gas phase oxidation of methanol and ethanol with O2 under mild conditions (starting at 40 °C). While in case of methanol solely the self coupling product (methyl formate) is detected, the more facile formation of the acetaldehyde in case of ethanol results in the formation of the free aldehyde (acetaldehyde) and the coupling product (ethyl acetate) in similar amounts. To further probe the surface chemistry, cross coupling reactions between both alcohols, as well as the acetaldehyde are performed. As observed also in gas phase experiments, the formation of the surface bonded aldehyde by β-H elimination of the alcoxy species is rate determining.
Schlagworte
Alcohols
Gold
Heterogeneous catalysis
Mesoporous materials
DDC Class
530: Physik
600: Technik
Projekt(e)
FOR 2213: Teilprojekt "Gefügeentwicklung und Auswirkungen der Mechanik auf die Katalyse" 
More Funding Information
Supported in the context of an Interregio Research Unit by Deutsche Forschungsgemeinschaft (DFG-FOR2213, Subprojects 2, 3 and 6).