Gas Phase Hydrogenation of Furaldehydes via Coupling with Alcohol Dehydrogenation over Ceria Supported Au-Cu
AbstractWe have investigated the synthesis and application of Au-Cu/CeO2 (Cu: Au = 2) in the continuous gas phase (P = 1 atm; T = 498 K) coupled hydrogenation of 5-hydroxymethyl-2-furaldehyde (HMF) with 2-butanol dehydrogenation. STEM-EDX analysis revealed a close surface proximity of both metals in Au-Cu/CeO2 post-TPR. XPS measurements suggest (support → metal) charge transfer to form Auδ− and strong metal-support interactions to generate Cu0 and Cu+. Au-Cu/CeO2 promoted the sole formation of 2,5-dihydroxymethylfuran (DHMF) and 2-butanone in the HMF/2-butanol coupling with full hydrogen utilisation. Under the same reaction conditions, Au/CeO2 was fully selective to DHMF in standard HMF hydrogenation (using an external hydrogen supply), but delivered a lower production rate and utilised less than 0.2% of the hydrogen supplied. Exclusive -C=O hydrogenation and -OH dehydrogenation is also demonstrated for the coupling of a series of m-substituted (-CH3, -CH2CH3, -CH2OH, -CF3, -N(CH3)2, -H) furaldehydes with alcohol (1-propanol, 1-butanol, 2-propanol, 2-butanol, cyclohexanol) dehydrogenation over Au-Cu/CeO2, consistent with a nucleophilic mechanism. In each case, we observed a greater hydrogenation rate and hydrogen utilisation efficiency with a 3–15 times lower E-factor in the coupling process relative to standard hydrogenation. Our results demonstrate the feasibility of using hydrogen generated in situ through alcohol dehydrogenation for the selective hydrogenation of m-furaldehydes with important industrial applications. View Full-Text
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Pischetola, C.; Collado, L.; Keane, M.A.; Cárdenas-Lizana, F. Gas Phase Hydrogenation of Furaldehydes via Coupling with Alcohol Dehydrogenation over Ceria Supported Au-Cu. Molecules 2018, 23, 2905.
Pischetola C, Collado L, Keane MA, Cárdenas-Lizana F. Gas Phase Hydrogenation of Furaldehydes via Coupling with Alcohol Dehydrogenation over Ceria Supported Au-Cu. Molecules. 2018; 23(11):2905.Chicago/Turabian Style
Pischetola, Chiara; Collado, Laura; Keane, Mark A.; Cárdenas-Lizana, Fernando. 2018. "Gas Phase Hydrogenation of Furaldehydes via Coupling with Alcohol Dehydrogenation over Ceria Supported Au-Cu." Molecules 23, no. 11: 2905.
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