Direct Catalytic Conversion of Ethanol to C<sub>5+</sub> Ketones: Role of Pd–Zn Alloy on Catalytic Activity and Stability
Senthil Subramaniam, Mond Guo, Tanmayi Bathena, Michel J. Gray, Xiao Zhang, Abraham Martinez, Libor Kovařík, Konstantinos A. Goulas, Karthikeyan K. Ramasamy
Abstract
Abstract Ethanol can be used as a platform molecule for synthesizing valuable chemicals and fuel precursors. Direct synthesis of C 5+ ketones, building blocks for lubricants and hydrocarbon fuels, from ethanol was achieved over a stable Pd‐promoted ZnO‐ZrO 2 catalyst. The sequence of reaction steps involved in the C 5+ ketone formation from ethanol was determined. The key reaction steps were found to be the in situ generation of the acetone intermediate and the cross‐aldol condensation between the reaction intermediates acetaldehyde and acetone. The formation of a Pd–Zn alloy in situ was identified to be the critical factor in maintaining high yield to the C 5+ ketones and the stability of the catalyst. A yield of >70 % to C 5+ ketones was achieved over a 0.1 % Pd‐ZnO‐ZrO 2 mixed oxide catalyst, and the catalyst was demonstrated to be stable beyond 2000 hours on stream without any catalyst deactivation.