Effect of Pd Doping on the Cu0/Cu+ Ratio of Cu‐Pd/SiO2 Catalysts for Ethylene Glycol Synthesis from Dimethyl Oxalate. Issue 11 (26th July 2016)

• Record Type: Journal Article
• Authors: Zhang, Chuancai; Wang, Denghao; Zhu, Mingyuan; Yu, Feng; Dai, Bin
• Is Part Of: ChemistrySelect. Volume 1:Issue 11(2016)
• Page Start: 2857
• Page End: 2863
• Publication Date: 2016-07-26
• Subjects: Cu−Pd/SiO2 -- hydrogen spillover -- Cu/Cu+ ratio -- dimethyl oxalate -- ethylene glycol; Chemistry -- Periodicals; 540.5
• DOI: 10.1002/slct.201600570
• Languages: English
• ISSNs: 2365-6549

Abstract

Abstract: The Cu 0 /Cu + ratio is very important in many copper‐catalyzed reactions. A series of Cu−Pd/SiO2 catalysts were prepared by composite evaporation of ammonia with subsequent Pd impregnation. The Cu 0 /Cu + ratio could be controlled by changing the Pd content in the catalysts during reduction. The catalysts were applied to the hydrogenation of dimethyl oxalate, and experimental results showed that a suitable amount of Pd doping remarkably improved the activity and prolonged the lifetime of the catalyst. The optimized Cu‐0.5 % Pd/SiO2 catalyst showed complete conversion with 96.0 % ethylene glycol selectivity over a lifetime of 300 h. Enhancements in the activity and stability of the Cu−Pd/SiO2 catalysts were ascribed to the stable generation of hydrogen spillover, which tended to adjust the Cu 0 /Cu + ratio with changes in Pd content in the reduced catalysts. Hydrogen spillover also promoted the release of intermediates in contact with Cu + to inhibit copper sintering. Abstract : Cu−Pd/SiO2 shows high activity and stability for hydrogenation of dimethyl oxalate.Excellent catalytic performance is linked to the synergistic effect of Cu 0 and Cu + .H‐spillover not only improves the Cu 0 /Cu + ratio but also inhibits copper sintering. Hydrogen dissociation can be stable generated. Cu‐0.5 %Pd/SiO2 can maintain the excellent activity over a lifetime of 300 h.