Heterogeneous catalytic Wacker oxidation of ethylene over oxide-supported Pd/VOx catalysts: the support effect

Abstract

from the reacting system. In absence of any of the components no selective catalytic partial EE oxidation proceeded, indicating that the Wacker mechanism could not operate.

Elucidating the mechanism of heterogeneous Wacker oxidation over Pd-Cu/zeolite Y by transient XAS

“…Better isolation of products can be achieved by preparing the catalysts on different supports including palladium-and copper-exchanged zeolites [8][9][10][11][12][13][14][15] , palladium clusters on titania 16 , and palladium on carbon nanotubes 17 . Other chloride-free systems have been proposed, such as palladium deposited on vanadium pentoxide [18][19][20] , palladium on vanadia nanotubes 21 and palladium and manganese salts of heteropoly acids on silica 22 with different co-catalysts replacing the Cu(II)/Cu(I) redox couple. However, most of these catalyst systems either lacked sufficient activity or stability.…”

Exclusive detection of ethylene using metal oxide chemiresistors with a Pd–V2O5–TiO2 yolk–shell catalytic overlayer via heterogeneous Wacker oxidation

“…[58][59][60] Many reports have revealed that Pd doped V 2 O 5 supported on TiO 2 exhibited high catalytic activity in the vapor-phase conversion of ethylene. 36,61,62 The V 2 O 5 in the Pd-V 2 O 5 system enabled the facile re-oxidation of Pd 2+ to Pd 0 . To conrm the reducibility of the catalysts in this study, H 2 -TPR measurements were performed on the V 2 O 5 -TiO 2 and 2Pd-V 2 O 5 -TiO 2 catalysts (Fig.…”

On the Promotional and Inhibitory Effects of Water on Wacker-Type Ethylene Oxidation Over Pd–Cu/Zeolite Y

“…In propene epoxidation, water suppresses the deactivation of gold–titania while slightly diminishing the overall activity . For Wacker oxidation, water oxidizes ethylene to acetaldehyde based on isotope incorporation experiments from previous studies on both homogeneous and heterogeneous systems. − In the homogeneous Wacker system, water is used in excess as a solvent, rendering kinetic and mechanistic studies involving water challenging. The exact role of water in the heterogeneous Wacker process has not been established.…”