INVESTIGADORES
CALAZA Florencia Carolina
artículos
Título:
Vinyl acetate formation by the reaction of ethylene with acetate species on oxygen-covered Pd(111)
Autor/es:
STACCHIOLA, DARIO J.; CALAZA, FLORENCIA C.; BURKHOLDER, LUKE; TYSOE, WILFRED T.
Revista:
JOURNAL OF THE AMERICAN CHEMICAL SOCIETY
Editorial:
AMER CHEMICAL SOC
Referencias:
Año: 2004 vol. 126 p. 15384 - 15385
ISSN:
0002-7863
Resumen:
The reaction pathway of vinyl acetate synthesis is scrutinized by reacting gas-phase ethylene (at an effective pressure of 1 ~ 10-4 Torr) with Å2-acetate species (with a coverage of 0.31 } 0.02 monolayer) on a Pd(111)−O(2~2) model catalyst surface in ultrahigh vacuum. It is found that the 1414 cm-1 infrared feature due to the symmetric OCO stretching mode of the acetate species decreases in intensity due to reaction with gas-phase ethylene, while temperature-programmed desorption experiments demonstrate that vinyl acetate is formed. The formation of ethylidyne species is detected when almost all of the acetate species have been removed. The experimental removal kinetics are reproduced by a model in which adsorbed acetates react with an ethylene-derived (possibly ethylene or vinyl) species, where ethylene adsorption is blocked by the acetate present on the surface.
