Chemicals from ethanol-The ethyl acetate one-pot synthesis

The direct synthesis of ethyl acetate from ethanol, a renewable raw material, was studied using PdO/SiO2 catalysts and the oxidative route. These catalysts were prepared by ionic exchange and also by impregnation. They were characterized by XPS, UV-vis, XRD, chemical analysis and BET. These catalysts were tested under different experimental conditions using a conventional system with a fixed bed reactor at atmospheric pressure. It was inferred that the ethyl acetate synthesis occurs via ethanol oxidation followed by the condensation reaction of acetaldehyde and ethanol or ethoxide species. It can be suggested that the rate limiting step of the synthesis change according to the rate of ethanol consumption. For low rates. the limiting step is the ethanol oxidation to acetaldehyde, and for the high ones, it is the condensation reaction. It was verified that the catalysts preparation conditions modify the PdO distribution on the support and its particle sizes. therefore, changing the ethanol consumption rate. and consequently, the selectivities to acetaldehyde, ethyl acetate. acetic acid and CO2. This work shows that the ethyl acetate synthesis by the oxidative route using PdO/SiO2 catalyst can be considered as a very promising new process. (C) 2009 Elsevier B.V. All rights reserved.