Synthesis of Acetoaldehyde, Acetic Acid, and Others by the Dehydrogenation and Oxidation of Ethanol

Following gradual shift of primary resources from fossil towards renewable ones in chemical industry, biomass based ethanol has been attracting growing interests as a fuel to replace gasoline and as a chemical feed stock to replace ethylene. This paper reviews major work reported in the last 10 years for the production of acetaldehyde, acetic acid, and other related compounds from ethanol. At present acetic acid can be industrially produced more economically from methanol than from ethylene, the production of acetic acid from ethanol is not profitable. Acetaldehyde, which is more expensive than ethanol, can be selectively produced in gas phase by dehydrogenation over supported Cu catalysts and by oxidation with O-2 over V and Mo based oxides. It is noteworthy that gold nanoparticles deposited on basic and acidic metal oxides are highly selective to acetaldehyde by oxidation with O-2. Acetic acid can be produced in water solvent over Au catalysts supported on MgAl2O4 or on Cu doped NiO, while in gas phase over Mo-V-Nb mixed oxides combined with TiO2 colloids.