Selective hydrogenation of acetic acid towards acetaldehyde

Abstract

Abstract As a model reaction for the selective hydrogenation of carboxylic acids towards aldehydes, the reaction of acetic acid towards acetaldehyde has been investigated. Various oxides are used as catalysts, including platinum‐enriched oxides. It appeared that oxides with a moderate metal‐oxygen bond strength are good catalysts, provided that a source of activated hydrogen is present. On exposure to molecular hydrogen zero‐valent metals can produce activated hydrogen. Addition of precious metals, such as Pt, or completely reducing part of the oxidic catalyst can provide the zero‐valent metal. The hydrogenation probably occurs on the oxidic surface by a Mars and Van Krevelen type of mechanism.