Adsorption and decomposition of isopropyl alcohol over zinc oxide. Infrared and kinetic study

Abstract

The adsorption of isopropyl alcohol and acetone on zinc oxide was studied by an infrared technique which revealed that isopropyl alcohol is dissociatively adsorbed at room temperature to form zinc alcoholate and hydroxyl group on the surface, while the adsorption of acetone takes place in its enolic form. When adsorbed isopropyl alcohol was heated to 363 K, the zinc alcoholate species changed gradually to acetone adsorbed in its enolic form, which further desorbed at higher temperatures as acetone, being replaced by the attacking isopropyl alcohol.

The behaviour of the adsorbed species during decomposition of isopropyl alcohol on zinc oxide was studied in more detail, leading to the overall reaction mechanism described by eqn (V).