Copper catalysed hydrolysis of acrylonitrile to acrylamide

The effect of ethanol and dioxane as solvents for water on the hydrolysis of acrylonitrile to acrylamide in the presence of Raney copper catalysts has been investigated. Both solvents lower the rate but the reduction is somewhat greater for dioxane. The magnitude of the effect is best explained in terms of a Langmuir-Hinshelwood model in which both acrylonitrile and water are adsorbed. The added solvent inhibits reaction through competitive adsorption thus reducing the surface concentration of the two reactants. Substitution of ²H₂O changes the hydrolysis rate only slightly leading to the suggestion that the slow step is addition of water to acrylonitrile adsorbed by partial opening of the CN bond. The hydroxyimine species so formed then yields acrylonitrile by rearrangement.