2001 Volume 69 Issue 9 Pages 699-701
A new hydrogenation system, which combined electrochemical production of atomic hydrogen with hydrogenation of unsaturated organic compounds with the atomic hydrogen, was used for the hydrogenation of crotonaldehyde, butyraldehyde and crotyl alcohol. The sole hydrogenation product of crotonaldehyde was butyraldehyde when Pd black was deposited on the substrate-side of the Pd sheet in this system. 1-Butanol and crotyl alcohol together with butyraldehyde as a main product were produced on the Pt black-loaded palladized Pd sheet. In the hydrogenation of butyraldehyde, 1-butanol was a sole hydrogenation product. On the contrary, in the hydrogenation of crotyl alcohol, not only 1-butanol as a hydrogenation product but also butyraldehyde as an isomerization product was produced. The ratio of the rate of 1-butanol production to butyraldehyde production varied with the electrolytic current for the production of atomic hydrogen and the concentration of crotyl alcohol, suggesting that the product selectivity can be strictly controlled by appropriate combination of these two factors.