In situ electrodeposition of catalysts for the electrocatalytic hydrogenation of organic molecules—II. Hydrogenation of carbonyl compounds on nickel

✍ Scribed by M.J. Lain; D. Pletcher

• Publisher: Elsevier Science
• Year: 1987
• Tongue: English
• Weight: 468 KB
• Volume: 32
• Category: Article
• ISSN: 0013-4686
• DOI: 10.1016/0013-4686(87)87017-2

✦ Synopsis

It is shown that, using Ni on graphite or vitreous carbon cathodes formed in situ in a catholyte containing Ni'+, it is possible to convert benzaldehyde and acztophenone to a mixture of the corresponding alcohol and hydrocarbon. The selectivity to alcohol can be quite good, ea 8: 1, and the current efficiency is typically 40% (H, evolution always also occurs). In the electrolysis medium, 90% C,H,OH/lO% H,O containing 1 mol dm-" HCl and 10e2 mol dmm3 Ni'+, organic compounds inhibit strongly the nucleation and growth of Ni centres and hence it was found necessary to form the surface prior to the addition of the organic compound to the catholyte. The procedure can, however, lead to reproducible surfaces of defined structure and properties and the presence of NiZ+ in the medium can maintain the activity of the surface by continuous, low rate deposition of further Ni. The mechanisms of the hydrogenations are discussed.