Hydrogenation of carbon-carbon multiple bonds: chemo-, regio- and stereo-selectivity

Results of the last decade with respect to the selective hydrogenation of h ydrocarbons with multiple unsaturation (dienes and alkynes) over heterogene ous palladium catalysts are reviewed. Factors such as metal dispersion, car bon deposits, and the use of promoters and additives controlling catalytic activities and chemo-, regio- and stereo-selectivity are discussed. A detai led treatment of the status of the selective removal of hydrocarbon impurit ies with multiple unsaturation from industrial feedstocks is also given. (C ) 2001 Elsevier Science B.V. All rights reserved.