Influence of Metal Particle Size in the Hydrogenation of Citral over Ru/C

Selective hydrogenation of citral has been studied under mild conditions over Ru catalysts supported on activated carbon. Geraniol, nerol, citronellal and isopulegol were the main reac- tion products. Isopulegol is obtained by isomerization of citronellal. Small amounts of citronel- lol are formed through the hydrogenation of citronellal. The specific catalytic activity per Ru surface atom as well as the products distribution remains constant with changing metal particle size. A comparison with results obtained on the hydrogenation of cinnamaldehyde on the same Ru/ C catalysts is reported.