The kinetics of citral hydrogenation in ethanol over an Ni/Al2O3 catalyst w
as studied in a slurry reactor operating at atmospheric pressure and at a t
emperature range of 60-77 degrees C. Citronellal was the primary reaction p
roduct, whereas the amounts of unsaturated alcohols were very minor. Citron
ellol was the dominating product, generated mainly through the hydrogenatio
n of the carbonyl group of citronellal. Based on the experimental data, a k
inetic model was developed for hydrogenation. The model comprises competiti
ve and rapid adsorption steps as well as rate-determining hydrogenation ste
ps. The mass transfer limitation of hydrogen was included in the mathematic
al model. The kinetic parameters and the mass transfer parameter of hydroge
n were estimated from the experimental data. A comparison of the model pred
ictions with the experimental data revealed that the proposed kinetic appro
ach gave a satisfactory reproduction of the data. (C) 1999 Elsevier Science
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