The gas phase (1 atm, 473 -563 K) hydrogenation of butyronitrile has been studied over Pd/SiO 2 and Ba -Pd/SiO 2 . Catalysts characterization involved temperature-programmed reduction (TPR), H 2 /NH 3 chemisorption/temperature programmed desorption (TPD), X-ray diffraction (XRD), and TEM measurements. The incorporation of Ba with Pd resulted in the formation of smaller metal nano-particles (7 vs 28 nm) with a resultant (seven-fold) higher H 2 chemisorption and decreased total surface acidity (from NH 3 chemisorption/TPD).Temperature-related activity maxima were observed for both catalysts and are associated with thermal desorption of the nitrile reactant. Exclusivity to the target butylamine was achieved at T $ 543 K where Ba -Pd/SiO 2 delivered higher selective hydrogenation rate (91 mol h 21 mol Pd
21) than Pd/SiO 2 (54 mol h 21 mol Pd 21 ), attributed to greater availability of surface-reactive hydrogen. Lower surface acidity served to minimize condensation to higher amines. The rate and selectivity to butylamine exceed those previously reported for gas phase operation.