Nitrobenzene hydrogenation over nano-sized Pd on γ-Al2O3 catalyst

Aniline was synthesized by catalytic hydrogenation of nitrobenzene (NB) on nano-sized Pd on γ-Al2O3 catalyst prepared by sol-gel method. The catalyst was characterized by SEM and XRD. The average particle of Pd catalyst was 36 nm. In hydrogenation reaction of nitrobenzene, the hydrogenation rate was zero-order with respect to nitrobenzene and increased with increasing of hydrogen pressure. Compared with commercial Pd/γ-Al2O3, catalytic activity and selectivity of the as-prepared Pd/γ-Al2O3 is superior. The reason proposed for higher catalytic activity of nano-sized Pd is the small particle size and highdensity surface defects.