Abstract: Ru-based crystalline catalysts were prepared by the impregnation method using different supports and promoters and were applied in the in-situ liquid phase catalytic hydrogenation of ortho-chloronitrobenzene (o-CNB) to ortho-chloroaniline (o-CAN). The effects of different preparation factors (including impregnation sequence, promoters, reduction temperature, supporters and promoter content) on the catalyst stability were investigated. The Ru-Fe/C catalyst was systematically characterized by transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy and N₂ adsorption-desorption with regard to physical-chemical properties such as particle size and distribution, electronic state, adsorption species, and surface parameters. The results indicated that the 0.5%Ru-15%Fe/C catalyst has higher hydrogenation activity with 99.7% o-CNB conversion and 98.7% o-CAN selectivity. The catalyst can be run for 140 h without obvious deactivation. Based on the results of characterization, the poisonous CO adsorption on catalyst surface was the main reason for deactivation, and the catalyst regeneration was studied.

Key words: ruthenium, iron oxide, in-situ liquid phase hydrogenation, ortho-chloronitrobenzene, ortho-chloroaniline, carbon monoxide