Ni supported on bentonite was prepared by the impregnation method with different nickel contents, applied to the hydrogenation of nitrobenzene to aniline in a fixed-bed reactor, and it was characterized by X-ray diffraction(XRD), H_2-temperature programmed reduction(H_2-TPR), and X-ray photoelectron spectrometry(XPS). The results showed that Ni/bentonite catalyst with 20 wt% nickel content provided a higher conversion of nitrobenzene and selectivity of aniline compared to other catalysts. Ni O was the precursor of the active component of the catalyst, and the small crystallite size as well as the highly dispersed Ni O on the Ni/bentonite-20 catalyst, contributed to the catalytic performance. The hydrogenation of nitrobenzene was carried out at 300 °C with a H_2 gaseous hourly space velocity of 4800 ml·(g cat)^(-1)·h^(-1)and a nitrobenzene liquid hourly space velocity of4.8 ml·(g cat)^(-1)·h^(-1)over Ni/bentonite-20. A 95.7% nitrobenzene conversion and 98.8% aniline selectivity were obtained. While the nitrobenzene liquid hourly space velocity was 4.8 ml·(g cat)^(-1)·h^(-1), the yield of aniline was more than 95.0% during a 10-hour reaction.
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