| The paper mainly studied the selective hydrogenation of chloronitrobenzene toprepare chloroaniline. In this paper, the Ni complexes catalysts, water-soluble nano Nicatalysts and Ni-B amorphous alloy catalysts were studied respectively. For Ni complexescatalysts, the selectivity of chloroaniline was 78.9％as the conversion of hloronitrobenzenewas 79.9％; The water-soluble nano Ni catalyst had high catalytic activity. Thehydrogenation of chloronitrobenzene catalyzed by water-soluble nano Ni catalyst could beaccomplished in a very short period of time and mild reaction conditions, and theselectivity of chloroaniline reached 97％. The Ni-B amorphous alloy catalysts were studiedespecially. The Ni-B amorphous alloy catalysts were prepared using hydrazine hydrate andpotassium borohydride as co-reducers in a mixed solvent consisting of methanol, ethanoland water in proper proportion. As can be seen from the results, the catalyst prepared bythis method showed superior catalytic properties: when the conversion ofchloronitrobenzene reached 100％, the selectivity of chloroaniline was 94.3％. The additionof certain metals to catalyst could promote the selectivity of the catalyst, and the selectivityreached 97.2％, 98.5％respectively with the addition of Cu,Fe. Moreover, the addition ofcertain metal oxides to catalytic system could inhibit the dechlorinate, whenγ-Al2O3,CaOwas added, the selectivity reached 95.9％,96.3％respectively. The inhibitor of D greatlyraised the selectivity of the reaction, the selectivity was higher than 99.8％when theinhibitor was used, and the activity of catalyst was barely affected; in addition, the ratio ofdechlorinate was not increased with the prolong of reaction time. The route of producing Band the mechanism of decreasing KBH4 inefficacy hydrolyze were proposed. Thehydrogenation mechanism of chloronitrobenzene catalyzed by the Ni-B amorphous alloycatalyst were proposed and the conclusion that dechlorinate was mainly happened after thechloroaniline was formed was further demonstrated by the reaction kinetics. The selectivityof hydrogenation of chloronitrobenzene catalyzed by Ni catalyst mainly lies in thecompetition absorption of -NO2 and -Cl on the surface of the catalyst and the soft of thecatalyst leads to the difference of the adsorption. Before the termination of the reaction, theimprovement of the Ni catalyst soft is beneficial for the increase of the selectivity.
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