Ni-b Amorphous Alloy Catalyst For Hydrogenation Of Chloroaniline The Study

The Ni-B amorphous alloy catalyst was prepared via two different chemical reduction methods, and was used in the catalytic hydrogenation of chloronitrobenzene to chloroaniline. A novel method of co-reduction with hydrazine hydrate and potassium borohydride as co-conductants was explored. The catalytic hydrogenation of o-chloronitrobenzene to o-chloroaniline through the catalyst P2 made by the new method was studied. As can be seen from the results, the conversion of o-chloronitrobenzene was 100%, the selectivity of o-chloroaniline was up to 98.20%, and the dechlorination was only 1.80%. Compared with the catalyst P1 made by the KBH4 reduction method, the catalyst P2 showed better catalytic axtivity. The catalyst was a kind of nanosized amorphous alloy as characterized by TEM, XRD and SAED. Through the hydrogenation of o-chloronitrobenzene on the different catalysts, the catalytic performance sequence of P2>P1>Raney Ni was achieved. When the catalyst P2 was used in the hydrogenation of different chloronitrobenzenes, the selectivities of chloroanilines were all over 97%, and the dechlorination less than 2%. And the mechanism of the formation of the catalyst P2 and that of the hydrogenation reaction of chloronitrobenzene to chloroaniline on it were primarily investigated as well.