Selective hydrogenation of ethyl benzoate over Ni–B amorphous alloys supported on γ-Al₂O₃

Abstract

A series of Ni–B amorphous alloys supported on γ-Al₂O₃ was prepared by an impregnation chemical reduction method and tested in the selective hydrogenation of ethyl benzoate to ethyl cyclohexane carboxylate. The effect of different metal additives on the activity of the supported Ni–B amorphous alloys was investigated. It was found that the addition of small amounts of Pd to Ni–B amorphous alloy supported on γ-Al₂O₃ could markedly improve its activity and the yield of ethyl cyclohexane carboxylate can reach 88.1 % under the optimal reaction conditions. Furthermore, this catalyst could be recycled eight times without appreciable loss of its initial activity, much better than the unsupported one. The Ni–Pd–B amorphous alloy was proven to be highly dispersed on the surface and in the pores of γ-Al₂O₃, resulting in its larger BET area, more active Ni species, better stability, and hence accounting for its good catalytic performance.