Efficient NiIr alloy catalyst for selective hydrogenation of benzonitrile, crotonaldehyde and benzylideneacetone

SiO2-supported NiIr alloy acted as an effective heterogeneous catalyst for the hydrogenation of benzonitrile, crotonaldehyde and benzylideneacetone, showing much higher activity than monometallic Ni/SiO2 and Ir/SiO2 catalysts and superior selectivity to benzyl-benzylidene-amine, butanal and 4-Phenyl-butan-2-one at high conversion. Furthermore, the main active sites were investigated on the basis of the relationship of TOFs and the alloy composition for the hydrogenation of crotonaldehyde, benzonitrile and benzylideneacetone, and the active site was the isolated Ni atom surrounded by Ir atoms for the hydrogenation of crotonaldehyde and related to the structure of substrate in selective hydrogenation.