Résumé
Hydrogenations of acetonitrile and pentylnitrile (valeronitrile) in gas and liquid phases respectively were carried out on catalysts obtained from Ni/Mg/Al layered double hydroxides (LDHs) precursors of various Mg/Ni molar ratios. Their catalytic properties were compared with those of a commercial Ni/Al(2)O(3) catalyst. Selectivities to primary amines, higher than 90% were obtained on catalysts with Mg/Ni molar ratios in the range 0.3-1. This behaviour was correlated with the acido-basic properties of the solids characterized by TPD of NH(3) and microcalorimetry of monoethylamine adsorption. Both studies show that upon Mg addition, the surface acidity, which is responsible for secondary amine formation decreases.