FIELD: organic chemistry, chemical technology. SUBSTANCE: invention relates to method for preparing aminonitrile and diamine by catalytic hydrogenation of aliphatic dinitrile, in part, to preparing 6-aminocapronitrile and hexamethylenediamine. Method involves preparing aminonitrile and diamine by catalytic hydrogenation of aliphatic dinitrile containing from 3 to 12 carbon atoms in the presence of catalyst that can be taken among Raney nickel or Raney cobalt comprising if necessary one or some promoters, for example, titanium, molybdenum, chrome, iron, tungsten, zinc, copper, silver, gold and the strong base and, possible, in the presence of a solvent. Catalyst is separated from the final reaction mass obtained by hydrogenation of dinitrile, mineral or organic acid is added in the amount corresponding to at least stoichiometric amount that is necessary for neutralization of basic mineral compounds presenting in reaction medium obtained by hydrogenation of dinitrile followed by distilling out products of reaction and unreacted dinitrile. Method allows reducing the formation of by- side products in isolation of components of reaction mixtures formed after catalytic hydrogenation of dinitriles, in part, aliphatic dinitriles. EFFECT: improved preparing method. 10 cl, 2 ex
