Patent ID: 7626057

Claim:
A method of producing xylylenediamine by a two-stage hydrogenation of a starting phthalonitrile in a solvent, which comprises: (1) a hydrogenation step 1 in which a 1 to 20% by weight solution of the starting phthalonitrile in the solvent containing liquid ammonia is fed to an inlet of a first reaction zone and the hydrogenation is carried out in the first reaction zone in the presence of a heterogeneous catalyst so as to convert 60 to 98% of a total nitrile groups in the starting phthalonitrile to aminomethyl groups, thereby obtaining a first hydrogenation product solution, (2) a hydrogenation step 2 in which the first hydrogenation product solution undergoes the hydrogenation in a second reaction zone in the presence of a heterogeneous catalyst, thereby obtaining a second hydrogenation product solution in which a content of cyanobenzylamine is 0.2% by weight or less of xylylenediamine, and (3) a step in which the second hydrogenation product solution is distilled to remove the solvent and a crude product thus obtained is distilled, thereby obtaining a purified xylylenediamine, provided that 30 to 90% by weight of the first hydrogenation product solution discharged from the first reaction zone is circulated to the inlet of the first reaction zone and a rest thereof is introduced to the second reaction zone.