Continuous process for the hydrogenation of nitriles or nitro compounds to amines

A continuous process for the hydrogenation of compounds comprising nitrile or nitro functional groups to amine or aminonitrile compounds in the presence of a heterogeneous hydrogenation catalyst in divided form and of a basic compound said process comprising the steps of:

• a) feeding, into a stirred reactor:
• a first stream, of reactant to be hydrogenated,
• a second stream, of catalyst,
• a third stream, of basic compound, and
• a fourth stream, of hydrogen in order to maintain the reactor under a pressure of hydrogen;
• b) withdrawing, from the reactor, at least a fifth stream consisting of the reaction mixture and including hydrogen bubbles dispersed in the said mixture;
• c) making this fifth stream circulate in at least one loop, which runs into the bottom and the top of the reactor, and removing, by heat exchange with the said fifth stream, the heat produced by the hydrogenation reaction so as to maintain the reaction mixture at a temperature below 150° C.;
• d) withdrawing, from this fifth stream circulating in one of the loops, a sixth stream containing a portion of the hydrogenate separated from the catalyst;
• e) withdrawing, from the reactor or from one of the circulation loops, a seventh
• stream, of hydrogenate which is fed into a liquid/solid separation step, and
• f) recovering the liquid phase containing the catalyst-free hydrogenate and the solid phase formed by the catalyst, the said solid phase being treated in order to be regenerated before being recycled into the second catalyst stream.