Process for the hydrogenation of MDA

Process for the continuous heterogeneous catalytic hydrogenation of MDA, characterized in that

• a) the process is carried out in a reactor cascade comprising n serially connected reaction spaces that are each filled with catalyst and can be filled or emptied independently of one another, which are respectively given the designation Ri, where 1≤i≤n, in the order in which they are connected,
• b) and R1 is temporarily disconnected from the cascade as soon as the catalyst present in R1 has in the course of the reaction become deactivated to an undesirable degree,
• resulting in a reconfigured reactor cascade comprising i′ reaction spaces, which are given the designation Ri′, where 1≤i′≤(n−1), in the order in which they are connected,
• wherein each reaction space Ri where 2≤i≤n becomes a reaction space Ri′ where 1≤i′≤(n−1),
• c) the catalyst in R1 is replaced and/or regenerated and
• d) R1 is subsequently connected as reaction space Ri′ where i′=n.