Method for stopping a reaction during the production of aromatic amines from nitroaromatics

摘要

The present invention relates to a method for producing aromatic amines by the hydrogenation of aromatic nitro compounds. This method supplies aromatic nitro compounds and hydrogen to a reactor and contacts them with a hydrogenation catalyst; and stops the supply of aromatic nitro compounds and hydrogen to the reactor. The supply of aromatic nitro compounds and hydrogen to the reactor is stopped to ensure safe shutdown of the reactor.

主权项

1. A process for preparing aromatic amines by hydrogenation of aromatic nitro compounds, which comprises:
A) introducing aromatic nitro compounds and hydrogen into a reactor and contacting with a hydrogenation catalyst; B) stopping the introduction of aromatic nitro compounds and hydrogen into said reactor; characterized in that step B) is carried out by B1) firstly stopping the introduction of aromatic nitro compounds into said reactor so that aromatic nitro compounds present in said reactor and/or in plant parts fluidically connected upstream to said reactor react with said hydrogen which continues to be fed into said reactor, and B2) subsequently stopping the introduction of hydrogen after a predetermined time and/or after the concentration of aromatic nitro compounds in the gas stream entering the reactor falls below a predetermined value.