Abstract: The present invention relates to a method for treating a substance mixture comprising an aromatic amine, wherein the aromatic amine is aniline or 2,4-diaminotoluene, preferably aniline. The substance mixture comprises an aromatic amine and compounds having a higher boiling point than the aromatic amine. The method for treating the substance mixture requires I) separating the first substance mixture by means of distillation in a first distillation unit (110, 1130), to at least partially remove some of the aromatic amine in the process, and to obtain a first bottom product which is removed from the first distillation unit (110, 1130). After removal from the first distillation unit (110, 1130), the bottom product is diluted with a condensed top product from a distillation unit that is different from the first distillation unit and/or with a composition that comprises methanol.

Abstract: 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.

Abstract: The present invention relates to a method of producing aromatic amines by hydrogenation of aromatic nitro compounds. This method provides a reactor containing a hydrogenation catalyst; supplies aromatic nitro compounds and hydrogen to the reactor and contacts them with a hydrogenation catalyst, in which the hydrogen which is supplied to the reactor is by a compressor and the compressor contains an operating fluid which at least partially contacts the hydrogen; and regenerates the hydrogenation catalyst by heating and contacting it with oxygen. Particular operating liquids are subsequently exchanged.

Abstract: The present invention relates to a method for treating a substance mixture comprising an aromatic amine, wherein the aromatic amine is aniline or 2,4-diaminotoluene, preferably aniline. The substance mixture comprises an aromatic amine and compounds having a higher boiling point than the aromatic amine. The method for treating the substance mixture requires I) separating the first substance mixture by means of distillation in a first distillation unit (110, 1130), to at least partially remove some of the aromatic amine in the process, and to obtain a first bottom product which is removed from the first distillation unit (110, 1130). After removal from the first distillation unit (110, 1130), the bottom product is diluted with a condensed top product from a distillation unit that is different from the first distillation unit and/or with a composition that comprises methanol.

Abstract: The present invention relates to A method for producing aromatic amines by the hydrogenation of aromatic nitro compounds. This method comprises: A) supplying aromatic nitro compounds and hydrogen to a reactor and contacting them with a hydrogenation catalyst; and B) stopping the supply of aromatic nitro compounds and hydrogen to the reactor. In addition, B) is carried out by: B1) stopping the supply of aromatic nitro compounds to the reactor such that any remaining aromatic nitro compounds present in the reactor and/or in parts of the installation that are fluidically connected to the reactor upstream react with the hydrogen that is still being supplied to the reactor, and B2) stopping the supply of hydrogen after a predetermined time interval and/or after the concentration of aromatic nitro compounds in the gas flow entering the reactor falls below a predetermined value.

Abstract: The present invention relates to a method of producing aromatic amines by hydrogenation of aromatic nitro compounds. This method comprises the steps: A) making a reactor containing a hydrogenation catalyst available; B) supplying aromatic nitro compounds and hydrogen to the reactor and contacting them with a hydrogenation catalyst, with at least the hydrogen which is supplied to the reactor is by means of a compressor and the compressor contains an operating fluid which at least partially contacts the hydrogen; and C) regenerating the hydrogenation catalyst by heating and contacting it with oxygen. After step C), steps D1) and/or D2) are carried out. Step D1) removes at least some of any fluids that are present in the reactor and/or in parts of the installation which are fluidically connected to the reactor downstream, with the fluids having been at least partially present in the reactor and/or in these parts of the installation during C).