Abstract: The invention relates to a process for obtaining at least one aromatic amine from a liquid mixture comprising water and the at least one aromatic amine by extracting with at least one nitroaromatic in an extraction column (1) to form an essentially water-comprising raffinate stream and an extract stream comprising the at least one nitroaromatic and the aromatic amine. The extraction column (1) is divided by a dividing wall (3) into two regions (5, 7), and, in the case of an amount of liquid for separation which is less than a minimum cross sectional loading of the entire extraction column (1), the liquid mixture to be separated is fed only to one of the regions (5, 7) of the extraction column (1) divided by the dividing wall (3). The invention further relates to a process for preparing an aromatic amine and to an apparatus for separating a liquid mixture comprising water and at least one aromatic amine by extracting with at least one nitroaromatic, comprising an extraction column (1).

Abstract: The invention relates to a process for obtaining at least one aromatic amine from a liquid mixture comprising water and the at least one aromatic amine by extracting with at least one nitroaromatic in an extraction column (1) to form an essentially water-comprising raffinate stream and an extract stream comprising the at least one nitroaromatic and the aromatic amine. The extraction column (1) is divided by a dividing wall (3) into two regions (5, 7), and, in the case of an amount of liquid for separation which is less than a minimum cross sectional loading of the entire extraction column (1), the liquid mixture to be separated is fed only to one of the regions (5, 7) of the extraction column (1) divided by the dividing wall (3). The invention further relates to a process for preparing an aromatic amine and to an apparatus for separating a liquid mixture comprising water and at least one aromatic amine by extracting with at least one nitroaromatic, comprising an extraction column (1).

Abstract: The invention relates to a process for obtaining at least one aromatic amine from a liquid mixture comprising water and the at least one aromatic amine by extracting with at least one nitroaromatic in an extraction column (1) to form an essentially water- comprising raffinate stream and an extract stream comprising the at least one nitroaromatic and the aromatic amine. The extraction column (1) is divided by a dividing wall (3) into two regions (5, 7), and, in the case of an amount of liquid for separation which is less than a minimum cross sectional loading of the entire extraction column (1), the liquid mixture to be separated is fed only to one of the regions (5, 7) of the extraction column (1) divided by the dividing wall (3). The invention further relates to a process for preparing an aromatic amine and to an apparatus for separating a liquid mixture comprising water and at least one aromatic amine by extracting with at least one nitroaromatic, comprising an extraction column (1).

Abstract: What is proposed is a process for preparation and distillative workup of diphenylmethane diisocyanate (MDI), proceeding from a benzene-comprising feedstream, in which, in a catalytic hydrogenation of nitrobenzene to aniline, steam is raised at two different pressure levels, which partly or completely covers the energy demand for the overall process, by using two fluidized bed reactors of identical design, of which a first fluidized bed reactor is operated with an aniline load for which the fluidized bed reactors have been designed and provides steam at a first, lower pressure level, and a second fluidized bed reactor is operated with a load lowered with respect to the first fluidized bed reactor to such an extent that the second fluidized bed reactor affords steam at the higher pressure level.

Abstract: The invention relates to a process for working up wastewaters which are obtained in the purification of crude aromatic nitro compounds after the nitration of aromatic compounds, comprising the following steps: (a) single-stage or multistage washing of the crude aromatic nitro compound to obtain at least one organic phase and at least one aqueous phase, and removal of the aqueous phase or of the aqueous phases, step (a) comprising the addition of a base other than ammonia, and then (b) optional removal of organic constituents from at least a portion of the aqueous phase or aqueous phases obtained in step (a) by stripping, preferably with steam, then (c) removal of organic compounds from at least a portion of the aqueous phase or aqueous phases resulting from step (a) or step (b) by thermal and/or oxidative degradation, then (d) distillative depletion of ammonia from at least a portion of the aqueous phase or aqueous phases resulting from step (c), and then (e) optional supply of at least a portion of the aq

Abstract: What is proposed is a process for preparation and distillative workup of diphenylmethane diisocyanate (MDI), proceeding from a benzene-comprising feedstream, in which, in a catalytic hydrogenation of nitrobenzene to aniline, steam is raised at two different pressure levels, which partly or completely covers the energy demand for the overall process, by using two fluidized bed reactors of identical design, of which a first fluidized bed reactor is operated with an aniline load for which the fluidized bed reactors have been designed and provides steam at a first, lower pressure level, and a second fluidized bed reactor is operated with a load lowered with respect to the first fluidized bed reactor to such an extent that the second fluidized bed reactor affords steam at the higher pressure level.

Abstract: The invention relates to a process for obtaining at least one aromatic amine from a liquid mixture comprising water and the at least one aromatic amine by extracting with at least one nitroaromatic in an extraction column (1) to form an essentially water-comprising raffinate stream and an extract stream comprising the at least one nitroaromatic and the aromatic amine. The extraction column (1) is divided by a dividing wall (3) into two regions (5, 7), and, in the case of an amount of liquid for separation which is less than a minimum cross sectional loading of the entire extraction column (1), the liquid mixture to be separated is fed only to one of the regions (5, 7) of the extraction column (1) divided by the dividing wall (3). The invention further relates to a process for preparing an aromatic amine and to an apparatus for separating a liquid mixture comprising water and at least one aromatic amine by extracting with at least one nitroaromatic, comprising an extraction column (1).