Abstract: The present invention relates to a process for distillative purification of a crude isocyanate obtained by phosgenation of the corresponding amine in a distillation apparatus under vacuum to obtain the corresponding isocyanate, characterized in that at least one liquid ring compressor is used to generate the vacuum in the distillation apparatus, a particular operating liquid is used for the at least one liquid ring compressor, the pressure p on the suction side of the at least one liquid ring compressor is 10 to 200 mbar(a), the operating temperature of the at least one liquid ring compressor is ?17° C. to +15° C.

Abstract: The present invention relates to a method and a system for separating and treating impurities from a hydrogen chloride liquid mixture from the process for preparing isocyanate with phosgenation including sending hydrogen chloride liquid mixture into a gas-liquid separation column for separation to yield a liquid phase flow with impurities at the bottom of the gas-liquid separation column, neutralizing the liquid phase flow comprising impurities with an alkaline liquid in the neutralization tank to yield a neutralized solution, and sending the neutralized solution into a waste liquid treatment device from said neutralization tank for treatment.

Abstract: Medical appliance (9, 9a, 9b, 9c) for a joint (1) of a person (10), which has at least two parts (11) which are to be placed on the joint (1) and can be moved with respect to one another by the joint (1) and at least one detection device (13) for detecting a relative movement of the parts (11), wherein the medical appliance (9, 9a, 9b, 9c) comprises an evaluation device (16), having: a determination unit (17) for determining, from detection data of the detection device (13), a range of movement (5) of the joint (1), which range of movement is actually used when the medical appliance (9, 9a, 9b, 9c) is worn, a comparison unit (18) for comparing the range of movement (5) used with a desired range of movement (6), and a support unit (19) for determining support information guiding the person (10) to the most extensive use possible of the desired range of movement (6), said support information being dependent on the result of the comparison.

Abstract: The present invention concerns a process for the preparation of pure aniline, comprising the steps of a) providing a crude aniline fraction containing up to 20.000% by weight of phenol; b) dividing the crude aniline fraction from step a) into a first partial stream and a second partial stream; c) distilling the first partial stream from step b) in a first distillation column and distilling the second partial stream from step b) in a second distillation column, wherein the first distillation column is operated at a higher head pressure than the second distillation column, with the proviso that each of the first distillation column and the second distillation column is operated at a head pressure in the range from 1.0 mbar(abs.) to 500 mbar(abs.

Abstract: The present invention concerns a process for the preparation of pure aniline, comprising the steps of a) providing a crude aniline fraction containing up to 20.000% by weight of phenol; b) dividing the crude aniline fraction from step a) into a first partial stream and a second partial stream; c) distilling the first partial stream from step b) in a first distillation column and distilling the second partial stream from step b) in a second distillation column, wherein the first distillation column is operated at a higher head pressure than the second distillation column, with the proviso that each of the first distillation column and the second distillation column is operated at a head pressure in the range from 1.0 mbar(abs.) to 500 mbar(abs.

Abstract: The present invention relates to a method and a system for separating and treating impurities from a hydrogen chloride liquid mixture, and particularly relates to a method and a system for separating and treating impurities from a hydrogen chloride liquid mixture produced from the process for preparing isocyanate with phosgenation.

Abstract: Methods for the preparation of diisocyanates by the reaction of the corresponding primary diamines with phosgene in the gas phase are described, wherein the pressure in the diamine evaporation chamber during the transfer of the diamine into the gas phase is less than the pressure in the reaction chamber during the reaction to the diisocyanates, and wherein the pressure difference between the diamine evaporation chamber and the reaction chamber prior to the mixing of diamine and phosgene is overcome by a pressure-increasing element.

Abstract: The invention relates to a method for the preparation of diisocyanates by the reaction of the corresponding primary diamines with phosgene in the gas phase, wherein the pressure in the diamine evaporation chamber during the transfer of the diamine into the gas phase is less than the pressure in the reaction chamber during the reaction to the diisocyanates, and wherein the pressure difference between the diamine evaporation chamber and the reaction chamber prior to the mixing of diamine and phosgene is overcome by a pressure-increasing element.

Abstract: The present invention relates to a process for the purification of aniline which originates from gas phase hydrogenations. In this process, only a minimum proportion of the aniline has to be evaporated and condensed again. The process is highly efficient in removing compounds which have phenolic hydroxyl groups and results in minimal losses of aniline. This process also reduces the unwanted coupling mechanisms in the division of the overall crude product in the fraction condensation into individual substreams and the subsequent workup of these.

Abstract: The present invention relates to a catalyst comprising a ceramic support with a BET surface area of less than 40 m2/g and (a) 1.0 to 100 g of at least one metal of groups 8 to 12 of the periodic table of the elements, (b) 1.0 g to 100 g of at least one metal of groups 4 to 6 and 12 of the periodic table of the elements and (c) 1.0 g to 100 g of at least one metal of groups 14 and 15 of the periodic table of the elements per liter of bulk volume of the ceramic support, wherein the catalyst is additionally doped with (d) potassium in a content of from 0.0050% by weight to 0.20% by weight, based on the total weight of the catalyst. The present invention also provides the use of such a catalyst in the catalytic gas phase hydrogenation of nitroaromatics.

Abstract: The invention relates to a process for purifying aniline produced by gas-phase hydrogenation of nitrobenzene, by fractional condensation of the crude reaction product obtained in gaseous form so that at least two liquid process products, a partial condensate (PK) and a total condensate (TK), are obtained.

Abstract: The invention relates to a process for the continuous preparation of aromatic amines by hydrogenation of the corresponding nitroaromatics in the presence of catalysts arranged in reaction spaces, in which an adiabatically operated reaction space RA is connected downstream of an isothermally operated reaction space RI and RA additionally also has a separate feed for the nitroaromatic to be hydrogenated, RI is fed with the nitroaromatic to be hydrogenated from the start to the end of the hydrogenation, and the product mixture emerging from RI is fed into RA from the start to the end of the hydrogenation, wherein RA can additionally be fed via the separate feed with the nitroaromatic to be hydrogenated.

Abstract: Aromatic amines are produced by adiabatic hydrogenation of nitroaromatic compounds in the gas phase on one or more fixed catalysts. The nitroaromatic reactant is passed over the catalyst under pressure and at elevated temperature with hydrogen, water, optionally nitrogen and substantially in the absence of the aromatic amine produced from the nitroaromatic.

Abstract: The present invention relates to a process for the purification of aniline which originates from gas phase hydrogenations. In this process, only a minimum proportion of the aniline has to be evaporated and condensed again. The process is highly efficient in removing compounds which have phenolic hydroxyl groups and results in minimal losses of aniline. This process also reduces the unwanted coupling mechanisms in the division of the overall crude product in the fraction condensation into individual substreams and the subsequent workup of these.

Abstract: The present invention relates to a catalyst comprising a ceramic support with a BET surface area of less than 40 m2/g and (a) 1.0 to 100 g of at least one metal of groups 8 to 12 of the periodic table of the elements, (b) 1.0 g to 100 g of at least one metal of groups 4 to 6 and 12 of the periodic table of the elements and (c) 1.0 g to 100 g of at least one metal of groups 14 and 15 of the periodic table of the elements per litre of bulk volume of the ceramic support, wherein the catalyst is additionally doped with (d) potassium in a content of from 0.0050% by weight to 0.20% by weight, based on the total weight of the catalyst. The present invention also provides the use of such a catalyst in the catalytic gas phase hydrogenation of nitroaromatics.

Abstract: The invention relates to a process for the preparation of isocyanates in a system network comprising an isocyanate production plant, a chlorine production plant and a phosgene production plant, in which carbon dioxide formed as a by-product is partially to completely condensed out with the gaseous chlorine formed in the chlorine production plant and enters into the phosgene preparation process and, after the preparation of phosgene, the predominant part of the carbon dioxide formed is thereby sluiced out of the system network in gaseous form.

Abstract: The invention relates to a process for the continuous preparation of aromatic amines by hydrogenation of the corresponding nitroaromatics in the presence of catalysts arranged in reaction spaces, in which an adiabatically operated reaction space RA is connected downstream of an isothermally operated reaction space RI and RA additionally also has a separate feed for the nitroaromatic to be hydrogenated, RI is fed with the nitroaromatic to be hydrogenated from the start to the end of the hydrogenation, and the product mixture emerging from RI is fed into RA from the start to the end of the hydrogenation, wherein RA can additionally be fed via the separate feed with the nitroaromatic to be hydrogenated.

Abstract: The invention relates to a process for purifying aniline produced by gas-phase hydrogenation of nitrobenzene, by fractional condensation of the crude reaction product obtained in gaseous form so that at least two liquid process products, a partial condensate (PK) and a total condensate (TK), are obtained, wherein the condensation leading to the formation of PK is carried out at higher temperature than the temperature leading to the formation of TK, a product stream originating from PK and a product stream originating from TK are each passed separately from one another into a distillation column consisting of at least one stripping section and at least one rectifying section, wherein the product stream originating from PK is introduced into the lower section of the distillation column between the lowermost stripping section and the section which follows, and the product stream originating from TK is introduced into the top of the distillation column above the uppermost rectifying section, and the desired purif

Abstract: The present invention relates to a process for simplified separation of a reaction product (P) from reaction gas mixtures by means of partial condensation of the reaction gas mixture consisting of the reaction product (P), at least one high boiler (H) and at least one low boiler (L).

Abstract: The present invention relates to a continuous process for the production of nitrobenzene by nitration of benzene with nitric acid or mixtures of nitric acid and sulfuric acid to give a crude nitrobenzene, washing of the crude nitrobenzene by means of at least one of each of an acid, alkaline and neutral washing, there being obtained a pre-purified nitrobenzene which, as well as containing nitrobenzene, at least contains also low boilers, optionally middle boilers as well as high boilers and salts, wherein the pre-purified nitrobenzene is purified further by separating off low boilers in a distillation apparatus by evaporation of the low boilers, and separation of nitrobenzene from the resulting further purified nitrobenzene in a distillation apparatus by partial evaporation of nitrobenzene, wherein pure nitrobenzene is removed from the distillation apparatus in gaseous form and is subsequently condensed, and wherein the non-evaporated portion of the further purified nitrobenzene is fed back into the washing a