Abstract: The invention relates to a process for preparing polyisocyanates by reacting primary amines with phosgene, which comprises the steps a) mixing the amine with the phosgene, b) reacting the amine with the phosgene in a residence reactor and, if desired, c) transferring the output from the reactor of step b) into a distillation column, wherein the residence reactor in step b) is configured as a tube reactor.

Abstract: An oxidation process employing a mechanically stable catalyst of an active metal or combination of active metals supported on aluminum oxide, which is predominantly alpha-aluminum oxide, is provided. The active metal or metals is optionally one or a mixture of ruthenium, copper, gold, an alkaline earth metal, an alkali metal, palladium, platinum, osmium, iridium, silver, and rhenium. The process is applicable to the oxidation of hydrogen chloride to chlorine in a Deacon process.

Abstract: A catalyst for gas-phase reactions which has high mechanical stability and comprises one or more active metals on a support comprising aluminum oxide as support material, wherein the aluminum oxide in the support consists essentially of alpha-aluminum oxide. Ruthenium, copper and/or gold are preferred as active metal. Particularly preferred catalysts according to invention comprise a) from 0.001 to 10% by weight of ruthenium, copper and/or gold, b) from 0 to 5% by weight of one or more alkaline earth metals, c) from 0 to 5% by weight of one or more alkali metals, d) from 0 to 10% by weight of one or more rare earth metals, e) from 0 to 10% by weight of one or more further metals selected from the group consisting of palladium, platinum, osmium, iridium, silver and rhenium, in each case based on the total weight of the catalyst, on the support comprising alpha-Al2O3. The catalysts are preferably used in the oxidation of hydrogen chloride (Deacon reaction).

Abstract: The invention relates to a method for delivering a short message in a mobile communications system, in which the short message sent from a mobile station is received by an SMS-Service-Centre, SMS-C, and forwarded to a corresponding recipient, wherein the SMS-C is addressed by means of an SMS-C address in the mobile communications system. The invention is distinguished by the fact that an SMS-C address recognized as erroneous is corrected on the part of the mobile communications system, and the delivery of the short message is continued with the corrected SMS-C address.

Abstract: A catalyst for gas-phase reactions which has high mechanical stability and comprises one or more active metals on a support comprising aluminum oxide as support material, wherein the aluminum oxide in the support consists essentially of alpha-aluminum oxide. Ruthenium, copper and/or gold are preferred as active metal. Particularly preferred catalysts according to invention comprise a) from 0.001 to 10% by weight of ruthenium, copper and/or gold, b) from 0 to 5% by weight of one or more alkaline earth metals, c) from 0 to 5% by weight of one or more alkali metals, d) from 0 to 10% by weight of one or more rare earth metals, e) from 0 to 10% by weight of one or more further metals selected from the group consisting of palladium, platinum, osmium, iridium, silver and rhenium, in each case based on the total weight of the catalyst, on the support comprising alpha-Al2O3. The catalysts are preferably used in the oxidation of hydrogen chloride (Deacon reaction).

Abstract: The invention relates to a process for preparing polyisocyanates by reacting organic amines with phosgene, wherein the reaction is carried out in at least three stages, with the first stage being carried out in a mixing apparatus, the second stage in at least one residence apparatus and the third stage in at least one separation apparatus and the pressure in each successive stage being lower than that in the previous stage.

Abstract: Isocyanates are prepared by reacting primary amines with phosgene in a reactor by a process in which a reaction discharge is present in the form of a suspension which contains the isocyanate to be prepared, as a liquid, and carbamyl chlorides as a solid, and the suspension is worked up in a film evaporator, and this process is carried out in a production plant.

Abstract: The invention relates to a process for the partial or complete separation of a mixture comprising hydrogen chloride and phosgene, possibly solvents and possibly low boilers and inerts as are typically obtained in the preparation of isocyanates by reaction of amines with phosgene, which comprises firstly carrying out a partial or complete condensation of phosgene, then a distillation or stripping step in a column to remove the hydrogen chloride from the bottom product phosgene and subsequently a scrub of the top product hydrogen chloride by means of the process solvent to absorb the phosgene in the process solvent. An after-purification by means of adsorption on activated carbon or by another suitable method can subsequently be carried out to remove solvent residues.

Abstract: The invention relates to a process for preparing isocyanates by reaction of amines with phosgene in the presence of inert organic solvents in a reactor and subsequent work-up of the reaction mixture leaving the reactor, wherein the solvent is separated off in a two-stage or multistage, preferably two-stage, distillation process in which the solvent is separated off at a pressure of 0.1-15 bar in a first apparatus and at 1-900 mbar in a second apparatus or further apparatuses, with the heat of condensation of the solvent vapor from the first apparatus being used for partial or complete vaporization of solvent in the second apparatus.

Abstract: A catalyst for gas-phase reactions which has high mechanical stability and comprises one or more active metals on a support comprising aluminum oxide as support material, wherein the aluminum oxide in the support consists essentially of alpha-aluminum oxide. Ruthenium, copper and/or gold are preferred as active metal. Particularly preferred catalysts according to invention comprise a) from 0.001 to 10% by weight of ruthenium, copper and/or gold, b) from 0 to 5% by weight of one or more alkaline earth metals, c) from 0 to 5% by weight of one or more alkali metals, d) from 0 to 10% by weight of one or more rare earth metals, e) from 0 to 10% by weight of one or more further metals selected from the group consisting of palladium, platinum, osmium, iridium, silver and rhenium, in each case based on the total weight of the catalyst, on the support comprising alpha-Al2O3. The catalysts are preferably used in the oxidation of hydrogen chloride (Deacon reaction).

Abstract: A process is proposed for the distillation or reactive distillation of a mixture that includes at least one toxic component, the process being carried out in a column containing a structured packing, having at least one packing layer (1) having a lower end (2) and an upper end (3), the packing layer having an internal geometry varying over its height, in such a manner that in the distillation or reactive distillation, in a first, lower region (6) of the packing layer (1) a bubbling layer having a predominantly disperse gas phase can be established and simultaneously in a second, upper region (7) of the packing layer (1) a film flow having a predominantly continuous gas phase can be established.

Abstract: A process is described for preparing diaminodiarylmethanes comprising the steps a) reacting an aromatic amine with a methylene-donating agent in the presence of homogeneous acid catalysts, b) removing the homogeneous acid catalyst from the reaction product, c) working up and purifying the reaction product, which comprises removing the homogeneous acid catalyst from the reaction mixture by adsorption to a solid adsorbent.

Abstract: The invention relates to a process for distillatively preparing TDA from a reactant stream comprising TDA, high boilers and low boilers in a dividing wall column in which a dividing wall is disposed in the longitudinal direction of the column to form an upper combined column region (2), a lower combined column region (3), a feed section (4) having a rectifying section (5) and stripping section (6), and also a withdrawal section (7) having a rectifying section (9) and stripping section (8), which comprises the following steps: a. feeding the reactant stream (13) into the feed section (4) of the dividing wall column (1); b. drawing off a low boiler fraction via the top of the column (11); c. drawing off TDA via a side draw (14) in the withdrawal section (7) of the dividing wall column (1); d. drawing off a low boiler fraction via the bottom of the column (12).

Abstract: The invention relates to a process for carrying out exothermic chemical equilibrium reactions in a fluidized-bed reactor, wherein there is a temperature distribution in the fluidized bed of the fluidized-bed reactor and the temperature difference between the lowest temperature and the highest temperature is at least 10 K. The invention further relates to a fluidized-bed reactor for carrying out chemical reactions in a fluidized bed (5), wherein at least one heat exchanger (12, 28) is located in the fluidized bed (5) to control the temperature distribution.

Abstract: The invention relates to a process for distillatively preparing TDA from a reactant stream comprising TDA, high boilers and low boilers in a dividing wall column in which a dividing wall is disposed in the longitudinal direction of the column to form an upper combined column region (2), a lower combined column region (3), a feed section (4) having a rectifying section (5) and stripping section (6), and also a withdrawal section (7) having a rectifying section (9) and stripping section (8), which comprises the following steps: a. feeding the reactant stream (13) into the feed section (4) of the dividing wall column (1); b. drawing off a low boiler fraction via the top of the column (11); c. drawing off TDA via a side draw (14) in the withdrawal section (7) of the dividing wall column (1); d. drawing off a low boiler fraction via the bottom of the column (12).

Abstract: In an aqueous formaldehyde solution comprising formaldehyde in the form of monomeric formaldehyde, methylene glycol and polyoxymethylene glycols in a total concentration x of ?65% by weight, the mean molar mass M of the polyoxymethylene glycols is, as a function of the formaldehyde concentration, equal to or less than the values given by equation I: ( M _ g ? / ? mol ) = 48 + 6.589 · 10 - 1 · ( x % ? ? by ? ? weight ) + 4.725 · 10 2 · ? ( x % ? ? by ? ? weight ) 2 - 3.434 · 10 - 3 · ( x % ? ? by ? ? weight ) 3 + ? 9.625 · 10 - 5 · ( x % ? ? by ? ? weight ) 4 - 1.172 · 10 6 · ? ( x % ? ? by ? ? weight ) 5 + 5.

Abstract: A process is described for preparing diaminodiarylmethanes comprising the steps a) reacting an aromatic amine with a methylene-donating agent in the presence of homogeneous acid catalysts, b) removing the homogeneous acid catalyst from the reaction product, c) working up and purifying the reaction product, which comprises removing the homogeneous acid catalyst from the reaction mixture by adsorption to a solid adsorbent.

Abstract: The invention relates to a process for preparing polyisocyanates by reacting organic amines with phosgene, wherein the reaction is carried out in at least three stages, with the first stage being carried out in a mixing apparatus, the second stage in at least one residence apparatus and the third stage in at least one separation apparatus and the pressure in each successive stage being lower than that in the previous stage.

Abstract: The invention relates to a process for preparing polyisocyanates by reacting primary amines with phosgene, which comprises the steps a) mixing the amine with the phosgene, b) reacting the amine with the phosgene in a residence reactor and, if desired, c) transferring the output from the reactor of step b) into a distillation column, wherein the residence reactor in step b) is configured as a tube reactor.

Abstract: The invention relates to a process for the partial or complete separation of a mixture comprising hydrogen chloride and phosgene, possibly solvents and possibly low boilers and inerts as are typically obtained in the preparation of isocyanates by reaction of amines with phosgene, which comprises firstly carrying out a partial or complete condensation of phosgene, then a distillation or stripping step in a column to remove the hydrogen chloride from the bottom product phosgene and subsequently a scrub of the top product hydrogen chloride by means of the process solvent to absorb the phosgene in the process solvent. An after-purification by means of adsorption on activated carbon or by another suitable method can subsequently be carried out to remove solvent residues.