Abstract: The present invention relates to a bulk material comprising solid diisocyanate, especially naphthalene 1,5-diisocyanate or p-phenylene diisocyanate, to a process for production thereof, and to a process for preparing isocyanate prepolymers using the bulk material of the invention, to the isocyanate prepolymers themselves and to the use thereof for preparation of polyurethane elastomers, especially cast polyurethane elastomers.

Abstract: The invention relates to a method for preparing a suspension of a hydrochloride of an organic amine, comprising the following steps of (i) initially charging at least one organic solvent in a reaction vessel to form a liquid level, (ii) adding hydrogen chloride, (iii) adding the organic amine, wherein the organic amine is added below the liquid level present in the reaction vessel and steps (ii) and (iii) are at least partly carried out simultaneously. Furthermore, the present invention also relates to a method wherein the suspension obtained after step (iii) is reacted in a step (iv) with phosgene to obtain the organic isocyanate corresponding to the organic amine used, to the corresponding organic isocyanate and to the use of the organic isocyanate for producing polyisocyanates.

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 invention relates to a method for producing polyisocyanates having a low monomer content, said method comprising the following steps: (i) modifying at least one monomeric diisocyanate to obtain a mixture containing at least one polyisocyanate and unconverted monomeric diisocyanate, (ii) separating the mixture obtained in step (i) into at least one gaseous stream containing monomeric diisocyanate and a liquid stream depleted of monomeric diisocyanate, (iii) partially condensing the gaseous stream from (ii) in at least one condenser, so that a liquid condensate and an uncondensed vapour stream are obtained, (iv) post-condensing the uncondensed vapour stream obtained in step (iii) in at least one post-condenser, so that a post-condensate and an uncondensed waste gas are obtained, and (v) delivering the uncondensed waste gas from step (iv) to the suction side of a vacuum pump, characterised in that the at least one post-condenser in step (iv) is operated at a post-condenser temperature, and the at least one c

Abstract: Provided is a process for separating an organic isocyanate prepared by reacting an organic amine with a stoichiometric excess of phosgene in the gas phase from the gaseous crude product obtained in the reaction, the process comprising the steps of (i) at least partially condensing the crude product stream containing at least the isocyanate, hydrogen chloride and unconverted phosgene by contacting with at least one liquid stream containing at least one quench liquid in a first separation apparatus to obtain a liquid stream containing at least some of the quench liquid and some of the isocyanate and a gas stream containing at least hydrogen chloride, evaporated quench liquid and phosgene, (ii) discharging the liquid stream obtained in step (i) via a first liquid outlet and of the gas stream obtained in (i) via a first gas conduit and (iii) at least partially condensing and/or absorbing the gas stream discharged in step (ii) through the first gas conduit, wherein that the at least partial condensation and/or abs

Abstract: Provided is a process for preparing an organic diisocyanate of the formula: OCN—R—NCO (1), wherein R represents a bivalent hydrocarbon radical containing 3 to 20 carbon atoms, the carbon atoms being arranged in a way that the two nitrogen atoms are separated from each other by at least 3 carbon atoms, the process comprising, Step (I) preparing a diurethane of the formula wherein R is the same as in formula (1), R? and R? independently represent organic radicals selected from the group consisting of 4 to 36 carbon atoms, 4 to 74 hydrogen atoms, 0 to 12 oxygen atoms that have the oxidation state ?2, and 0 to 1 halogen atoms from a diarylurethane of the formula, wherein R is the same as in formula (1), Ar and Ar? independently represent a substituted or unsubstituted aryl or heteroaryl radical selected from the group containing a total of 4 to 20 carbon atoms by transesterification, Step (II) subjecting the diurethane of the formula (2) to a cleavage reaction to form the hydroxy compounds R?—OH and R?—O

Abstract: The present invention relates to a process for preparing a polyisocyanate composition containing urethane groups, and to the polyisocyanate compositions containing urethane groups that are obtained or obtainable by this process.

Abstract: Provided is a process for separating an organic isocyanate prepared by reacting an organic amine with a stoichiometric excess of phosgene in the gas phase from the gaseous crude product obtained in the reaction, the process comprising the steps of (i) at least partially condensing the crude product stream containing at least the isocyanate, hydrogen chloride and unconverted phosgene by contacting with at least one liquid stream containing at least one quench liquid in a first separation apparatus to obtain a liquid stream containing at least some of the quench liquid and some of the isocyanate and a gas stream containing at least hydrogen chloride, evaporated quench liquid and phosgene, (ii) discharging the liquid stream obtained in step (i) via a first liquid outlet and of the gas stream obtained in (i) via a first gas conduit and (iii) at least partially condensing and/or absorbing the gas stream discharged in step (ii) through the first gas conduit, wherein that the at least partial condensation and/or abs

Abstract: The present invention relates to a bulk material comprising solid diisocyanate, especially naphthalene 1,5-diisocyanate or p-phenylene diisocyanate, to a process for production thereof, and to a process for preparing isocyanate prepolymers using the bulk material of the invention, to the isocyanate prepolymers themselves and to the use thereof for preparation of polyurethane elastomers, especially cast polyurethane elastomers.

Abstract: The invention relates to a cleaning device for separating an organic isocyanate produced by the reaction of an organic amine with a stoichiometric excess of phosgene in the gas phase from the gaseous raw product obtained in the reaction, said device comprising a first separating body comprising at least one raw product supply line for a gaseous raw product flow containing at least the isocyanate, hydrogen chloride and non-reacted phosgene, a first liquid supply line for a liquid flow containing at least one quench liquid, and a first liquid discharge line for a liquid flow containing at least part of the quench liquid and part of the isocyanate, a first gas line for transporting a gas flow containing at least hydrogen chloride, evaporated quench liquid and phosgene leading away from the first separating body.

Abstract: The invention relates to a method for recovering monomer diisocyanates, which are solid at room temperature, from a distillation residue, said method comprising the following steps: (i) preparing at least one residue which contains diisocyanates, which are solid at room temperature, and (ii) separating the residue in at least one kneader-dryer, paddle-dryer and/or roller-dryer in the presence of less than 2 wt % bitumen, based on the mass of the residue prepared in step (i), into a gaseous portion, containing monomer diisocyanate that is solid at room temperature, and a brittle residue depleted of diisocyanate, which is solid at room temperature.

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 invention relates to a method for preparing a suspension of a hydrochloride of an organic amine, comprising the following steps of (i) initially charging at least one organic solvent in a reaction vessel to form a liquid level, (ii) adding hydrogen chloride, (iii) adding the organic amine, wherein the organic amine is added below the liquid level present in the reaction vessel and steps (ii) and (iii) are at least partly carried out simultaneously. Furthermore, the present invention also relates to a method wherein the suspension obtained after step (iii) is reacted in a step (iv) with phosgene to obtain the organic isocyanate corresponding to the organic amine used, to the corresponding organic isocyanate and to the use of the organic isocyanate for producing polyisocyanates.

Abstract: The invention relates to a process for preparing at least one di- or polyformamide comprising at least two —NHCHO groups by reacting at least one primary di- or polyamine with carbon dioxide in the presence of hydrogen and at least one catalyst selected from the group consisting of heterogeneous and homogeneous catalysts or mixtures thereof. The invention further relates to a di- or polyformamide and their use for different purposes as well as a two-component-system comprising the di- or polyformamide.

Abstract: The present invention relates to a method for producing purified phosgene vapor, comprising the following steps: 1) providing a gas flow obtainable from the reaction of chlorine with carbon monoxide and comprising phosgene and carbon monoxide; 2) one-stage or multi-stage condensation of the gas flow and separation of non-condensable residue gases; 3) one-stage or multi-stage evaporation of the liquid phosgene obtained in step 2) and optional overheating of the produced phosgene vapour, wherein there is an energy integration between one or more of the condensation steps of step 2) and one or more of the evaporation steps in step 3) and the pressure in the last condensation step is between ?0.2 and ?6.0 bar higher than in the first evaporation step.

Abstract: The invention relates to a process for the preparation of aliphatic, cycloaliphatic or araliphatic isocyanates by reacting at least one primary organic amine with a stoichiometric excess of phosgene in the gas phase, comprising the steps a) reaction of the primary organic amine with an excess of phosgene in the gas phase and quenching the process product with a liquid comprising an inert aromatic solvent to obtain a liquid stream containing the isocyanate and a gas stream containing HCl and phosgene, b) separation of the gas stream containing HCl and phosgene obtained in step a) into a gas stream containing HCl and a liquid stream containing phosgene, c) partial vaporization of the liquid stream containing phosgene obtained in step b) to produce a gas stream containing phosgene, d) the gas stream containing phosgene obtained in step c) is at least partially recycled into the reaction in step a), and wherein the gas stream containing phosgene obtained in step c) contains 0.

Abstract: The present invention relates to a process for the preparation of organic diisocyanates by cleaving the corresponding diurethanes into the diisocyanate and a hydroxy compound and separating the diisocyanate from the hydroxy compound by distillation wherein the diisocyanate is obtained as the distillate.

Abstract: The present invention relates to a multistep process for the preparation of organic diisocyanates by converting the corresponding diamine precursors, urea and hydroxy compounds into monomeric diurethanes, converting these diurethanes into diurethanes of high boiling hydroxy compounds, and finally cleavage of the latter diurethanes to form the diisocyanates and recover the high boiling hydroxy compounds.

Abstract: The present invention relates to a method for producing purified phosgene vapor, comprising the following steps: 1) providing a gas flow obtainable from the reaction of chlorine with carbon monoxide and comprising phosgene and carbon monoxide; 2) one-stage or multi-stage condensation of the gas flow and separation of non-condensable residue gases; 3) one-stage or multi-stage evaporation of the liquid phosgene obtained in step 2) and optional overheating of the produced phosgene vapour, wherein there is an energy integration between one or more of the condensation steps of step 2) and one or more of the evaporation steps in step 3) and the pressure in the last condensation step is between 0.2 and 6.0 bar higher than in the first evaporation step.

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.