Abstract: A process for preparing EDDN and/or EDMN by conversion of FA, HCN and EDA, the reaction being effected in the presence of water, and, after the conversion, water being depleted from the reaction mixture in a distillation column, which comprises performing the distillation in the presence of an organic solvent which has a boiling point between water and EDDN and/or EDMN at the distillation pressure existing in the column or which forms a low-boiling azeotrope with water.

Abstract: A process for reacting formaldehyde cyanohydrin (FACH) with ethylenediamine (EDA) in a reactor with limited backmixing at a temperature in the range from 20 to 120° C., wherein the residence time in the reactor is 300 seconds or less.

Abstract: A process is disclosed for separating the output from the reaction of EDDN or EDMN with hydrogen in the presence of THF, a catalyst, TETA or DETA, water, and optionally organic compounds having higher and lower boiling points than TETA or DETA. Hydrogen is removed, and the output is supplied to a distillation column DK1 in which an azeotrope, optionally comprising organic compounds with a boiling point lower than TETA or DETA, is removed from the top. A product comprising TETA or DETA is removed from the bottom and passed into a distillation column DK2, removing THF. A stream comprising TETA or DETA passes from the bottom of DK2. The DK1 azeotrope is condensed. Phase separation is induced by the addition of an organic solvent essentially immiscible with water, and the mixture is separated. The organic phase is recycled into DK1 and the water phase is discharged.

Abstract: A process for reacting ethylenediamine-formaldehyde adduct (EDFA) and/or ethylene-diamine-monoformaldehyde adduct (EDMFA) with hydrogen cyanide (HCN) in a reactor with limited backmixing at a temperature in the range from 20 to 120° C., wherein the residence time in the reactor is 300 seconds or less.

Abstract: The present invention relates to a mixture of ethylenediamine (EDA) and N-methylethylenediamine (Me-EDA) with a low content of Me-EDA, which comprises at least 99.5% by weight of ethylenediamine, and wherein the concentration of N-methylethylenediamine is in the range from 0.005 to 0.15% by weight. The present invention further relates to a process for distillative workup of a mixture comprising EDA, Me-EDA and water, by introducing the mixture into a distillation column which is operated at a column top pressure of 10 mbar to 4 bar, wherein the weight ratio of water to ethylenediamine in the mixture used is a*X:Y where X is the proportion by weight of water and Y is the proportion by weight of ethylenediamine at the azeotropic point of a binary mixture of water and ethylenediamine at the column top pressure in question, and a is a real number with a value of 0.9 or more.

Abstract: Mixtures of hydrocarbons predominantly having 4 carbon atoms per molecule known as C4 cuts are used in obtaining crude 1,3-butadiene by a thermal cracking process. Vaporous purified crude C4 cuts are produced from liquid crude C4 cuts, containing butanes, butenes, 1,3-butadiene, C3 hydrocarbons, C4 oligomers and polymers, and C5+ hydrocarbons via an extractive distillation by fist removing the C4 oligomers and polymers and the C5+ hydrocarbons and then vaporizing the liquid crude C4 cut in a vaporizer vessel. The vaporizer vessel is directly or indirectly in contact with a stripping column where liquid C4 cuts are supplied to the upper region, direct gas and liquid exchange with the vaporizer vessel occurs in the lower region, and vaporous purified crude C4 cuts are removed from the top region.

Abstract: Secondary streams in 1,3-butadiene processing plants still contain high amounts of valuable 1,3-butadiene. An energy-efficient process for purifying a recycle stream from a 1,3-butadiene processing plant is provided. The recycle stream is divided into two substreams: the first substream for prepurifying pure 1,3-butadiene feedstream by removing high boilers relative to 1,3-butadiene in a stripping column and the second substream in an extractive distillation plant.

Abstract: The invention relates to a process for preparing triethylenetetramine substituted by at least one methyl group (Me-TETA or methyl-substituted TETA compounds). Me-TETA is prepared by hydrogenating biscyanomethylimidazolidine (BCMI) in the presence of a catalyst. The present invention further relates to methyl-substituted TETA compounds as such. The present invention further relates to the use of methyl-substituted TETA compounds as a reactant or intermediate in the production of, for example, coatings or adhesives.

Abstract: Secondary streams in 1,3-butadiene processing plants still contain high amounts of valuable 1,3-butadiene. An energy-efficient process for purifying a recycle stream from a 1,3-butadiene processing plant is provided. The recycle stream is divided into two substreams: the first substream for prepurifying pure 1,3-butadiene feedstream by removing high boilers relative to 1,3-butadiene in a stripping column and the second substream in an extractive distillation plant.

Abstract: Mixtures of hydrocarbons predominantly having 4 carbon atoms per molecule known as C4 cuts are used in obtaining crude 1,3-butadiene by a thermal cracking process. Vaporous purified crude C4 cuts are produced from liquid crude C4 cuts, containing butanes, butenes, 1,3-butadiene, C3 hydrocarbons, C4 oligomers and polymers, and C5+ hydrocarbons via an extractive distillation by fist removing the C4 oligomers and polymers and the C5+ hydrocarbons and then vaporizing the liquid crude C4 cut in a vaporizer vessel. The vaporizer vessel is directly or indirectly in contact with a stripping column where liquid C4 cuts are supplied to the upper region, direct gas and liquid exchange with the vaporizer vessel occurs in the lower region, and vaporous purified crude C4 cuts are removed from the top region.

Abstract: The invention relates to a process for preparing tetraethylenepentamine (TEPA) by hydrogenation of diethylenetriaminediacetonitrile (DETDN) over a catalyst. If appropriate, DETDN can also be present as a constituent of an amino nitrile mixture which additionally comprises diethylenetriaminemonoacetonitrile (DETMN).

Abstract: The invention relates to a process for preparing formic acid by reacting carbon dioxide with hydrogen in a hydrogenation reactor in the presence of a catalyst comprising an element of group 8, 9 or 10 of the Periodic Table, a tertiary amine and a polar solvent to form formic acid-amine adducts which are subsequently dissociated thermally into formic acid and tertiary amine.

Abstract: A process for reacting formaldehyde cyanohydrin (FACH) with ethylenediamine (EDA) in a reactor with limited backmixing at a temperature in the range from 20 to 120° C., wherein the residence time in the reactor is 300 seconds or less.

Abstract: A process for preparing TETA and/or DETA by hydrogenating EDDN and/or EDMN with hydrogen in the presence of a catalyst, which comprises preparing EDDN and/or EDMN from FA, HCN and EDA in the presence of toluene as a solvent and performing the hydrogenation in suspension mode in the presence of THF.

Abstract: A process for preparing amines of the formula (II) R1—NH—CH2—CH2—NH2??(II) in which R1 is hydrogen or radicals of the formula x is integers from zero to two, by reacting nitriles of the formula (I) R2—NH—CH2—CN??(I) in which R2 is hydrogen or radicals of the formula and R3 is the NC— or H2N—CH2- radicals and x is integers from zero to two, with hydrogen in the presence of a catalyst in suspension mode or in a fixed bed, wherein the space velocity on the catalyst, based on the catalyst surface area, is 10?6 to 10?4 kg of nitrile of the formula (I) per m2 of catalyst surface area and hour, the catalyst surface area being determined by the BET method.

Abstract: A process for preparing EDDN and/or EDMN by conversion of FA, HCN and EDA, the reaction being effected in the presence of water, and, after the conversion, water being depleted from the reaction mixture in a distillation column, which comprises performing the distillation in the presence of an organic solvent which has a boiling point between water and EDDN and/or EDMN at the distillation pressure existing in the column or which forms a low-boiling azeotrope with water.

Abstract: A process is disclosed for separating the output from the reaction of EDDN or EDMN with hydrogen in the presence of THF, a catalyst, TETA or DETA, water, and optionally organic compounds having higher and lower boiling points than TETA or DETA. Hydrogen is removed, and the output is supplied to a distillation column DK1 in which an azeotrope, optionally comprising organic compounds with a boiling point lower than TETA or DETA, is removed from the top. A product comprising TETA or DETA is removed from the bottom and passed cinto a distillation column DK2, removing THF. A stream comprising TETA or DETA passes from the bottom of DK2. The DK1 azeotrope is condensed. Phase separation is induced by the addition of an organic solvent essentially immiscible with water, and the mixture is separated. The organic phase is recycled into DK1 and the water phase is discharged.

Abstract: A process for regenerating Raney catalysts by treating the catalyst with liquid ammonia with a water content of less than 5% by weight and with hydrogen having a partial pressure of 0.1 to 40 MPa in the temperature range from 50 to 350° C. for at least 0.1 hour.

Abstract: A process for reacting ethylenediamine (EDA) with formaldehyde to give ethylenediamine-formaldehyde adduct (EDFA) and/or ethylenediamine-monoformaldehyde adduct (EDMFA), which comprises performing the reaction of FA with EDA at a temperature in the range from 20 to 70° C.

Abstract: A process for preparing TETA and/or DETA by the action of EDDN and/or EDMN with hydrogen in the presence of a catalyst, wherein the catalyst used is a catalyst of the Raney type and the pressure in the course of hydrogenation is in the range from 170 to 240 bar.