Abstract: The present invention relates to a process for preparing ethylenediamine (EDA), where the process comprises the steps a) to c). In step a), formaldehyde is reacted with hydrocyanic acid (HCN) to form formaldehyde cyanohydrin (FACH), where the hydrocyanic acid is completely free or largely free of sulfur dioxide (SO2). The FACH prepared in this way is reacted with ammonia (NH3) to form aminoacetonitrile (AAN) in step b), whereupon a hydrogenation of AAN in the presence of a catalyst to form EDA is carried out in step c).

Abstract: The present invention relates to a process for purifying ethylenediamine (EDA) by distillation, wherein the process comprises the steps a) and b). In step a), a mixture (G1) comprising water, EDA and N-methylethylenediamine (N-MeEDA) is fed into a distillation apparatus (D1), and the major part of the water comprised in the mixture (G1) is separated off overhead at a pressure of greater than 4.8 bara. From the bottom of (D1), the water-enriched mixture (G2) is fed into a distillation apparatus (D2) in step b). At the top of (D2), the major part of the N-MeEDA is distilled off. The stream (S3) obtained from the bottom of (D2) comprises EDA, with the components water and N-MeEDA comprised in the mixture (G1) having been largely or completely removed. Further distillation steps can optionally be carried out in order to obtain pure EDA, for example when diethylenetriamine (DETA) is additionally comprised in the mixture (G1).

Abstract: The present invention relates to a process for purifying ethylenediamine (EDA) by distillation, wherein the process comprises the steps a) and b). In step a), a mixture (G1) comprising water, EDA and N-methylethylenediamine (N-MeEDA) is fed into a distillation apparatus (D1), and the major part of the water comprised in the mixture (G1) is separated off overhead at a pressure of greater than 4.8 bara. From the bottom of (D1), the water-enriched mixture (G2) is fed into a distillation apparatus (D2) in step b). At the top of (D2), the major part of the N-MeEDA is distilled off. The stream (S3) obtained from the bottom of (D2) comprises EDA, with the components water and N-MeEDA comprised in the mixture (G1) having been largely or completely removed. Further distillation steps can optionally be carried out in order to obtain pure EDA, for example when diethylenetriamine (DETA) is additionally comprised in the mixture (G1).

Abstract: The present invention relates to a process for preparing ethylenediamine (EDA), where the process comprises the steps a) to c). In step a), formaldehyde is reacted with hydrocyanic acid (HCN) to form formaldehyde cyanohydrin (FACH), where the hydrocyanic acid is completely free or largely free of sulfur dioxide (SO2). The FACH prepared in this way is reacted with ammonia (NH3) to form aminoacetonitrile (AAN) in step b), whereupon a hydrogenation of AAN in the presence of a catalyst to form EDA is carried out in step c).

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 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: 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 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 EDDN and/or EDMN by conversion of FA, HCN and EDA, the reaction being effected in the presence of water, wherein the reaction mixture from the conversion of EDA, HCN and FA is cooled after leaving the reactor.

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.

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 preparing EDDN and/or EDMN by a) conversion of FA, HCN and EDA, the conversion being effected in the presence of water, b) depleting water from the reaction mixture obtained in stage a), and c) treating the mixture from stage b) with an absorbent in the presence of an organic solvent, wherein the adsorbent is a solid acidic adsorbent.

Abstract: A process for preparing ethylenediaminediacetonitrile (EDDN) and/or ethylenediamine-monoacetonitrile (EDMN) by conversion of formaldehyde (FA), hydrogen cyanide (HCN) and ethylenediamine (EDA), which comprises using stabilizer-free HCN, or HCN which has been stabilized with an organic acid, in the process.