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). If ammonia is additionally comprised in the mixture (G1), an ammonia removal is preferably additionally carried out before carrying out the step a) in the process of the invention.

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). If ammonia is additionally comprised in the mixture (G1), an ammonia removal is preferably additionally carried out before carrying out the step a) in the process of the invention.

A process for the manufacture of ethyleneamines and ethanolamines, comprising the steps of (i) converting a glycolaldehyde derivative of formula (II), in which R.sup.2, R.sup.3 are—the same or different—hydrogen, alkyl, such as C.sub.1-6-alkyl, or cycloalkyl such as Cs-e-cycloalkyl; and an animating agent of formula (III); in which R1 is hydrogen (H), alkyl, such as C.sub.1-6-alkyl, or cycloalkyl such as C.sub.3-6-cycloalkyl, in the gas or liquid phase; (ii) feeding the reaction products obtained in step (i) into a hydrogenation reactor, where the reaction products are converted with hydrogen in the presence of a hydrogenation catalyst.

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The present invention relates to a process for purifying ethylenediamine, in which a) a mixture comprising water (H2O), ethylenediamine (EDA) and N-methylethylenediamine (NMEDA) is introduced into a rectification column (NMEDA removal column), where the mixture introduced comprises at least the amount of water as required for the formation of a high-boiling azeotrope of EDA and water at the appropriate bottom temperature; and the EDA-comprising bottom product from the NMEDA removal column is introduced into a second rectification column (EDA dewatering column), wherein the pressure at the top of the EDA dewatering column is adjusted such that the boiling temperature of the mixture obtained at the top is 10° C. or higher than the bottom temperature of the NMEDA removal column, which comprises (i) partly or fully condensing the vapors from the top of the EDA dewatering column in a condenser which is cooled with a medium which is at least partly evaporated during the condensation and the vapor thus formed is used at least partly to heat the evaporator of the NMEDA removal column; and/or (ii) introducing the vapors from the top of the EDA dewatering column into the NMEDA removal column.

The present invention relates to a process for purifying ethylenediamine, in which a) a mixture comprising water (H2O), ethylenediamine (EDA) and N-methylethylenediamine (NMEDA) is introduced into a rectification column (NMEDA removal column), where the mixture introduced comprises at least the amount of water as required for the formation of a high-boiling azeotrope of EDA and water at the appropriate bottom temperature; and the EDA-comprising bottom product from the NMEDA removal column is introduced into a second rectification column (EDA dewatering column), wherein the pressure at the top of the EDA dewatering column is adjusted such that the boiling temperature of the mixture obtained at the top is 10° C. or higher than the bottom temperature of the NMEDA removal column, which comprises (i) partly or fully condensing the vapors from the top of the EDA dewatering column in a condenser which is cooled with a medium which is at least partly evaporated during the condensation and the vapor thus formed is used at least partly to heat the evaporator of the NMEDA removal column; and/or (ii) introducing the vapors from the top of the EDA dewatering column into the NMEDA removal column.

The present invention relates to a process for purifying ethylenediamine, in which a) a mixture comprising water (H2O), ethylenediamine (EDA) and N-methylethylenediamine (NMEDA) is introduced into a rectification column (NMEDA removal column), where the mixture introduced comprises at least the amount of water as required for the formation of a high-boiling azeotrope of EDA and water at the appropriate bottom temperature; and the EDA-comprising bottom product from the NMEDA removal column is introduced into a second rectification column (EDA dewatering column), wherein the pressure at the top of the EDA dewatering column is adjusted such that the boiling temperature of the mixture obtained at the top is 10° C. or higher than the bottom temperature of the NMEDA removal column, which comprises (i) partly or fully condensing the vapors from the top of the EDA dewatering column in a condenser which is cooled with a medium which is at least partly evaporated during the condensation and the vapor thus formed is used at least partly to heat the evaporator of the NMEDA removal column; and/or (ii) introducing the vapors from the top of the EDA dewatering column into the NMEDA removal column.

The present invention describes a new crystalline form of triethylenetetramine tetrachloride which has improved room temperature stability over known forms and over the dichloride salt. The new crystalline form is characterised by having peaks in an XRPD spectrum at 22.9, 25.4, 25.8, 26.6, 34.6 and 35.3±0.1° 2θ and Raman shifts 943, 1173, 1527 and 1612±5 cm.sup.−1. The crystalline form of triethylenetetramine tetrachloride is useful in the treatment of Wilson's disease.

The present invention describes a new crystalline form of triethylenetetramine tetrachloride which has improved room temperature stability over known forms and over the dichloride salt. The new crystalline form is characterised by having peaks in an XRPD spectrum at 22.9, 25.4, 25.8, 26.6, 34.6 and 35.3±0.1° 2θ and Raman shifts 943, 1173, 1527 and 1612±5 cm.sup.−1. The crystalline form of triethylenetetramine tetrachloride is useful in the treatment of Wilson's disease.

The present invention relates to a process for purifying a mixture comprising MEG, MEA, EDA and DETA, and low boilers having a boiling point not higher than PIP and high boilers having a boiling point not lower than AEEA, wherein the process comprises the following steps: a) separating a mixture comprising MEG, MEA, EDA and DETA, and low boilers having a boiling point not higher than PIP and high boilers having a boiling point not lower than AEEA, into (i) a mixture A comprising EDA and the low boilers having a boiling point not higher than PIP; and (ii) a mixture B comprising MEA; and (iii) a mixture C comprising MEG, DETA and the high boilers having a boiling point not lower than AEEA; b) separating mixture C from stage a) into (i) a mixture D comprising MEG; and (ii) a mixture E comprising MEG, DETA and the high boilers having a boiling point not lower than AEEA; c) separating mixture E from stage b) either into (i) a mixture F comprising MEG and DETA; and (ii) a mixture G comprising the high boilers having a boiling point not lower than AEEA; or into (i) a mixture F comprising MEG and DETA; and (ii) a mixture G1 comprising AEEA; and (iii) a mixture G2 comprising the high boilers having a boiling point higher than AEEA; d) separating mixture F from stage c) by extractive distillation with triethylene glycol into (i) a mixture H comprising MEG; and (ii) a mixture I comprising DETA and TEG.

The present invention relates to a process for purifying a mixture comprising MEG, MEA, EDA and DETA, and low boilers having a boiling point not higher than PIP and high boilers having a boiling point not lower than AEEA, wherein the process comprises the following steps: a) separating a mixture comprising MEG, MEA, EDA and DETA, and low boilers having a boiling point not higher than PIP and high boilers having a boiling point not lower than AEEA, into (i) a mixture A comprising EDA and the low boilers having a boiling point not higher than PIP; and (ii) a mixture B comprising MEA; and (iii) a mixture C comprising MEG, DETA and the high boilers having a boiling point not lower than AEEA; b) separating mixture C from stage a) into (i) a mixture D comprising MEG; and (ii) a mixture E comprising MEG, DETA and the high boilers having a boiling point not lower than AEEA; c) separating mixture E from stage b) either into (i) a mixture F comprising MEG and DETA; and (ii) a mixture G comprising the high boilers having a boiling point not lower than AEEA; or into (i) a mixture F comprising MEG and DETA; and (ii) a mixture G1 comprising AEEA; and (iii) a mixture G2 comprising the high boilers having a boiling point higher than AEEA; d) separating mixture F from stage c) by extractive distillation with triethylene glycol into (i) a mixture H comprising MEG; and (ii) a mixture I comprising DETA and TEG.