摘要:
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).
摘要:
A process for preparing a xylylenediamine by heterogeneously catalyzed hydrogenation of a phthalonitrile, wherein the hydrogenation is carried out in the presence of a cobalt skeletal catalyst, of an alkali metal hydroxide and of an alcohol and/or ether as the solvent, at an absolute pressure in the range from 1 to 100 bar and a temperature in the range from 40 to 150° C.
摘要:
A process for preparing a xylylenediamine by heterogeneously catalyzed hydrogenation of a phthalonitrile, wherein the hydrogenation is carried out in the presence of a nickel catalyst, of water, of an alkali metal hydroxide and of an ether as a solvent, at an absolute pressure in the range from 1 to 100 bar, at a temperature in the range from 40 to 150° C. and without addition of ammonia.
摘要:
The iron-containing catalyst suitable for use as a catalyst contains a) iron or a mixture containing iron and an iron-based compound. The iron has an average crystallite size ranging from 1-35 nm measured by X-ray diffraction.
摘要:
A process for reducing the level of an aliphatic monounsaturated amine (IV) in a mixture (V) containing an aminonitrile (I) or a diamine (II) or a dinitrile (III) or mixtures thereof as well as said mine (IV) by a) reacting said mixture (V) with an anionic nucleophile (VI) which contains a nucleophilic atom selected from the group consisting of oxygen, nitrogen and sulfur, which is capable of taking up an H+ ion to form an acid having a pKa value in the range from 7 to 11, as measured in water at 25° C., and which has a relative nucleophilicity, as measured in methyl perchlorate/methanol at 25° C., in the range from 3.4 to 4.7 when said nucleophilic atom is oxygen, in the range from 4.5 to 5.8 when said nucleophilic atom is nitrogen, and in the range from 5.5 to 6.8 when said nucleophilic atom is sulfur, in an amount in the range from 0.01 to 10 mol per mole of said amine (IV) in said mixture (V) at a temperature in the range from 50 to 200° C. to obtain a mixture (VII), b) distilling said aminonitrile (I) or said diamine (II) or said dinitrile (III) or mixtures thereof from said mixture (VII) at a temperature in the range from 50 to 200° C. and at a pressure in the range from 0.1 to 100 kPa to obtain a bottom product (VIII), which comprises c) distilling an aminonitrile (I) or diamine (II) or dinitrile (III) or mixtures thereof from said bottom product (VIII) at a temperature which is lower than that chosen in step b).
摘要:
A process for purifying crude caprolactam which has been obtained by 1) converting a mixture (I) comprising 6-aminocapronitrile and water to a mixture (II) comprising caprolactam, ammonia, water, high boilers and low boilers in the presence of a catalyst, then 2) removing ammonia from mixture (II) to obtain a mixture (III) comprising caprolactam, water, high boilers and low boilers, then 3) completely or partly removing water from mixture (III) to obtain crude caprolactam (IV) comprising caprolactam, high boilers and low boilers, which comprises a) feeding the crude caprolactam and an inorganic acid which has a boiling point above the boiling point of caprolactam under the distillation conditions of the following steps b) to h) to a first distillation apparatus C1, b) distilling the crude caprolactam and the inorganic acid in the first distillation apparatus C1, and removing a first substream in the bottom region and a second substream in the top region of the distillation apparatus C1, c) feeding the second substream from step b) to a second distillation apparatus C2, d) distilling the second substream from step b) in the second distillation apparatus C2, and removing a first substream in the bottom region and a second substream in the top region of the distillation apparatus C2, e) feeding the first substream from step d) to a third distillation apparatus C3, f) distilling the first substream from d) in the third distillation apparatus C3, and removing a first substream in the bottom region and purified caprolactam in the top region of distillation apparatus C3, and g) feeding the first substream from step f) to the first distillation apparatus C1.
摘要:
A process is provided for reducing the content of a monounsaturated aliphatic amine (III) in a mixture (IV) containing an aminonitrile (I) or a diamine (II), or mixtures thereof, and the amine (III), wherein a) the mixture (IV) is reacted with an anionic nucleophile (V), which contains a nucleophilic atom selected from the group comprising oxygen, nitrogen and sulfur, which is capable of taking up an H+ ion to form an acid with a pKa ranging from 7 to 11, measured in water at 25° C., and which has a relative nucleophilicity, measured in methyl perchlorate/methanol at 25° C., ranging from 3.4 to 4.7 when oxygen is the nucleophilic atom, ranging from 4.5 to 5.8 when nitrogen is the nucleophilic atom, and ranging from 5.5 to 6.8 when sulfur is the nucleophilic atom, in an amount ranging from 0.01 to 10 mol per mole of amine (III) in the mixture (IV), to give a mixture (VI), and b) the aminonitrile (I) or the diamine (II), or mixtures thereof, are distilled from the mixture (VI) at a temperature ranging from 50 to 170° C. and a pressure ranging from 0.5 to 100 kPa.
摘要:
A process for the coproduction of 6-aminocapronitrile and hexamethylenediamine starting from adiponitrile by a) hydrogenating adiponitrile in the presence of a catalyst comprising an element of the eighth transition group as catalytically active component, to obtain a mixture comprising 6-aminocapronitrile, hexamethylenediamine, adiponitrile and high boilers, b) distillatively removing hexamethylenediamine from the mixture comprising 6-aminocapronitrile, hexamethylenediamine, adiponitrile and high boilers, and either cl) distillatively removing 6-aminocapronitrile, and then d1) distillatively removing adiponitrile, or c2) simultaneously distillatively removing 6-aminocapronitrile and adiponitrile into separate fractions is characterized by base of column temperatures below 185° C. in steps d1) or c2).
摘要:
A process for removing high boilers from crude caprolactam which comprises high boilers, caprolactam and in some cases low boilers, and which has been obtained by a) reacting 6-aminocapronitrile with water to give a reaction mixture b) removing ammonia and unconverted water from the reaction mixture to obtain crude caprolactam, which comprises c) feeding the crude caprolactam to a distillation apparatus to obtain a first substream via the top as a product and a second substream via the bottom, by setting the pressure in the distillation in such a way that the bottom temperature does not go below 170° C., and adjusting the second substream in such a way that the caprolactam content of the second substream is not less than 10% by weight, based on the entire second substream.
摘要:
A process for reducing the level of an aliphatic monounsaturated amine (IV) in a mixture (V) containing an aminonitrile (I) or a diamine (II) or a dinitrile (III) or mixtures thereof as well as said amine (IV) by a) reacting said mixture (V) with an anionic nucleophile (VI) which contains a nucleophilic atom selected from the group consisting of oxygen, nitrogen and sulfur, which is capable of taking up an H+ ion to form an acid having a pKa value in the range from 7 to 11, as measured in water at 25° C., and which has a relative nucleophilicity, as measured in methyl perchlorate/methanol at 25° C., in the range from 3.4 to 4.7 when said nucleophilic atom is oxygen, in the range from 4.5 to 5.8 when said nucleophilic atom is nitrogen, and in the range from 5.5 to 6.8 when said nucleophilic atom is sulfur, in an amount in the range from 0.01 to 10 mol per mole of said amine (IV) in said mixture (V) at a temperature in the range from 50 to 200° C. to obtain a mixture (VII), b) distilling said aminonitrile (I) or said diamine (II) or said dinitrile (III) or mixtures thereof from said mixture (VII) at a temperature in the range from 50 to 200° C. and at a pressure in the range from 0.1 to 100 kPa to obtain a bottom product (VIII), which comprises c) distilling an aminonitrile (I) or diamine (II) or dinitrile (III) or mixtures thereof from said bottom product (VIII) at a temperature which is lower than that chosen in step b).