摘要:
A process for the preparation of caprolactam is provided, wherein a) a mixture (I) containing 6-aminocapronitrile and water is reacted in the gas phase, in the presence of a catalyst, to give a mixture (II) containing caprolactam, ammonia, water, high-boiling components and low-boiling components, b) ammonia is then removed from the mixture (II) to give a mixture (III) containing caprolactam, water, high-boiling components and low-boiling components, c) water is then removed from the mixture (III) to give a mixture (IV) containing caprolactam, high-boiling components and low-boiling components, and d) a solid (V) containing caprolactam is then obtained from the mixture (IV) by crystallization, the proportion by weight of caprolactam in the solid (V) being greater than in the mixture (IV).
摘要:
A process for the preparation of caprolactam is provided, wherein a) a mixture (I) containing 6-aminocapronitrile and water is reacted in the liquid phase, in the presence of a catalyst, to give a mixture (II) containing caprolactam, ammonia, water, high-boiling components and low-boiling components, b) ammonia is then removed from the mixture (II) to give a mixture (III) containing caprolactam, water, high-boiling components and low-boiling components, c) water is then removed from the mixture (III) to give a mixture (IV) containing caprolactam, high-boiling components and low-boiling components, and d) a solid (V) containing caprolactam is then obtained from the mixture (IV) by crystallization, the proportion by weight of caprolactam in the solid (V) being greater than in the mixture (IV).
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 distillative removal of ammonia from solutions (I) which include a lactam and ammonia comprises effecting said removal in a distillation apparatus (a) at an absolute pressure of less than 10 bar.
摘要:
The invention relates to a method for removing, by distillation, 6-aminocapronitrile from mixtures that contain 6-aminocapronitrile, adipodinitrile and hexamethylenediamine, by a) removing the hexamethylenediamine from the mixture while obtaining a mixture (I) that has a hexamethylenediamine content of less than 1 wt. -%, b) removing completely or partially the 6-aminocapronitrile from mixture (I) while obtaining a mixture (II) whose content in substances that have a higher boiling point as 6-aminocapronitrile under distillation conditions and that cannot be formed by dimerization reactions when 6-aminocapronitrile is thermally treated is less than 1 wt. -%, and c) completely or partially removing from mixture (II) the hexamethylenediamine that might be present while obtaining a mixture (IV) whose hexamethylenediamine content is higher than that of mixture (II), and a mixture (V) whose hexamethylenediamine content is lower than that of mixture (II).
摘要:
A process is provided for the regeneration of a heterogeneous catalyst used for the preparation of compounds containing NH2 groups by the hydrogenation, with hydrogen, of compounds containing at least one unsaturated carbon-nitrogen bond, wherein a) the feed of the compound to be hydrogenated is stopped and b) the heterogeneous catalyst is treated with a compound of the formula R1R2N—CO—R3 (I), in which R1 is hydrogen or C1-C4 alkyl and R2, R3 independently of one another are each hydrogen or C1-C4 alkyl or together are a C3-C6 alkylene group, or mixtures of such compounds, at a pressure ranging from 0.1 to 30 MPa and a temperature ranging from 100 to 300° C., with the proviso that the compound of formula (I) is in liquid form during the treatment.
摘要:
A process for preparing a polymer, which comprises a) reacting a mixture (I) containing 6-aminocapronitrile and water in the presence of a catalyst to obtain a mixture (II) containing caprolactam, ammonia, water, high boilers and low boilers, then b) removing ammonia from mixture (II) to obtain a mixture (III) containing caprolactam, water, high boilers and low boilers, then c) removing all or some of the water from mixture (III) to obtain a mixture (IV) containing caprolactam, high boilers and low boilers and then d) feeding mixture (IV) to a polymerization reaction, and also the polymer obtainable by this process, the use of the polymer for producing fibers, sheetlike structures and moldings, and also fibers, sheetlike structures and moldings obtainable using such a polymer.
摘要:
The invention relates to a method for producing cyclic lactams of formula (II) by reacting a compound (I) of formula (I) with water in the presence of an organic, liquid dilution agent in the liquid phase. In formula (II), n and m respectively can have the values 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 and the sum of n+m is at least 3, preferably at least 4 and R1 and R2 represent C1-C6 alkyl, C5-C7 cycloalkyl or C6-C12 aryl groups. In formula (I), R1, R2, m and n are defined as above and R represents nitrile, carboxylic acid amide and carboxylic acid groups. The inventive method is characterized in that a) compound (I) is reacted with water in the liquid phase in the presence of an organic, liquid dilution agent (III) to form a mixture (IV) containing a lactam (II) and said mixture (IV) is subjected to an aqueous treatment to obtain a two-phase system.
摘要:
A process is provided for the preparation of cyclic lactams of formula (II): in which n and m can each have the values 0, 1, 2, 3, 4, 5, 6, 7, 8 and 9 and the sum of n+m is at least 3, preferably at least 4, and R1 and R2 are C1-C6-alkyl, C5-C7-cycloalkyl or C6-C12-aryl groups, by reacting a compound (I) of the formula in which R1, R2, m and n are as defined above and R are [sic] nitrile, carboxamide and carboxylic acid groups, with steam in the gas phase.
摘要:
A process is provided for the preparation of caprolactam from a compound of formula (I): NC—(CH2)5—CO—R (I) in which R is a carboxamide, carboxylic acid or carboxylic acid ester group, wherein a) a compound (I) or a mixture of such compounds, in the presence of ammonia and optionally a liquid diluent (VI), is hydrogenated with hydrogen in the presence of a catalyst (II) to give a mixture (III), b) the hydrogen and the catalyst (II) are separated from the mixture (III) to give a mixture (IV), and c) the mixture (IV), optionally in the presence of a liquid diluent (VII), is converted to caprolactam in the presence of a catalyst (V).