Abstract:
A process is disclosed for preparing carboxylic acid derivatives having the general formula (I), in which X stands for OR2 or NH¿2, R?1 stands for C¿1?-C20 alkyl, C1-C20 hydroxyalkyl, C3-C12-cycloalkyl, C4-C12 alkyl-cycloalkyl, C4-C12-cycloalkyl-alkyl, C5-C20 alkyl-cycloalkyl-alkyl, aryl, C7-C20 aralkyl, C7-C20 alkylaryl, an heteroaliphatic or heteroaromatic ring with 5 to 8 carbon atoms and R?2¿ stands for C¿1?-C20 alkyl, from carboxylic acid nitriles having the general formula (II) R?1¿-C N, in which R1 has the above-mentioned meanings, and from alcohols having the general formula (III) R2-OH, in which R2 has the above-mentioned meanings. The reaction is carried out in the liquid phase at temperatures from 50 to 300 °C and pressures from 0.1 to 350 bars in the presence of an heterogeneous catalyst.
Abstract:
The invention relates to a method for producing amines of general formula (I) X(-CH2-NHR)n in which R independently represents C1-200-alkyl, C3-8-cycloalkyl, C4-20-alkyl cycloalkyl, C4-20-cylcoalkyl alkyl, C2-20-alkoxyalkyl, aryl, C7-20-alkylaryl, C7-20-aryl alkyl, C2-8-hyrodoxyalkyl, C2-8-mercaptoalkyl, C8-20-aryloxyalkyl or jointly represents a saturated or unsaturated C2-6-alkylene chain which is optionally substituted singly to triply by C1-4-alkyl and is optionally interrupted by oxygen or nitrogen. X is a C1-20-alkyl, C2-20-alkenyl or C3-8-cycloalkyl with n free valances optionally substituted by C1-20-alkyl, C3-8-cycloalkyl, C4-20-alkyl cycloalkyl, C4-20-cycloalkyl alkyl, C2-20-alkoxyalkyl, aryl, C7-20-alkylaryl, C7-20-aryl alkyl, C1-20-alkoxy, hydroxy, C1-20-hyrodoxyalkyl, amino, C1-20-alkyl amino, C2-20-dialkyl amino, C2-12-alkenyl amino, C3-8-cycloalkyl amino, aryl amino, diaryl amino, aryl-C1-8-alkyl amino, halogen, mercapto, C2-20-alkenyloxy, C3-8-cycloalkoxy, aryloxy, and C2-8-alkoxycarbonyl, and n is a whole number from 1 to 4. The amines are produced by reacting nitriles of general formula (II) X(-CN)n in which X and n have the above mentioned meanings with primary amines of general formula (III) H2NR in which R has the above mentioned meanings, and with hydrogen at temperatures ranging from 50 to 250 DEG C and pressure ranging from 5 to 350 bar in the presence of a catalyst containing Pd, whereby the catalyst comprises 0.1 to 10 wt. % Pd on a carrier, said wt. % being relative to the total weight of the catalyst.
Abstract:
THE DISCLOSURE IS A PROCESS FOR PREPARING CYCLIC LACTAMS OF THE FORMULA 1:WHERE R1 IS HYDROGEN, ALKYL, CYCLOALKYL OR ARYL, AND A IS C3-C12-ALKYLENE UNSUBSTITUTED OR SUBSTITUTED BY 1,2, 3, 4, 5 OR 6 SUBSTITUTUENTS SELECTED INDEPENDENTLY OF ONE ANOTHER FROM THE GROUP CONSISTING OF ALKYL, CYCLOALKYL AND ARYL, BY CONVERSION OF AN W-AMINOCARBONITRILE OF THE FORMULA 2;ER1N -A – CN WHERE R1 AND A ARE EACH AS DEFINED ABOVE, IN THE PRESENCE OF AT LEAST ONE CATALYST, WHICH COMPRISES CONVERTING SAID NITRILE II INTO AN OLIGOMER MIXTURE, AND TREATING WITH SUPERHEATED STEAM.
Abstract:
The invention relates to a continuous method for producing a polyamide, comprising the following steps: (1) reaction of at least one aminonitrile with water at a temperature of between 90 and 400 .degree.C and a pressure of between 0.1 and 35 .times. 10 6 Pa in a tubular flow reactor containing a Bronsted acid catalyst selected from a beta zeolite, sheet silicate or titanium dioxide catalyst (2) further reaction of the reaction mixture at a temperature of between 150 and 400 .degree.C and a pressure which is lower than the pressure in step 1, where the temperature and pressure are selected such that a first gaseous phase and a first liquid or first solid phase or a mixture of a first solid and first liquid phase is obtained, and the first gaseous phase is separated; an d (3) addition of the first liquid and/or first solid phase to a gaseous or liquid phase containing water, at a temperature of between 150 and 370 .degree.C and a pressure of between 0.1 and 30 x 10 6 Pa, resulting in a product mixture.
Abstract:
Cyclic lactams are prepared by reacting an aminocarboxylic acid compound of the formula I H2N-(CH2)m-COR1 I where R1 is -OH, -O-C1-C12-alkyl or -NR2R3 and R2 and R3, independently of one another, are each hydrogen, C1-C12-alkyl or C5-C8-cycloalkyl and m is an integer from 3 to 12, with water by a process in which the reaction is carried out in the liquid phase using a heterogeneous catalyst.
Abstract:
Method for preparing caprolactam by heating 6-aminocapric acid nitrile in the presence of heterogeneous catalysts and water under elevated pressure, wherein (a) 6-aminocapric acid nitrile or a mixture containing essentially 6-aminocapric acid nitrile as well as water and a low-boiling or a high-boiling alcohol is heated in the presence of a heterogeneous catalyst in a reactor A to produce a mixture (I); then (b) mixture (I) is distilled, yielding a head fraction, caprolactam and a bottom product, with any ammonia in mixture (I) being removed prior to distillation; and then (c1) the head fraction is fed into the reactor of step (a), with the head fraction optionally being mixed with the alcohol and/or water and/or 6-aminocapric nitrile used in step (a) before being fed into reactor (A); or (c2) the head fraction, optionally with the bottom product from step (b), is fed into a reactor (B), the first fraction optionally being mixed with the alcohol and/or water and/or 6-aminocapric acid nitrile before being fed into reactor (B), and then analogously to step (b) caprolactam is produced by distillation; and either (d1) the bottom product from step (b) is fed into reactor A of step (a); or (d2) optionally water and possibly a low-boiling or a high-boiling alcohol are added to the bottom product which then, analogously to step (a) is heated in a reactor (C) to give a reaction product which is distilled to yield caprolactam; or (d3) water is added to the bottom product which is heated in a reactor (D) without added catalyst to give a reaction product which is distilled to yield caprolactam; or (d4) water and a base are added to the bottom product which is heated in reactor (E) to give a reaction product which is distilled to yield caprolactam.
Abstract:
The invention concerns the simultaneous preparation of caprolactam and hexamethylene diamine from adipodinitrile, by the following steps: (a) the adipodinitrile is partially hydrogenated, producing a mixture substantially containing 6-aminocapronitrile, hexamethylene diamine, ammonia, adipodinitrile and hexamethylene imine (= "the mixture"); (b) the mixture obtained in step (a) is distilled, producing ammonia, as the forerunnings, and a residue I, in the presence of a compound A which is inert in the distillation conditions, the ammonia not being separated totally; (c) the residue I, substantially containing "the mixture", inert compound A and ammonia, the ammonia content being less than that of the mixture used in step (b), is subjected to a second distillation, producing a mixture of the inert compound A and ammonia, as the forerunnings, and a residue II; (d) the base II, substantially containing "the mixture" and inert compound A, is subjected to distillation in a third column, producing the inert compound A, as the forerunnings, and a residue III; (e) the base III, substantially containing "the mixture" and optionally an inert compound B, is subjected to distillation in a fourth column, producing forerunnings KP1, which substantially contain hexamethylene imine, optionally inert compound B and hexamethylene diamine, and a residue IV; (f) the forerunnings KP1 are subjected in a fifth column to distillation, producing forerunnings KP2, which substantially contain hexamethylene imine and optionally inert compound B, and a residue V, which substantially contains hexamethylene diamine with a degree of purity of at least 95 %, the forerunnings KP2 being fed to the third column or optionally only partially fed to the third column, and the rest being discarded; and (g) the residue IV, substantially containing 6-aminocapronitrile and adipodinitrile, is subjected in a sixth column to distillation, producing 6-aminocapronitrile with a degree of purity of at least 95 %, as forerunnings, and adiponitrile in the residue. The resultant 6-aminocapronitrile is cyclized to form caprolactam.
Abstract:
A process is proposed for manufacturing cyclic lactams by allowing aminocarbozyGc acid nitrites to react with water. This is done in the liquid phase in the presence of heterogeneous catalysts based ou ntanium dioxide, zirconium ozide, cerium oxide and aluminium oxide.
Abstract:
Crude capronitrile is purified by hydrogenation, subsequent treatment in an acidic medium and subsequent distillation in an alkaline medium, by a process in which (a) 6-aminocapronitrile is converted into crude caprolactam by reaction with water, (b) high boilers and low boilers are separated off from the crude caprolactam from step (a), (c) the crude caprolactam from step (b) is treated with hydrogen at from 50 DEG to 150 DEG C. and from 1.5 to 250 bar in the presence of a hydrogenation catalyst and, if desired, of a solvent to give a mixture A, (d1) mixture A in a solvent is passed, at from 30 DEG to 80 DEG C. and from 1 to 5 bar, over an ion exchanger containing terminal acid groups to give a mixture B1, or (d2) mixture A is distilled in the presence of sulfuric acid, any solvent present being removed before the addition of the sulfuric acid, to give a mixture B2, and (e) mixture B1 or mixture B2 is distilled in the presence of a base to give pure caprolactam.