EP1280767A1 - Verfahren zur herstellung von caprolactam aus 6-aminocapronitril und nachträgliche reinigung durch kristallisation - Google Patents

Verfahren zur herstellung von caprolactam aus 6-aminocapronitril und nachträgliche reinigung durch kristallisation

Info

Publication number
EP1280767A1
EP1280767A1 EP01927930A EP01927930A EP1280767A1 EP 1280767 A1 EP1280767 A1 EP 1280767A1 EP 01927930 A EP01927930 A EP 01927930A EP 01927930 A EP01927930 A EP 01927930A EP 1280767 A1 EP1280767 A1 EP 1280767A1
Authority
EP
European Patent Office
Prior art keywords
mixture
caprolactam
crystallization
water
boilers
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP01927930A
Other languages
German (de)
English (en)
French (fr)
Inventor
Peter Bassler
Dieter Baumann
Rolf-Hartmuth Fischer
Eberhard Fuchs
Johann-Peter Melder
Frank Ohlbach
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BASF SE
Original Assignee
BASF SE
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by BASF SE filed Critical BASF SE
Publication of EP1280767A1 publication Critical patent/EP1280767A1/de
Withdrawn legal-status Critical Current

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Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D201/00—Preparation, separation, purification or stabilisation of unsubstituted lactams
    • C07D201/02—Preparation of lactams
    • C07D201/08—Preparation of lactams from carboxylic acids or derivatives thereof, e.g. hydroxy carboxylic acids, lactones or nitriles

Definitions

  • the present invention relates to a process for the production of caprolactam, characterized in that
  • mixture (III) water is removed from mixture (III) to obtain a mixture (IV) containing caprolactam, high boilers and low boilers, and then
  • Caprolactarn which is used for the production of polymers, must have a purity of 99.9 to 99.94%, the major impurity is usually water in an amount of 0.04 to 0.1%. Other impurities may only be contained in the range of a maximum of a few ppm.
  • Caprolactam can be produced by Beckmann rearrangement of cyclohexanonoxim with sulfuric acid or oleum. After neutralizing the mixture obtained in this way with ammonia, the caprolactam can be obtained from the ammonium sulfate formed as a by-product by extraction with an organic solvent.
  • the crude caprolactam obtained by Beckmann rearrangement contains impurities, which can be found in Art and scope differ. Typical contaminants from crude caprolactam produced by the Beckmann rearrangement are C-methylcaprolactams, 6-methylvalerolactaiu and n-pentylacetamide.
  • the crude caprolac can be purified by hydrogenation in suspension in the presence of a catalyst and with the addition of an acid.
  • the crude caprolactam can be purified by hydrogenation in suspension in the presence of a catalyst and with the addition of a base.
  • DD-A-75083 describes a process for the purification of crude caprolactam in which the crude caprolactam is first distilled and then, dissolved in an organic solvent, hydrogenated in the presence of a catalyst and then treated with an ion exchanger.
  • the characteristic important quality characteristics for caprolactam can be maintained by continuously hydrogenating the crude caprolactam in a liquid phase process.
  • Crude caprolactam which by hydroformylation of 3-pentenoic acid and / or its esters to 5-formylvaleric acid (esters) as main products and 4- and 3-formylvaleric acid (esters) as by-products, extractive (WO 97/02228) or distillative ( WO 97/06126) separation of this branched formylvaleric acid (ester), aminating hydrogenation of 5-formylvaleric acid (esters) to 6-aminocaproic acid (esters) and / or ⁇ -aminocaproic acid amide and cyclization of 6-aminocaproic acid (esters) or 6-aminocaproic acid amide contains other typical impurities.
  • example 9 crude caprolactam obtained from mixtures of 6-aminocaproic acid, 6-aminocaproic acid amide and corresponding oligomers with addition of 10 wt .-% water to crystallize.
  • Crude caprolactam from which the high and low boilers were not separated prior to crystallization, contained 6345 ppm N-methylcaprolactam, 100 ppm 5-methylvalerolactam, 78 ppm valeramide and other impurities.
  • the crude caprolactam / water melt was homogenized at 50 ° C. and then cooled to 30 ° C.
  • caprolactam from mixtures with 4-ethyl-2-pyrrolidone, 5-methyl-2-piperidone, 3-ethyl-2-pyridolidone and 3-methyl-2-piperidone or octahydrophenazine on adsorbents such as activated carbon, molecular sieves or zeolites to be selectively adsorbed and to obtain highly pure caprolactam after desorption.
  • adsorbents such as activated carbon, molecular sieves or zeolites to be selectively adsorbed and to obtain highly pure caprolactam after desorption.
  • This Caprolac am separation can be followed by melt crystallization or crystallization from a solvent.
  • Caprolactam can also be obtained by reacting ACN with water in the liquid phase in the presence or absence of a catalyst with the release of ammonia.
  • the mixture obtained in this reaction contains, in addition to caprolactam, water, ammonia and any other liquid diluent, impurities with a boiling point above that of caprolactam ("high boilers”) and those with a boiling point below that of caprolactam (“low boilers”).
  • ACN is used in a first step in the
  • Typical impurities in a crude caprolactam obtained from ACN in the gas phase are, for example, cyanoalkyl- and aminoalkyl-substituted caprolactam derivatives and tetrahydroazepine derivatives such as N-cyanopentylhexamethyleneimine, N-cyanopentylcaprolactam, N- Aminohexylcaprolactam.
  • These impurities contribute to the deterioration of pure caprolactam in general for caprolactam, for example from Ulimann's Encyclopedia of Industrial Chemistry, 5th Ed., Vol.
  • the object of the present invention was to provide a process which enables the production of caprolactam, which was obtained in the gas phase from ACN, in high purity in a technically simple and energy-saving manner.
  • a mixture (I) containing 6-aminocapronitrile, water and optionally liquid diluent becomes a mixture (II) containing caprolactam, ammonia, water, optionally liquid diluent, high boilers and low boilers in the presence of a solid which catalytically promotes the reaction implemented in the gas phase.
  • the ACN required for step a) can be obtained from adiponitrile, as is known from Ullmann's Encyclopedia of Industrial Chemistry, 5th Ed., Vol. A5, VCH Verlagsgesellschaft mbH, Weinheim (Germany), 1986, page 46, Fig. 8 become.
  • 2,762,835, WO is particularly suitable 92/21650), nickel on aluminum oxide (US-A-2, 208, 598) or as a fixed bed catalyst Cu-Co-Zn spinel (DE-B-954416, US-A-2,257,814) or iron (DE-A-42 35,466) or a process according to US-A-2, 245, 129, US-A-2, 301, 964, EP-A-150295, FR-A-2 029 540 or one in US-A-5, 496 , 941 described method.
  • the adiponitrile required for this reaction is produced industrially, for example by double hydrocyanation of butadiene in the presence of nickel-containing catalysts, and is commercially available, for example, from Aldrich-Chemie Deutschen mbH & Co. KG, Steinheim, Germany.
  • the conversion of mixture (I) to mixture (II) can take place, for example, according to EP-A-659 741, WO 96/22974, DE 19632006, WO 99/47500 or WO 99/28296.
  • the reaction can preferably be carried out in the gas phase at temperatures of generally 200 to 550 ° C., preferably 250 to 400 ° C.
  • the pressure is generally in the range from 0.01 to 10 bar, preferably at atmospheric pressure, care being taken that the reaction mixture is predominantly gaseous under the conditions used.
  • the catalyst loads are usually 0.05 to 2, preferably 0.1 to 1.5, in particular 0.2 to 1 kg of 6-aminocapronitrile per liter of catalyst volume per hour.
  • the reaction can be carried out batchwise, preferably continuously.
  • Suitable reactors are advantageously those which are generally known for gas-phase reactions on moving or stationary solid catalysts.
  • Fluidized bed reactor preferably fixed bed reactor, such as a tray reactor, in particular a tubular reactor, can be used. Combinations of such reactors are also possible.
  • 1 to 50, preferably 1 to 10, mol of water are generally used per mol of ACN.
  • the mixture (I) can also contain further organic compounds which are in gaseous form under the reaction conditions, such as alcohols, amines or aromatic or aliphatic hydrocarbons.
  • Suitable catalytically active compounds of the catalysts are silicon dioxide as pyrogenically prepared silicon dioxide, as silica gel, diatomaceous earth, quartz or mixtures thereof, copper chromite, preferably aluminum oxide, titanium oxide, preferably titanium dioxide, lanthanum phosphates, lanthanum oxides, and also mixtures of such compounds.
  • Aluminum oxide is suitable in all modifications which can be obtained by heating the precursor compounds aluminum hydroxide (gibbsite, boehmite, pseudo-boehmite, bayerite and diaspor) at different temperatures. These include in particular gamma and alpha alumina and their mixtures.
  • Titanium dioxide is amorphous and suitable in all of its modifications, preferably anatase and rutile, and mixtures of such modifications.
  • Lanthanum phosphates in their various modifications, stoichiometric ratios between lanthanum and phosphate unit and degrees of condensation of the phosphate units are suitable individually or as a mixture.
  • These compounds can be used in the form of powders, grits, grit, strands or pressed into tablets.
  • the form of the compounds generally depends on the requirements of the particular reaction procedure, powder or semolina advantageously being used in a fluidized bed mode. In the fixed bed mode of operation, tablets or strands with diameters between 1 mm and 6 mm are usually used.
  • the compounds can be in pure form (content of the particular compound> 80% by weight), as a mixture of the above-mentioned compounds, the sum of the above-mentioned compounds should be> 80% by weight, or as a supported catalyst, the above-mentioned Connections can usually be applied to a mechanically and chemically stable support with a high surface area.
  • the pure compounds can be prepared by precipitation from aqueous solutions, e.g. Titanium dioxide after the sulfate process or by other methods such as the pyrogenic production of fine aluminum oxide, titanium dioxide or zirconium dioxide powders, which are commercially available.
  • aqueous solutions e.g. Titanium dioxide after the sulfate process
  • other methods such as the pyrogenic production of fine aluminum oxide, titanium dioxide or zirconium dioxide powders, which are commercially available.
  • the compounds or their precursor compounds which can be converted into the oxides by calcining can e.g. be prepared from solution by co-precipitation. A very good distribution of the two compounds used is generally obtained.
  • the compound or precursor mixtures can also be precipitated by precipitating one compound or precursor in the presence of the second compound or precursor present as a suspension of finely divided particles.
  • Another method consists in mechanically mixing the compound or precursor powders, which mixture can be used as a starting material for the production of strands or tablets.
  • the compounds can be applied to the support in the form of their brine simply by soaking them.
  • the volatile constituents of the sol are usually removed from the catalyst by drying and calcining.
  • Such brines are commercially available for titanium dioxide and aluminum oxide.
  • ke- Ramic support can be coated with titanium dioxide by hydrolysis of titanium isopropylate or other Ti alkoxides in a thin layer.
  • suitable compounds include TiCl4 and aluminum nitrate.
  • Suitable carriers are powders, strands or tablets of the compounds mentioned themselves or other stable compounds such as steatite or silicon carbide. The carriers used can be designed to be macroporous in order to improve the mass transport.
  • the reaction can be carried out in the presence of a gas which is inert with respect to the conversion of mixture (I) to mixture (II), preferably argon, in particular nitrogen.
  • a gas which is inert with respect to the conversion of mixture (I) to mixture (II) preferably argon, in particular nitrogen.
  • the volume ratio of the inert gas to the gaseous ACN under the reaction conditions can advantageously be up to 100.
  • step b) ammonia is removed from mixture (II) to give a mixture (III) containing caprolactam, water, optionally liquid diluent, high boilers and low boilers.
  • the ammonia can in principle be separated from mixture (II) by processes known per se for substance separation, such as extraction or preferably distillation, or a combination of such processes.
  • the distillation can advantageously be carried out at bottom temperatures of 60 to 220 ° C., in particular 100 to 220 ° C.
  • a pressure, measured at the top of the distillation apparatus, of 2 to 30 bar absolute is usually set.
  • the distillation can be carried out in several, such as 2 or 3 columns, advantageously in a single column.
  • step c) water and optionally liquid diluents are removed from mixture (III) to give a mixture (IV) containing caprolactam, high boilers and low boilers. If a liquid diluent was used in step a), water and liquid diluent can be separated off in step c) or the water before or after the liquid diluent.
  • the water can be separated from mixture (III) by processes known per se for the separation of substances, such as extraction, crystallization or preferably distillation, or a combination of such processes.
  • the distillation can advantageously be carried out at bottom temperatures of 50 to 250 ° C., in particular 100 to 230 ° C.
  • the distillation can be carried out in several, such as 2 or 3 columns, advantageously in a single column.
  • a heat-coupled, multi-stage separation of the water and, if appropriate, the liquid diluent is particularly preferred.
  • the low boilers and high boilers are separated off, advantageously only the high boilers are separated off, in particular neither the removal of high boilers and high boilers, particularly advantageously only the low boilers are removed from the mixture (IV). into consideration.
  • the low boilers can be separated off before, after or together with the high boilers.
  • the removal can in principle be carried out by processes known per se for the separation of materials, such as extraction, crystallization or preferably distillation, or a combination of such processes.
  • the distillation can advantageously be carried out at bottom temperatures of 50 to 250 ° C., in particular 100 to 230 ° C.
  • the distillation to remove the low boilers can be carried out in several, such as 2 or 3 columns, advantageously in a single column.
  • the distillation to remove the high boilers can advantageously be carried out in a number of columns, such as 2 or 3, in a single column.
  • a solid (V) containing caprolactam is obtained from mixture (IV) by partial crystallization, the proportion by weight of caprolactam in solid (V) being greater than in mixture (IV).
  • the sum of the contents of high boilers and low boilers, water and organic diluents not being included, in the mixture (IV) used in step d) is advantageously at least 100 ppm by weight, preferably 200 ppm by weight, particularly preferably at least 500% by weight . ppm, in particular at least 1000 ppm by weight based on mixture (IV).
  • the crystallization can be carried out batchwise.
  • the crystallization can be carried out continuously.
  • the crystallization can be carried out with the addition of an auxiliary, such as an organic or inorganic liquid diluent, for example water, preferably without the addition of an auxiliary.
  • an auxiliary such as an organic or inorganic liquid diluent, for example water
  • the crystallization can be carried out in one or more stages, such as two, three or four stages, preferably in one stage. In another preferred embodiment of the formation, the crystallization can be carried out as a fractional crystallization.
  • the temperature of the solution or melt during the crystallization is advantageously not above the melting point of caprolactam (70 ° C.), preferably between -i ⁇ and the melting point of caprolactam, in particular between 20 and the melting point of caprolactam.
  • the solids content in the crystallizer is usually between 0 and 70 g, preferably between 30 and 60 g per 100 g of use.
  • the crystallization takes place in apparatuses in which the crystals grow on cooled surfaces in the crystallization apparatus, i.e. are fixed in the apparatus (e.g. layer crystallization process from Sulzer Chemtech (Switzerland) or static crystallization process from BEFS PROKEM (France).
  • layer crystallization process from Sulzer Chemtech (Switzerland) or static crystallization process from BEFS PROKEM (France).
  • the crystallization can be carried out by cooling apparatus walls or by evaporating a solution of the crude caprolactam in vacuo. 5 to 30% by weight solutions of the crude caprolactam in a liquid diluent, in particular water, are particularly suitable for this.
  • the heat can be dissipated via scratch coolers which are connected to a stirred tank or a container without an agitator.
  • the circulation of the crystal suspension can be ensured by a pump.
  • Another preferred embodiment in cooling crystallization is the use of cooling disk crystallizers, such as those manufactured by Gouda (Holland).
  • the heat can be dissipated via conventional heat exchangers (preferably tube bundles or plate heat exchangers).
  • stirred kettles with wall-mounted stirrers or cooling crystal disks these devices have no device for avoiding crystal layers on the heat-transferring surfaces. If a state is reached in operation in which the thermal resistance takes on too high a value due to crystal layer formation, the switchover to a second one usually takes place Apparatus. During the operating time of the second apparatus, the first apparatus can be regenerated (preferably by melting the crystal layer or flushing the apparatus with unsaturated solution). If the heat transfer resistance in the second set is too high, switch back to the first set, etc. This variant can also be operated in alternation with more than two sets. In addition, the crystallization can be carried out by conventional evaporation of the solution in vacuo. '-
  • the crystals can be separated from the mother liquor by filtering and / or centrifuging.
  • the filtering or centrifuging can be preceded by a pre-thickening of the suspension, for example by one or more hydrocyclones.
  • Centrifuges which are known per se and which operate batchwise or continuously are suitable for centrifugation. Shear centrifuges that can be operated in one or more stages can be used most advantageously.
  • screw screen centrifuges or screw discharge centrifuges (decanters) are also suitable. Filtration can advantageously take place by means of filter grooves, which are operated discontinuously or continuously, with or without an agitator, or by means of a belt filter.
  • the filtering can be carried out under pressure or in vacuo.
  • the amount of washing liquid should preferably be between 0 and 500 g of washing liquid / 100 g of crystals, preferably between 30 and 200 g of washing liquid / 100 g of crystals.
  • washing liquids organic or inorganic liquids or mixtures of such liquids can be considered as washing liquid.
  • Preferred washing liquids are, for example
  • step d) a melt of a starting material used in a crystallization stage according to step d).
  • Washing can be carried out in the usual apparatus for this. Washing columns in which the mother liquor is separated and washed in one apparatus, centrifuges which can be operated in one or more stages, or filter chutes or belt filters can advantageously be used. Washing can be carried out on centrifuges or belt filters in one or more stages. Here, the washing liquid can be passed in countercurrent to the crystal cake.
  • the washing liquid can be returned to the crystallization, in particular in the case of crystallization without the addition of an auxiliary, optionally after removal of impurities.
  • Sweating is usually understood to mean local melting of contaminated areas.
  • the amount of perspiration is 0.1 to 90 g of melted crystals / 100 g of crystals before sweating, preferably 5 to 35 g of melted crystals / 100 g of crystals. Carrying out the joke on centrifuges or belt filters is particularly preferred. Carrying out a combination of washing and sweating in one apparatus can also be suitable.
  • the mother liquor can be returned to the crystallization, in particular in the case of crystallization without the addition of an auxiliary, optionally after removal of impurities.
  • caprolactam can be obtained in a purity of at least 99.90% by weight, preferably 99.90 to 99.99% by weight.
  • the caprolactam obtainable by the process according to the invention can be used for the production of polyamides, such as polycaprolactam.

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  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Other In-Based Heterocyclic Compounds (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
EP01927930A 2000-05-03 2001-04-30 Verfahren zur herstellung von caprolactam aus 6-aminocapronitril und nachträgliche reinigung durch kristallisation Withdrawn EP1280767A1 (de)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE10021192A DE10021192A1 (de) 2000-05-03 2000-05-03 Verfahren zur Herstellung von Caprolactam
DE10021192 2000-05-03
PCT/EP2001/004837 WO2001083443A1 (de) 2000-05-03 2001-04-30 Verfahren zur herstellung von caprolactam aus 6-aminocapronitril und nachträgliche reinigung durch kristallisation

Publications (1)

Publication Number Publication Date
EP1280767A1 true EP1280767A1 (de) 2003-02-05

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EP01927930A Withdrawn EP1280767A1 (de) 2000-05-03 2001-04-30 Verfahren zur herstellung von caprolactam aus 6-aminocapronitril und nachträgliche reinigung durch kristallisation

Country Status (13)

Country Link
US (1) US6683179B2 (zh)
EP (1) EP1280767A1 (zh)
JP (1) JP2003531893A (zh)
KR (1) KR20030013398A (zh)
CN (1) CN1174965C (zh)
AU (1) AU5482001A (zh)
BR (1) BR0110483A (zh)
CA (1) CA2407728A1 (zh)
DE (1) DE10021192A1 (zh)
MX (1) MXPA02009714A (zh)
MY (1) MY122991A (zh)
TW (1) TWI239329B (zh)
WO (1) WO2001083443A1 (zh)

Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP1405846A1 (en) * 2002-10-01 2004-04-07 DSM IP Assets B.V. Process for the preparation of epsilon-caprolactam from a mixture comprising 6-aminocaproamide and/or oligomers
DE10253094A1 (de) 2002-11-13 2004-05-27 Basf Ag Verfahren zur Reinigung von Caprolactam
DE10253095A1 (de) * 2002-11-13 2004-06-17 Basf Ag Verfahren zur Reinigung von Caprolactam
TWI520944B (zh) * 2015-02-13 2016-02-11 中國石油化學工業開發股份有限公司 己內醯胺之製造方法及其系統
WO2018074598A1 (ja) * 2016-10-21 2018-04-26 国立大学法人 岡山大学 赤色顔料用酸化鉄及びその製造方法

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SU75083A1 (ru) 1948-05-19 1948-11-30 Л.В. Зильперт Способ повышени светостойкости пластических масс или лакокрасочных покрытий на основе полихлорвинила, содержащих в качестве пластификатора диметилфталат
DE1253716B (de) 1961-09-28 1967-11-09 Basf Ag Verfahren zur Reinigung von Lactamen
DE3925575A1 (de) 1989-08-02 1991-02-07 Basf Ag Verfahren zur kontinuierlichen reinigung von caprolactam
FR2714379B1 (fr) 1993-12-23 1996-02-02 Rhone Poulenc Chimie Procédé de préparation de lactame.
DE19500041A1 (de) 1995-01-03 1996-07-04 Basf Ag Verfahren zur kontinuierlichen Reinigung von aus 6-Aminocapronitril hergestelltem Roh-Caprolactam
FR2729949A1 (fr) 1995-01-27 1996-08-02 Rhone Poulenc Chimie Procede de preparation de lactame
AU6244496A (en) 1995-07-04 1997-02-05 Dsm N.V. Process to prepare 5-formylvaleric acid
DE19529239A1 (de) 1995-08-09 1997-02-13 Basf Ag Verfahren zur kontinuierlichen Reindarstellung von 5-Formylvaleriansäureestern
EP0860431A1 (en) 1997-02-19 1998-08-26 Dsm N.V. Process to prepare e-caprolactam
DE19753301A1 (de) * 1997-12-01 1999-06-02 Basf Ag Verfahren zur Herstellung von Lactamen
DE19811880A1 (de) 1998-03-18 1999-09-23 Basf Ag Verfahren zur Herstellung von Lactamen
EP0943608A1 (en) 1998-03-20 1999-09-22 Dsm N.V. Process for the continuous purification of crude epsilon--caprolactam
CA2335114A1 (en) * 1998-06-15 1999-12-23 George Ernest Ii Keller Separation of epsilon caprolactam from isomers

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Publication number Publication date
WO2001083443A1 (de) 2001-11-08
KR20030013398A (ko) 2003-02-14
MXPA02009714A (es) 2003-04-22
CN1174965C (zh) 2004-11-10
CN1427820A (zh) 2003-07-02
CA2407728A1 (en) 2002-10-29
BR0110483A (pt) 2003-04-08
DE10021192A1 (de) 2001-11-08
AU5482001A (en) 2001-11-12
US20030105322A1 (en) 2003-06-05
JP2003531893A (ja) 2003-10-28
US6683179B2 (en) 2004-01-27
TWI239329B (en) 2005-09-11
MY122991A (en) 2006-05-31

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