WO2009150075A1 - Method for producing n-vinylpyrrolidone in a stainless steel reactor - Google Patents

Method for producing n-vinylpyrrolidone in a stainless steel reactor Download PDF

Info

Publication number
WO2009150075A1
WO2009150075A1 PCT/EP2009/056710 EP2009056710W WO2009150075A1 WO 2009150075 A1 WO2009150075 A1 WO 2009150075A1 EP 2009056710 W EP2009056710 W EP 2009056710W WO 2009150075 A1 WO2009150075 A1 WO 2009150075A1
Authority
WO
WIPO (PCT)
Prior art keywords
stainless steel
lactam
lactams
vinylpyrrolidone
vinyl
Prior art date
Application number
PCT/EP2009/056710
Other languages
German (de)
French (fr)
Inventor
Regina Vogelsang
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 WO2009150075A1 publication Critical patent/WO2009150075A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07D—HETEROCYCLIC COMPOUNDS
    • C07D207/00—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom
    • C07D207/02—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom
    • C07D207/18—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member
    • C07D207/22—Heterocyclic compounds containing five-membered rings not condensed with other rings, with one nitrogen atom as the only ring hetero atom with only hydrogen or carbon atoms directly attached to the ring nitrogen atom having one double bond between ring members or between a ring member and a non-ring member with hetero atoms or with carbon atoms having three bonds to hetero atoms with at the most one bond to halogen, e.g. ester or nitrile radicals, directly attached to ring carbon atoms
    • C07D207/24—Oxygen or sulfur atoms
    • C07D207/26—2-Pyrrolidones
    • C07D207/263—2-Pyrrolidones with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to other ring carbon atoms
    • C07D207/267—2-Pyrrolidones with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to other ring carbon atoms with only hydrogen atoms or radicals containing only hydrogen and carbon atoms directly attached to the ring nitrogen atom

Definitions

  • the invention relates to a process for the preparation of N-vinyl lactams by reacting lactams with acetylene and subsequent workup of the resulting mixture, which is characterized in that devices which come into contact with N-vinyl lactams at a temperature greater than 30 0 C, made of stainless steel are.
  • N-vinyl lactams e.g. N-vinylpyrrolidone can be prepared in a known manner by reacting the corresponding lactams with acetylene. Such a method is e.g. described in DE-A 102 55 437.
  • the resulting vinyl compound can easily polymerize prematurely at higher temperatures.
  • the resulting polymer reduces the yield of vinyl compound and forces process interruptions to remove the formed polymer from time to time.
  • WO 2006/118319 describes the storage of N-vinyllactams in stainless steel containers.
  • the object of the present invention was therefore a process for the preparation of N-vinyl lactams in which formation of polymers does not occur or hardly occurs.
  • N-vinyl lactams which have a temperature greater than 30 0 C, in particular greater than 50 0 C and particularly preferably greater than 70 0 C, of stainless steel.
  • an alloyed steel having a carbon content of less than 2 wt.%, Particularly preferably less than 1, 5 wt.% And a content of alloying metals greater than 3 wt.%, Preferably greater than 5 wt.%.
  • the stainless steel may contain, apart from carbon, other non-metallic constituents, such as phosphorus or sulfur. However, the content of such other constituents is generally low and is less than 2% by weight, preferably less than 1% by weight, more preferably less than 0.5% by weight and most preferably less than 0.1% by weight.
  • the alloying elements are preferably selected from molybdenum, chromium, cobalt, manganese, nickel, vanadium, niobium, tantalum, titanium, zirconium, aluminum and lead.
  • the stainless steel may contain only one of the above alloying elements, but it may also contain any mixtures of the listed elements.
  • the stainless steel contains a total of more than 3 wt.%, In particular more than 5 wt.% Alloy elements selected from molybdenum, chromium, vanadium, nickel or any mixtures of these alloying elements.
  • the stainless steel contains both molybdenum and chromium; It contains in particular at least 1% by weight, more preferably at least 2% by weight of molybdenum, most preferably at least 3% by weight of molybdenum and at least 1% by weight of chromium, more preferably at least 2% by weight of chromium and most preferably at least 3% by weight .% Chrome.
  • an excessively high content of alloying metals is not necessary.
  • a total content of at most 30% by weight, in particular not more than 20% by weight, preferably not more than 15% by weight, of alloying metals is sufficient.
  • all devices which have in particular greater than 50 0 C and particularly preferably greater than 70 0 C and N-vinyl lactams which have a temperature greater than 30 0 C, come into contact with stainless steel.
  • devices is understood to mean plant components such as reactors, columns, vessels, separators, evaporators, condensers and pipelines.
  • the N-vinyl lactams naturally have in the reactor and in a subsequent distillation a corresponding temperature greater than 30 0 C, in particular greater than 50 0 C and particularly preferably greater than 70 0 C; Also in the other devices or parts of the system, the N-vinyl lactam is present at appropriate temperatures.
  • N-vinyllactams are N-vinylcaprolactam, N-vinylpiperidone and N-vinylpyrrolidone.
  • the lactam is preferably 2-pyrrolidone (gamma-butyrolactam) and the N-vinyllactam is N-vinylpyrrolidone.
  • lactams are reacted with acetylene.
  • the process according to the invention can be carried out batchwise, semicontinuously or continuously. It is particularly preferably carried out continuously, wherein the lactam and acetylene are fed continuously to the reaction zone and the resulting mixture is continuously removed from the reaction zone and then worked up if necessary.
  • the lactam is first reacted with an alkali hydroxide prior to reaction.
  • an alkali hydroxide can be z. B. be a lithium, sodium or potassium hydroxide; particularly preferred is potassium hydroxide.
  • the corresponding alkali salt of the lactam e.g. in the case of pyrrolidone pyrrolidate, or potassium pyrrolidate.
  • the amount of alkali metal hydroxide is preferably chosen such that 0.25 to 25 wt.%, Preferably 1 to 10 wt.% Of the lactam is present as alkali metal salt (pyrrolidone as pyrrolidate, or potassium pyrrolidate).
  • the alkali salt catalyzes the subsequent reaction with acetylene (vinylation).
  • the effluent from the above column may be mixed with further lactam (pyrrolidone).
  • the lactam (pyrrolidone) used for the reaction with acetylene can then in particular 0.25 to 10 wt.%, In particular 1, 5 to 6 wt.% Alkali salt (pyrrolidate) included.
  • the reaction of the lactam with acetylene takes place according to the invention in a reactor made of stainless steel.
  • the reactor may be any reactor, called z. B. stirred tank, stirred tank cascades, tubular reactors or loop reactors.
  • the reaction of the lactam with acetylene is preferably carried out at temperatures of 120 to 220, more preferably at 140 to 170 0 C and preferably at pressures of 1, 0 to 25 and particularly preferably from 10 to 20 bar.
  • the product mixture obtained is preferably worked up.
  • N-vinyl lactam is distilled off.
  • the distillation may be carried out in one or more stages, i. be carried out in one or more columns.
  • N-vinyl lactam is preferably distilled off overhead and unreacted lactam, which is obtained in the bottom of the column, are recycled and further purified in one or more subsequent distillation (pure distillation) N-vinyl lactam.
  • Suitable columns are packed columns or packed columns, which in particular are operated continuously. Also suitable are columns which contain both random packings and packings, for. B. contain in the lower part Med Engineering organization and in the upper part with packing elements (eg., Built steel sheets) have.
  • the columns may preferably have at least two, more preferably at least 3 theoretical plates.
  • the number of theoretical plates can, for. B. 2 to 100, in particular 3 to 20.
  • the N-vinyllactam can generally be obtained with a purity of more than 98% by weight, in particular more than 99% by weight, particularly preferably more than 99.5% by weight.
  • the polymer formation is significantly reduced in the process according to the invention.
  • commercial stabilizers may additionally be added which inhibit polymerization.
  • the polymer formation in the process according to the invention is so low that it is possible to dispense with the addition of such stabilizers.
  • Freshly distilled N-vinylpyrrolidone was stored at 60 ° C. under nitrogen.
  • the N-vinylpyrrolidone contained the steels in the form of chips given in the table.
  • the polymer content (based on the initial amount of N-vinylpyrrolidone was determined after 22 days.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Pyrrole Compounds (AREA)

Abstract

The invention relates to a method for producing N-vinyl lactams by reacting lactams with acetyls and then processing the resulting mixture, characterized in that devices that come into contact with the N-vinyl lactams at a temperature of more than 30°C are made of steel.

Description

Verfahren zur Herstellung von N-Vinylpyrrolidon in einem Edelstahlreaktor Process for the preparation of N-vinylpyrrolidone in a stainless steel reactor
Beschreibungdescription
Die Erfindung betrifft ein Verfahren zur Herstellung von N-Vinyllactamen durch Umsetzung von Lactamen mit Acetylen und anschließende Aufarbeitung des erhaltenen Gemischs, welches dadurch gekennzeichnet ist, dass Vorrichtungen, die mit N- Vinyllactamen bei einer Temperatur größer 30 0C in Kontakt kommen, aus Edelstahl sind.The invention relates to a process for the preparation of N-vinyl lactams by reacting lactams with acetylene and subsequent workup of the resulting mixture, which is characterized in that devices which come into contact with N-vinyl lactams at a temperature greater than 30 0 C, made of stainless steel are.
N-Vinyllactame, z.B. N-Vinylpyrrolidon, können bekannter Weise durch Umsetzung der entsprechenden Lactame mit Acetylen hergestellt werden. Ein derartiges Verfahren ist z.B. in der DE-A 102 55 437 beschrieben. Die erhaltene Vinylverbindung kann bei höheren Temperaturen leicht vorzeitig polymerisieren. Das gebildete Polymerisat vermin- dert die Ausbeute an Vinylverbindung und zwingt zu Verfahrensunterbrechungen, um das gebildete Polymerisat von Zeit zu Zeit zu entfernen.N-vinyl lactams, e.g. N-vinylpyrrolidone can be prepared in a known manner by reacting the corresponding lactams with acetylene. Such a method is e.g. described in DE-A 102 55 437. The resulting vinyl compound can easily polymerize prematurely at higher temperatures. The resulting polymer reduces the yield of vinyl compound and forces process interruptions to remove the formed polymer from time to time.
In WO 2006/118319 ist die Lagerung von N-Vinyllactamen in Edelstahlbehältern beschrieben.WO 2006/118319 describes the storage of N-vinyllactams in stainless steel containers.
Aus DE-A- 19839565 ist die Verwendung von rostfreien Stahlautoklaven für die Umsetzung von Acetylen mit Lactamen bekannt.From DE-A-19839565 the use of stainless steel autoclaves for the reaction of acetylene with lactams is known.
Aufgabe der vorliegenden Erfindung war daher ein Verfahren zur Herstellung von N- Vinyllactamen bei dem eine Bildung von Polymeren nicht oder kaum auftritt.The object of the present invention was therefore a process for the preparation of N-vinyl lactams in which formation of polymers does not occur or hardly occurs.
Demgemäß wurde das eingangs definierte Verfahren gefunden.Accordingly, the method defined above was found.
Bei dem erfindungsgemäßen Verfahren sind Vorrichtungen, die mit N-Vinyllactamen, welche eine Temperatur größer 30 0C, insbesondere größer 500C und besonders bevorzugt größer 70 0C haben, in Kontakt kommen, aus Edelstahl.In the inventive method are devices which come in contact with N-vinyl lactams which have a temperature greater than 30 0 C, in particular greater than 50 0 C and particularly preferably greater than 70 0 C, of stainless steel.
Unter Edelstahl wird hier vorzugsweise ein legierter Stahl mit einem Kohlenstoffgehalt kleiner 2 Gew. %, besonders bevorzugt kleiner 1 ,5 Gew. % und einem Gehalt an Le- gierungsmetallen größer 3 Gew. %, bevorzugt größer 5 Gew. % verstanden.Under stainless steel is here preferably understood an alloyed steel having a carbon content of less than 2 wt.%, Particularly preferably less than 1, 5 wt.% And a content of alloying metals greater than 3 wt.%, Preferably greater than 5 wt.%.
Der Edelstahl kann, abgesehen vom Kohlenstoff, noch sonstige nicht-metallische Bestandteile, wie Phosphor oder Schwefel enthalten. Der Gehalt derartiger sonstiger Bestandteile ist aber im Allgemeinen gering und liegt unter 2 Gew. %, vorzugsweise unter 1 Gew. %, besonders bevorzugt unter 0,5 Gew. % und ganz besonders bevorzugt unter 0,1 Gew. %. Die Legierungselemente sind vorzugsweise ausgewählt aus Molybdän, Chrom, Kobalt, Mangan, Nickel, Vanadium, Niob, Tantal, Titan, Zirkonium, Aluminium und Blei. Der Edelstahl kann nur eines der genannten Legierungselemente enthalten, er kann aber auch beliebige Mischungen der aufgeführten Elemente enthalten.The stainless steel may contain, apart from carbon, other non-metallic constituents, such as phosphorus or sulfur. However, the content of such other constituents is generally low and is less than 2% by weight, preferably less than 1% by weight, more preferably less than 0.5% by weight and most preferably less than 0.1% by weight. The alloying elements are preferably selected from molybdenum, chromium, cobalt, manganese, nickel, vanadium, niobium, tantalum, titanium, zirconium, aluminum and lead. The stainless steel may contain only one of the above alloying elements, but it may also contain any mixtures of the listed elements.
In einer besonderen Ausführungsform enthält der Edelstahl insgesamt mehr als 3 Gew. %, insbesondere mehr als 5 Gew. % Legierungselemente ausgewählt aus Molybdän, Chrom, Vanadium, Nickel oder beliebiger Mischungen dieser Legierungselemente.In a particular embodiment, the stainless steel contains a total of more than 3 wt.%, In particular more than 5 wt.% Alloy elements selected from molybdenum, chromium, vanadium, nickel or any mixtures of these alloying elements.
In einer besonders bevorzugten Ausführungsform enthält der Edelstahl sowohl Molybdän als auch Chrom; er enthält insbesondere mindestens 1 Gew. %, besonders bevorzugt mindestens 2 Gew. % Molybdän, ganz besonders bevorzugt mindestens 3 Gew. % Molybdän und mindestens 1 Gew. % Chrom, besonders bevorzugt mindestens 2 Gew. % Chrom und ganz besonders bevorzugt mindestens 3 Gew. % Chrom.In a particularly preferred embodiment, the stainless steel contains both molybdenum and chromium; It contains in particular at least 1% by weight, more preferably at least 2% by weight of molybdenum, most preferably at least 3% by weight of molybdenum and at least 1% by weight of chromium, more preferably at least 2% by weight of chromium and most preferably at least 3% by weight .% Chrome.
Für die Zwecke dieser Erfindung ist ein übermäßig hoher Gehalt an Legierungsmetallen nicht notwendig. Ein Gehalt von insgesamt maximal 30 Gew. %, insbesondere maximal 20 Gew. %, vorzugsweise maximal 15 Gew. % Legierungsmetalle ist ausreichend.For the purposes of this invention, an excessively high content of alloying metals is not necessary. A total content of at most 30% by weight, in particular not more than 20% by weight, preferably not more than 15% by weight, of alloying metals is sufficient.
Erfindungsgemäß sind alle Vorrichtungen, die mit N-Vinyllactamen, welche eine Temperatur größer 30 0C haben insbesondere größer 500C und besonders bevorzugt größer 70 0C haben, in Kontakt kommen, aus Edelstahl.According to the invention, all devices, which have in particular greater than 50 0 C and particularly preferably greater than 70 0 C and N-vinyl lactams which have a temperature greater than 30 0 C, come into contact with stainless steel.
Unter dem Begriff Vorrichtungen werden hier Anlagenteile wie Reaktoren, Kolonnen, Behälter, Abscheider, Verdampfer, Kondensatoren und Rohrleitungen verstanden.The term devices is understood to mean plant components such as reactors, columns, vessels, separators, evaporators, condensers and pipelines.
Die N-Vinyllactame haben naturgemäß im Reaktor und bei einer anschließenden Destillation eine entsprechende Temperatur größer 30 0C, insbesondere größer 500C und besonders bevorzugt größer 70 0C; auch in den anderen Vorrichtungen bzw. Anlagenteilen liegt das N-Vinyllactam bei entsprechenden Temperaturen vor.The N-vinyl lactams naturally have in the reactor and in a subsequent distillation a corresponding temperature greater than 30 0 C, in particular greater than 50 0 C and particularly preferably greater than 70 0 C; Also in the other devices or parts of the system, the N-vinyl lactam is present at appropriate temperatures.
Das erfindungsgemäße Verfahren eignet sich zur Herstellung von N-Vinyllactamen. Bevorzugte N-Vinyllactame sind N-Vinylcaprolactam, N-Vinylpiperidon und N- Vinylpyrrolidon.The process according to the invention is suitable for the preparation of N-vinyllactams. Preferred N-vinyllactams are N-vinylcaprolactam, N-vinylpiperidone and N-vinylpyrrolidone.
Bevorzugt handelt es sich bei dem Lactam um 2- Pyrrolidon (gamma-Butyrolactam) und bei dem N-Vinyllactam um N-Vinylpyrrolidon.The lactam is preferably 2-pyrrolidone (gamma-butyrolactam) and the N-vinyllactam is N-vinylpyrrolidone.
Beim erfindungsgemäßen Verfahren werden Lactame mit Acetylen umgesetzt. Das erfindungsgemäße Verfahren kann diskontinuierlich, halbkontinuierlich oder kontinuierlich durchgeführt werden. Besonders bevorzugt wird es kontinuierlich durchgeführt, wobei das Lactam und Acetylen der Reaktionszone kontinuierlich zugeführt und das erhaltene Gemisch kontinuierlich aus der Reaktionszone entfernt und danach ge- gebenenfalls aufgearbeitet wird.In the process according to the invention, lactams are reacted with acetylene. The process according to the invention can be carried out batchwise, semicontinuously or continuously. It is particularly preferably carried out continuously, wherein the lactam and acetylene are fed continuously to the reaction zone and the resulting mixture is continuously removed from the reaction zone and then worked up if necessary.
In einer Ausführungsform wird das Lactam vor der Umsetzung zunächst mit einem Alkalihydroxid umgesetzt. Es kann sich z. B. um ein Lithium-, Natrium- oder Kaliumhydroxid handeln; besonders bevorzugt ist Kaliumhydroxid. Bei der Umsetzung bildet sich das entsprechende Alkalisalz des Lactams, z.B. im Falle des Pyrrolidons das Pyr- rolidat, bzw. Kaliumpyrrolidat. Die Menge an Alkalihydroxid wird vorzugsweise so gewählt, dass 0,25 bis 25 Gew. %, vorzugsweise 1 bis 10 Gew. % des Lactams als Alkalisalz (Pyrrolidon als Pyrrolidat, bzw. Kaliumpyrrolidat) vorliegt. Das Alkalisalz katalysiert die anschließende Umsetzung mit Acetylen (Vinylierung). Der Austrag aus der vorstehenden Kolonne kann mit weiterem Lactam (Pyrrolidon) gemischt werden.In one embodiment, the lactam is first reacted with an alkali hydroxide prior to reaction. It can be z. B. be a lithium, sodium or potassium hydroxide; particularly preferred is potassium hydroxide. In the reaction, the corresponding alkali salt of the lactam, e.g. in the case of pyrrolidone pyrrolidate, or potassium pyrrolidate. The amount of alkali metal hydroxide is preferably chosen such that 0.25 to 25 wt.%, Preferably 1 to 10 wt.% Of the lactam is present as alkali metal salt (pyrrolidone as pyrrolidate, or potassium pyrrolidate). The alkali salt catalyzes the subsequent reaction with acetylene (vinylation). The effluent from the above column may be mixed with further lactam (pyrrolidone).
Das für die Umsetzung mit Acetylen verwendete Lactam (Pyrrolidon) kann dann insbesondere 0,25 bis 10 Gew. %, insbesondere 1 ,5 bis 6 Gew. % Alkalisalz (Pyrrolidat) enthalten.The lactam (pyrrolidone) used for the reaction with acetylene can then in particular 0.25 to 10 wt.%, In particular 1, 5 to 6 wt.% Alkali salt (pyrrolidate) included.
Die Umsetzung des Lactams mit Acetylen erfolgt erfindungsgemäß in einem Reaktor aus Edelstahl.The reaction of the lactam with acetylene takes place according to the invention in a reactor made of stainless steel.
Bei dem Reaktor kann es sich um einen beliebigen Reaktor handeln, genannt seien z. B. Rührkessel, Rührkesselkaskaden, Rohrreaktoren oder Schlaufenreaktoren.The reactor may be any reactor, called z. B. stirred tank, stirred tank cascades, tubular reactors or loop reactors.
Die Umsetzung des Lactams mit Acetylen erfolgt vorzugsweise bei Temperaturen von 120 bis 220, besonders bevorzugt bei 140 bis 170 0C und vorzugsweise bei Drucken von 1 ,0 bis 25 und besonders bevorzugt von 10 bis 20 bar.The reaction of the lactam with acetylene is preferably carried out at temperatures of 120 to 220, more preferably at 140 to 170 0 C and preferably at pressures of 1, 0 to 25 and particularly preferably from 10 to 20 bar.
Nach der Umsetzung wird das erhaltene Produktgemisch vorzugsweise aufgearbeitet.After the reaction, the product mixture obtained is preferably worked up.
Insbesondere erfolgt eine Aufarbeitung durch Destillation. Insbesondere wird das N- Vinyllactam abdestilliert. Die Destillation kann in einer oder mehreren Stufen, d.h. in einer oder mehrere Kolonnen durchgeführt werden. Bei einer mehrstufigen Destillation kann in einer ersten Destillation (Rohdestillation) N-Vinyllactam vorzugsweise über Kopf abdestilliert und nicht umgesetztes Lactam, welches im Kolonnensumpf anfällt, zurückgeführt werden und in einer oder mehreren anschließenden Destillationen (Reindestillation) N-Vinyllactam weiter gereinigt werden.In particular, a work-up by distillation. In particular, the N-vinyl lactam is distilled off. The distillation may be carried out in one or more stages, i. be carried out in one or more columns. In a multistage distillation, in a first distillation (crude distillation) N-vinyl lactam is preferably distilled off overhead and unreacted lactam, which is obtained in the bottom of the column, are recycled and further purified in one or more subsequent distillation (pure distillation) N-vinyl lactam.
Geeignete Kolonnen sind Füllkörperkolonnen oder Packungskolonnen, welche insbesondere kontinuierlich betrieben werden. Geeignet sind auch Kolonnen, die sowohl Füllkörper als auch Packungen enthalten, z. B. im unteren Teil Füllkörperschüttungen enthalten und im oberen Teil mit Packungselementen (z. B. eingebaute Stahlbleche) aufweisen.Suitable columns are packed columns or packed columns, which in particular are operated continuously. Also suitable are columns which contain both random packings and packings, for. B. contain in the lower part Füllkörperschüttungen and in the upper part with packing elements (eg., Built steel sheets) have.
Die Kolonnen können vorzugsweise mindestens zwei, besonders bevorzugt mindestens 3 theoretische Böden haben. Die Anzahl der theoretischen Böden kann z. B. 2 bis 100, insbesondere 3 bis 20 betragen.The columns may preferably have at least two, more preferably at least 3 theoretical plates. The number of theoretical plates can, for. B. 2 to 100, in particular 3 to 20.
Das N-Vinyllactam kann im Allgemeinen mit einer Reinheit von mehr als 98 Gew. %, insbesondere mehr als 99 Gew. %, besonders bevorzugt von mehr als 99, 5 Gew. % gewonnen werden.The N-vinyllactam can generally be obtained with a purity of more than 98% by weight, in particular more than 99% by weight, particularly preferably more than 99.5% by weight.
Die Polymerbildung ist beim erfindungsgemäßen Verfahren deutlich verringert. Zur weiteren Verringerung der Polymerbildung können zusätzlich handelsübliche Stabilisa- toren zugesetzt werden, welche eine Polymerisation inhibieren. Die Polymerbildung beim erfindungsgemäßen Verfahren ist jedoch so gering, dass auf einen Zusatz derartiger Stabilisatoren verzichtet werden kann.The polymer formation is significantly reduced in the process according to the invention. To further reduce polymer formation, commercial stabilizers may additionally be added which inhibit polymerization. However, the polymer formation in the process according to the invention is so low that it is possible to dispense with the addition of such stabilizers.
Beispiele:Examples:
Frisch destilliertes N-Vinylpyrrolidon wurde bei 600C unter Stickstoff gelagert.Freshly distilled N-vinylpyrrolidone was stored at 60 ° C. under nitrogen.
Das N-Vinylpyrrolidon enthielt die in der Tabelle angegebenen Stähle in Form von Spänen.The N-vinylpyrrolidone contained the steels in the form of chips given in the table.
Der Polymergehalt (bezogen auf die anfängliche menge N-Vinylpyrrolidon wurde nach 22 Tagen bestimmt.The polymer content (based on the initial amount of N-vinylpyrrolidone was determined after 22 days.
Figure imgf000005_0001
BS: unlegierter Baustahl
Figure imgf000005_0001
BS: unalloyed structural steel
RA4: 80MoCrV 42-16; Gehalt in Gew. %: C: 0,77 -0.85RA4: 80MoCrV 42-16; Content in wt.%: C: 0.77 -0.85
Mo:3,75-4,5 Cr: 3,75 -4,5Mo: 3.75-4.5 Cr: 3.75 - 4.5
V:0,9-1 ,2V: 0.9-1, 2
(nach Stahlschlüssel, Verlag Stahlschlüssel Wegst GmbH, Autor C.W.Wegst, 2001 , ISBN 3-922599-17-6)(after steel key, publishing house steel key Wegst GmbH, author C.W.Wstst, 2001, ISBN 3-922599-17-6)
80MoCrV 42-16 ist eine vereinfachte Angabe der Zusammensetzung für niedrig legierte Stähle: 80 : 0,8 % C (80=0,8x100); 42: 4,2% Mo (42= 4,2x10), 16: 4%Cr (16=4x4) 80MoCrV 42-16 is a simplified specification of composition for low alloy steels: 80: 0.8% C (80 = 0.8x100); 42: 4.2% Mo (42 = 4.2x10), 16: 4% Cr (16 = 4x4)

Claims

Patentansprüche claims
1. Verfahren zur Herstellung von N-Vinyllactamen durch Umsetzung von Lactamen mit Acetylen und anschließende Aufarbeitung des erhaltenen Gemischs, da- durch gekennzeichnet, dass Vorrichtungen, die mit N-Vinyllactamen bei einer1. A process for the preparation of N-vinyl lactams by reacting lactams with acetylene and subsequent work-up of the resulting mixture, characterized in that devices containing N-vinyl lactams in a
Temperatur größer 30 0C in Kontakt kommen, aus Edelstahl sind.Temperature greater than 30 0 C come into contact, are made of stainless steel.
2. Verfahren gemäß Anspruch 1 , dadurch gekennzeichnet, dass es sich um einen Edelstahl handelt, der insgesamt mehr als 5 Gew. % Legierungsmetallen, aus- gewählt aus Molybdän, Chrom, Cobalt, Mangan, Nickel, Vanadium, Niob, Tantal,2. The method according to claim 1, characterized in that it is a stainless steel, the total of more than 5 wt.% Alloy metals selected from molybdenum, chromium, cobalt, manganese, nickel, vanadium, niobium, tantalum,
Titan, Zirkonium, Aluminium und Blei, enthält.Titanium, zirconium, aluminum and lead.
3. Verfahren gemäß Anspruch 1 oder 2, dadurch gekennzeichnet, dass es sich um einen Edelstahl handelt, der mehr als 5 Gew. % Legierungsmetalle, ausgewählt aus Molybdän, Chrom, Vanadium und Nickel, enthält.3. The method according to claim 1 or 2, characterized in that it is a stainless steel containing more than 5 wt.% Alloy metals selected from molybdenum, chromium, vanadium and nickel.
4. Verfahren gemäß einem der Ansprüche 1 bis 3, dadurch gekennzeichnet, dass es sich um einen Edelstahl handelt, der mindestens 1 Gew. % Molybdän und mindestens 1 Gew. % Chrom enthält.4. The method according to any one of claims 1 to 3, characterized in that it is a stainless steel containing at least 1 wt.% Molybdenum and at least 1 wt.% Chromium.
5. Verfahren gemäß einem der Ansprüche 1 bis 4, dadurch gekennzeichnet, dass es sich bei den Vorrichtungen, welche mit N-Vinyllactamen bei einer Temperatur größer 300C in Kontakt kommen, um Kolonnen, Behälter, Abscheider, Kondensatoren, Verdampfer und Rohrleitungen handelt5. The method according to any one of claims 1 to 4, characterized in that it is in the devices which come in contact with N-vinyl lactams at a temperature greater than 30 0 C, columns, vessels, separators, condensers, evaporators and pipelines
6. Verfahren gemäß einem der Ansprüche 1 bis 5, dadurch gekennzeichnet, dass es sich bei dem Lactam um 2- Pyrrolidon (gamma-Butyrolactam) und bei dem N- Vinyllactam um N-Vinylpyrrolidon handelt6. Process according to one of claims 1 to 5, characterized in that the lactam is 2-pyrrolidone (gamma-butyrolactam) and N-vinyllactam is N-vinylpyrrolidone
7. Verfahren gemäß einem der Ansprüche 1 bis 6, dadurch gekennzeichnet, dass es kontinuierlich durchgeführt wird.7. The method according to any one of claims 1 to 6, characterized in that it is carried out continuously.
8. Verfahren gemäß einem der Ansprüche 1 bis 7, dadurch gekennzeichnet, dass es ohne Zusatz sonstiger Stabilisatoren durchgeführt wird8. The method according to any one of claims 1 to 7, characterized in that it is carried out without the addition of other stabilizers
9. Verfahren gemäß einem der Ansprüche 1 bis 8, dadurch gekennzeichnet, dass nach der Umsetzung von Acetylen mit dem Lactam eine Aufarbeitung durch Destillation erfolgt und das N-Vinyllactam in einer Reinheit von mehr als 98 Gew. % gewonnen wird 9. The method according to any one of claims 1 to 8, characterized in that after the reaction of acetylene with the lactam, a work-up by distillation and the N-vinyl lactam in a purity of more than 98 wt.% Is recovered
PCT/EP2009/056710 2008-06-12 2009-06-02 Method for producing n-vinylpyrrolidone in a stainless steel reactor WO2009150075A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP08158088 2008-06-12
EP08158088.8 2008-06-12

Publications (1)

Publication Number Publication Date
WO2009150075A1 true WO2009150075A1 (en) 2009-12-17

Family

ID=40940273

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/EP2009/056710 WO2009150075A1 (en) 2008-06-12 2009-06-02 Method for producing n-vinylpyrrolidone in a stainless steel reactor

Country Status (1)

Country Link
WO (1) WO2009150075A1 (en)

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1695096A1 (en) * 1965-11-19 1970-12-10 Gaf Corp N-vinyl lactams, their homo- and copolymers, and processes for their production
DE19839565A1 (en) * 1997-04-09 2000-03-02 Maruzen Petrochem Co Ltd N-vinyl-lactam(s) production
WO2006118319A1 (en) * 2005-04-28 2006-11-09 Nippon Shokubai Co., Ltd. Method for storing n-alkenyl carboxylic acid tertiary amide

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE1695096A1 (en) * 1965-11-19 1970-12-10 Gaf Corp N-vinyl lactams, their homo- and copolymers, and processes for their production
DE19839565A1 (en) * 1997-04-09 2000-03-02 Maruzen Petrochem Co Ltd N-vinyl-lactam(s) production
WO2006118319A1 (en) * 2005-04-28 2006-11-09 Nippon Shokubai Co., Ltd. Method for storing n-alkenyl carboxylic acid tertiary amide

Similar Documents

Publication Publication Date Title
DE3331877A1 (en) METHOD FOR PRODUCING A POLYPROPYLENE MOLD
DE2526381B2 (en) Process for the production of glycolic acid or mixtures thereof with diglycolic acid
DE2352980B2 (en) Process for the production of crystalline propene-ethene-butene-1 terpolymers
DE60003137T2 (en) Process for the recovery of N-vinyl-2-pyrrolidone
DE1952781C3 (en) Process for the preparation of carbonyl compounds
EP2922819B1 (en) Method for purifying n-alkylpyrrolidones
DE2922545C2 (en) Process for the production of tert-butanol
DE2826548C2 (en)
WO2009150075A1 (en) Method for producing n-vinylpyrrolidone in a stainless steel reactor
EP2602247B1 (en) Method for purifying N-alkyl substituted pyrrolidones through hydration
DE69910692T2 (en) Titanium-vanadium mixed catalysts for ethylene solution polymerization
DE1693027B2 (en) Process for the production of e-caprolactone or methyli-caprolactones
DE3413212C1 (en) Process for the preparation of anhydrous potassium tert-butoxide
DE1745375A1 (en) Process for the preparation of homopolymers and copolymers of ethylene and a suitable catalyst
DE3027350C2 (en) Block interpolymerization process
EP0961768B1 (en) Method for separating 6-aminocaproic acid nitrile from mixtures containing 6-aminocaproic acid nitrile and an imine
WO2009071479A1 (en) Method for producing n-vinyl pyrrolidone from lactone-free pyrrolidone
DE2832876A1 (en) METHOD FOR HALOGENATING ALDEHYDE
EP2070912B1 (en) Method for the vinylation of amides
DE1952780C3 (en) Process for the dehydrogenation of an alkane, a cycloalkane, a monohalosubstituted alkane or mixtures thereof
DE2361988C3 (en) Process for the production of aluminum trialkyls
WO2018036848A1 (en) Vinylation with acetylene in the presence of water
DE19509362A1 (en) Process for the preparation of N-vinyl lactams
DE102009013786A1 (en) Process for producing decafluorocyclohexane
DE2057521A1 (en) Reppe-type catalytic carbonylation process

Legal Events

Date Code Title Description
121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 09761638

Country of ref document: EP

Kind code of ref document: A1

NENP Non-entry into the national phase

Ref country code: DE

122 Ep: pct application non-entry in european phase

Ref document number: 09761638

Country of ref document: EP

Kind code of ref document: A1