EP0956279A1 - Procede d'esterification d'acide (meth)acrylique avec un alcanol - Google Patents

Procede d'esterification d'acide (meth)acrylique avec un alcanol

Info

Publication number
EP0956279A1
EP0956279A1 EP98904042A EP98904042A EP0956279A1 EP 0956279 A1 EP0956279 A1 EP 0956279A1 EP 98904042 A EP98904042 A EP 98904042A EP 98904042 A EP98904042 A EP 98904042A EP 0956279 A1 EP0956279 A1 EP 0956279A1
Authority
EP
European Patent Office
Prior art keywords
meth
acrylic acid
product
acid
oligomeric
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.)
Granted
Application number
EP98904042A
Other languages
German (de)
English (en)
Other versions
EP0956279B1 (fr
Inventor
Heinrich Aichinger
Michael Fried
Gerhard Nestler
Holger Herbst
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 EP0956279A1 publication Critical patent/EP0956279A1/fr
Application granted granted Critical
Publication of EP0956279B1 publication Critical patent/EP0956279B1/fr
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/30—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group
    • C07C67/317—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by splitting-off hydrogen or functional groups; by hydrogenolysis of functional groups
    • C07C67/327—Preparation of carboxylic acid esters by modifying the acid moiety of the ester, such modification not being an introduction of an ester group by splitting-off hydrogen or functional groups; by hydrogenolysis of functional groups by elimination of functional groups containing oxygen only in singly bound form
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/48—Separation; Purification; Stabilisation; Use of additives
    • C07C67/60—Separation; Purification; Stabilisation; Use of additives by treatment giving rise to chemical modification

Definitions

  • the present invention relates to a process for the esterification of (meth) acrylic acid with an alkanol in the presence of an esterification catalyst, in which unreacted starting compounds and the (meth) acrylic acid ester to be formed are separated off from the reaction mixture, leaving a bottom product containing oxyester, and either
  • the oxyesters are first separated from the bottom product by distillation, the distillate is mixed with monomeric and / or oligomeric (meth) acrylic acid and then, in the presence of acid catalysts different from monomeric and oligomeric (meth) acrylic acid, the oxyesters contained therein are cleaved by the action of elevated temperature .
  • (meth) acrylic acid denotes in a known manner acrylic or methacrylic acid.
  • oligomeric (meth) acrylic acid means the Michael adducts of (meth) acrylic acid with itself and the resulting products. Such Michael adducts can be represented by the general formula (III)
  • Oligomeric (meth) acrylic acid is obtained, for example, in the distillation of (for example, crude) (meth) acrylic acid (the term "crude” indicates a small amount of, in particular, aldehydic impurities still present) in the sump (see, for example, DE-A-22 35 326).
  • alkyl esters of (meth) acrylic acid are important starting compounds for the preparation of polymers produced by free-radical polymerization, which e.g. find use as adhesives.
  • Alkyl esters of (meth) acrylic acid are usually prepared by esterification of (meth) acrylic acid with alkanols at elevated temperature in the liquid phase with or without solvent and in the presence of acids other than (meth) acrylic acid as a catalyst (cf., for example, DE-A 23 39 519).
  • the disadvantage of this method of preparation is that under the aforementioned esterification conditions, unreacted starting alcohol forms as side reactions to form a compound of the general formula I listed below and unreacted (meth) acrylic acid to form a compound of the general formula II on the ethylenically unsaturated double bond of already formed (meth) acrylic acid - alkyl ester added (Michael addition).
  • the oxyester formation takes place in low to a lesser extent.
  • the formation of oxyesters is described in DE-A 23 39 529, among others. The above publication confirms that the formation of oxyesters takes place essentially independently of the special esterification conditions.
  • Any esterification reaction mixture is usually worked up in such a way that unreacted starting compounds and the target ester are separated from the reaction mixture by distillation, the acid catalyst used for the esterification possibly being separated beforehand by extraction with water and / or aqueous alkali (cf., for example, Ullmann's Encyclopedia of Industrial Chemistry, Vol.AI, 5th Ed., VCH p. 167ff).
  • the bottom product remaining in the course of such a work-up by distillation contains the oxyesters, which cause a considerable loss in yield.
  • JP-A-82/62229 describes the alkaline saponification of the high-boiling esterification residue. Although part of the alcohol and acrylic acid and ⁇ -hydroxypropionic acid used are obtained in this way, their simple and economical recycling into the esterification reaction is not possible owing to their salt content which can be attributed to the alkaline saponification conditions, which is a disadvantage.
  • JP-AS-72/15936 relates to the reaction of ⁇ -alkoxypropionic acid esters with acrylic acid in the presence of strong acids to obtain acrylic acid esters (transesterification).
  • acrylic acid esters transesterification
  • ⁇ -alkoxypropionic acid is obtained in an equimolar amount, which could not be returned to the (meth) acrylic acid esterification.
  • a disadvantage of this procedure is that the conversion is only about 30%.
  • JP-A-94/65149 describes the cleavage of Michael addition products I and II in the presence of titanium alcoholates.
  • the comparatively low ( ⁇ 60%) turnover and the need for titanates are disadvantageous here.
  • GB-PS 923 595 discloses working up the residue of the esterification of acrylic acid with alkanols in the absence of molecular oxygen. We recommend the removal of all escaping monomers before the cleavage, the cleavage in the presence of sulfuric acid and the removal of the cleavage products with the aid of an inert gas stream. According to the exemplary embodiments, the cleavage is carried out at at least 300 ° C. Carbon is formed as a residue, which must be removed mechanically from the reactor. Therefore, this procedure can not be carried out economically or on an industrial scale.
  • CN-A 1,063,678 describes the cleavage of the alkoxypropionic acid ester contained in the esterification residue in the presence of sulfuric acid in a cascade, the temperature and catalyst concentration being different in each reactor. Coupled with the cleavage is a distillation to separate alkanol and acrylate. The process is very cumbersome and does not achieve high sales.
  • CN-A 1,058,390 relates to the splitting of alkoxypropionic acid esters in the presence of sulfuric acid etc. into alkanols and acrylic acid esters. This is done step by step. The cleavage is first carried out under reflux and then the reaction products are distilled off. The splitting of the acrylic acid-containing ester residues from ethyl / methyl acryl production (ethyl ethoxypropionate, methyl methoxypropionate) is carried out in the presence of ethanol or methanol. This too
  • DE-A 19547459 and DE-A 19547485 relate to the cleavage of the oxyesters in the presence of monomeric or oligomeric (meth) acrylic acid and in the presence of acids other than the aforementioned acids.
  • the formation of the undesired cleavage by-products can be reduced significantly as a result, but the reaction rate is unsatisfactory.
  • US Pat. No. 3,227,746 proposes the cleavage of alkoxypropionic acid alkyl esters in the presence of dehydration catalysts and water.
  • a presence of monomeric or oligomeric (Meth) acrylic acid is not included.
  • butoxypropionic acid butyl ester is 85% in the presence of 100% by weight (with respect to oxyester).
  • - Split phosphoric acid and 10 wt .-% (with respect to oxyester) water According to the teaching of US Pat. No. 3,227,746, the presence of the water renders the presence of alkanol superfluous and prevents unreacted alkyl alkoxypropionate from being converted into the distillate.
  • the disadvantage of this procedure is the high amount of catalyst used. Furthermore, the reaction rate is just as unsatisfactory as the formation of cleavage by-products.
  • the invention was therefore based on the object of performing the cleavage of the oxyesters formed in the esterification of (meth) acrylic acid with an alkanol in a more advantageous manner than in the prior art and integrating them into the esterification process.
  • the oxyesters are first separated from the bottom product by distillation, the distillate is mixed with monomeric and / or oligomeric (meth) acrylic acid and then, in the presence of acid catalysts different from monomeric and oligomeric (meth) acrylic acid, the oxyesters contained therein are cleaved by the action of elevated temperature ,
  • oligomeric (meth) acrylic acid As a rule, based on the oxyesters to be cleaved, 5 to 50% by weight, preferably 10 to 40% by weight, of monomeric and / or oligomeric (meth) acrylic acid are added.
  • the monomeric and / or oligomeric (meth) acrylic acid is normally added in form known per se, stabilized by means of polymerization inhibitors.
  • the oligomeric (meth) acrylic acid used advantageously is the sump obtained in the purification of crude (meth) acrylic acid by distillation, which mainly contains compounds of the general formula III.
  • the monomeric (meth) acrylic acid and / or the (meth) acrylic acid oligomers can be added to the mixture to be cleaved before the cleavage. However, they can also be fed separately to the cleavage reactor.
  • the amount of water to be added for the cleavage, based on the oxyesters to be cleaved, is generally 0.1 to 20% by weight, preferably 1 to 10% by weight.
  • the method is carried out in the presence of molecular oxygen.
  • acidic esterification catalyst which may also be present and which is different from monomeric and oligomeric (meth) acrylic acid
  • the total amount of acid then contained, different from monomeric and oligomeric (meth) acrylic acid, can be 1 to
  • a stripping gas which preferably contains molecular oxygen is passed through the product to be cleaved as an entrainer for the cleavage products in the process according to the invention.
  • Stripping gas air or mixtures of air with inert gas (eg nitrogen) are used.
  • the distillation conditions depend on the type of alcohol component used in the esterification. As a rule, a temperature of 100 to 300 ° C and a pressure of 1 to 50 mbar are provided. Any conventional distillation apparatus is suitable for the distillation process. Since only a simple separation task has to be solved, a simple splash guard is usually sufficient, i.e. a column is normally not required.
  • a simple heatable stirred reactor with double-wall heating or heating coil or else a forced-circulation evaporator, for example a falling-film evaporator or flat evaporator, coupled with a residence time container, can be used for the inventive workup of the oxyesters obtained in the bottom product during the esterification in the bottom product or of the oxyester distillate separated from the esterification bottom.
  • a rectification device placed on the cleavage apparatus e.g. a packed column, packed column or tray column is appropriate. This rectification device is usually operated stabilized with polymerization inhibitors (e.g. phenothiazine, hydroquinone monomethyl ether, etc.).
  • Typical conditions for carrying out the process according to the invention of cleaving the oxyesters obtained in the esterification in the bottom product or separated off from the bottom product are as follows:
  • Catalyst at least one acid from the group comprising mineral acids, such as sulfuric acid and phosphoric acid, and organic acids other than (meth) acrylic acid, such as alkyl or Arylsulfonic acids, for example methanesulfonic acid or p-toluenesulfonic acid
  • mineral acids such as sulfuric acid and phosphoric acid
  • organic acids other than (meth) acrylic acid such as alkyl or Arylsulfonic acids, for example methanesulfonic acid or p-toluenesulfonic acid
  • Amount of catalyst 1 - 20% by weight, preferably 5 -
  • Amount of (meth) acrylic acid 5-50% by weight, preferably 10-40
  • Amount of water 0.1-20% by weight, preferably 1-10% by weight, based on the amount of the bottom product or on the amount of the oxyester-distillate separated from the bottom product
  • Pressure preferably unpressurized or reduced pressure (so that the fission products evaporate immediately)
  • the reaction is carried out, for example, in such a way that the bottom product to be cleaved is continuously discharged from the work-up of the esterification mixture by distillation and fed to the cleavage reactor with the cleavage catalyst, the water and the monomeric and / or oligomeric (meth) acrylic acid.
  • the reaction can also be carried out batchwise.
  • a semi-continuous reac ⁇ tion guidance is possible, in which the product to be cleaved, of water and the monomeric and / or oligomeric (meth) acrylic acid continuously to the cleavage reactor which contains the cleavage catalyst, is fed to the bottom roduct only after the cleavage from the Cleavage reactor is removed batchwise.
  • the Fission products are continuously separated off by distillation and expediently returned to the esterification.
  • the esterification is carried out in such a way that the water formed during the esterification is continuously separated off via a rectification column attached to the esterification reactor, the cleavage products are preferably returned to the esterification via this rectification column (it is expedient to recycle into the lower half of the rectification column).
  • the monomeric and / or oligomeric (meth) acrylic acid and the water can be fed to the cleavage reactor separately or together or else as a mixture with the product to be cleaved.
  • esters are prepared by the customary processes (see Ullmann's Encyclopedia of Industrial Chemistry, Vol. AI, 5th Ed., VCH, p. 167ff).
  • Catalyst sulfuric acid or sulfonic acids (e.g. p-toluenesulfonic acid)
  • Amount of catalyst 0.1-10% by weight (preferably 0.5-5% by weight) with regard to starting materials
  • Reaction temperature 80 160 ° C, preferably 90 - 130 ° C
  • an entrainer eg cyclohexane or toluene
  • the esterification can be carried out either continuously or batchwise without pressure, with positive or negative pressure.
  • the bottom product resulting from the removal of the acidic esterification catalyst, the unreacted starting materials and the acrylic ester generally has the following composition:
  • alkoxypropionates see formula I
  • acyloxypropionates see formula II
  • a circulation reactor made of glass (volume: 1 1), heated with a heating plug, was filled with 500 g of an oxyester distillate, obtained from the esterification residue freed from the acidic esterification catalyst, and 40 g of p-toluenesulfonic acid.
  • the oxyester distillate contained
  • the gap temperature was 195 ° C and the working pressure was
  • the esterification residue to be cleaved was fed continuously to the cleavage reactor during level cleavage.
  • the cleavage products were removed in vapor form and condensed at the top of the column (50 cm ⁇ 2.8 cm, empty) placed on the cleavage reactor. Within 119.5 hours, 7401 g of mixture (62 g / h) were fed to the cleavage and 7080 g of cleavage products were condensed. According to the gas chromatographic analysis, the condensate contained:
  • the gap temperature was 195 ° C, the working pressure 1 atm.
  • the oxyester distillate to be cleaved 20% by weight of acrylic acid and water (4% by weight, based on oxyester distillate) were fed continuously to the cleavage reactor.
  • the cleavage products were condensed at the top of the column placed on the reactor (50 cm ⁇ 2.8 cm, empty).

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • General Chemical & Material Sciences (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)

Abstract

L'invention concerne un procédé d'estérification d'acide (méth)acrylique avec un alcanol, selon lequel les oxyesters produits en tant que produit secondaire de l'estérification sont soumis à leur tour à un clivage sous catalysation acide, par addition d'acide (méth)acrylique monomère et/ou oligomère et d'eau.
EP98904042A 1997-01-20 1998-01-08 Procede d'esterification d'acide (meth)acrylique avec un alcanol Expired - Lifetime EP0956279B1 (fr)

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
DE19701737A DE19701737A1 (de) 1997-01-20 1997-01-20 Verfahren zum Verestern von (Meth)acrylsäure mit einem Alkanol
DE19701737 1997-01-20
PCT/EP1998/000068 WO1998031656A1 (fr) 1997-01-20 1998-01-08 Procede d'esterification d'acide (meth)acrylique avec un alcanol

Publications (2)

Publication Number Publication Date
EP0956279A1 true EP0956279A1 (fr) 1999-11-17
EP0956279B1 EP0956279B1 (fr) 2002-08-28

Family

ID=7817791

Family Applications (1)

Application Number Title Priority Date Filing Date
EP98904042A Expired - Lifetime EP0956279B1 (fr) 1997-01-20 1998-01-08 Procede d'esterification d'acide (meth)acrylique avec un alcanol

Country Status (9)

Country Link
US (1) US20010047106A1 (fr)
EP (1) EP0956279B1 (fr)
JP (1) JP2001508076A (fr)
KR (1) KR20000070185A (fr)
CN (1) CN1244189A (fr)
AU (1) AU6207798A (fr)
BR (1) BR9806781A (fr)
DE (2) DE19701737A1 (fr)
WO (1) WO1998031656A1 (fr)

Families Citing this family (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19851984A1 (de) * 1998-11-11 2000-05-18 Basf Ag Verfahren zum Verestern von (Meth)acrylsäure mit einem Alkanol
EP1163201B1 (fr) 1999-03-06 2003-08-20 Basf Aktiengesellschaft Procede de production d'acide acrylique
DE19922722A1 (de) * 1999-05-18 2000-11-23 Basf Ag Verfahren zur Herstellung von (Meth)acrylsäureestern
DE10127941A1 (de) 2001-06-08 2002-05-29 Basf Ag Verfahren zur Herstellung von (Meth)acrylsäureestern
AU2002355041A1 (en) * 2001-11-28 2003-06-10 Mitsubishi Chemical Corporation Process for producing (meth)acrylic acid compound
AU2002354469A1 (en) * 2001-12-26 2003-07-24 Mitsubishi Chemical Corporation Method of decomposing by-product of (meth)acrylic ester production
DE102004008575A1 (de) * 2004-02-19 2005-09-08 Stockhausen Gmbh Spaltung oligomerer (Meth)acrylsäure in flüssiger Phase unter Druck
DE102008054587A1 (de) 2008-12-12 2010-06-17 Basf Se Verfahren zur Rückspaltung von in einer Flüssigkeit F enthaltenen Michael-Addukten, die bei der Herstellung von Acrylsäure oder deren Ester gebildet wurde
CN110372509A (zh) * 2019-07-19 2019-10-25 江门谦信化工发展有限公司 一种丙烯酸正丁酯重组分的裂解回收工艺
EP4146618A1 (fr) 2020-05-04 2023-03-15 Basf Se Procédé de décomposition d'adduits de michael contenus dans un fluide f et formés au cours de la préparation d'acide acrylique
EP4015498B1 (fr) 2020-12-18 2024-04-24 Basf Se Procédé de production continue d'acide acrylique-n-butylester
FR3146894A1 (fr) 2023-03-24 2024-09-27 Arkema France Procede de purification d’acrylates d’alkyle legers

Family Cites Families (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
BE626622A (fr) * 1961-12-29
DE19547459A1 (de) * 1995-12-19 1996-07-25 Basf Ag Verfahren zum Verestern von (Meth)acrylsäure mit einem Alkanol
DE19547485A1 (de) * 1995-12-19 1996-05-09 Basf Ag Verfahren zum Verestern von (Meth)acrylsäure mit einem Alkanol

Non-Patent Citations (1)

* Cited by examiner, † Cited by third party
Title
See references of WO9831656A1 *

Also Published As

Publication number Publication date
CN1244189A (zh) 2000-02-09
DE59805307D1 (de) 2002-10-02
BR9806781A (pt) 2000-05-16
KR20000070185A (ko) 2000-11-25
DE19701737A1 (de) 1998-07-23
WO1998031656A1 (fr) 1998-07-23
EP0956279B1 (fr) 2002-08-28
US20010047106A1 (en) 2001-11-29
AU6207798A (en) 1998-08-07
JP2001508076A (ja) 2001-06-19

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