EP4376970A1 - Verfahren zur kontinuierlichen destillation von acrylaten - Google Patents

Verfahren zur kontinuierlichen destillation von acrylaten

Info

Publication number
EP4376970A1
EP4376970A1 EP22761052.4A EP22761052A EP4376970A1 EP 4376970 A1 EP4376970 A1 EP 4376970A1 EP 22761052 A EP22761052 A EP 22761052A EP 4376970 A1 EP4376970 A1 EP 4376970A1
Authority
EP
European Patent Office
Prior art keywords
weight
rectification column
feed
acrylate
evaporator
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.)
Pending
Application number
EP22761052.4A
Other languages
German (de)
English (en)
French (fr)
Inventor
Tile GIESHOFF
Marvin KRAMP
Cornelis Hendricus DE RUITER
Karl-Friedrich SCHNEIDER
Felix HUELSMANN
Christian Rein
David ELIXMANN
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 EP4376970A1 publication Critical patent/EP4376970A1/de
Pending legal-status Critical Current

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C67/00—Preparation of carboxylic acid esters
    • C07C67/48—Separation; Purification; Stabilisation; Use of additives
    • C07C67/52—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
    • C07C67/54—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
    • B01D3/14—Fractional distillation or use of a fractionation or rectification column
    • B01D3/32—Other features of fractionating columns ; Constructional details of fractionating columns not provided for in groups B01D3/16 - B01D3/30
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B01—PHYSICAL OR CHEMICAL PROCESSES OR APPARATUS IN GENERAL
    • B01D—SEPARATION
    • B01D3/00—Distillation or related exchange processes in which liquids are contacted with gaseous media, e.g. stripping
    • B01D3/14—Fractional distillation or use of a fractionation or rectification column
    • B01D3/32—Other features of fractionating columns ; Constructional details of fractionating columns not provided for in groups B01D3/16 - B01D3/30
    • B01D3/322—Reboiler specifications
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C57/00—Unsaturated compounds having carboxyl groups bound to acyclic carbon atoms
    • C07C57/52—Unsaturated compounds having carboxyl groups bound to acyclic carbon atoms containing halogen
    • C07C57/54—Halogenated acrylic or methacrylic acids
    • C—CHEMISTRY; METALLURGY
    • C07—ORGANIC CHEMISTRY
    • C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
    • C07C69/00—Esters of carboxylic acids; Esters of carbonic or haloformic acids
    • C07C69/52—Esters of acyclic unsaturated carboxylic acids having the esterified carboxyl group bound to an acyclic carbon atom
    • C07C69/533—Monocarboxylic acid esters having only one carbon-to-carbon double bond
    • C07C69/54—Acrylic acid esters; Methacrylic acid esters

Definitions

  • the present invention relates to a process for the continuous distillation of acrylates using a rectification column, characterized in that the content of acrylate in the feed to the rectification column is at least 80% by weight, the liquid in the bottom region of the rectification column is heated by means of an evaporator and the product-contact Parts of the evaporator are made of stainless steel.
  • polymers or copolymers produced on the basis of acrylates are of great economic importance in the form of polymer dispersions. They are used, for example, as adhesives, paints or textile, leather and paper auxiliaries.
  • JP H01 -180850 A describes the influence of surface roughness on polymer formation in distillation columns.
  • JP 2001-213844 A describes the production of acrylates and methacrylates.
  • alloys of 6 to 20% by weight nickel, 14 to 24% by weight chromium and 0.5 to 5.5% by weight cobalt are proposed.
  • WO 2005/040084 A1 describes the use of alloys with sufficient copper to avoid the polymerization of ethylenically unsaturated monomers.
  • Acrylates are usually made by esterification of acrylic acid.
  • the acrylates obtained in the reaction are then distilled.
  • rectification columns with evaporators made of non-alloy steel are used.
  • Solid deposits form on the evaporator surfaces, which impede heat transfer and can even lead to blockages. These deposits of solid matter must be removed mechanically at regular intervals.
  • the object was therefore to find an improved process for the distillation of acrylates, in particular with less solid matter in the evaporators used.
  • the object is achieved by a process for the continuous distillation of acrylates by means of a rectification column, characterized in that the content of acrylate in the feed of the rectification column is at least 80% by weight, the liquid in the bottom area of the Rectification column is heated by an evaporator and the parts of the evaporator that come into contact with the product are made of stainless steel.
  • Suitable acrylates are methyl acrylate, ethyl acrylate, n-butyl acrylate and 2-ethylhexyl acrylate.
  • Acrylates are also referred to as acrylic acid esters.
  • the content of acrylate in the feed to the rectification column is preferably at least 85% by weight, very particularly preferably at least 90% by weight, very particularly preferably at least 95% by weight.
  • the feed to the rectification column preferably has an acid number of less than 100 mg potassium hydroxide per g feed, particularly preferably less than 10 mg potassium hydroxide per g feed, very particularly preferably less than 1 mg potassium hydroxide per g feed.
  • 1 g of feed is diluted with 100 ml of ethanol and titrated with 0.1 mole potassium hydroxide in ethanol against phenolphthalein.
  • the rectification column is of a type known per se and consists of the actual column body with the separating internals, an evaporator in the bottom region of the rectification column and a condenser in the top region of the rectification column.
  • feed is continuously metered into the rectification column and continuously distilled acrylate is drawn off.
  • all common internals can be considered as separating internals, for example trays, packings and/or beds.
  • Preferred trays are bubble-cap trays, sieve trays, valve trays, Thormann trays and/or dual-flow trays, and beds with rings, spirals, saddle bodies, Raschig, Intos or Pall rings, barrel or Intalox saddles are preferred , Top-Pak etc. or braids preferred.
  • the evaporator is of a type known per se.
  • the heat transfer from the evaporator to the liquid to be evaporated takes place at the parts of the evaporator that come into contact with the product.
  • Suitable evaporators are, for example, tube bundle heat exchangers.
  • a tube bundle heat exchanger consists of a jacket space and a tube space.
  • the heating medium flows through the jacket space. In the case of evaporators, this is usually heating steam that condenses on the outside of the tube in the jacket space.
  • the liquid to be evaporated flows through the tube space, which consists of many tubes.
  • the insides of the tubes are the parts of the evaporator that come into contact with the product.
  • the tube bundle heat exchanger can be operated as an internal or external evaporator.
  • An internal evaporator is located directly below the separating internals in the rectification column.
  • An external evaporator is located next to the rectification column and is connected to the lower section of the rectification column.
  • the circulation through an external evaporator can be boosted by a pump (forced circulation evaporator).
  • a pressure control valve can be installed in the return line of a forced circulation evaporator. This avoids boiling in the tube bundle heat exchanger and only vaporizes when it is expanded in the lower region of the rectification column (forced circulation expansion evaporator). The latter is particularly gentle.
  • the capacitor is also of a type known per se.
  • the capacitor can be operated as an internal or external capacitor.
  • An external condenser is located next to the rectification column and is connected to the top of the rectification column.
  • Ge suitable condensers are, for example, shell and tube heat exchangers.
  • a tube bundle heat exchanger consists of a jacket space and a tube space. The cooling medium flows through the jacket space. The gas to be condensed flows through the tube space, which consists of many tubes. Part of the condensed gas is returned to the rectification column as reflux.
  • the parts of the evaporator that come into contact with the product are made of stainless steel.
  • Stainless steels within the meaning of this invention are steels with iron as the main component and at least 10.5% by weight of chromium.
  • the preferred stainless steels preferably contain 10.5 to 30.0% by weight, preferably 16.0 to 26% by weight, particularly preferably 17.0 to 20.5% by weight, very particularly preferably 18 0 to 20.0% by weight, chromium and particularly preferably additionally preferably 2.0 to 35.0% by weight, preferably 8.0 to 26.0% by weight, particularly preferably 10.0 to 25.0% by weight %, very particularly preferably 12.0 to 24.0% by weight, nickel and/or additionally preferably 0.1 to 8.0% by weight, preferably 2.0 to 5.0% by weight, particularly preferably 2.5 to 4.5% by weight, very particularly preferably 3.0 to 4.0% by weight, molybdenum.
  • the present invention is based on the finding that the use of stainless steels can significantly reduce the formation of solid deposits.
  • Acrylates are produced in many ways in a manner known per se by esterifying acrylic acid with an alcohol, e.g. an alkanol. Acrylates are generally obtained via a homogeneously or heterogeneously catalyzed esterification, as for example in Kirk Othmer, Encyclopedia of Chemical Technology, 4th Ed., 1994, pages 301-302 and Ullmann's Encyclopedia of Industrial Chemistry, 5th Edition, Volume A1 , pages 167-169.
  • the literature contains numerous processes for preparing acrylates by esterifying acrylic acid with an alcohol, for example in DE 19604252 A1 and DE 19604253 A1.
  • a process for preparing n-butyl acrylate by acid-catalyzed esterification of acrylic acid with n-butanol is disclosed, for example, in WO 98/52904.
  • EP 0890568 A1 is mentioned as an example of a discontinuous acid-catalyzed esterification.
  • the alcohol used is usually any alcohol containing 1 to 12 carbon atoms, for example monohydric or polyhydric alcohols, preferably monohydric to tetrahydric, particularly preferably monohydric to trihydric, very particularly preferably monohydric or dihydric and in particular monohydric.
  • Examples are methanol, ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, isobutanol, tert-butanol, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol, 1,3-propanediol monomethyl ether, 1,2-propanediol, ethylene glycol, 2, 2-dimethyl-1,2-ethanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, dimethylaminoethanol, n-hexanol, n-heptanol, n-octanol, n-decanol, n-dodecanol, 2-ethylhexanol, 3-methylpentane-1,5-diol, 2-ethylhexane-1,3-dio
  • Preferred alcohols are methanol, ethanol, n-butanol, isobutanol, sec-butanol, 2-ethylhexyl alcohol, n-octanol and dimethylaminoethanol.
  • Particularly preferred alcohols are methanol, ethanol, n-butanol, 2-ethylhexyl alcohol and dimethylamino alcohol.
  • Very particularly preferred alcohols are methanol, ethanol, n-butanol and 2-ethylhexyl alcohol.
  • the acidic catalysts which can be used are preferably sulfuric acid, p-toluenesulfonic acid, benzenesulfonic acid, dodecylbenzenesulfonic acid, methanesulfonic acid or mixtures thereof; acidic ion exchangers or zeolites are also conceivable.
  • Sulfuric acid, p-toluenesulfonic acid and methanesulfonic acid are particularly preferably used, and sulfuric acid and p-toluenesulfonic acid are very particularly preferred.
  • the catalyst concentration, based on the reaction mixture is, for example, from 1 to 20% by weight, preferably from 5 to 15% by weight.
  • transesterification for the preparation of acrylates from acrylates with alcohols, such as the preparation of dimethylaminoethyl acrylate by transesterification of methyl acrylate with dimethylaminoethanol in EP 0906902 A2.
  • a discontinuous transesterification is e.g. described in EP 1 078913 A2.
  • Titanium alcoholates in particular are proposed as catalysts, the alkyl groups of which are C1-C4-alkyl radicals, for example tetramethyl, tetraethyl, tetraisopropyl, tetrapropyl, tetraisobutyl and tetrabutyl titanate (see EP 1 298867 B1, EP 0960877 A2).
  • Other titanium compounds are also described in DE 101 27939 A1.
  • catalysts i.a. Titanium phenolate (DE 2008618 A1), dibutyltin oxide (EP 0906902 A2), metal chelate compounds of e.g. As hafnium, titanium, zirconium or calcium, alkali metal and magnesium alcoholates, organic tin compounds or calcium and lithium compounds, such as oxides, hydroxides, carbonates or halides are proposed.
  • Suitable polymerization inhibitors can be, for example, N-oxides (nitroxyl or N-oxyl radicals, ie compounds which have at least one >N-0 group), such as 4-Hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl or 4-oxo-2,2,6,6-tetramethylpiperidine-N-oxyl, phenols and naphthols such as p-aminophenol, p-nitrosophenol, 2 -tert-butylphenol, 4-tert-butylphenol, 2,4-di-tert-butylphenol, 2-methyl-4-tert-butylphenol, 2,6-tert-butyl-4-methylphenol or 4- tert-butyl-2,6-dimethylphenol, quinones such as hydroquinone or hydroquinone monomethyl ether, aromatic amines such as N,N-diphenylamine, phenylenediamines such as N,N'-dialkyl-
  • Polymerization is preferably inhibited with phenothiazine, hydroquinone, hydroquinone monomethyl ether, 4-hydroxy-2,2,6,6-tetramethylpiperidine-N-oxyl, 4-oxo-2,2,6,6-tetramethylpiperidine-N-oxyl, 2,6-tert-butyl-4-methylphenol or mixtures thereof.
  • Phenothiazine is very particularly preferably used as the polymerization inhibitor.
  • Ethyl acrylate (99.88% by weight ethyl acrylate, 0.05% by weight isobutyl acrylate, 0.03% by weight N,N'-di-sec-butyl-para-phenylenediamine, 0.01% by weight 4-Hydroxy-2,2,6,6-tetramethyl-piperinidyoxyl) was continuously below the first tray of a rectification column (diameter 1,000 mm, 15 dual-flow trays) with tube bundle heat exchanger (62 m 2 ) in the bottom area and external cooler dosed in the head area.
  • the rectification column was operated at a pressure of 400 mbar.
  • the reflux ratio was 0.2.
  • the reflux was stabilized with 4-hydroxy-2,2,6,6-tetramethyl-piperinidyoxyl.
  • the feed to the rectification column was 6,094 kg/h. 7,386 kg/h of distillate were removed at the top of the rectification column.
  • the parts of the evaporator that come into contact with the product were made of stainless steel (material 1.4571 according to DIN EN 10088: 16.5 to 18.5% by weight chromium, 10.5 to 13.5% by weight nickel, 2.0 to 2.5 wt% molybdenum, up to 0.7 wt% titanium).
  • the corrosion rate was less than 0.01 mm/a. No polymer deposits were discernible in the evaporator after 100 days.
  • Ethyl acrylate (99.88% by weight ethyl acrylate, 0.05% by weight isobutyl acrylate, 0.03% by weight N,N'-di-sec-butyl-para-phenylenediamine, 0.01% by weight 4-Hydroxy-2,2,6,6-tetramethyl-piperinidyoxyl) was fed continuously to the 39th tray of a rectification column (diameter 1,100 mm, 52 dual-flow trays) with tube bundle heat exchanger (51 m 2 ) in the bottom area and external cooler dosed in the head area.
  • the rectification column was operated at a pressure of 1000 mbar.
  • the reflux ratio was 0.93.
  • the reflux was stabilized with 4-hydroxy-2,2,6,6-tetramethyl-piperinidyoxyl.
  • the feed to the rectification column was 6,399 kg/h. 6,094 kg/h of product were discharged from the bottom of the rectification column.
  • the parts of the evaporator that come into contact with the product were made of non-alloy steel (material 1.0425: up to 0.3% by weight chromium, up to 0.3% by weight nickel, up to 0.08% by weight molybdenum, up to 0.03% by weight % titanium).
  • the corrosion rate was less than 0.01 mm/a.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Organic Chemistry (AREA)
  • Chemical Kinetics & Catalysis (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
  • Vaporization, Distillation, Condensation, Sublimation, And Cold Traps (AREA)
EP22761052.4A 2021-07-29 2022-07-19 Verfahren zur kontinuierlichen destillation von acrylaten Pending EP4376970A1 (de)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
EP21188534 2021-07-29
PCT/EP2022/070157 WO2023006499A1 (de) 2021-07-29 2022-07-19 Verfahren zur kontinuierlichen destillation von acrylaten

Publications (1)

Publication Number Publication Date
EP4376970A1 true EP4376970A1 (de) 2024-06-05

Family

ID=77155543

Family Applications (1)

Application Number Title Priority Date Filing Date
EP22761052.4A Pending EP4376970A1 (de) 2021-07-29 2022-07-19 Verfahren zur kontinuierlichen destillation von acrylaten

Country Status (7)

Country Link
EP (1) EP4376970A1 (zh)
JP (1) JP2024528014A (zh)
KR (1) KR20240041972A (zh)
CN (1) CN117729967A (zh)
CA (1) CA3227565A1 (zh)
TW (1) TW202313551A (zh)
WO (1) WO2023006499A1 (zh)

Family Cites Families (20)

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FR2033441A5 (zh) 1969-02-25 1970-12-04 Ugilor
JP2633277B2 (ja) 1988-01-12 1997-07-23 三菱化学株式会社 不飽和カルボン酸及びそのエステルの精製における重合防止法
DE19604253A1 (de) 1996-02-06 1997-08-07 Basf Ag Verfahren zur kontinuierlichen Herstellung von Alkylestern der (Meth)acrylsäure
DE19604252A1 (de) 1996-02-06 1997-08-07 Basf Ag Verfahren und Vorrichtung zur kontinuierlichen Herstellung von Alkylestern der (Meth)acrylsäure
ATE228109T1 (de) 1997-05-20 2002-12-15 Union Carbide Chem Plastic Verfahren zur raffination von butylacrylat
DE19728898A1 (de) 1997-07-07 1999-01-14 Henkel Kgaa Verfahren zur lösemittelfreien Herstellung von ungesättigten Polyolestern
EP0906902B1 (en) 1997-10-01 2002-08-28 Nippon Shokubai Co., Ltd. A method for the production of an alkylamino (meth)acrylate and apparatus therefor.
FR2777561B1 (fr) 1998-04-21 2000-06-02 Atochem Elf Sa Procede de fabrication en continu de (meth)acrylates de dialkylaminoalkyle
JP4080090B2 (ja) * 1999-02-18 2008-04-23 株式会社日本触媒 易重合性化合物または易重合性化合物含有液の蒸留方法
DE19940622C1 (de) 1999-08-27 2001-05-17 Roehm Gmbh Verfahren zur Herstellung von Di(meth)acrylsäureestern
JP2001081050A (ja) * 1999-09-10 2001-03-27 Nippon Shokubai Co Ltd 易重合性化合物の取り扱い装置および取り扱い方法
JP2001213844A (ja) 2000-02-02 2001-08-07 Toagosei Co Ltd アクリル酸エステルまたはメタアクリル酸エステル製造装置および製造方法
DE10127939A1 (de) 2001-06-08 2002-05-29 Basf Ag Verfahren zur Herstellung von (Meth)acrylsäureestern
CN100589861C (zh) * 2001-08-22 2010-02-17 三菱化学株式会社 容易聚合化合物用蒸馏装置
EP1298867B1 (en) 2001-09-27 2006-05-31 Alcatel Canada Inc. Master-slave communication system and method for a network element
DE10332758A1 (de) * 2003-07-17 2004-05-27 Basf Ag Thermisches Trennverfahren zur Abtrennung wenigstens eines (Meth)acrylmonomere angereichert enthaltenden Stoffstroms
WO2005040084A1 (en) 2003-09-24 2005-05-06 Dow Global Technologies Inc. Metal surfaces to inhibit ethylenically unsaturated monomer polymerization
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DE102004003733A1 (de) * 2004-01-23 2005-08-11 Basf Ag Verfahren zur Herstellung von (Meth)Acrylsäureestern
JP2005336110A (ja) * 2004-05-27 2005-12-08 Mitsubishi Chemicals Corp （メタ）アクリル酸および（メタ）アクリル酸エステルの製造方法

Also Published As

Publication number Publication date
CA3227565A1 (en) 2023-02-02
JP2024528014A (ja) 2024-07-26
TW202313551A (zh) 2023-04-01
KR20240041972A (ko) 2024-04-01
WO2023006499A1 (de) 2023-02-02
CN117729967A (zh) 2024-03-19

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