WO2001010811A1 - Process for the preparation of methyl methacrylate - Google Patents
Process for the preparation of methyl methacrylate Download PDFInfo
- Publication number
- WO2001010811A1 WO2001010811A1 PCT/JP1999/004268 JP9904268W WO0110811A1 WO 2001010811 A1 WO2001010811 A1 WO 2001010811A1 JP 9904268 W JP9904268 W JP 9904268W WO 0110811 A1 WO0110811 A1 WO 0110811A1
- Authority
- WO
- WIPO (PCT)
- Prior art keywords
- methanol
- methyl methacrylate
- methacrolein
- distillation
- reaction mixture
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/39—Preparation of carboxylic acid esters by oxidation of groups which are precursors for the acid moiety of the ester
-
- 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
Definitions
- the present invention relates to a method for recovering methanol by distillation from a reaction mixture containing at least methyl methacrylate and methanol obtained by direct esterification reaction of methacrolein and methanol, and using the recovered methanol as a raw material for the direct esterification reaction.
- the present invention relates to a method for producing methyl methacrylate, which can be used as such.
- Japanese Patent Publication No. 1144754 discloses a method in which a saturated hydrocarbon having 6 to 8 carbon atoms is fed to a distillation column and methanol is recovered. For example, a method has been proposed for separating the files.
- Japanese Patent Application Laid-Open No. 57-97440 discloses that a mixed solution of methanol, water and methyl methacrylate is fed to a distillation column to purify methyl methacrylate by distillation.
- JP-A-58-180457 discloses an azeotropic formation in which a mixture of methanol, water and methyl methacrylate forms an azeotropic mixture with methanol in the presence of methyl methacrylate and water.
- Suitable azeotropic agents at this time include hydrocarbon solvents such as n-hexane, n-octane, cyclohexane, benzol, and toluene, and solvents such as diisopropyl ether, tetrahydrofuran, and dimethyl carbonate.
- Japanese Patent Application Laid-Open No. 7-69948 discloses that a mixture is obtained by adding a hydrocarbon solvent and water to a reaction mixture, and the mixture is separated into two phases, an organic phase and a hydrated methanol phase. Recover methanol by distilling off methanol from the aqueous methanol phase Is disclosed.
- an object of the present invention is to recover methanol by distillation from a reaction mixture containing at least methyl methacrylate and methanol obtained by direct esterification reaction of methacrolein and methanol, and to recover the recovered methanol by the direct esterification reaction.
- a hydrocarbon that needs to be separated and removed later as an azeotropic agent Another object of the present invention is to provide a method capable of reducing the amount of methyl methacrylate contained in the recovered methanol.
- the present invention provides a reaction mixture containing at least methyl methacrylate and methanol by a direct esterification reaction of methacrolein and methanol, and separately adding methacrolein as an azeotropic agent to the reaction mixture.
- a method for producing methyl methacrylate which comprises recovering methanol from a reaction mixture by distillation.
- the recovered methanol can be used as a raw material for producing methyl methacrylate by a direct esterification reaction.
- a method for producing methyl methacrylate by a direct esterification reaction of methacrolein with methanol is not particularly limited, and may be a gas phase or a liquid phase reaction.
- the reaction system is not particularly limited, and may be any system such as a continuous system and a batch system. Specifically, a method of continuously performing a reaction in a liquid phase using a palladium-based catalyst is exemplified.
- the reaction mixture obtained by the direct esterification reaction contains unreacted raw materials and the product methyl methacrylate, but the reaction mixture which is the object of the present invention comprises at least unreacted raw materials. And methyl methacrylate as a product.
- the concentration of methanol-methyl methacrylate contained in the reaction mixture varies depending on the reaction conditions and the like.For example, when the reaction is performed in the liquid phase using a palladium catalyst, the concentration of methanol contained in the reaction mixture is The concentration is usually 25 to 70 weight. / 0 , the concentration of methyl methacrylate is usually 20 to 60% by weight.
- the reaction mixture further contains unreacted raw materials such as methacrolein, by-products such as methyl formate and water.
- the reaction mixture is supplied to a distillation column in advance, and one minute is supplied from the top of the column. Some operations such as distilling off low-boiling by-products together with methanol in part of the methacrine rain.
- methacrolein when methanol is recovered from the reaction mixture by distillation, methacrolein is separately added as an azeotropic agent to the reaction mixture.
- the method of adding methacrolein is not particularly limited.For example, a method of supplying the reaction mixture and methacrolein to appropriate positions in the distillation column, and a method of adding methacrolein to the reaction mixture and then supplying the mixture to the distillation column And the like.
- methanol is removed from the top of the column together with azeotropic methacrolein.
- the amount of methacrolein to be added is preferably 20 to 200 parts by weight, particularly preferably 40 to 80 parts by weight, based on 100 parts by weight of methanol in the reaction mixture. If the amount of methacrolein is less than 20 parts by weight, a large amount of methyl methacrylate may be distilled out during the recovery of methanol, making it difficult to recover methanol. The excess methacrolein is recycled to the reactor, In some cases, the ratio of methanol to methacrolein cannot be controlled within an appropriate range, adverse effects on the reaction may occur, and methacrolein may be polymerized.
- the type of distillation column used for recovering methanol is not particularly limited, and for example, a known type such as a tray type or a packed column type can be used.
- a decanter may be provided to separate and take out water.
- the distillation conditions are not particularly limited, but the distillation pressure is preferably normal pressure or reduced pressure, and the bottom temperature is preferably 120 ° C. or lower to prevent polymerization.
- methacrolein is contained in methanol recovered by distillation.
- concentration of methanol and methacrolein in the recovered methanol varies depending on the reaction mixture to be distilled and the operating conditions of the distillation, but the methanol concentration is usually 30 to 70% by weight.
- the concentration is usually 20 to 70 weight. / 0 .
- the methanol thus recovered can be used as it is as a raw material for producing methyl methacrylate by a direct esterification reaction.
- this as a raw material for the esterification reaction directly in the original reactor or other reactor usually add methanol to methacrylate to adjust to the desired raw material concentration and supply amount. .
- the reaction mixture thus obtained was collected, supplied to a 50-stage distillation column, and low-boiling components such as methyl formate were distilled off from the top of the column.
- the composition of the reaction mixture after distillation is methacryl Methyl 32.1 wt 0/0, methanol 51.1 wt 0/0, methacrolein 8.8 by weight. /.
- the water was 6.4% by weight.
- this liquid was supplied at 394.7 g / h to the 25th stage of an 50-stage Oldash-type distillation column, and methacrolein was supplied to the 24th stage at 105.3 g / h, at a reflux ratio of 2.0. Distillation was performed at an overhead pressure of 8 OkPa'abs.
- methanol from the top of the distillation column - le 53.9 wt 0/0, methacrolein 37.4 wt 0/0, methyl methacrylate 7.4 wt. / Distillate 0 is obtained at 374. lg / h, 7 8. 8 wt% of methyl methacrylate from the bottom, water 1 6.4 wt.
- a liquid, / 0 , substantially free of methacrolein and methanol was obtained at 125.8 g / h.
- the distribution ratio of methyl methacrylate in the distillate to methyl methacrylate in the bottom liquid was 0.28.
- the distillate obtained from the top of the column contained a small amount of methyl methacrylate, but could be directly used as a raw material for the esterification reaction by adding methanol and methacrylate.
- methanol is recovered by distillation from a reaction mixture containing at least methyl methacrylate and methanol obtained by a direct esterification reaction of methacrolein and methanol, and the methanol is directly esterified.
- the process is simplified, the amount of methyl methacrylate contained in the recovered methanol can be reduced, and the target methacrylic acid can be efficiently produced.
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
A process for the preparation of methyl methacrylate, which comprises subjecting methacrolein and methanol to direct esterification to thereby obtain a reaction mixture containing at least methyl methacrylate and methanol, adding additional methacrolein as the entrainer to the reaction mixture, and distilling the resulting mixture to recover the methanol.
Description
明 細 書 メタクリル酸メチルの製造方法 Description Method for producing methyl methacrylate
本発明は、 メタクロレインとメタノールとの直接エステル化反応により得られ る少なくともメタクリル酸メチル及びメタノールを含む反応混合液から蒸留によ りメタノールを回収し、 回収したメタノールを該直接エステル化反応の原料とし て使用することのできるメタクリル酸メチルの製造方法に関する。 The present invention relates to a method for recovering methanol by distillation from a reaction mixture containing at least methyl methacrylate and methanol obtained by direct esterification reaction of methacrolein and methanol, and using the recovered methanol as a raw material for the direct esterification reaction. The present invention relates to a method for producing methyl methacrylate, which can be used as such.
背景技術 Background art
メタクリル酸メチル及びメタノールを含む混合液から蒸留によりメタノールを 回収する方法としては、 特公平 1一 4 7 4 5 4号公報に炭素数 6〜 8の飽和炭化 水素を蒸留塔にフィードしてメタノ一ル等を分離する方法が提案されている。 同様の方法として、 特開昭 5 7— 9 7 4 0号公報には、 メタノール、 水及びメ タクリル酸メチルからなる混合液を蒸留塔にフィードしてメタクリル酸メチルを 蒸留精製するに際し、 炭素数 6〜 7の飽和炭化水素を前記混合液のフィード段よ り実質的に上部に存在させることにより、 塔頂から該飽和炭化水素と実質的に全 量のメタノールを留出させ、 これを相分離槽で分離した後に、 メタノール相を第 2の蒸留塔へ供給しその塔底よりメタノールを回収する方法が提案されている。 また特開昭 5 8— 1 8 0 4 5 7号公報には、 メタノール、 水及びメタクリル酸 メチルからなる混合物に、 メタクリル酸メチル及び水の存在下でメタノールと共 沸混合物を形成する共沸形成剤を添加して共沸蒸留を行うことにより、 共沸形成 剤とメタノールの混合物を塔頂から取り出し、 該混合物が二相分離する場合には、 この二相を分離することにより、 メタノールを分離できることが開示されている。 なお、 このときの好適な共沸形成剤として n—へキサン、 n—オクタン、 シクロ へキサン、 ベンゾール、 トルオール等の炭化水素溶媒のほか、 ジイソプロピルェ 一テル、 テトラヒ ドロフラン、 炭酸ジメチル等の溶媒が挙げられている。 As a method for recovering methanol from a mixed solution containing methyl methacrylate and methanol by distillation, Japanese Patent Publication No. 1144754 discloses a method in which a saturated hydrocarbon having 6 to 8 carbon atoms is fed to a distillation column and methanol is recovered. For example, a method has been proposed for separating the files. As a similar method, Japanese Patent Application Laid-Open No. 57-97440 discloses that a mixed solution of methanol, water and methyl methacrylate is fed to a distillation column to purify methyl methacrylate by distillation. By allowing 6 to 7 saturated hydrocarbons to be present substantially above the mixed liquid feed stage, the saturated hydrocarbons and substantially the entire amount of methanol are distilled off from the top of the column, and this is subjected to phase separation. A method has been proposed in which the methanol phase is supplied to a second distillation column after separation in a tank, and methanol is recovered from the bottom of the column. JP-A-58-180457 discloses an azeotropic formation in which a mixture of methanol, water and methyl methacrylate forms an azeotropic mixture with methanol in the presence of methyl methacrylate and water. The mixture of the azeotropic forming agent and methanol is removed from the top of the column by adding an agent and performing azeotropic distillation, and when the mixture separates into two phases, the methanol is separated by separating the two phases. It is disclosed that it is possible. Suitable azeotropic agents at this time include hydrocarbon solvents such as n-hexane, n-octane, cyclohexane, benzol, and toluene, and solvents such as diisopropyl ether, tetrahydrofuran, and dimethyl carbonate. Are listed.
また、 特開平 7— 6 9 9 4 8号公報には、 反応混合液に炭化水素溶媒及び水を 加えて混和液を得、 該混和液 有機相と含水メタノール相とに二相分離させ、 該 含水メタノール相からメタノールを蒸留分離することによりメタノールを回収す
ることが開示されている。 Japanese Patent Application Laid-Open No. 7-69948 discloses that a mixture is obtained by adding a hydrocarbon solvent and water to a reaction mixture, and the mixture is separated into two phases, an organic phase and a hydrated methanol phase. Recover methanol by distilling off methanol from the aqueous methanol phase Is disclosed.
しかしながら、 これらの方法では、 蒸留の際に共沸剤として多量の炭化水素を 添加して共沸蒸留を行うため、 蒸留に多量のユーティリティ一が必要になる。 さ らに、 回収したメタノ一ルをメタクロレインとの直接エステル化反応に使用して メタクリル酸メチルを製造しょうとすると、 回収したメタノール中に含まれる共 沸剤を蒸留や抽出等により分離する必要があり、 工程が複雑になる。 However, in these methods, a large amount of hydrocarbons are added as an azeotropic agent at the time of distillation to carry out azeotropic distillation, so that a large amount of utility is required for distillation. Furthermore, if methyl methacrylate is to be produced by using the recovered methanol for direct esterification reaction with methacrolein, it is necessary to separate the azeotropic agent contained in the recovered methanol by distillation, extraction, etc. And the process becomes complicated.
メタノールを回収する方法としては、 前記の方法以外に、 共沸剤を用いずに反 応混合液を蒸留する方法もあるが、 この方法では回収したメタノール中に直接ェ ステル化反応の目的生成物であるメタクリル酸メチルが多く含まれるため効率的 でない。 As a method for recovering methanol, there is a method other than the above method, in which the reaction mixture is distilled without using an azeotropic agent.In this method, however, the target product of the esterification reaction is directly contained in the recovered methanol. It is not efficient because it contains a large amount of methyl methacrylate.
発明の開示 Disclosure of the invention
従って、 本発明の目的は、 メタクロレインとメタノールとの直接エステル化反 応により得られる少なくともメタクリル酸メチル及びメタノールを含む反応混合 液から蒸留によりメタノールを回収し、 回収したメタノールを該直接エステル化 反応の原料として使用するメタクリル酸メチルの製造方法において、 工程を単純 化するため、 メタノールを蒸留により回収する際に、 後から分離除去が必要とな るような炭化水素を共沸剤として使用することなく、 回収したメタノ一ル中に含 まれるメタクリル酸メチルの量を少なくすることができる方法を提供することに ある。 Therefore, an object of the present invention is to recover methanol by distillation from a reaction mixture containing at least methyl methacrylate and methanol obtained by direct esterification reaction of methacrolein and methanol, and to recover the recovered methanol by the direct esterification reaction. In the method for producing methyl methacrylate used as a raw material for methane, in order to simplify the process, when recovering methanol by distillation, use a hydrocarbon that needs to be separated and removed later as an azeotropic agent Another object of the present invention is to provide a method capable of reducing the amount of methyl methacrylate contained in the recovered methanol.
本発明者らは鋭意検討を行った結果、 蒸留によりメタノールを回収する際に共 沸剤としてメタクロレインを別途添加することにより、 上記の問題が解決できる ことを見出し本発明を完成するに至った。 As a result of intensive studies, the present inventors have found that the above problem can be solved by separately adding methacrolein as an azeotropic agent when recovering methanol by distillation, and have completed the present invention. .
すなわち、 本発明は、 メタクロレインとメタノールとの直接エステル化反応に より少なくともメタクリル酸メチル及びメタノールを含む反応混合液を得、 該反 応混合液に共沸剤としてメタクロレインを別途添加し、 該反応混合液から蒸留に よりメタノ一ルを回収することを含むメタクリル酸メチルの製造方法にある。 本発明において、 回収したメタノールは直接エステル化反応によるメタクリル 酸メチルを製造するための原料として使用することができる。 That is, the present invention provides a reaction mixture containing at least methyl methacrylate and methanol by a direct esterification reaction of methacrolein and methanol, and separately adding methacrolein as an azeotropic agent to the reaction mixture. A method for producing methyl methacrylate, which comprises recovering methanol from a reaction mixture by distillation. In the present invention, the recovered methanol can be used as a raw material for producing methyl methacrylate by a direct esterification reaction.
発明を実施するための最良の形態
本発明において、 メタクロレインとメタノールとの直接エステル化反応（以下 単に直接エステル化反応という）によりメタクリル酸メチルを製造する方法は特 に限定されず、 気相及び液相反応の何れでもよい。 また、 反応形式も特に限定さ れず、 連続式及び回分式等のいずれの方式でもよい。 具体的には、 パラジウム系 触媒を用いて液相で連続的に反応を行う方法等が挙げられる。 BEST MODE FOR CARRYING OUT THE INVENTION In the present invention, a method for producing methyl methacrylate by a direct esterification reaction of methacrolein with methanol (hereinafter, simply referred to as a direct esterification reaction) is not particularly limited, and may be a gas phase or a liquid phase reaction. Further, the reaction system is not particularly limited, and may be any system such as a continuous system and a batch system. Specifically, a method of continuously performing a reaction in a liquid phase using a palladium-based catalyst is exemplified.
通常、 直接エステル化反応により得られる反応混合液には、 未反応原料及び生 成物であるメタクリル酸メチルが含まれているが、 本発明の対象となる反応混合 液は、 少なくとも、 未反応原料であるメタノ一ル及び生成物であるメタクリル酸 メチルが含まれたものである。 Normally, the reaction mixture obtained by the direct esterification reaction contains unreacted raw materials and the product methyl methacrylate, but the reaction mixture which is the object of the present invention comprises at least unreacted raw materials. And methyl methacrylate as a product.
反応混合液に含まれるメタノ一ルゃメタクリル酸メチルの濃度は反応条件等に より様々であるが、 例えばパラジウム系触媒を用いて液相で反応を行った場合の 反応混合液に含まれるメタノールの濃度は通常 2 5〜 7 0重量。 /0、 メタクリル酸 メチルの濃度は通常 2 0〜6 0重量％である。 通常反応混合液には、 この他に未 反応原料であるメタクロレイン、 副生成物であるギ酸メチル及び水等が含まれる。 反応混合液からギ酸メチル等の低沸点副生物を除去する必要がある場合には、 メタノールを回収するための蒸留の前に、 例えば、 反応混合液を予め蒸留塔へ供 給し塔頂より一部のメタク口レインゃメタノールとともに低沸点副生物を留去す る等の操作を行うとよレ、。 The concentration of methanol-methyl methacrylate contained in the reaction mixture varies depending on the reaction conditions and the like.For example, when the reaction is performed in the liquid phase using a palladium catalyst, the concentration of methanol contained in the reaction mixture is The concentration is usually 25 to 70 weight. / 0 , the concentration of methyl methacrylate is usually 20 to 60% by weight. In general, the reaction mixture further contains unreacted raw materials such as methacrolein, by-products such as methyl formate and water. When it is necessary to remove low-boiling by-products such as methyl formate from the reaction mixture, before the distillation for recovering methanol, for example, the reaction mixture is supplied to a distillation column in advance, and one minute is supplied from the top of the column. Some operations such as distilling off low-boiling by-products together with methanol in part of the methacrine rain.
本発明において、 反応混合液から蒸留によりメタノールを回収する際には、 該 反応混合液に共沸剤としてメタクロレインを別途添加する。 メタクロレインを添 加する方法は特に制限されないが、 例えば、 反応混合液及びメタクロレインを蒸 留塔の適当な位置にそれぞれ供給する方法、 反応混合液にメタク口レインを添加 した後に蒸留塔に供給する方法等が挙げられる。 この蒸留により、 メタノールは 共沸するメタクロレインとともに塔頂から取り出される。 In the present invention, when methanol is recovered from the reaction mixture by distillation, methacrolein is separately added as an azeotropic agent to the reaction mixture. The method of adding methacrolein is not particularly limited.For example, a method of supplying the reaction mixture and methacrolein to appropriate positions in the distillation column, and a method of adding methacrolein to the reaction mixture and then supplying the mixture to the distillation column And the like. By this distillation, methanol is removed from the top of the column together with azeotropic methacrolein.
このときのメタクロレインの添加量は、 反応混合液中のメタノール 1 0 0重量 部に対して 2 0〜2 0 0重量部が好ましく、 特に 4 0〜8 0重量部が好ましい。 メタクロレインの添加量が 2 0重量部未満の場合、 メタノ一ルの回収の際に多量 のメタクリル酸メチルが留出してメタノールの回収が困難になる場合があり、 2 0 0重量部を超えると、 過剰のメタクロレインが反応器へリサイクルされ、 原料
のメタノールとメタクロレインの比率が適切な範囲に制御できなくなる等の反応 への悪影響が生じたり、 メタクロレインが重合する場合がある。 At this time, the amount of methacrolein to be added is preferably 20 to 200 parts by weight, particularly preferably 40 to 80 parts by weight, based on 100 parts by weight of methanol in the reaction mixture. If the amount of methacrolein is less than 20 parts by weight, a large amount of methyl methacrylate may be distilled out during the recovery of methanol, making it difficult to recover methanol. The excess methacrolein is recycled to the reactor, In some cases, the ratio of methanol to methacrolein cannot be controlled within an appropriate range, adverse effects on the reaction may occur, and methacrolein may be polymerized.
本発明において、 メタノールの回収に用いられる蒸留塔の形式は特に限定され ず、 例えば棚段形式、 充填塔形式等の公知の形式のものが利用できる。 塔内で二 液相を形成する場合はデカンターを設けて水を分離して取り出してもよい。 また 蒸留条件は特に制限されないが、 蒸留圧力は常圧又は減圧が好ましく、 塔底温度 は重合を防止するために 1 2 0 °C以下が好ましい。 In the present invention, the type of distillation column used for recovering methanol is not particularly limited, and for example, a known type such as a tray type or a packed column type can be used. When two liquid phases are formed in the column, a decanter may be provided to separate and take out water. The distillation conditions are not particularly limited, but the distillation pressure is preferably normal pressure or reduced pressure, and the bottom temperature is preferably 120 ° C. or lower to prevent polymerization.
本発明においては、 蒸留により回収されたメタノール中にはメタクロレインが 含まれる。 この回収されたメタノール中のメタノール及びメタクロレインの濃度 は蒸留対象である反応混合液や蒸留の操作条件等により様々であるが、 メタノー ル濃度は通常 3 0〜 7 0重量％であり、 メタクロレイン濃度は通常 2 0〜 7 0重 量。 /0である。 In the present invention, methacrolein is contained in methanol recovered by distillation. The concentration of methanol and methacrolein in the recovered methanol varies depending on the reaction mixture to be distilled and the operating conditions of the distillation, but the methanol concentration is usually 30 to 70% by weight. The concentration is usually 20 to 70 weight. / 0 .
このように回収されたメタノールは、 そのまま直接エステル化反応によるメタ クリル酸メチルを製造するための原料として利用できる。 これを元の反応器又は その他の反応器において直接エステル化反応の原料として使用する際には、 通常 メタノ一ルゃメタク口レインを適宜添加して、 所望の原料濃度や供給量に調節す る。 The methanol thus recovered can be used as it is as a raw material for producing methyl methacrylate by a direct esterification reaction. When using this as a raw material for the esterification reaction directly in the original reactor or other reactor, usually add methanol to methacrylate to adjust to the desired raw material concentration and supply amount. .
以下に本発明を実施例及び比較例により具体的に説明する。 なお、 反応混合液 等の重量組成の分析は、 ガスクロマトグラフィ一により行った。 Hereinafter, the present invention will be specifically described with reference to Examples and Comparative Examples. The weight composition of the reaction mixture and the like was analyzed by gas chromatography.
実施例 1 Example 1
4 Lの還流器、 攪拌機付きの反応器に、 触媒 （5重量％パラジウム一 1重量％ 鉛一 1重量0 /0鉄を含有した炭酸カルシウム触媒） 3 5 0 g、 メタクロレイン 7 0 0 g、 メタノール 1 2 8 0 gの反応液を投入し、 更に空気を毎分 4 . 7 7 Nリット ル、 窒素を毎分 5 . O Nリッ トルの速度で吹き込みながら、 圧力 4 0 0 kPa' abs、 浴温 8 0 °Cで 4時間反応させてメタクリル酸メチルを合成した。 反応生成物を捕 集し分析した結果、 メタクロレインの転化率 7 5 . 1 %、 メタクリル酸メチルの 選択率 8 5 . 2。/。であった。 4 L reflux condenser, and the reactor equipped with a stirrer, a catalyst (5 wt% palladium one 1 wt% lead one 1 wt 0/0 Iron calcium carbonate catalyst containing) 3 5 0 g, methacrolein 7 0 0 g, A reaction solution of 1,280 g of methanol was charged, and air was blown at a rate of 4.77 N liters per minute and nitrogen at a rate of 5.ON liters per minute while applying a pressure of 400 kPa'abs. The reaction was carried out at a temperature of 80 ° C. for 4 hours to synthesize methyl methacrylate. As a result of collecting and analyzing the reaction products, the conversion of methacrolein was 75.1% and the selectivity of methyl methacrylate was 85.2. /. Met.
このようにして得られた反応混合液を集め、 5 0段の蒸留塔に供給し、 塔頂よ りギ酸メチル等の低沸分を留去した。 蒸留後の反応混合液の組成は、 メタクリル
酸メチル 32. 1重量0 /0、 メタノール 51. 1重量0 /0、 メタクロレイン 8. 8重 量。/。、 水 6. 4重量％であった。 The reaction mixture thus obtained was collected, supplied to a 50-stage distillation column, and low-boiling components such as methyl formate were distilled off from the top of the column. The composition of the reaction mixture after distillation is methacryl Methyl 32.1 wt 0/0, methanol 51.1 wt 0/0, methacrolein 8.8 by weight. /. The water was 6.4% by weight.
次に、 この液を 394. 7g/hで 50段のオールダショゥ式の蒸留塔の 25段 目に供給し、 メタクロレインを 105. 3g/hで 24段目に供給し、 還流比 2. 0で塔頂圧力 8 OkPa'absで蒸留を行った。 その結果、 蒸留塔の塔頂よりメタノ —ル 53. 9重量0 /0、 メタクロレイン 37. 4重量0 /0、 メタクリル酸メチル 7. 4重量。 /0の留出液が 374. lg/hで得られ、 塔底からはメタクリル酸メチル 7 8. 8重量％、 水 1 6. 4重量。 /0という、 メタクロレイン及びメタノールを実質 的に含まない液が 1 25. 8g/hで得られた。 塔底液中のメタクリル酸メチルに 対する留出液中のメタクリル酸メチルの分配比は 0. 28であった。 塔頂から得 られる留出液は、 メタクリル酸メチルを少量含むものの、 メタノール及びメタク 口レインを追加することにより直接エステル化反応の原料として問題なく使用す ることができた。 Next, this liquid was supplied at 394.7 g / h to the 25th stage of an 50-stage Oldash-type distillation column, and methacrolein was supplied to the 24th stage at 105.3 g / h, at a reflux ratio of 2.0. Distillation was performed at an overhead pressure of 8 OkPa'abs. As a result, methanol from the top of the distillation column - le 53.9 wt 0/0, methacrolein 37.4 wt 0/0, methyl methacrylate 7.4 wt. / Distillate 0 is obtained at 374. lg / h, 7 8. 8 wt% of methyl methacrylate from the bottom, water 1 6.4 wt. A liquid, / 0 , substantially free of methacrolein and methanol was obtained at 125.8 g / h. The distribution ratio of methyl methacrylate in the distillate to methyl methacrylate in the bottom liquid was 0.28. The distillate obtained from the top of the column contained a small amount of methyl methacrylate, but could be directly used as a raw material for the esterification reaction by adding methanol and methacrylate.
比較例 1 Comparative Example 1
実施例 1において、 メタクロレインを蒸留塔に供給しなかったこと以外は、 実 施例 1と同様にしてメタノールを回収するための蒸留を行った。 その結果、 蒸留 塔の塔頂よりメタノール 72. 0重量％、 メタクロレイン 1 2. 3重量％、 メタ クリル酸メチル 14. 7重量。 /0の液が 280. Og/hで得られ、 塔底からはメタ クリル酸メチル 74. 7重量。 /0、 水 20. 1重量。 /0という、 メタクロレイン及び メタノールを実質的に含まない液が 1 14. 7g/hで得られた。 しかしながら、 塔底液中のメタクリル酸メチルに対する留出液中のメタクリル酸メチルの分配比 が 0. 48と実施例 1に比べて多くなつた。 Distillation for recovering methanol was performed in the same manner as in Example 1 except that methacrolein was not supplied to the distillation column in Example 1. As a result, 72.0% by weight of methanol, 12.3% by weight of methacrolein, and 14.7% by weight of methyl methacrylate from the top of the distillation column. / 0 liquid was obtained at 280. Og / h and methyl methacrylate 74.7 weight from the bottom of the column. / 0 , water 20.1 weight. / 0 of the liquid which does not contain the methacrolein and methanol substantially is obtained by 1 14. 7 g / h. However, the distribution ratio of methyl methacrylate in the distillate to methyl methacrylate in the bottom liquid was 0.48, which was larger than that in Example 1.
産業上の利用可能性 Industrial applicability
本発明の方法により、 メタクロレインとメタノールとの直接エステル化反応に よって得られる、 少なくとも、 メタクリル酸メチル及びメタノールを含む反応混 合液から、 メタノールを蒸留により回収して、 このメタノールを直接エステル化 反応の原料として使用すれば、 工程が単純化され、 回収したメタノール中に含ま れるメタクリル酸メチルを少なくすることができ、 目的物であるメタクリル酸を 効率良く製造することができる。
According to the method of the present invention, methanol is recovered by distillation from a reaction mixture containing at least methyl methacrylate and methanol obtained by a direct esterification reaction of methacrolein and methanol, and the methanol is directly esterified. When used as a reaction raw material, the process is simplified, the amount of methyl methacrylate contained in the recovered methanol can be reduced, and the target methacrylic acid can be efficiently produced.
Claims
1. メタクロレインとメタノールとを直接エステル化反応に付し、 少なくとも メタクリル酸メチル及びメタノールを含む反応混合液を得、 該反応混合液に共沸 剤としてメタクロレインを別途添カ卩し、 該反応混合液から蒸留によりメタノール を回収することを含む、 メタクリル酸メチルの製造方法。 1. Directly esterify methacrolein and methanol to obtain a reaction mixture containing at least methyl methacrylate and methanol, and separately add methacrolein as an azeotropic agent to the reaction mixture, A method for producing methyl methacrylate, comprising recovering methanol from a mixed solution by distillation.
2. 回収したメタノールを前記直接エステル化反応の原料として使用する請求 の範囲 1記載の製造方法。
2. The production method according to claim 1, wherein the recovered methanol is used as a raw material for the direct esterification reaction.
Priority Applications (4)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02731998A JP3238894B2 (en) | 1998-02-09 | 1998-02-09 | Method for producing methyl methacrylate |
| CNB998168394A CN1155556C (en) | 1998-02-09 | 1999-08-06 | Process for the preparation of methyl methacrylate |
| US10/048,465 US6680405B1 (en) | 1998-02-09 | 1999-08-06 | Process for the preparation of methyl methacrylate |
| PCT/JP1999/004268 WO2001010811A1 (en) | 1998-02-09 | 1999-08-06 | Process for the preparation of methyl methacrylate |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP02731998A JP3238894B2 (en) | 1998-02-09 | 1998-02-09 | Method for producing methyl methacrylate |
| PCT/JP1999/004268 WO2001010811A1 (en) | 1998-02-09 | 1999-08-06 | Process for the preparation of methyl methacrylate |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| WO2001010811A1 true WO2001010811A1 (en) | 2001-02-15 |
Family
ID=26365234
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| PCT/JP1999/004268 WO2001010811A1 (en) | 1998-02-09 | 1999-08-06 | Process for the preparation of methyl methacrylate |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JP3238894B2 (en) |
| CN (1) | CN1155556C (en) |
| WO (1) | WO2001010811A1 (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2017533214A (en) * | 2014-10-31 | 2017-11-09 | ダウ グローバル テクノロジーズ エルエルシー | Method for removing water in situ from an oxidative esterification reaction using a linked reactor-distillation system |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6680405B1 (en) | 1998-02-09 | 2004-01-20 | Mitsubishi Rayon Co., Ltd. | Process for the preparation of methyl methacrylate |
| JP3238894B2 (en) * | 1998-02-09 | 2001-12-17 | 三菱レイヨン株式会社 | Method for producing methyl methacrylate |
| KR20200105854A (en) * | 2018-01-10 | 2020-09-09 | 다우 글로벌 테크놀로지스 엘엘씨 | Heterogeneous catalyst for the production of methyl methacrylate by oxidative esterification |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS579739A (en) * | 1980-06-20 | 1982-01-19 | Asahi Chem Ind Co Ltd | Purification of methyl methacrylate |
| JPS58180457A (en) * | 1982-03-31 | 1983-10-21 | バスフ アクチェン ゲゼルシャフト | Separation of methanol from mixture of methylmethacrylate and methanol water |
| JPH08268938A (en) * | 1995-03-29 | 1996-10-15 | Osaka Organic Chem Ind Ltd | Separation of methyl acrylate or methyl methacrylate and methanol |
| JPH10306052A (en) * | 1997-05-08 | 1998-11-17 | Nippon Shokubai Co Ltd | Recovery of acrylic acid |
| JPH11228498A (en) * | 1998-02-09 | 1999-08-24 | Mitsubishi Rayon Co Ltd | Production of methyl methacrylate |
-
1998
- 1998-02-09 JP JP02731998A patent/JP3238894B2/en not_active Expired - Lifetime
-
1999
- 1999-08-06 WO PCT/JP1999/004268 patent/WO2001010811A1/en active Application Filing
- 1999-08-06 CN CNB998168394A patent/CN1155556C/en not_active Expired - Lifetime
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPS579739A (en) * | 1980-06-20 | 1982-01-19 | Asahi Chem Ind Co Ltd | Purification of methyl methacrylate |
| JPS58180457A (en) * | 1982-03-31 | 1983-10-21 | バスフ アクチェン ゲゼルシャフト | Separation of methanol from mixture of methylmethacrylate and methanol water |
| JPH08268938A (en) * | 1995-03-29 | 1996-10-15 | Osaka Organic Chem Ind Ltd | Separation of methyl acrylate or methyl methacrylate and methanol |
| JPH10306052A (en) * | 1997-05-08 | 1998-11-17 | Nippon Shokubai Co Ltd | Recovery of acrylic acid |
| JPH11228498A (en) * | 1998-02-09 | 1999-08-24 | Mitsubishi Rayon Co Ltd | Production of methyl methacrylate |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2017533214A (en) * | 2014-10-31 | 2017-11-09 | ダウ グローバル テクノロジーズ エルエルシー | Method for removing water in situ from an oxidative esterification reaction using a linked reactor-distillation system |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1155556C (en) | 2004-06-30 |
| JPH11228498A (en) | 1999-08-24 |
| JP3238894B2 (en) | 2001-12-17 |
| CN1361761A (en) | 2002-07-31 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| KR100192733B1 (en) | Removal of carbonyl impurities from a carbonylation process stream | |
| KR101233605B1 (en) | Removal of permanganate reducing compounds from methanol carbonylation process stream | |
| KR100760100B1 (en) | Process for the simultaneous coproduction and purification of ethyl acetate and isopropyl acetate | |
| KR100408144B1 (en) | Recovery of acetic acid from diluent aqueous streams formed during the carbonylation process | |
| KR20060129427A (en) | Removal of permanganate reducing compounds from methanol carbonylation process stream | |
| KR100414249B1 (en) | Process for purifying acetic acid | |
| USRE31010E (en) | Preparation of carboxylic acid esters with BF3 complex catalyst | |
| EP0031205A2 (en) | Carbonylation of ethylene or propylene | |
| KR100407510B1 (en) | Dewatering process | |
| EP0044409B1 (en) | Process for purifying methyl methacrylate | |
| JP2019163294A (en) | Manufacturing method of light (meth)acrylic acid ester | |
| RU2203264C2 (en) | Method of synthesis of acetic acid | |
| JP2003026633A (en) | Method for producing methacrylic ester | |
| KR19980071856A (en) | Recovery method of acrylic acid | |
| WO2001010811A1 (en) | Process for the preparation of methyl methacrylate | |
| US4262138A (en) | Preparation of carboxylic acid esters with BF3 complex catalyst | |
| EP0628546A2 (en) | Integrated process for the production of ditertiary butyl peroxide | |
| US6680405B1 (en) | Process for the preparation of methyl methacrylate | |
| EP0455906B1 (en) | Recovery of acrylic acid and/or ethyl acrylate from black acid | |
| JPH0832667B2 (en) | Purification method of dimethyl carbonate | |
| JPH0142252B2 (en) | ||
| JPH09278703A (en) | Purification of acetone | |
| JP2000001458A (en) | Production of methyl methacrylate | |
| JPH0769948A (en) | Recovery of methanol | |
| JPH072735A (en) | Production of isopropyl acetate |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| AK | Designated states |
Kind code of ref document: A1 Designated state(s): CN US |
|
| DFPE | Request for preliminary examination filed prior to expiration of 19th month from priority date (pct application filed before 20040101) | ||
| WWE | Wipo information: entry into national phase |
Ref document number: 998168394 Country of ref document: CN |
|
| WWE | Wipo information: entry into national phase |
Ref document number: 10048465 Country of ref document: US |