JP2009143866A - Method for producing ditrimethylolpropane - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop a method for producing ditrimethylolpropane (di-TMP) without using conventional n-butyraldehyde, since the method for producing the di-TMP collects the di-TMP as a byproduct of the production of TMP, the content of the di-TMP is low, and therefore, in order to increase the di-TMP production amount, it is necessary to increase the content of the same. <P>SOLUTION: This method for producing the di-TMP is provided by reacting 2-ethyl-2-propenal with formaldehyde and a base. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a method for efficiently producing ditrimethylolpropane (hereinafter referred to as di-TMP).

  Under a base, trimethylolpropane (hereinafter referred to as TMP) is obtained by aldol condensation between normal butyraldehyde (hereinafter referred to as NBD) and formaldehyde (base acts as a condensation catalyst) and cross Canitz allo reaction (base is consumed as a reactant). When di-TMP is produced industrially, di-TMP having a higher boiling point is produced as a by-product, and di-TMP is obtained by recovering from the high-boiling mixture (residue in the still). reference). That is, a TMP extract (crude TMP) substantially free of sodium formate can be obtained by extracting the reaction product solution of NBD and formaldehyde using a solvent after or without concentration. When this crude TMP is purified by distillation under high vacuum, 1 to 20% of TMP and 20 to 50% of di-TMP are contained in the residue of the distillation kettle. As a method for recovering di-TMP from the residue in the kettle, a method of crystallization with ethyl acetate (see Patent Document 2), a method of crystallization with an aqueous solvent in the presence of sodium formate (see Patent Document 3), 1 , 4-dioxane solvent (see Patent Document 4), a method of strictly defining the conditions and crystallizing with an acetone solvent (see Patent Document 5), and the like have been proposed. In addition, as a method for increasing the amount of di-TMP by-products in producing TMP, a method of setting reaction conditions to a specific condition (see Patent Documents 6 and 7) has been proposed. A method of adding an organic solvent immiscible with water to the reaction system (see Patent Document 8) has also been proposed.

On the other hand, as a method for obtaining di-TMP itself by synthesis, a method for obtaining di-TMP by producing an ether bond by dehydration condensation of two molecules of TMP, or a method in which the method is partially improved (see Patent Document 9). It has been known. Furthermore, a method of synthesizing di-TMP by reacting 2-ethyl-2-propenal (hereinafter referred to as ECR) and TMP is also known (see Patent Document 10).
US Pat. No. 3,097,245 JP 47-30611 A JP-A 49-13311 JP 2002-47231 A Japanese Patent Laid-Open No. 2005-23067 Japanese Patent Laid-Open No. 57-139028 JP 57-142929 A JP-A-8-157401 JP-T 6-501470 JP-A-9-268150

The above-described method for obtaining di-TMP as a by-product in the production of TMP has the following problems.
The production method generally used at present is a method for recovering TMP, which is the main object, from the residue in the distillation still. In this method, a TMP reaction mixture such as formaldehyde or NBD which is a raw material for TMP, a modified product generated during TMP distillation recovery, or a by-product other than di-TMP such as acetal of TMP and formaldehyde is used. It is difficult to recover di-TMP in an industrially satisfactory yield since only the content of di-TMP is required to be separated and recovered. Therefore, since di-TMP is a by-product of TMP production, the production amount is inevitably limited by the production amount of TMP, and there is a problem that it cannot cope with the increase in demand for di-TMP.

On the other hand, the method of synthesizing di-TMP by producing an ether bond by dehydration condensation of two molecules of TMP can solve the above-described problem of increase in the supply and demand of di-TMP.
However, in the case of TMP having a structure having three alcoholic hydroxyl groups that can participate in the reaction in one molecule, since it is a reaction between TMP molecules, the by-product of three or more molecules of the ether condensate that is inevitably generated can be avoided. Absent. In order to suppress this, the reaction rate of the dehydration condensation reaction of TMP must be set low, and accordingly, the recovery of unreacted TMP becomes a large economic burden and is industrially disadvantageous.

In order to improve this point, Patent Document 9 describes a method using TMP obtained by reacting a part of three alcoholic hydroxyl groups in advance as an ester of a lower fatty acid as a raw material. However, even in this method, it is not possible to selectively react only two alcoholic hydroxyl groups in one molecule of TMP as an ester of a lower fatty acid. It is hard to say that it has been resolved. In this method, the step of regenerating di-TMP by hydrolysis from di-TMP having esterified alcoholic hydroxyl groups produced from TMP esterified with one or two alcoholic hydroxyl groups. Newly required, the economic burden increases and it is industrially disadvantageous.
Further, Patent Document 10 describes a method for obtaining di-TMP from excess TMP and ECR. In this method, even when TMP is used in a large excess with respect to ECR, the yield of di-TMP based on ECR is obtained. The rate is less than 70%, and moreover, the TMP used excessively needs to be recovered, which is economically disadvantageous. An object of the present invention is to provide a method for producing di-TMP efficiently and industrially advantageously.

As a result of intensive studies on a method for producing di-TMP having the above-mentioned problems, the present inventors have found that di-TMP can be efficiently produced, and have completed the present invention. That is, this invention relates to the manufacturing method of following (A)-(H) description.
(A)
A process for producing di-TMP in which ECR is reacted with formaldehyde and a base.
(B)
A method for producing di-TMP according to (A), in which at least one component of ECR, formaldehyde, and a base is partially charged before the start of the reaction, and the rest is added and reacted.
(C)
The method for producing di-TMP according to claim 1, wherein at least one component of ECR and formaldehyde is partially charged before the start of the reaction, and the rest and a base are added after the reaction.
(D)
The method for producing di-TMP according to any one of (A) to (C), wherein a part of the amount of ECR is 10 to 100% of the total amount of ECR.
(E)
The method for producing di-TMP according to any one of (A) to (D), wherein a part of formaldehyde is 10 to 100% of the total amount of formaldehyde.
(F)
The manufacturing method of di-TMP of any one of (A)-(E) whose total amount of formaldehyde is 2.0-10.0 mol with respect to 1.0 mol total amount of ECR.
(G)
The method for producing di-TMP according to any one of (A) to (F), wherein an equivalent amount of a part of the base is 10 to 90% with respect to a total equivalent amount of the base.
(H)
The method for producing di-TMP according to any one of (A) to (G), wherein the total equivalent of the base is 0.5 to 2.5 equivalents relative to a total of 1.0 mol of ECR.
(I)
The method for producing di-TMP according to any one of (A) to (H), in which an unreacted product of ECR and formaldehyde is collected and reused.

According to the present invention, at least one component of ECR, formaldehyde, and base is added, and the remainder is added and reacted to suppress the production of TMP as a main product, and to produce di-TMP as a target product. The ratio can be increased, whereby di-TMP can be produced efficiently. Moreover, in the method of the present invention, unreacted raw materials (ECR, formaldehyde) having a boiling point lower than that of di-TMP can be recovered by distillation and recycled, so that the present invention is an industrially extremely advantageous method. .
Hereinafter, the present invention will be described in more detail.

  As the ECR used in the present invention, a commercially available product may be used as it is, or a product obtained by further purifying the commercially available product by distillation or the like. Of course, these can be synthesized and used by a generally known method. For ECR, it is also possible to use an ECR recovered product by-produced in TMP production, for example, recovered ECR containing organic components such as water and methanol.

  The formaldehyde used in the present invention may be an aqueous formaldehyde solution or solid paraformaldehyde. The aqueous formaldehyde solution usually contains several percent of methanol as a stabilizer, but can be used in the reaction after separation by distillation or the like if necessary.

  The total amount of formaldehyde is preferably 2.0 to 10.0 mol with respect to 1.0 mol of the total amount of ECR. When the molar ratio is smaller than this range, the amount of di-TMP produced decreases and the by-products also increase. If the molar ratio is larger than this range, a large amount of energy is required to recover excess formaldehyde, which is industrially disadvantageous.

  As the base used in the present invention, both inorganic bases and organic bases can be used. Examples of the inorganic base include sodium hydroxide, potassium hydroxide, calcium hydroxide, lithium hydroxide and carbonate as sodium hydroxide, potassium carbonate, calcium carbonate, carbonate as alkali metal or alkaline earth metal hydroxide. Although lithium etc. are mentioned, The thing which has carbonate and / or hydrogen carbonate of an alkali metal or alkaline-earth metal as a main component, Especially preferably, what has an alkali metal carbonate as a main component is used. For industrial implementation, sodium inorganic base is generally used.

  As the organic base, aliphatic amine compounds, particularly tertiary amines such as trimethylamine, triethylamine, diethylmethylamine, dimethylethylamine, triisopropylamine, and tributylamine are used.

  Inorganic bases and organic bases can be used not only independently, but also in combination, for example, triethylamine as a partially added base and sodium hydroxide as a post-added base can be used in combination. However, in the case where the main component is carbonate, carbonate is consumed in the reaction, and the hydrogen carbonate generated in the reaction is converted to carbonate by heating or the like and consumed in the reaction. This base may be a carbonate or a mixture with bicarbonate generally used as an industrial chemical. Further, a carbonate produced by oxidizing or hydrolyzing a formate salt as a raw material or a mixture with a bicarbonate may be used.

  The total equivalent of the base used is preferably 0.5 to 2.5 equivalents, more preferably 1.0 to 1.5 equivalents, relative to 1.0 mol of the total amount of ECR. For example, the equivalent of sodium carbonate, which is 2 equivalents of the base, is preferably 0.5 to 2.5 equivalents (0.25 to 1.25 mol) with respect to 1.0 mol of the total amount of ECR. If it is less than this range, not only a large amount of unreacted raw material remains, but also a side reaction from the unreacted raw material occurs. On the other hand, when the amount is larger than this range, a large amount of acid is required when neutralizing the excess base, which is not preferable.

  The reaction method of the present invention is a method of reacting ECR, which does not use NBD, formaldehyde, and a base. More preferably, a part of ECR, at least one component of formaldehyde and a base is charged before starting the reaction, and the rest is left behind. It is a method of adding and reacting, more preferably, a method in which at least one component of ECR and formaldehyde is partially charged before starting the reaction, and then the rest and a base are added.

  10-100 mass% is preferable with respect to the total amount of ECR used for the whole reaction, and, more preferably, 10-70 mass% of ECR is partially charged. Outside this range, many by-products are obtained, which is not preferable.

  The partial charge of formaldehyde is preferably 10 to 100%, more preferably 30 to 90%, based on the total amount of formaldehyde used in the entire reaction. Outside this range, many by-products are obtained, which is not preferable.

  The base charge is preferably 10 to 90%, more preferably 10 to 70%, based on the total equivalent of base used in the entire reaction. Outside this range, many by-products are obtained, which is not preferable.

  The dropping time of at least one component of formaldehyde, ECR and base to be added later is preferably 1 to 600 minutes, more preferably 20 to 240 minutes. If it is shorter than this, many by-products are obtained, and if it is longer than this, the production efficiency is poor and it is industrially disadvantageous.

  The reaction temperature of ECR, formaldehyde and base is preferably 0 to 120 ° C, more preferably 20 to 110 ° C. After all the raw materials have been added, the reaction can be further advanced by heating at 0 to 120 ° C. for 1 to 300 minutes. In this case, in order to keep the inside of the system at a predetermined reaction temperature, pressurization may be performed with an inert gas such as nitrogen gas.

  After completion of the reaction, the unreacted raw material ECR is recovered and reused. This separation and recovery can be easily performed by distillation under reduced pressure, normal pressure or pressurized conditions. The distillate obtained here contains components such as water and methanol in addition to ECR, but this distillate can be used in the next synthesis reaction as it is or after purification by distillation or the like. . Unreacted formaldehyde may be any of reduced pressure, normal pressure, and pressurized after recovering the raw material ECR, but recovered by distillation and reused.

  The target di-TMP can be isolated and purified from the obtained reaction solution by an operation generally performed in TMP purification, and the method is not particularly limited. For example, unreacted ECR is recovered by distillation. Then, after neutralizing the reaction solution, unreacted formaldehyde as a raw material is recovered, extracted, and then recovered and purified by distillation or crystallization.

EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, of course, this invention is not limited by these Examples. The raw material used in this example was a commercially available reagent. Formaldehyde aqueous solution is a product manufactured by Mitsubishi Gas Chemical Co., Ltd., sodium carbonate is a special product manufactured by Wako Pure Chemical Industries, Ltd., NBD is a special product manufactured by Aldrich, and a purity of 78% ECR is an ECR recovered product produced as a by-product of TMP production. Used a recovered product of 13% water, 6% methanol, 3% organic components other than methanol, and 78% ECR. The analysis was performed using gas chromatography (GC) by diluting the sample and the internal standard sample with an acetone solvent.
[Gas chromatography analysis conditions].
Equipment: HP-5890 (manufactured by Agilent Technologies)
Column used: DB-1 (manufactured by Agilent Technologies)
Analysis conditions: Injection Temp 250 ° C.
Detector Temp 250 ° C
Column temperature: 60 ° C., hold for 6 minutes → heat up to 250 ° C. at 7 ° C./minute→250° C., hold for 20 minutes Detector: Hydrogen flame ionization detector (FID)

Reference example (conventional production method from NBD and formaldehyde)
A 2000 ml four-necked flask equipped with a reflux condenser, a thermometer, and two dropping funnels was charged with a total of 431 g of a 32% by weight aqueous formaldehyde solution (4.6 mol as formaldehyde) and heated to 73 ° C. Thereafter, 104 g (1.45 mol) of NBD having a purity of 99.9% and a total amount of 383 g (0.77 mol as sodium carbonate) of a 21 mass% sodium carbonate aqueous solution were added from the dropping funnel while gradually heating, respectively, for 184 minutes. Added in 25 minutes. After the addition, it was heated and held at 89 ° C. for 180 minutes. By GC analysis of the obtained reaction mixture, TMP was calculated to be 132.7 g and di-TMP was calculated to be 5.7 g. The yield based on NBD standards of the raw materials was 67.7% for TMP and 3.1% for di-TMP, respectively.

Example 1 (ECR 12% charge, 88% post-addition, synthesis example 1 from ECR and formaldehyde)
A 1000 ml four-necked flask equipped with a reflux condenser, a thermometer, and two dropping funnels was charged with 300 g of a 27% by mass aqueous formaldehyde solution (2.7 mol as formaldehyde, 100% of the total charge), and a purity of 78% ECR15. 9 g (0.15 mol as ECR, 12% of the total charged amount) was charged and heated to 74 ° C. Thereafter, while gradually heating, ECR 110 g with a purity of 78% (1.3 mol as ECR, 88% of the total charge) and 263 g of a 21% by mass aqueous sodium carbonate solution (0.53 mol as sodium carbonate, 100% of the total charge) %) Was added with two dropping funnels in 30 minutes and 25 minutes, respectively. After heating and maintaining at 87 ° C. for 60 minutes, unreacted ECR was recovered by distillation at 103 ° C. and 70 minutes. The recovered distillate was 111 g, of which 25 g of ECR was contained. By GC analysis of the obtained reaction mixture, 70.0 g of TMP and 16 g of di-TMP were calculated. The yield based on ECR standards of the raw materials was 59.9% for TMP and 14.7% for di-TMP, respectively.

Example 2 (ECR 15% charge, 85% post-addition, synthesis example 2 from ECR and formaldehyde)
A 1000 ml four-necked flask equipped with a reflux condenser, a thermometer, and two dropping funnels was charged with 300 g of a 27% by mass aqueous formaldehyde solution (2.7 mol as formaldehyde, 100% of the total charge), and a purity of 78% ECR15. 9 g (0.15 mol as ECR, 15% of the total charged amount) was charged and heated to 74 ° C. Thereafter, while gradually heating, purity 78% ECR 88 g (0.8 mol as ECR, 85% of the total charged amount) and 263 g of 21 mass% sodium carbonate aqueous solution (0.53 mol as sodium carbonate, 100% of the total charged amount) ) Were added in two dropping funnels in 30 minutes and 25 minutes, respectively. After heating and holding at 90 ° C. for 63 minutes, unreacted ECR was recovered by distillation at 102 ° C. and 70 minutes. The recovered distillate was 61 g, and 10 g of ECR was contained therein. By GC analysis of the obtained reaction mixture, 70.8 g of TMP and 16 g of di-TMP were calculated. The yield based on ECR standards of the raw materials was 62.5% for TMP and 15.1% for di-TMP, respectively.

  High-purity di-TMP is effectively used as a raw material for polyacrylates, polyether polyols, polyurethanes, alkyd resins, synthetic lubricating oils and the like. By the method of the present invention, di-TMP can be obtained efficiently.

Claims (9)

A method for producing ditrimethylolpropane, which comprises reacting 2-ethyl-2-propenal with formaldehyde and a base. The method for producing ditrimethylolpropane according to claim 1, wherein 2-ethyl-2-propenal, at least one component of formaldehyde and a base are partially charged before the start of the reaction, and the remainder is added after the reaction. The method for producing ditrimethylolpropane according to claim 1, wherein at least one component of 2-ethyl-2-propenal and formaldehyde is partially charged before the start of the reaction, and the remainder and a base are added and reacted. The ditrimethylol according to any one of claims 1 to 3, wherein a part of 2-ethyl-2-propenal is 10 to 100% of the total amount of 2-ethyl-2-propenal. Propane production method. The method for producing ditrimethylolpropane according to any one of claims 1 to 4, wherein a part of formaldehyde is 10 to 100% of the total amount of formaldehyde. The ditrimethylolpropane according to any one of claims 1 to 5, wherein the total amount of formaldehyde is 2.0 to 10.0 mol with respect to 1.0 mol of the total amount of 2-ethyl-2-propenal. Manufacturing method. The method for producing ditrimethylolpropane according to any one of claims 1 to 6, wherein an equivalent of a part of the base is 10 to 90% with respect to a total equivalent of the base. The method for producing ditrimethylolpropane according to any one of claims 1 to 7, wherein the total equivalent of the base is 0.5 to 2.5 equivalents with respect to a total of 1.0 mol of 2-ethyl-2-propenal. . The method for producing ditrimethylolpropane according to any one of claims 1 to 8, wherein an unreacted product of 2-ethyl-2-propenal and formaldehyde is recovered and reused.