KR102359896B1 - Preparing method of dimethylolbutanal and preparation method of trimethylolpropane using the same - Google Patents

Abstract

The present specification relates to (A) reacting n-butylaldehyde (n-BAL) and formaldehyde (FA) under an alkylamine catalyst to obtain a dimethylol butanal mixture product containing dimethylol butanal (DMB); and (B) separating dimethylol butanal from the dimethylol butanal mixture by extraction using alkyl acetate, and preparation of trimethylol propane using the same it's about how

Description

Manufacturing method of dimethylol butanal and trimethylol propane using the same

The present specification relates to a method for preparing dimethylol butanal and a method for preparing trimethylolpropane using the same.

Trimethylolpropane (TMP) can be prepared in a variety of ways, one of which is n-butylaldehyde (n-BAL) and formaldehyde (FA) as follows Cannizzaro under an alkali metal (mainly, NaOH) catalyst This is done through a reaction.

The TMP production method by the Cannizzaro reaction, which is mainly used in the commercialization process, is not efficient because 1 mol of metal formate per 1 mol of TMP is generated as a by-product.

Trimethylolpropane is a white crystalline material at room temperature, and is widely used as a raw material in various fields such as alkyd resins, saturated polyesters, synthetic lubricants, polyurethane resins, and plasticizer fields. Therefore, research to produce trimethylolpropane, an industrially important raw material, in an economical way is continuously being conducted.

US Patent Publication No. 3956306

The present specification provides a method for preparing dimethylol butanal and a method for preparing trimethylolpropane using the same.

An exemplary embodiment of the present specification is,

(A) reacting n-butylaldehyde (n-BAL) and formaldehyde (FA) under an alkylamine catalyst to obtain a dimethylolbutanal mixture product including dimethylolbutanal (DMB); and

(B) provides a method for producing dimethylol butanal, comprising the step of separating dimethylol butanal from the dimethylol butanal mixture using extraction using alkyl acetate.

In addition, an exemplary embodiment of the present specification,

Obtaining dimethylol butanal according to the manufacturing method of dimethylol butanal; and

It provides a method for producing trimethylolpropane comprising the step of preparing trimethylolpropane (TMP) by performing a hydrogenation reaction at a temperature of 80°C to 150°C and a pressure of 20bar to 70bar under a metal catalyst.

Through the method for producing dimethylol butanal according to an exemplary embodiment of the present specification, dimethylol butanal used as a raw material for preparing trimethylol propane can be obtained with high extraction efficiency.

Furthermore, trimethylolpropane can be obtained with high efficiency by using the obtained dimethylolbutanal as a raw material for the hydrogenation reaction.

1 is a process diagram for carrying out a method for producing dimethylol butanal according to an exemplary embodiment of the present specification.

Hereinafter, the present specification will be described in more detail.

In the present specification, 'extraction efficiency' is defined as the ratio of the weight of the extract contained in the extraction solvent after extraction to the weight of the desired extract contained in the input extraction raw material.

In addition, in the present specification, 'yield' is defined as a value obtained by dividing the amount of product actually produced in the reaction by the theoretical maximum yield.

An exemplary embodiment of the present specification is (A) n-butylaldehyde (n-BAL) and formaldehyde (FA) are reacted under an alkylamine catalyst to produce a dimethylol butanal mixture product containing dimethylol butanal (DMB) obtaining; and (B) separating dimethylol butanal from the dimethylol butanal mixture using extraction using alkyl acetate.

In the case of the Cannizzaro reaction for producing TMP, n-BAL is reacted to produce TMP, and a formate salt is produced together as a by-product. However, in the method for producing trimethylolpropane according to the present specification, DMB is separated by an extraction method after the aldol reaction, and then TMP is produced through a hydrogenation process, so no by-products are produced.

As DMB and some TMP are formed after the aldol reaction, salts are generated, and if this is not removed, the reactivity and stability in the subsequent hydrogenation reaction are reduced. When trimethylolpropane is produced by hydrogenation, effective separation of dimethylolbutanal (DMB), a material in the previous stage of trimethylolpropane, is required after the first-stage aldol reaction.

In particular, the present inventors found that among various solvents used for extraction, alkyl acetate exhibited high DMB extraction efficiency compared to other solvents. Since DMB contains two hydroxyl groups (-OH), it is readily soluble in polar solvents. Since the alkyl acetate used in the present invention, especially ethyl acetate, has a greater polarity than other hydrocarbon solvents or 2-ethylhexanol (2-EH) used as the extraction solvent, the extraction solvent during extraction using a separatory funnel When used as a DMB, it is possible to maximize the DMB extraction efficiency.

Accordingly, in the method for producing dimethylol butanal according to an exemplary embodiment of the present specification, DMB, a desired material, can be effectively produced by extraction using alkyl acetate as a solvent, and ultimately, the subsequent hydrogenation reaction is performed. In this case, it was possible to obtain a high-efficiency TMP yield.

According to an exemplary embodiment of the present specification, the alkyl acetate as the extraction solvent may be an alkyl acetate having 2 to 10 carbon atoms, preferably an alkyl acetate having 2 to 6 carbon atoms, more preferably ethyl acetate. can be

In the method for producing dimethylol butanal according to an exemplary embodiment of the present specification, in step (A), dimethylol butanal is included through an aldol condensation reaction using n-butylaldehyde, formaldehyde, and an alkylamine catalyst. A mixture of dimethylol butanal is obtained.

According to an exemplary embodiment of the present specification, in step (A), 100 parts by weight of n-butylaldehyde, 200 to 400 parts by weight of formaldehyde, and 10 to 40 parts by weight of an alkylamine catalyst are reacted to obtain a dimethylol butanal mixture product. can do. In this case, the reactor may be a jacket type reactor, but is not limited thereto.

The n-butylaldehyde, formaldehyde, and the alkylamine catalyst may be simultaneously introduced into the reactor, or some of these may be introduced into the reactor first. For example, in order to further improve the reaction efficiency, it is preferable to slowly introduce the alkylamine catalyst after first introducing n-butylaldehyde and formaldehyde into the reactor.

In addition, according to an exemplary embodiment of the present specification, the alkylamine catalyst in step (A) is an alkylamine having 3 to 20 carbon atoms, and specifically, trimethylamine, triethylamine (TEA), tripropylamine (tripropylamine), or diisopropylethylamine (diisopropylethylamine) may be used, preferably triethylamine may be used.

According to an exemplary embodiment of the present specification, the reaction temperature in step (A) may be 15 °C to 70 °C, preferably 20 °C to 50 °C. More preferably, it may be 25°C to 40°C.

In addition, according to an exemplary embodiment of the present specification, the reaction time of step (A) may be 90 minutes to 200 minutes, preferably 120 minutes to 200 minutes.

According to an exemplary embodiment of the present specification, after the reaction of step (A), the step of lowering the temperature of the dimethylol butanal mixture to room temperature may be further included.

According to an exemplary embodiment of the present specification, the method may further include a step of adding n-butylaldehyde, formaldehyde, and an alkylamine catalyst to the reactor in step (A), followed by stirring. At this time, the stirring temperature may be 20 °C to 70 °C, more preferably 25 °C to 40 °C.

In the step (A), n-butylaldehyde, formaldehyde, and an alkylamine catalyst are added to the reactor, and then stirred at the same time as the reaction may be performed. That is, the reaction and stirring may be performed simultaneously.

In addition, according to an exemplary embodiment of the present specification, the stirring speed of the stirring in step (A) may be 150 to 350 rpm, more preferably 200 to 300 rpm.

According to an exemplary embodiment of the present specification, the dimethylol butanal mixture product obtained as a result of step (A) may include DMB, TMP, FA and H ₂ O. In this case, based on the dimethylol butanal mixture product, DMB may be 20 to 30 wt%, TMP may be 4 to 12 wt%, FA may be 15 to 25 wt%, and H ₂ O may be 38 to 45 wt%. can

According to an exemplary embodiment of the present specification, in step (B), from the dimethylol butanal mixture obtained in step (A), DMB is extracted using an alkylacetate.

According to an exemplary embodiment of the present specification, the extraction used in step (B) may be an extraction method using a separatory funnel, but is not limited thereto.

According to an exemplary embodiment of the present specification, the extraction temperature in step (B) is preferably 20° C. to 50° C., and specifically preferably 25° C. to 30° C.

According to an exemplary embodiment of the present specification, the extraction time refers to the time to stand still after mixing the extraction raw materials, and may be from 10 minutes to 90 minutes, preferably from 10 minutes to 40 minutes.

According to an exemplary embodiment of the present specification, in step (B), the weight ratio of the alkyl acetate to the dimethylol butanal mixture may be 0.1 to 5. It may be preferably 0.2 to 4, more preferably 0.5 to 3.

When the weight ratio of alkyl acetate to the dimethylol butanal mixture satisfies the above range, the contact area, contact time, extraction action, etc. of the alkyl acetate as the extraction solvent and the dimethylol butanal mixture product as the extraction raw material are optimal. In this state, the extraction efficiency is maximized. In addition, specifically, when the weight ratio of the alkyl acetate to the dimethylol butanal mixture product is less than 0.1, the extract and the raffinate become a single phase in which they are not separated, or the extraction efficiency is significantly reduced, If it exceeds 5, the extraction efficiency is almost the same depending on the amount of alkyl acetate used, so it is not effective compared to the amount used.

According to an exemplary embodiment of the present specification, the extraction in step (B) may extract dimethylolbutanal with an efficiency of 59% or more. Preferably, it can be extracted with an efficiency of 73% or more. More preferably, it can be extracted with an efficiency of 80% or more.

In particular, according to an exemplary embodiment of the present specification, in the step (B), when an alkyl acetate is used as an extraction solvent and the weight ratio of the alkyl acetate to the dimethylol butanal mixture product is within the preferred range as described above, the ( From the dimethylolbutanal mixture product obtained in step A), DMB can be recovered with an extraction efficiency of 59% or more, preferably an extraction efficiency of 73% or more, and more preferably an extraction efficiency of 80% or more.

According to an exemplary embodiment of the present specification, obtaining DMB according to the above-described method for preparing dimethylol butanal; And it provides a method for producing trimethylolpropane comprising the step of preparing TMP by hydrogenation reaction under the conditions of a reaction temperature of 80 ° C. to 150 ° C. and a reaction pressure of 20 bar to 70 bar under a metal catalyst.

According to an exemplary embodiment of the present specification, the metal catalyst may be a copper-based metal catalyst. The copper-based metal catalyst is not limited as long as it is a catalyst used in the hydrogenation reaction.

According to an exemplary embodiment of the present specification, the reactor used in the method for producing trimethylolpropane may be a batch-type hydrogenation reactor, but is not limited thereto.

According to an exemplary embodiment of the present specification, the reaction temperature of the hydrogenation reaction may be 80 °C to 150 °C, preferably 100 °C to 140 °C, more preferably 110 °C to 130 °C.

According to an exemplary embodiment of the present specification, the reaction pressure of the hydrogenation reaction may be 20 bar to 70 bar. Preferably, it may be 25 bar to 50 bar.

According to an exemplary embodiment of the present specification, a molar ratio of hydrogen (H ₂ ) based on dimethylol butanal during the hydrogenation reaction may be 1 to 3. Preferably, it may be 1 to 2.

According to an exemplary embodiment of the present specification, in the step of preparing trimethylolpropane, trimethylolpropane may be prepared in a yield of 70% or more. It is possible to prepare trimethylolpropane in high yield by controlling the reaction conditions of the above-described hydrogenation reaction, a specific alcohol solvent, and the weight ratio of the alcohol solvent to the DMB.

According to an exemplary embodiment of the present specification, the method for preparing trimethylolpropane may further include a step of purifying trimethylolpropane after preparing it by a hydrogenation reaction.

1 is an exemplary process diagram of an apparatus and piping configuration for carrying out a method for producing dimethylol butanal and a method for producing trimethylolpropane according to an exemplary embodiment of the present specification.

According to FIG. 1 , FA and n-BAL are introduced into the reactor 100 through a pipe 11 , and an alkylamine catalyst is introduced through a pipe 12 , respectively. At this time, preferably, a certain amount of FA and n-BAL is first introduced into the reactor 100 through the pipe 11 , and then the alkylamine catalyst is slowly introduced into the reactor 100 through the pipe 12 . In addition, it is preferably added in an amount of 200 to 400 parts by weight of FA, and 10 to 40 parts by weight of an alkylamine catalyst, based on 100 parts by weight of n-BAL. After completion of the addition, the reaction is carried out at a reaction temperature of 15° C. to 70° C. for a reaction time of 90 minutes to 200 minutes to obtain a dimethylol butanal mixture.

Next, the dimethylol butanal mixture obtained above is introduced into the extractor 200 through the pipe 13 . As an extraction solvent, alkyl acetate having 2 to 10 carbon atoms is supplied to the extractor 200 through a pipe 18 . At this time, the extraction of the extractor 200 may be an extraction method using a separatory funnel. Thereafter, at an extraction temperature of 20° C. to 50° C. for an extraction time of 10 to 90 minutes, the weight ratio of alkylacetate to the mixed product of dimethylol butanal is 0.1 to 5, and DMB is extracted. The extracted DMB is discharged from the extractor 200 through the pipe 14 . Reaction raw materials (eg, FA, alkylamine) that are not extracted in the extractor 200 may be introduced back into the reactor 100 through the pipe 17 .

Next, the DMB obtained above is introduced into the hydrogenation reactor 300 through the pipe 14 . At this time, the hydrogenation reactor 300 may be a batch type reactor. The hydrogenation reaction is performed under the conditions of a reaction temperature of 80° C. to 150° C. and a reaction pressure of 20 bar to 70 bar under a metal catalyst, thereby preparing TMP. The obtained TMP is discharged from the hydrogenation reactor 300 through the pipe 15 , and raffinate remaining after extraction is discharged from the hydrogenation reactor 300 through the pipe 16 .

As described above, according to an exemplary embodiment of the present specification, after the aldol reaction in the TMP manufacturing method, DMB, a material in the pre-TMP step, is effectively separated through extraction. In particular, by selecting an optimal extraction solvent (ethyl acetate) and extraction conditions (weight ratio of alkyl acetate to dimethylol butanal mixed product), DMB can be effectively extracted, ultimately maximizing the TMP yield.

Hereinafter, examples will be given to describe the present specification in detail. However, the embodiments according to the present specification may be modified in various other forms, and the scope of the present specification is not to be construed as being limited to the embodiments described below. The embodiments of the present specification are provided to more completely explain the present specification to those of ordinary skill in the art.

<Example 1>

After putting 100 g of n-BAL and 280 g of FA into a 1L reactor, 28 g of triethylamine (TEA) was slowly added dropwise. A dimethylol butanal mixture was synthesized by reacting at a reaction temperature of 35° C. for 3 hours. Thereafter, the temperature was reduced to room temperature.

200 g of the obtained dimethylol butanal mixed product (feed) was put into a separatory funnel, and then 50 g of ethyl acetate was added as an extraction solvent. After hand shaking for 5 minutes, it was left for 30 minutes to separate the extract and the raffinate to separate the DMB.

<Example 2>

In Example 1, DMB was separated in the same manner as in Example 1, except that 100 g of ethyl acetate was added as an extraction solvent.

<Example 3>

In Example 1, DMB was separated in the same manner as in Example 1, except that 150 g of ethyl acetate was added as an extraction solvent.

<Example 4>

In Example 1, DMB was separated in the same manner as in Example 1, except that 300 g of ethyl acetate was added as an extraction solvent.

<Comparative Example 1>

In Example 1, DMB was separated in the same manner as in Example 1, except that 250 g of dichloromethane was added instead of ethyl acetate as an extraction solvent.

<Comparative Example 2>

In Example 1, DMB was separated in the same manner as in Example 1, except that 250 g of toluene was added instead of ethyl acetate as an extraction solvent.

<Comparative Example 3>

In Example 1, DMB was separated in the same manner as in Example 1, except that 100 g of 2-ethylhexanol was added instead of ethyl acetate as an extraction solvent.

<Comparative Example 4>

In Example 1, DMB was separated in the same manner as in Example 1, except that 150 g of 2-ethylhexanol was added instead of ethyl acetate as an extraction solvent.

<Comparative Example 5>

In Example 1, DMB was separated in the same manner as in Example 1, except that 100 g of tert-butylmethylether was added instead of ethyl acetate as an extraction solvent.

<Comparative Example 6>

In Example 1, DMB was separated in the same manner as in Example 1, except that 150 g of tert-butyl methylether was added instead of ethyl acetate as an extraction solvent.

<Comparative Example 7>

In Example 1, DMB was separated in the same manner as in Example 1, except that 100 g of methyl isobutyl ketone was added instead of ethyl acetate as an extraction solvent.

<Comparative Example 8>

In Example 1, DMB was separated in the same manner as in Example 1, except that 150 g of methyl isobutyl ketone was added instead of ethyl acetate as an extraction solvent.

The extraction results (extraction efficiency) obtained in Examples 1 to 4 and Comparative Examples 1 to 8 are shown in Table 1 below.

division extraction solvent
(solvent) Solvent/feed ratio
(g/g) DMB extraction efficiency (%) Example 1 ethyl acetate 0.25 59.5 Example 2 ethyl acetate 0.5 73.6 Example 3 ethyl acetate 0.75 81.9 Example 4 ethyl acetate 1.5 87.5 Comparative Example 1 dichloromethane 1.25 52.6 Comparative Example 2 toluene 1.25 1.0 Comparative Example 3 2-ethylhexanol 0.5 59.8 Comparative Example 4 2-ethylhexanol 0.75 64.2 Comparative Example 5 tert-butyl methylether 0.5 66.2 Comparative Example 6 tert-butyl methylether 0.75 71.8 Comparative Example 7 methyl isobutyl ketone 0.5 69.6 Comparative Example 8 methyl isobutyl ketone 0.75 75.8

According to Examples 1 to 4 and Comparative Examples 1 to 8, in the extraction of the dimethylol butanal mixture product by the aldol reaction using a separatory funnel, in comparison with the solvent used in Comparative Examples 1 to 8, Examples 1 to When ethyl acetate used in step 4 is used as an extraction solvent, DMB can be separated with high DMB extraction efficiency.

In addition, it can be seen that when the weight ratio of ethyl acetate to the mixed product of dimethylol butanal is adjusted during extraction, DMB can be effectively extracted as a material prior to TMP.

In particular, as in Example 2, when the weight ratio (Solvent/feed ratio) of ethyl acetate to the mixed product of dimethylol butanal is 0.5, it can be seen that the DMB extraction efficiency is higher than in Comparative Examples 3, 5, and 7.

As in Examples 3 and 4, when the weight ratio (Solvent/feed ratio) of ethyl acetate to the mixed product of dimethylol butanal is 0.75 to 1.5, it can be seen that the DMB extraction efficiency is significantly higher than in Comparative Examples 1 to 8.

As a result, by selecting the optimal extraction solvent and extraction conditions (weight ratio of ethyl acetate to the dimethylol butanal mixture), DMB, a material in the pre-TMP step, is effectively extracted, and ultimately through the subsequent hydrogenation reaction. can maximize the TMP yield.

Although preferred embodiments of the present invention have been described above, the present invention is not limited thereto, and it is possible to carry out various modifications within the scope of the claims and the detailed description of the invention, and this also falls within the scope of the invention. .

100: reactor
200: extractor
300: hydrogenation reactor
11, 12, 13, 14, 15, 16, 17, 18: pipe

Claims (12)

delete delete delete delete delete delete delete (A) reacting n-butylaldehyde (n-BAL) and formaldehyde (FA) under an alkylamine catalyst to obtain a dimethylolbutanal mixture product including dimethylolbutanal (DMB);
(B) separating dimethylol butanal from the dimethylol butanal mixture product by extraction using alkyl acetate; and
A method for producing trimethylolpropane comprising the step of preparing trimethylolpropane (TMP) by performing a hydrogenation reaction at a temperature of 80°C to 150°C and a pressure of 20bar to 70bar under a metal catalyst,
The weight ratio of the alkyl acetate to the dimethylol butanal mixture in step (B) is 0.1 to 5,
The extraction is a method for producing trimethylolpropane that extracts dimethylolbutanal with an efficiency of 59% or more. The method of claim 8, wherein the alkyl acetate is an alkyl acetate having 2 to 10 carbon atoms. The method of claim 8, wherein the alkyl acetate is ethyl acetate. The method according to claim 8, wherein in step (A), 100 parts by weight of n-butylaldehyde and 200 to 400 parts by weight of formaldehyde are reacted in the presence of 10 to 40 parts by weight of an alkylamine catalyst. The method for producing trimethylolpropane according to claim 8, wherein the extraction is extraction using a separatory funnel.

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