KR102321091B1 - Separation method of dimethylolbutanal and preparation method of trimethylolpropane - Google Patents

Abstract

The present specification is (A) n-butylaldehyde (n-BAL) and formaldehyde (FA) react under an alkylamine catalyst, dimethylol butanal containing dimethylol butanal (DMB) and trimethylol propane (TMP) obtaining a mixed product; and (B) extracting dimethylolbutanal and trimethylolpropane with an efficiency of 95% or more and 80% or more, respectively, using a countercurrent extraction method using an organic solvent from the dimethylolbutanal mixture product, wherein the In step (B), the flow rate of the organic solvent is 70 to 110 g/min, the flow rate of the dimethylolbutanal mixture is 40 to 70 g/min, and the weight ratio of the organic solvent to the dimethylolbutanal mixture product is It relates to a method for separating dimethylol butanal that is 1.2 to 3.

Description

Separation method of dimethylol butanal and manufacturing method of trimethylol propane using the same

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

Trimethylolpropane (TMP) can be prepared by various methods, one of which is through the Cannizzaro reaction as follows.

<Cannizzaro Reaction>

In this case, it is prepared using an alkali metal base, but it is not efficient because 1 equivalent of a formate salt is produced 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 separating dimethylol butanal and a method for preparing trimethylolpropane using the same.

An exemplary embodiment of the present specification includes (A) n-butylaldehyde (n-BAL) and formaldehyde (FA) reacted under an alkylamine catalyst, including dimethylolbutanal (DMB) and trimethylolpropane (TMP) obtaining a dimethylol butanal mixture product; and (B) extracting dimethylolbutanal and trimethylolpropane with an efficiency of 95% or more and 80% or more, respectively, using a countercurrent extraction method using an organic solvent from the dimethylolbutanal mixture product, wherein the In step (B), the flow rate of the organic solvent is 70 to 110 g/min, the flow rate of the dimethylolbutanal mixture is 40 to 70 g/min, and the weight ratio of the organic solvent to the dimethylolbutanal mixture product is It provides a method for separating dimethylol butanal that is 1.2 to 3.

In addition, an exemplary embodiment of the present specification includes the steps of obtaining dimethylol butanal separated according to the above-described separation method of dimethylol butanal; And a method of producing trimethylolpropane comprising the step of preparing trimethylolpropane (TMP) in a yield of 80% or more by hydrogenating under the conditions of 100 ° C. to 140 ° C. and 20 bar to 40 bar under a copper-based hydrogenation catalyst. to provide.

Through the separation method of 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 chart for carrying out a method for separating dimethylol butanal and a method for preparing trimethylolpropane 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 theoretically expected maximum production amount.

An exemplary embodiment of the present specification is (A) by reacting n-butylaldehyde (hereinafter n-BAL) and formaldehyde (hereinafter FA) under an alkylamine catalyst, dimethylol butanal (hereinafter, dimethylol butanal) DMB) and trimethylol propane (trimethylol propane, hereinafter TMP) to obtain a mixed product comprising a dimethylol butanal; and (B) extracting dimethylolbutanal and trimethylolpropane with an efficiency of 95% or more and 80% or more, respectively, using a countercurrent extraction method using an organic solvent from the dimethylolbutanal mixture product, wherein the In step (B), the flow rate of the organic solvent is 70 to 110 g/min, the flow rate of the dimethylolbutanal mixture is 40 to 70 g/min, and the weight ratio of the organic solvent to the dimethylolbutanal mixture product is It provides a method for separating dimethylol butanal that is 1.2 to 3.

As DMB and some TMP are formed after the aldol reaction, salts are formed, 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.

Accordingly, in the separation method of dimethylol butanal according to an exemplary embodiment of the present specification, DMB, a desired material, can be effectively extracted using countercurrent extraction. can get

In particular, in the case of the Cannizzaro reaction for producing TMP, TMP is produced through the reaction of n-BAL, 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.

In addition, in the separation method of dimethylol butanal according to an exemplary embodiment of the present specification, countercurrent extraction uses multi-stage extraction, and controls the flow rate and/or reaction conditions of the raw material during extraction to obtain high extraction efficiency of DMB. can be effectively extracted.

Dimethylolbutanal is heat sensitive, and distillation in general is a very energy consuming technique. Therefore, according to an exemplary embodiment of the present specification, by using extraction feasible at a lower temperature than the separation method by distillation of dimethylol butanal, heat-sensitive dimethylol butanal is protected from decomposition into small molecules, and further Energy can also be reduced.

In the separation method of dimethylol butanal according to an exemplary embodiment of the present specification, in step (A), n-butylaldehyde, formaldehyde, and an alkylamine catalyst are used to perform an aldol condensation reaction to dimethylol butanal mixed product to obtain

According to an exemplary embodiment of the present specification, in step (A), 100 parts by weight of n-butylaldehyde, 250 to 450 parts by weight of formaldehyde, and 10 to 40 parts by weight of an alkylamine catalyst are introduced into a jacket type reactor. . At this time, n-butylaldehyde, formaldehyde, and an alkylamine catalyst may be simultaneously introduced into the reactor, and some of these may be introduced into the reactor first. For example, in order to further improve reaction efficiency, it is preferable to add n-butylaldehyde and an alkylamine catalyst after first introducing formaldehyde into the reactor.

In addition, according to an exemplary embodiment of the present specification, the content of the reactant included in the reactor in step (A) is 250 to 450 parts by weight of formaldehyde, 10 to 40 parts by weight of an alkylamine catalyst, based on 100 parts by weight of n-butylaldehyde. parts, and more preferably 290 to 390 parts by weight of formaldehyde and 25 to 35 parts by weight of an alkylamine catalyst based on 100 parts by weight of n-butylaldehyde.

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), tributylamine (tributylamine) and the like may be used, and preferably triethylamine (TEA) may be used.

According to an exemplary embodiment of the present specification, the reactor in step (A) may use a jacket type reactor, but is not limited thereto.

In addition, according to an exemplary embodiment of the present specification, the reaction temperature in step (A) may be preferably 20 ℃ to 70 ℃, more preferably 25 ℃ to 40 ℃. The reaction time is preferably 90 minutes to 200 minutes.

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, and a solvent. At this time, the weight ratio of DMB and TMP contained in the dimethylol butanal mixture product may be 3:1 to 25:1, preferably 5:1 to 25:1, and more preferably 5:1. to 20:1. The solvent may be pure or organic.

According to an exemplary embodiment of the present specification, in step (B), DMB is extracted using an organic solvent from the dimethylol butanal mixture obtained in step (A). At this time, an alcohol having 2 to 10 carbon atoms may be used as the organic solvent, preferably an alcohol having 2 to 8 carbon atoms, more preferably an alcohol having 8 carbon atoms, more preferably 2-ethylhexanol (2-ethylhexanol) , hereinafter 2-EH) may be used as an organic solvent.

In addition, according to an exemplary embodiment of the present specification, a counter-current type extraction device is used for the extraction device used in step (B), and the counter-current type extraction may be a multi-stage extraction including two or more stages. and preferably 30 to 60 stages, and more preferably 30 to 50 stages. When the number of stages is less than 30, a small amount of components other than the extract may remain in the extraction solvent, and when the number of stages is less than 60, there are disadvantages in terms of time and cost of the process due to too many stages.

According to an exemplary embodiment of the present specification, the extraction temperature in step (B) is preferably 20° C. to 75° C., specifically preferably 25° C. to 70° C., and more specifically preferably 50° C. to 70° C. do. In addition, the extraction time is preferably 30 minutes to 90 minutes.

According to an exemplary embodiment of the present specification, when the organic solvent, extraction temperature, extraction time, extraction type, and number of stages in step (B) are within the above preferred ranges, extraction conditions are optimized so that DMB is substantially lost by extraction It can be extracted with a DMB extraction efficiency of 95% or more.

According to an exemplary embodiment of the present specification, the flow rate of the organic solvent in step (B) may be 70 to 110 g/min, more preferably 75 to 105 g/min. When the flow rate of the organic solvent is less than 70 g/min, there is a disadvantage in that the action effect of the extraction solvent in the extraction process is lowered, and when it is more than 110 g/min, the flow rate of the organic solvent is high and it is in contact with the extract in countercurrent extraction. As the time is shortened, there is a disadvantage in that the extraction efficiency is reduced.

According to an exemplary embodiment of the present specification, the flow rate of the dimethylol butanal mixture product in step (B) may be 40 to 70 g/min. If the flow rate of the dimethylolbutanal mixture product is less than 40 g/min, the extraction time is long and the process is not economical. As the time is shortened, there is a disadvantage in that the extraction efficiency is reduced.

According to an exemplary embodiment of the present specification, the weight ratio of the organic solvent to the dimethylol butanal mixture in step (B) may be from 1.2 to 3, more preferably from 1.5 to 2. When the weight ratio of the organic solvent to the dimethylol butanal mixture product satisfies the above range, the contact area, contact time, extraction action, etc. of the organic solvent as the extraction solvent and the dimethylol butanal mixture product as the extraction raw material are optimal. In this state, extraction efficiency is maximized.

In particular, according to an exemplary embodiment of the present specification, in step (B), the flow rate of the organic solvent, the flow rate of the dimethylolbutanal mixture, and the weight ratio of the organic solvent to the dimethylolbutanal mixture are calculated as described above. When it is within the preferred range, DMB can be recovered with an extraction efficiency of 95% or more, preferably 97% or more, more preferably 97.2% or more, from the dimethylolbutanal mixture product obtained in step (A). More preferably, it can be recovered with an extraction efficiency of 97.7% or more, and TMP can be recovered with an extraction efficiency of 80% or more, preferably an extraction efficiency of 82% or more, and more preferably an extraction efficiency of 82.6% or more.

In addition, according to an exemplary embodiment of the present specification, the step (B) may further include a step of stirring.

The stirring may be performed through a stirring device mounted inside the extractor.

The stirring temperature of the stirring step may be 20 °C to 70 °C, more preferably 25 °C to 40 °C.

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

According to an exemplary embodiment of the present specification, when the step of stirring in the (B) extraction step is further included, the DMB extraction efficiency can be further maximized.

According to an exemplary embodiment of the present specification, obtaining DMB separated according to the above-described separation method of dimethylol butanal; And it provides a method for producing trimethylolpropane comprising the step of preparing TMP in a yield of 80% or more by hydrogenation under the conditions of 100 ° C. to 140 ° C. and 20 bar to 40 bar under a copper-based hydrogenation catalyst.

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,

In addition, according to an exemplary embodiment of the present specification, the copper-based hydrogenation catalyst used in the method for preparing trimethylolpropane may be a copper-based base catalyst, and is not limited as long as it is a catalyst used in the hydrogenation reaction.

In addition, according to an exemplary embodiment of the present specification, the hydrogenation reaction time in the method for producing trimethylolpropane may be 5 to 10 hours, more preferably 6 to 9 hours.

In addition, according to an exemplary embodiment of the present specification, in the method for preparing trimethylolpropane, TMP may be prepared in a yield of 80% or more, preferably in a yield of 84% or more, more preferably 84.8% or more It can be prepared in yield.

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. At this time, the organic solvent used in the purification step may be the same as the above-described extraction solvent, but is not limited thereto.

A method for separating dimethylol butanal and a method for preparing trimethylolpropane according to an exemplary embodiment of the present specification are schematically shown below.

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

According to FIG. 1 , FA is fed through a pipe 11 , n-BAL is fed through a pipe 12 , and an alkylamine catalyst is introduced into the reactor 1 through a pipe 13 . At this time, FA, n-BAL, and the alkylamine catalyst may be simultaneously introduced, and after a certain amount of FA is first introduced into the reactor, the n-BAL and the alkylamine catalyst may be introduced into the reactor. In this case, relative to 100 parts by weight of n-BAL, 250 to 450 parts by weight of FA and 10 to 40 parts by weight of an alkylamine catalyst are added. After completion of the addition, the reaction is performed at a reaction temperature of 20° C. to 70° C. for a reaction time of 90 minutes to 200 minutes to obtain a mixed product of dimethylol butanal. At this time, an aldol reaction may occur in the reactor 1 .

Next, the dimethylol butanal mixed product obtained above is introduced into the multi-stage extractor 2 through the pipe 14 . The organic solvent of alcohol having 2 to 10 carbon atoms as the extraction solvent is supplied to the multi-stage extractor 2 through the pipe 19 . At this time, the number of stages of the multi-stage extractor 2 has 30 to 60 stages. Then, at an extraction temperature of 20° C. to 75° C. for an extraction time of 30 minutes to 90 minutes, the flow rate of the organic solvent is 70 to 110 g/min, the flow rate of the dimethylol butanal mixture product is 40 to 70 g/min, the dimethylol The weight ratio of the organic solvent to the butanal mixture product is 1.2 to 3, and DMB is extracted. At this time, the multi-stage extractor 2 may include a stirring device. When the step of stirring is included in the extraction step, the stirring may be performed at a stirring speed of 150 to 350 rpm.

When the flow rate of the organic solvent, the flow rate of the dimethylolbutanal mixture product, and the weight ratio of the organic solvent to the dimethylolbutanal mixture product are within the above preferred ranges, the multi-stage extractor 2 extracts DMB can be recovered with an extraction efficiency of 95% or more, preferably an extraction efficiency of 97% or more, more preferably an extraction efficiency of 97.2% or more, and TMP is recovered with an extraction efficiency of 80% or more, preferably an extraction efficiency of 82% or more, more preferably It can be recovered with an extraction efficiency of 82.6% or more.

The extracted DMB is discharged from the multi-stage extractor 2 through the pipe 15 . The extracted TMP is discharged from the multi-stage extractor 2 through the pipe 21 . Except for DMB and TMP obtained through the extraction step in the multi-stage extractor (2), FA and TEA, which are the reaction raw materials of the aldol reaction, are fed back into the reactor (1) through the pipe (18).

Next, the DMB obtained above is introduced into the hydrogenation reactor (3) through the pipe (15). At this time, the hydrogenation reactor 3 may be a batch type reactor. For the hydrogenation reaction, a copper-based hydrogenation catalyst is supplied to the hydrogenation reactor 3 through a pipe 20 . Thereafter, the hydrogenation reaction is carried out under the conditions of a hydrogenation reaction temperature of 100° C. to 140° C. and a reaction pressure of 20 bar to 40 bar to prepare TMP. The obtained TMP is discharged from the hydrogenation reactor (3) through a pipe (16).

Next, the TMP obtained through the hydrogenation reaction is introduced into the purifier 4 through the pipe 16, and high-purity TMP is obtained through purification. The obtained TMP is recovered through the pipe 17 , and the organic solvent used for purification is introduced into the multi-stage extractor 2 through the pipe 19 . In this case, the organic solvent used for purification is preferably the same as the extraction solvent.

As described above, according to an exemplary embodiment of the present specification, after the aldol reaction in the TMP manufacturing method, DMB, which is a material of the pre-TMP step, is effectively separated through countercurrent multi-stage extraction. In particular, in the countercurrent multi-stage extraction step, by selecting the optimal extraction solvent and extraction conditions (flow rate, flow weight ratio, extraction temperature, etc.) can

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.

< manufacturing example 1> Extract raw material 1

1 kg of n-BAL, 3.9 kg of FA, and 0.3 kg of triethylamine were prepared as the extraction raw material 1.

< manufacturing example 2> Extract raw material 2

1 kg of n-BAL, 2.9 kg of FA, and 0.3 kg of triethylamine were prepared as the extraction raw material 2.

< Example 1>

The extraction raw material 1 prepared in Preparation Example 1 was put into a 10L jacket type reactor, stirred at a reaction temperature of 35° C., and reacted for 3 hours to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 101 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 67 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture was 1.5. Extraction was carried out at an extraction temperature of 70° C. using a 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 200 rpm using a stirrer in the extractor. DMB and TMP were obtained as extracts.

< Example 2>

The extraction raw material 1 prepared in Preparation Example 1 was put into a 10L jacket type reactor, stirred at a reaction temperature of 35° C., and reacted for 3 hours to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 77 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 51 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture product was 1.5. Extraction was carried out at an extraction temperature of 70° C. using a 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 300 rpm using a stirring device in the extractor. DMB and TMP were obtained as extracts.

< Example 3>

The extraction raw material 1 prepared in Preparation Example 1 was put into a 10L jacket type reactor, stirred at a reaction temperature of 35° C., and reacted for 3 hours to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 84 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 42 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture was 2. Extraction was performed at an extraction temperature of 50° C. using a 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 300 rpm using a stirring device in the extractor. DMB and TMP were obtained as extracts.

< Example 4>

The extraction raw material 2 prepared in Preparation Example 2 was put into a 10L jacket type reactor, and the mixture was reacted for 3 hours by stirring at a reaction temperature of 35° C. to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 86 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 43 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture was 2. Extraction was carried out at an extraction temperature of 25° C. using 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 200 rpm using a stirrer in the extractor. DMB and TMP were obtained as extracts.

< Example 5>

The extraction raw material 2 prepared in Preparation Example 2 was put into a 10L jacket type reactor, and the mixture was reacted for 3 hours by stirring at a reaction temperature of 35° C. to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 86 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 43 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture was 2. Extraction was performed at an extraction temperature of 50° C. using a 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 200 rpm using a stirrer in the extractor. DMB and TMP were obtained as extracts.

< Example 6>

The extraction raw material 1 prepared in Preparation Example 1 was put into a 10L jacket type reactor, stirred at a reaction temperature of 35° C., and reacted for 3 hours to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 77 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 51 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture was 1.5. Extraction was performed at an extraction temperature of 70° C. using a 30-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 300 rpm using a stirring device in the extractor. DMB and TMP were obtained as extracts.

< comparative example 1>

The extraction raw material 1 prepared in Preparation Example 1 was put into a 10L jacket type reactor, stirred at a reaction temperature of 35° C., and reacted for 3 hours to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 66 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 66 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture product was 1. Extraction was carried out at an extraction temperature of 25° C. using 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 200 rpm using a stirrer in the extractor. DMB and TMP were obtained as extracts.

< comparative example 2>

The extraction raw material 2 prepared in Preparation Example 2 was put into a 10L jacket type reactor, and the mixture was reacted for 3 hours by stirring at a reaction temperature of 35° C. to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 22 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 22 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture product was 1. Extraction was carried out at an extraction temperature of 25° C. using 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 200 rpm using a stirrer in the extractor. DMB and TMP were obtained as extracts.

< comparative example 3>

The extraction raw material 2 prepared in Preparation Example 2 was put into a 10L jacket type reactor, and the mixture was reacted for 3 hours by stirring at a reaction temperature of 35° C. to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 34 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 34 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture product was 1. Extraction was carried out at an extraction temperature of 25° C. using 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 200 rpm using a stirrer in the extractor. DMB and TMP were obtained as extracts.

< comparative example 4>

The extraction raw material 2 prepared in Preparation Example 2 was put into a 10L jacket type reactor, and the mixture was reacted for 3 hours by stirring at a reaction temperature of 35° C. to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 67 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 67 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture product was 1. Extraction was carried out at an extraction temperature of 25° C. using 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 100 rpm using a stirrer in the extractor. DMB and TMP were obtained as extracts.

< comparative example 5>

The extraction raw material 1 prepared in Preparation Example 1 was put into a 10L jacket type reactor, stirred at a reaction temperature of 35° C., and reacted for 3 hours to synthesize a dimethylol butanal mixture.

The synthesized dimethylolbutanal mixture was used as a feed for extraction, and 2-EH was used as an extraction solvent. At this time, the flow rate of 2-EH was 72 g/min, the flow rate of the synthesized dimethylolbutanal mixture was 66 g/min, and the weight ratio of 2-EH to the dimethylolbutanal mixture was 1.1. Extraction was carried out at an extraction temperature of 25° C. using 50-stage extraction equipment of a counter-current type. During extraction, it was stirred at a stirring speed of 200 rpm using a stirrer in the extractor. DMB and TMP were obtained as extracts.

The extraction results (extraction efficiency) obtained in Examples 1 to 6 and Comparative Examples 1 to 5 are shown in Table 1 below.

division extraction
singular extraction
Raw material Flow rate (g/min) Solvent/feed ratio
(g/g) Agitator speed
(rpm) extraction temperature
(℃) Extraction Efficiency (%) Feed 2-EH DMB TMP Example 1 50 raw material 1 67 101 1.5 200 70 99.6 97.2 Example 2 50 raw material 1 51 77 1.5 300 70 99.8 98.6 Example 3 50 raw material 1 42 84 2 300 50 99.3 96.4 Example 4 50 raw material 2 43 86 2 200 25 97.7 82.6 Example 5 50 raw material 2 43 86 2 200 50 97.7 89.7 Example 6 30 raw material 1 51 77 1.5 300 70 97.2 90.9 Comparative Example 1 50 raw material 1 66 66 One 200 25 93.4 64.1 Comparative Example 2 50 raw material 2 22 22 One 200 25 86.4 69.5 Comparative Example 3 50 raw material 2 34 34 One 200 25 88. 63 Comparative Example 4 50 raw material 2 67 67 One 100 25 87 67.4 Comparative Example 5 50 raw material 1 66 72 1.1 200 25 94.1 70.3

< Example 7>

A copper-based hydrogenation catalyst and DMB in the extract obtained in Example 3 were added as raw materials to a batch type hydrogenation reactor, and hydrogenation reaction was performed at 115° C. and 30 bar for 8 hours, and then TMP was finally obtained through a purification process. .

< comparative example 6>

The extraction raw material 1 prepared in Preparation Example 1 was put into a 10L jacket type reactor, stirred at a reaction temperature of 35° C., and reacted for 3 hours to synthesize a dimethylol butanal mixture.

The obtained diketylol butanal mixed product was put into a batch type hydrogenation reactor without an extraction process, together with a copper-based hydrogenation catalyst, and hydrogenation was performed at 115° C. and 30 bar for 8 hours, and then TMP was finally obtained through a purification process. .

The final results according to Example 7 and Comparative Example 6 are shown in Table 2 below.

division Hydrogenation reaction raw material TMP yield (%) Example 7 DMB of Example 3 84.8 Comparative Example 6 of the extraction raw material 1 (Preparation Example 1)
Aldol reaction product (extraction X) 50.7

According to Examples 1 to 6 and Comparative Examples 1 to 5, the type of organic solvent, the flow rate of the organic solvent, and the flow rate of the dimethylol butanal mixture product in the countercurrent multi-stage extraction of the dimethylol butanal mixture by the aldol reaction , it can be seen that by controlling the weight ratio of the organic solvent to the mixed product of dimethylol butanal, the extraction temperature, etc., DMB as a material prior to TMP can be effectively extracted with an extraction efficiency of 95% or more.

According to Examples 1 to 6, the DMB extraction efficiency was 97.2% or more, indicating a significantly higher DMB extraction efficiency compared to Comparative Examples 1 to 5. In addition, the TMP extraction efficiency is 82.6% or more, indicating a significantly higher TMP extraction efficiency compared to Comparative Examples 1 to 5.

In Comparative Example 5, the flow rate of the organic solvent and the flow rate of the dimethylolbutanal mixture were included in the scope of the present invention, but in Comparative Example 5 where the weight ratio of the organic solvent to the dimethylolbutanal mixture was 1.1, As compared to Examples 1 to 6, it can be seen that the DMB extraction efficiency is lowered.

According to Example 7 and Comparative Example 6, when DMB is extracted with high purity after the aldol reaction and then hydrogenated, a higher TMP yield of 80% or more can be obtained compared to the case where the extraction process is not performed after the aldol reaction. could check

As a result, in countercurrent multi-stage extraction, by selecting the optimal extraction solvent and extraction conditions (flow rate, flow weight ratio, extraction temperature, etc.) Finally, it was possible to maximize the TMP yield through the reaction.

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. .

1: Reactor
2: Multi-stage extractor
3: Hydrogenation reactor
4: Purifier
11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21: pipe

Claims (11)

(A) n-butylaldehyde (n-BAL) and formaldehyde (FA) are reacted under an alkylamine catalyst to obtain a dimethylolbutanal mixture product containing dimethylolbutanal (DMB) and trimethylolpropane (TMP) obtaining; and
(B) extracting dimethylolbutanal and trimethylolpropane with an efficiency of 95% or more and 80% or more, respectively, using a countercurrent extraction method using an organic solvent from the dimethylolbutanal mixture product,
In step (B), the flow rate of the organic solvent is 70 to 110 g/min, the flow rate of the dimethylolbutanal mixture is 40 to 70 g/min, and the weight ratio of the organic solvent to the dimethylolbutanal mixture product A method for separating dimethylol butanal is 1.2 to 3. The method according to claim 1, wherein in step (A), 100 parts by weight of n-butylaldehyde and 250 to 450 parts by weight of formaldehyde are reacted in the presence of 10 to 40 parts by weight of an alkylamine catalyst. The method according to claim 1, wherein the weight ratio of dimethylolbutanal and trimethylolpropane in the dimethylolbutanal mixture product of step (A) is 3:1 to 25:1. The method according to claim 1, wherein the countercurrent extraction method is a multi-stage extraction method having two or more stages. The method according to claim 1, wherein the countercurrent extraction method is a multi-stage extraction method of 30 to 60 stages. The method according to claim 1, wherein the organic solvent is an alcohol having 2 to 10 carbon atoms. The method of claim 1, wherein the organic solvent is 2-ethyl hexanol. The method according to claim 1, wherein the extraction in step (B) is performed at an extraction temperature of 20 °C to 75 °C. The method according to claim 1, wherein step (B) further comprises the step of stirring. The method for separating dimethylol butanal according to claim 9, wherein the stirring speed of the stirring is 150 to 350 rpm. Obtaining a dimethylol butanal separated according to the method for separating dimethylol butanal of any one of claims 1 to 10; and
Method for producing trimethylolpropane comprising the step of preparing trimethylolpropane (TMP) in a yield of 80% or more by performing a hydrogenation reaction at a temperature of 100°C to 140°C and a pressure of 20 bar to 40 bar under a copper-based hydrogenation catalyst .

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