KR102224268B1 - Trimethylolpropane manufacturing device and method using thereof - Google Patents

Abstract

The present disclosure relates to an apparatus for producing trimethylol propane and a method for producing it, and more particularly, a) DMB (2,2-dimethyl) by reacting an aldol with n-butyraldehyde and formaldehyde in the presence of an amine compound as a catalyst. Aldol reactor to produce albutanal); b) a DMB purifier for removing some or all of moisture, formaldehyde, and methanol from the aldol reaction product including the DMB; c) a hydrogenation reactor for generating TMP (trimethylolpropane) by hydrogenating DMB from which moisture, formaldehyde and methanol have been removed; And d) a purification device for purifying the TMP; and an apparatus for producing trimethylolpropane and a manufacturing method using the same.
According to the present description, after the aldol reaction, moisture, formaldehyde and methanol in the aldol reaction product including DMB are removed, and the removed moisture and formaldehyde are reused for the aldol reaction, thereby reducing cost and preventing environmental pollution. Since the extractor and the organic solvent purification process are not required, the process is simplified and there is an effect of providing a low energy consumption process.

Description

Trimethylolpropane manufacturing apparatus and manufacturing method using the same {TRIMETHYLOLPROPANE MANUFACTURING DEVICE AND METHOD USING THEREOF}

The present description relates to an apparatus for producing trimethylolpropane and a method using the same, and more particularly, moisture in the aldol reaction product including DMB (2,2-dimethylolbutanal) generated after the aldol reaction, formaldehyde, and By removing methanol and reusing the removed formaldehyde in the aldol reaction, cost reduction and environmental pollution are prevented, and the extraction process of the existing process and the organic solvent purification process are not required, simplifying the process and reducing energy consumption for the entire process. It relates to an apparatus for producing trimethylolpropane and a production method using the same.

TMP (trimethylolpropane) is a white crystalline substance 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 plasticizers. Therefore, research to produce trimethylolpropane, an industrially important raw material, in an economical manner is continuously being conducted.

The industrial production of TMP uses n-butyraldehyde and formaldehyde as starting materials. In general, 2,2-dimethylolbutanal is first formed through the intermediate 2-methylolbutanal through a base-catalyzed reaction, and in the final step, trimethylolpropane is released simultaneously with the release of calcium formate in the presence of calcium hydroxide. Is formed. However, the process is carried out as a one-step process, which has the disadvantage of not being able to individually optimize the individual reaction steps, i.e. the formation of 2,2-dimethylolbutanal and its conversion to trimethylolpropane. This is problematic in that the yield based on the formation of undesirable by-products and the n-butyraldehyde used is not satisfactory.

To avoid this drawback, a two-step process was developed in which 2,2-dimethylolbutanal is prepared from n-butyraldehyde and formaldehyde by condensation reaction in the first step and then hydrogenated in the second step.

DE-A 25 07 461 is obtained for example from n-butyraldehyde and formaldehyde in the presence of a catalytic amount of tert-trialkylamine in which 2,2-dimethylolbutanal contains at least one branched alkyl radical Next, a two-step process of hydrogenation is described. A yield of about 75% trimethylolpropane can be obtained based on the n-butyraldehyde used, but this is not a satisfactory level.

According to DE-A 196 53 093, in the first step, the production of 2,2-dimethylolbutanal is by condensation reaction of n-butyraldehyde and formaldehyde in the presence of a catalytic amount of tert-amine in three stages. If carried out and further reacted by recycling the unreacted starting materials and formed by-products, the yield of trimethylolpropane based on the n-butyraldehyde and formaldehyde used can be significantly increased. In the second step, the condensation product (2,2-dimethylolbutanal) obtained in this way is hydrogenated with trimethylolpropane.

EP-A 860 419 is also used in the production of 2,2-dimethylolbutanal from n-butyraldehyde and formaldehyde, that is, the first step of trimethylolpropane production, the actual reaction takes place in the first stage, and in the second stage. It is proposed to carry out a plurality of stages in which 2-ethylacrolein formed as a by-product reacts with additional formaldehyde. 2,2-dimethylolbutanal prepared in this way can be hydrogenated in a second step to obtain trimethylolpropane.

Although the above process of preparing trimethylolpropane in two steps, namely the production step of 2,2-dimethylolbutanal and then the production step of trimethylolpropane, the two steps can be individually optimized, thus obtaining an excellent yield. Among the above processes, a lot of energy is consumed due to the process of removing water, and thus price competitiveness is deteriorated.

In addition, in the conventional process, the DMB produced by the aldol reaction is extracted with a solvent and then concentrated to obtain trimethylolpropane (TMP) through a hydrogenation reaction (hereinafter referred to as'hydrogenation reaction'), followed by distillation and purification. Therefore, there is a problem that energy consumption is high for water removal, a large amount of solvent is required as an extracting agent, an additional device for separating/recovering formaldehyde as a starting material is required, and yet there is not little loss of DMB as a product.

In order to solve the problems of the prior art as described above, the present substrate removes moisture, formaldehyde and methanol in the aldol reaction product including DMB (2,2-dimethylolbutanal) generated after the aldol reaction, and removes formaldehyde Reusable for aldol reaction to reduce cost and prevent environmental pollution, simplify the process by not requiring the extraction process and organic solvent purification process of the existing process, and to provide a low energy consumption process, and a manufacturing method using the same It aims to provide.

All of the above and other objects of the present description can be achieved by the present description described below.

In order to achieve the above object, the present disclosure includes: a) an aldol reactor for generating DMB by aldol-reacting n-butyraldehyde and formaldehyde in the presence of an amine compound as a catalyst; b) a DMB purifier for removing some or all of moisture, formaldehyde, and methanol from the aldol reaction product including the DMB; c) a hydrogenation reactor for generating TMP (trimethylolpropane) by hydrogenating DMB from which moisture, formaldehyde and methanol have been removed; And d) a purification device for purifying the TMP.

In addition, the present description relates to 1) an aldol reaction of n-butyraldehyde and formaldehyde in the presence of an amine compound as a catalyst to produce DMB (2,2-dimethylolbutanal); 2) removing some or all of moisture, formaldehyde, and methanol from the aldol reaction product including DMB of step 1); 3) generating TMP (trimethylolpropane) by hydrogenating DMB from which moisture, formaldehyde and methanol have been removed in step 2); And 4) removing low boiling point impurities and high boiling point impurities from the TMP generated in step 3).

According to the present description, the extraction efficiency of DMB is maximized by pre-removing moisture, formaldehyde and methanol in the aldol reaction product including DMB after the aldol reaction, and an organic solvent is not required for DMB extraction, and an additional formaldehyde separation and recovery process is performed. Since it is not necessary, the process is simplified and the energy consumption for the entire process is reduced.

FIG. 1 is a trimethylolpropane for producing DMB by conventional aldol reaction of n-butyraldehyde and formaldehyde, and then extracting and concentrating it with an organic solvent, preparing TMP through hydrogenation, and purifying TMP by a distillation column. It is an apparatus diagram schematically showing a manufacturing apparatus.
FIG. 2 shows an aldol reaction product containing DMB of n-butyraldehyde and formaldehyde according to the present disclosure, after removing some or all of moisture, formaldehyde, and methanol using a DMB purifier, and preparing it as TMP by a hydrogenation reaction. And, it is an apparatus diagram schematically showing an apparatus for producing trimethylolpropane for purifying TMP by a purification column.
3 is a schematic diagram illustrating a conventional TMP manufacturing process.
4 is a process chart briefly showing the manufacturing process of the TMP according to the present description.

Hereinafter, an apparatus for producing trimethylolpropane according to the present invention will be described in detail.

The apparatus for producing trimethylolpropane of the present disclosure comprises: a) an aldol reactor for generating DMB (2,2-dimethylolbutanal) by aldol-reacting n-butyraldehyde and formaldehyde in the presence of an amine compound as a catalyst; b) a DMB purifier for removing some or all of moisture, formaldehyde, and methanol from the aldol reaction product including the DMB; c) a hydrogenation reactor for producing trimethylolpropane (TMP) by hydrogenating DMB from which moisture, formaldehyde and methanol have been removed; And d) a purification device for purifying the TMP.

In the a) aldol reactor, the amine compound may be, for example, trimethylamine, triethylamine, or a mixture thereof, and in this case, the formation of by-products is suppressed and DMB generation efficiency is excellent.

In the a) aldol reactor, the amine compound may be used in an amount of 0.01 to 0.5 moles, 0.02 to 0.1 moles, or 0.03 to 0.08 moles per 1 mole of n-butyraldehyde, and within this range, DMB generation efficiency is excellent and by-products are small. As long as it is created, it works.

In the a) aldol reactor, the formaldehyde may be in the form of an aqueous solution containing 1 to 50% by weight, 20 to 40% by weight, or 30 to 37% by weight of formaldehyde, and in this case, the DMB generation efficiency is It has an excellent effect.

In the a) aldol reactor, n-butyraldehyde and formaldehyde may be, for example, in a molar ratio of 1:2 to 1:19, 1:2 to 1:5, or 1:2 to 1:3, and within this range There is an effect of excellent DMB generation efficiency.

The a) aldol reaction in the aldol reactor as an example, the a) aldol reaction in the aldol reactor as an example, the reaction temperature 5 to 100 ℃, 15 to 80 ℃, or 20 to 60 ℃; And the reaction time can be carried out for 20 minutes to 12 hours, 1 to 6 hours, or 2 to 4 hours, within this range there is an effect of excellent reaction efficiency.

In the b) DMB purifier, for example, a transfer pipe for transferring the removed moisture and formaldehyde to the aldol reactor may be combined, and in this case, the previously removed moisture and formaldehyde may be directly recovered to the aldol reactor, thereby simplifying the process and It has an excellent economic effect.

The removed moisture and formaldehyde may be, for example, an aqueous solution containing 1 to 37% by weight, or 10 to 30% by weight of formaldehyde.

The b) DMB purifier can remove 90% by weight or more, 90 to 100% by weight, or 95 to 100% by weight from 100% by weight of moisture from the aldol reactant, for example, and within this range, the extractor and organic solvent at the rear end are purified. Since the tower is not required, the process is simplified, and the amount of heat required to remove moisture at the rear stage is reduced, thereby reducing energy consumption.

In addition, the b) DMB purifier may remove 95% by weight or more, 95 to 100% by weight, or 97 to 100% by weight of formaldehyde from 100% by weight of the aldol reaction product including DMB, for example, and within this range The formaldehyde removed since the extractor and the organic solvent purification tower at the rear stage are not required, and thus the removed formaldehyde can be directly transferred to the aldol reactor and reused, so that the process simplification and economical efficiency are excellent.

In addition, the b) DMB purifier can remove 95% by weight or more, 95 to 100% by weight, or 97 to 100% by weight in 100% by weight of methanol from the aldol reaction product including DMB, for example, within this range There is no need for an extractor and an organic solvent purification tower at the rear stage, which simplifies the process and reduces energy consumption.

The b) DMB purifier may include a distillation column as an example, and in this case, the effect of removing moisture, formaldehyde, and methanol is excellent.

The distillation column is, for example, a top temperature of 65 to 90 ℃, 70 to 90 ℃, or 75 to 85 ℃; A bottom temperature of 120 to 150°C, 125 to 145°C, or 130 to 140°C; Pressure 250-550 mmHg, 300-500 mmHg, or 350-450 mmHg; It can be operated under conditions, and within this range, the removal efficiency of moisture, formaldehyde, and methanol is excellent, and the loss of major substances such as DMB and TMP is reduced.

In the c) hydrogenation reactor, hydrogen is added to DMB from which moisture, formaldehyde and methanol have been removed in the b) DMB purifier to prepare TMP.

The c) hydrogenation reactor may include, for example, a hydrogenation catalyst, and is not particularly limited in the case of a hydrogenation catalyst capable of hydrogenating aldehyde with alcohol.

In the c) hydrogenation reactor, for example, all of the remaining formaldehyde is converted into methanol and removed from the purifier at the rear stage.

The d) purification apparatus includes, for example, i) a low boiling point purification column for removing low boiling point impurities from the TMP generated by the hydrogenation reaction, and ii) a high boiling point purification column for removing high boiling point impurities from the TMP from which the low boiling point impurities have been removed. In this case, high purity TMP can be obtained.

In the i) low boiling point refining column, low boiling point impurities are discharged through the upper pipe, for example, and the remaining substances including TMP are transferred to ii) the high boiling point refining column through the lower pipe.

For example, in the ii) high boiling point removal column, high boiling point impurities are discharged through a lower pipe, and TMP is obtained through an upper pipe.

In the d) purification apparatus, the low boiling point impurity refers to a material having a boiling point lower than that of TMP, and may be water, methanol, or an amine compound.

The high boiling point impurity is a material having a higher boiling point than TMP, and may be, for example, a by-product of the aldol reaction.

The i) low boiling point refined column is, for example, pressure 35 to 65 mmHg, 40 to 60 mmHg, or 45 to 55 mmHg; A top temperature of 125 to 155°C, 130 to 150°C, or 135 to 145°C; And a bottom temperature of 210 to 240°C, 215 to 235°C, or 220 to 230°C; It can be operated under conditions, and within this range, the purification effect of low boiling point impurities is excellent.

The ii) high boiling point refined column is, for example, a pressure of 10 to 30 mmHg, 15 to 25 mmHg, or 18 to 23 mmHg; A top temperature of 180 to 210°C, 190 to 200°C, or 190 to 195°C; And a bottom temperature of 230 to 260°C, 235 to 255°C, or 240 to 250°C; It can be operated under conditions, and within this range, the purification effect of high boiling point impurities is excellent.

In addition, the method for preparing trimethylolpropane of the present disclosure includes 1) reacting n-butyraldehyde and formaldehyde with an aldol in the presence of an amine compound as a catalyst to produce DMB (2,2-dimethylolbutanal); 2) removing some or all of moisture, formaldehyde, and methanol from the aldol reaction product including DMB of step 1); 3) generating TMP by hydrogenating DMB from which moisture, formaldehyde and methanol have been removed in step 2); And 4) removing low boiling point impurities and high boiling point impurities from the TMP obtained in step 3).

The amine compound in step 1) may be, for example, trimethylamine, triethylamine, or a mixture thereof, and in this case, DMB generation efficiency is excellent.

The moisture and formaldehyde removed in step 2) may be transferred to step 1) and reused, for example, and in this case, there is an effect that an additional formaldehyde separation and recovery device is not required.

In the above step 2), the aldol reaction product including DMB may remove, for example, 90% by weight or more, 90 to 100% by weight, or 95 to 100% by weight of the total moisture 100% by weight, and within this range, the rear end Since the extractor and the organic solvent purification tower are not required, the process is simplified, and the amount of heat required to remove moisture at the rear stage is reduced, thereby reducing energy consumption.

In the above step 2), the aldol reaction product including DMB may remove formaldehyde at least 95% by weight, 95 to 100% by weight, or 97 to 100% by weight of the total formaldehyde 100% by weight, within this range. There is no need for an extractor and an organic solvent purification tower at the rear stage, and can be directly recovered to the Aldol reactor, thereby simplifying the process and having excellent economic efficiency.

The aldol reaction product including DMB in the step 2) may remove 95% by weight or more, 95 to 100% by weight, or 97 to 100% by weight of methanol, for example, of 100% by weight of total methanol, and the rear end within this range Since the extractor and the organic solvent purification tower are not required, the process is simplified and energy consumption is reduced.

In the step 2), a distillation column may be used as an example, and in this case, the effect of removing moisture, formaldehyde, and methanol is excellent.

The distillation column may be, for example, a top temperature of 65 to 90°C, 70 to 90°C, or 75 to 85°C; A bottom temperature of 120 to 150°C, 125 to 145°C, or 130 to 140°C; And pressure 250 to 550 mmHg, 300 to 500 mmHg, or 350 to 450 mmHg; and within this range, moisture, formaldehyde, and methanol are efficiently removed while reducing product loss.

In step 3), in the step of hydrogenating DMB from which some or all of moisture, formaldehyde and methanol are removed in step 2) to generate trimethylolpropane, residual formaldehyde is converted to methanol, which is step 4). It can be separated into low-boiling impurities.

The removal of the low-boiling point impurities in the step 4) may be performed at a pressure of 35 to 65 mmHg, 40 to 60 mmHg, or 45 to 55 mmHg through a low boiling point purification column, for example; A top temperature of 125 to 155°C, 130 to 150°C, or 135 to 145°C; And a bottom temperature of 210 to 240°C, 215 to 235°C, or 220 to 230°C; It can be carried out under conditions, and within this range, the purification effect of low boiling point impurities is excellent.

The removal of the high boiling point impurities in the step 4) may be performed at a pressure of 10 to 30 mmHg, 15 to 25 mmHg, or 18 to 23 mmHg through a high boiling point purification column, for example; A top temperature of 180 to 210°C, 190 to 200°C, or 190 to 195°C; And a bottom temperature of 230 to 260°C, 235 to 255°C, or 240 to 250°C; It can be carried out under conditions, and within this range, the purification effect of high boiling point impurities is excellent.

For example, first, a low boiling point impurity is removed from a crude TMP product through a low boiling point purification column, and then a high boiling point impurity is removed again through a high boiling point purification column to obtain purified TMP.

For example, first, after removing high boiling point impurities through a high boiling point purification column, then, after removing low boiling point impurities through a low boiling point purification column, purified TMP is obtained.

The low boiling point impurity includes water, methanol, or an amine compound, for example, and the high boiling point impurity is a material having a boiling point higher than that of TMP, and may include, for example, a by-product of aldol reaction.

Hereinafter, a preferred embodiment is presented to aid in the understanding of the present invention, but it is obvious to those skilled in the art that various changes and modifications are possible within the scope of the present invention and the scope of the technical idea, but the following examples are only illustrative of the present invention, It is natural that such modifications and modifications fall within the appended claims.

[Example]

Example One

In the device installed as shown in FIG. 2, n-butyraldehyde (B) and formaldehyde (F) are in a molar ratio (B:F) of 1:2, and triethylamine (TEA) as a catalyst is 1 mol of n-butyraldehyde. Add 0.03 mol of sugar for 2 hours at a temperature of 50℃ During Aldol reaction was carried out in the Aldol reactor. The aldol reaction product was removed from a DMB purifier with 98% by weight of moisture, 99% by weight of formaldehyde, and 99% by weight of methanol under pressure of 400mmHg, a top temperature of 79°C, and a bottom temperature of 137°C under the conditions of Table 1 below . The DMB from which the moisture, formaldehyde and methanol have been removed is transferred to a hydrogenation reactor to prepare crude TMP by hydrogenation, and then passed through a low-boiling-point purification column and a high-boiling-point purification column under the conditions shown in Table 1 below to finally purified TMP Was obtained.

At this time, the TMP obtained had a TMP recovery rate of 97.5% and a purity of 99.99% or more with respect to the added n-butyraldehyde.

The total energy consumption according to the above process was 4.51 Gcal/hr.

Comparative example One

With the device installed as shown in FIG. 1, n-butyraldehyde (B) and formaldehyde (F) are in a molar ratio (B:F) of 1:2, and TEA as a catalyst is a ratio of 0.03 moles per mole of n-butyraldehyde. Into the Aldol reaction was carried out in an Aldol reactor at a temperature of 50° C. for 2 hours. DMB was extracted from the aldol reactor product in an extractor using 2-ethylhexanol as an extractant under the conditions of Table 1 below, and then crude TMP generated after the hydrogenation reaction was removed from low boiling point impurities and high boiling point impurities under the conditions of Table 1 below. Then, the organic solvent was purified to obtain a final TMP and an organic solvent, respectively.

The obtained TMP had a TMP recovery rate of 97.5% and a purity of 99.99% or more for the added n-butyraldehyde.

The total energy consumption according to the above process was 4.73 Gcal/hr.

[Test Example]

The TMP recovery rate, TMP purity, and water removal rate prepared in Example 1 and Comparative Example 1 were measured by the following method, and the results are shown in Table 2 below.

How to measure

* TMP recovery rate (%): The ratio of the final TMP product to the amount of TMP produced by the reaction

* TMP purity (%): the ratio of the amount of pure TMP in the final TMP product

* Water removal rate (% by weight): The ratio of the amount of water removed to the amount of water in the aldol reaction product

division Example 1 Comparative Example 1 extraction none Equipment (extractor) Driving pressure X 1,500 mmHg Solvet flow X 3,500 Kg/hr Water removal rate X 47.1% Energy consumption X 0 Gcal/hr DMB tablet Equipment (DMB purification tower) none Driving pressure 400 mmHg X Tower top temperature 79 ℃ X Bottom temperature 137 ℃ X Water removal rate 98.5% X Energy consumption 3.20 Gcal/hr X Low boiling point removal Equipment (low boiling point refining column) Equipment (low boiling point removal tower) Driving pressure 50 mmHg 190 mmHg Tower top temperature 141 ℃ 112 ℃ Bottom temperature 226 ℃ 253 ℃ Energy consumption 0.43 Gcal/hr 2.94 Gcal/hr High boiling point removal Equipment (high boiling point refinery column) Equipment (high boiling point removal tower) Driving pressure 20 mmHg 20 mmHg Tower top temperature 192 ℃ 192 ℃ Bottom temperature 244 ℃ 250 ℃ Energy consumption 0.88 Gcal/hr 0.70 Gcal/hr Organic solvent removal none Equipment (organic solvent removal tower) Driving pressure X 300 mmHg Tower top temperature X 66 ℃ Bottom temperature X 157 ℃ Energy consumption X 1.09 Gcal/hr

division Example 1 Comparative Example 1 TMP recovery rate 97.5% 97.5% TMP purity 99.99% or more 99.99% or more Total energy use 4.51 Gcal/hr 4.73 Gcal/hr

As shown in Table 2, it was confirmed that Example 1 of the present disclosure reduced the total energy consumption by 4.7% from 4.73 Gcal/hr to 4.51 Gcal/hr while maintaining the TMP recovery rate and purity compared to Comparative Example 1, which is the prior art. Could. This is because the amount of water removed from the DMB purification tower of the present disclosure is greater than the amount of water removed from the conventional extractor.

In addition, Comparative Example 1, which is a prior art, requires an extraction step using 2-ethylhexanol as an extracting agent and an organic solvent purification step to remove it, so the process is complicated. Since the step is not required, the process has been simplified.

Claims (16)

a) an aldol reactor for producing DMB (2,2-dimethylolbutanal) by reacting an aldol with n-butyraldehyde and formaldehyde in the presence of an amine compound as a catalyst; b) a DMB purifier for removing some or all of moisture, formaldehyde, and methanol from the aldol reaction product including the DMB; c) a hydrogenation reactor for generating TMP (trimethylolpropane) by hydrogenating DMB from which moisture, formaldehyde and methanol have been removed; And d) a purification device for purifying the TMP; including,
B) the DMB purifier includes a distillation column,
The distillation column has a top temperature of 75 to 85°C; Bottom temperature of 130 to 140°C; Pressure 350-450 mmHg; Works under conditions,
The b) DMB purifier removes more than 90% by weight of moisture from 100% by weight of moisture in the aldol reaction product, removes more than 95% by weight from 100% by weight of formaldehyde, and removes more than 95% by weight from 100% by weight of methanol. ,
An apparatus for producing trimethylolpropane, characterized in that it does not include an organic solvent purification tower and an extractor.
The method of claim 1,
The d) purification apparatus comprises i) a low boiling point purification column for removing low boiling point impurities from the TMP, and ii) a high boiling point purification column for removing high boiling point impurities from the TMP.
The method of claim 1,
In the above a) aldol reactor, the amine compound is trimethylolpropane, trimethylamine, triethylamine, or a mixture thereof.
delete The method of claim 1,
The b) DMB purifier device for producing trimethylolpropane, characterized in that a transfer pipe for transferring the removed formaldehyde to the aldol reactor is coupled.
delete delete 1) Aldol-reacting n-butyraldehyde and formaldehyde in the presence of an amine compound as a catalyst to produce DMB (2,2-dimethylolbutanal);
2) DMB purification step of removing some or all of moisture, formaldehyde, and methanol from the aldol reaction product including DMB of step 1);
3) generating TMP (trimethylolpropane) by hydrogenating DMB from which moisture, formaldehyde and methanol have been removed in step 2); And
4) removing low boiling point impurities and high boiling point impurities from the TMP generated in step 3); including,
The step 2) removes more than 90% by weight from 100% by weight of moisture in the aldol reaction product containing DMB, removes more than 95% by weight from 100% by weight of formaldehyde, and removes more than 95% by weight from 100% by weight of methanol and,
The step 2) uses a distillation column,
The distillation column is carried out under conditions of a top temperature of 75 to 85°C, a bottom temperature of 130 to 140°C, and a pressure of 350 to 450 mmHg,
A method for producing trimethylolpropane, characterized in that it does not include extracting the aldol reaction product with an organic solvent and purifying the organic solvent.
The method of claim 8,
The amine compound of step 1) is trimethylolpropane, characterized in that trimethylamine, triethylamine, or a mixture thereof.
The method of claim 8,
The method for producing trimethylolpropane, characterized in that the moisture and formaldehyde removed in step 2) are transferred to step 1) and reused.
delete delete delete The method of claim 8,
The removal of the low-boiling point impurities in step 4) is carried out under conditions of a pressure of 35 to 60 mmHg, a top temperature of 125 to 155°C, and a bottom temperature of 210 to 240°C.
The method of claim 8,
The removal of the high boiling point impurities in step 4) is carried out under the conditions of a pressure of 10 to 30 mmHg, a top temperature of 180 to 210°C, and a bottom temperature of 230 to 260°C.
delete

Images