KR101063778B1

KR101063778B1 - Method of manufacturing glycerol carbonate

Info

Publication number: KR101063778B1
Application number: KR1020100128836A
Authority: KR
Inventors: 곽진식; 박기돈; 윤준우; 하태호
Original assignee: 주식회사 엠에너지
Priority date: 2010-12-16
Filing date: 2010-12-16
Publication date: 2011-09-08

Abstract

The present invention relates to a method for producing glycerol carbonate, potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), methoxide potassium (CH ₃ OK), sodium hydroxide (NaOH), sodium methoxide (CH ₃ ONa) Glycerine and dimethyl carbonate (DMC) are added to the reaction tank at a molar ratio of 1: 1.5 to 1: 5, and the temperature of the reactor is maintained at 110 ° C to 180 ° C. Reacting for at least 60 minutes to produce glycerol carbonate by reacting the glycerin with the dimethyl carbonate; A recovery step of recovering the methanol generated in the first reaction step; In the first reaction step together with at least one catalyst of potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), potassium methoxide (CH ₃ OK), sodium hydroxide (NaOH), sodium methoxide (CH ₃ ONa) 0.5 times or more dimethyl carbonate (DMC) of the glycerine was added to the reactor, the temperature of the reactor is maintained at 70 ℃ to 180 ℃, the reaction of the glycerine and the dimethyl carbonate compared to the first reaction step A secondary reaction step of producing high purity glycerol carbonate; It provides a method capable of producing a high yield of glycerol carbonate of more than 90% in a short 2 to 3 hours compared to the prior art.

Description

Method for producing glycerol carbonate {METHOD OF MANUFACTURING GLYCEROL CARBONATE}

The present invention relates to a method for producing glycerol carbonate, and more particularly to a method for producing a high yield of glycerol carbonate in a short time compared to the conventional.

With the recent surge in oil prices and the necessity of environmental protection, research on environmentally friendly energy is vigorous. As part of this, research on biodiesel is expanding, and biodiesel production and usage are gradually increasing.

As biodiesel production increases, studies on the utilization of glycerol produced as a by-product in the biodiesel manufacturing process are being conducted. Glycerol may be utilized as a glycerol carbonate that can be used for various applications such as surfactants, various coating agents, pharmaceuticals, cosmetics, and paint removers, and thus, glycerol has been sought to prepare glycerol carbonate at a lower cost.

Korean Unexamined Patent Publication No. 2009-27297 relates to a method for preparing glycerol carbonate, proposed by Jeong Kwang-seop et al., Wherein 0.8 wt% to 1.2 wt% of a lipase, a biocatalyst, is added at 40 ° C. to 70 ° C. under normal pressure, and a reaction solvent is used. Phosphorus (Tetrahydrofuran), AcCN (Acetonitrile) and t-BuOH (t-Butanol) are mixed to react glycerol with dimethyl carbonate (Demethyl Carbonate) for 5 to 24 hours to obtain a 69.7% conversion. . However, the manufacturing method of the glycerol carbonate as described above has a problem that it takes a long time to the reaction and the yield is lower than 70%, the production cost is increased and can not obtain a good quality glycerol carbonate.

On the other hand, Japanese Patent Publication No. 35245242 is a "method for producing glycerol carbonate" filed and filed by KAO, Japan, according to this, glycerol carbonate by adding 0.1 ~ 10wt% of alkaline earth metal such as zinc oxide, magnesium oxide as a catalyst In the manufacturing technology, specifically, 92 g (1 mole) of glycerin and 130 g of 2-ethoxyethyl ether are mixed and stirred at 120 ° C., followed by 60 g (1 mole) of urea and 7 g of magnesium sulfate, which is 13.3 kPa to 101 kPa. It reacts for 24 hours in a pressurized state, and obtains 58% of glycerol carbonate and diglycerol. However, the conventional technology not only takes a long time for the reaction, but also has a low yield of 60% or less, which leads to an increase in manufacturing cost and a limitation in that glycerol carbonate of good quality cannot be obtained.

In addition, Japanese Patent Publication No. 10195067 is a "Production of 4-hydroxymethyl-1,3-dioxolane compound" filed and filed by LION of Japan, and accordingly, 150 ° C as a raw material containing glycerin containing a large amount of water. A method of obtaining glycerol carbonate by mixing with a solvent having the following boiling point and then adding an acid catalyst followed by heating and evaporating with water is disclosed. However, there is a problem in that a large cost is required to remove a large amount of water generated when condensation reaction under an acid catalyst by mixing glycerin and a carbonyl compound.
Meanwhile,

Thus, there is a very high need for the production of glycerol carbonate in high yields inexpensively and in a relatively short time.

The present invention is to provide a method for producing a high yield of glycerol carbonate in a short time compared to the conventional, in order to solve the above conventional problems.
Above all, glycerol carbonate according to the invention

That is, the present invention aims to stably produce 90% or more yield of glycerol carbonate through a reaction of approximately 2 to 3 hours.

The present invention, any one of potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), potassium methoxide (CH ₃ OK), sodium hydroxide (NaOH), sodium methoxide (CH ₃ ONa) With one or more base catalysts, glycerin and dimethyl carbonate (DMC) are charged to a reactor in a molar ratio of 1: 1.5 to 1: 5 and reacted while maintaining the temperature of the reactor at 70 ° C to 180 ° C, A first reaction step of producing glycerin carbonate by reaction of the glycerin with the dimethyl carbonate; A recovery step of recovering methanol generated in the first reaction step after the first reaction step is performed for 60 minutes or more; In the first reaction step together with at least one catalyst of potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), potassium methoxide (CH ₃ OK), sodium hydroxide (NaOH), sodium methoxide (CH ₃ ONa) 0.5 times or more dimethyl carbonate (DMC) of the glycerine was added to the reactor, the temperature of the reactor is maintained at 70 ℃ to 180 ℃, the reaction of the glycerine and the dimethyl carbonate compared to the first reaction step A secondary reaction step producing high purity glycerin carbonate; It provides a method for producing glycerin carbonate comprising the.

This is to obtain a higher reaction rate by removing methanol generated during the reaction of glycerin and dimethyl carbonate to produce glycerol carbonate. Through this, even if the reaction of glycerin and dimethyl carbonate for 7 hours was obtained a low yield of 40% to 50%, but by recovering the methanol intermediate product of glycerin and dimethyl carbonate to improve the glycerol carbonate to a yield of up to 70% Can be.

The recovery step is preferably performed in a state where the first reaction step proceeds sufficiently. Therefore, the recovery step may be performed in a state in which the first reaction step is 20 minutes to 60 minutes, thereby effectively improving the reaction rate according to the first recovery step. At this time, since the reaction rate increases to the maximum in the state where the primary recovery step has been operated for about 60 minutes, it is preferable to perform 60 minutes or more.

Above all, in the present invention, after the first recovery step, a second reaction in which dimethyl carbonate (DMC) and a base catalyst are further added to the reaction tank and reacted while maintaining the temperature of the reaction tank at 70 ° C to 180 ° C. Steps; It is characterized in that it further comprises. At this time, a secondary recovery process may be performed to remove methanol during the secondary reaction step. Through this, glycerol carbonate can be obtained in high yield of more than 90%.

Here, the first reaction step and the second reaction step may be performed in a short time of 100 minutes to 180 minutes, thereby obtaining glycerol carbonate in a high yield. That is, after 20 minutes to 60 minutes have elapsed from the first reaction step, the first recovery step is performed, and the secondary reaction is then carried out for 20 minutes to 60 minutes in a short time with a high yield of 90% or more of glycerol carbonate. It becomes possible to manufacture.

Similarly, after 20 to 60 minutes have elapsed from the first reaction step, the first recovery step is carried out for a short time, such as 15 minutes, and then the second reaction step is carried out with 20 to 60 minutes of the secondary reaction. By going through the recovery step again during the process, glycerol carbonate may be prepared in a short time with a high yield of 90% or more.

On the other hand, the glycerin may be a substance consisting of only glycerin, but includes a composition containing glycerin.

In addition, in the first reaction step, the base catalyst is administered by 0.01 wt% to 3.0 wt%, preferably about 0.1 wt%, and even in the second reaction, the base catalyst is 0.01 wt% to 3.0 wt%, preferably Preferably by about 0.1 wt%.

The base catalyst may be various base catalysts such as potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), potassium methoxide (CH ₃ OK), sodium hydroxide (NaOH), sodium methoxide (CH ₃ ONa). . The reaction rate for these base catalysts shows excellent properties as shown in FIG. Of these base catalysts, potassium hydroxide (KOH) achieved the highest reaction rate. Therefore, potassium hydroxide or the like may be added to the first reaction and the second reaction as a base catalyst.

On the other hand, the present invention includes a secondary recovery step of recovering the methanol produced in the secondary reaction step during the secondary reaction step; A third reaction step of adding dimethyl carbonate (DMC) and a base catalyst to the reactor further, and maintaining the temperature of the reactor at 70 ° C to 180 ° C; In addition, the three-stage reaction can be obtained in higher yield of glycerol carbonate.

As described above, the present invention, after the first reaction for a predetermined time while maintaining the temperature range of 70 ℃ to 180 ℃ by adding glycerine and dimethyl carbonate (DMC), methanol generated in the first reaction step By including the first recovery step to recover during the first reaction step, to obtain the advantageous effect of producing glycerol carbonate in a high yield up to 70%.

In addition, the present invention by adding the dimethyl carbonate (DMC) and the base catalyst after the second recovery step to the secondary reaction, to obtain an advantageous effect of producing a glycerol carbonate with a high yield of 90% or more.

The present invention can be produced for a short time of only 100 minutes to 180 minutes glycerol carbonate in a high yield as described above, there is an advantage to significantly improve the productivity of glycerol carbonate.

1 is a flow chart sequentially showing a manufacturing method of glycerol carbonate according to an embodiment of the present invention
Figure 2 is a scheme of the production mechanism of glycerol carbonate by transesterification under base catalyst
3 is a view schematically showing the configuration of a reflux reaction device of glycerin and dimethyl carbonate
4 is a schematic view of a recovery apparatus for methanol (MeOH);
5 is experimental data showing the reaction rate over time of the recovery step.
Figure 6 is a comparative experimental data of the reaction rate after the recovery step and the reaction rate without the recovery step
7 is a comparative experimental data of the reaction rate according to the amount of catalyst
8 is a comparative experiment data of the reaction rate according to the type of catalyst
9 is experimental data of measuring the yield of glycerol carbonate for each reaction time of Example 1
10 is experimental data obtained by measuring the yield of glycerol carbonate for each reaction time of Example 2. FIG.

Hereinafter, a method of preparing glycerol carbonate according to an embodiment of the present invention with reference to the accompanying drawings. In the following description, well-known functions or constructions are not described in detail to avoid obscuring the subject matter of the present invention.

1 is a flowchart sequentially showing a method for preparing glycerol carbonate according to an embodiment of the present invention.

As shown in the figure, in the method for preparing glycerol carbonate according to one embodiment of the present invention (S100), glycerine and dimethyl carbonate (DMC) are added to a reaction tank together with a base catalyst, and the temperature of the reaction tank is 70 ℃ to After the first reaction step (S110) to react while maintaining at 180 ℃, the recovery step (S120) and the recovery step (S120) to recover the methanol generated in the first reaction step (S110) during the first reaction step Dimethyl carbonate (DMC) and the base catalyst is further added to the reaction tank and consists of a secondary reaction step (S130) to react while maintaining the temperature of the reactor at 70 ℃ to 180 ℃.

Glycerol carbonate and methanol are produced according to the reaction shown in FIG. 2 by the reaction of glycerine and dimethyl carbonate (DMC) under potassium hydroxide (KOH) which is a base catalyst by the first reaction step (S110). At this time, glycerin and dimethyl carbonate are introduced at a molar ratio of dimethyl carbonate higher than that of glycerin in a molar ratio of 1: 1.5 to 1: 5. The base catalyst is one or more of a base catalyst of potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), potassium methoxide (CH ₃ OK), sodium hydroxide (NaOH) and sodium methoxide (CH ₃ ONa). , 0.1wt%.

Here, the pressure may not be controlled separately during the first reaction step (S110), and the pressure is measured to be about 4 bar to 9 bar by the reaction.

And, the first reaction step (S110) may be made by the reaction by the reflux operation shown in FIG. That is, during the reaction of glycerin (GOH) and dimethyl carbonate (DMC) contained in the reaction tank 10, it does not escape to the outside, and vaporizes and moves to a spiral tube 20 extending upwardly inclined from the reaction tank 10 and then cooled. After the liquefaction, the liquid flows down in the direction indicated by reference numeral 20d and is collected again in the reactor 10.

Here, the first reaction step (S110) is made at a temperature higher than 70 ℃, at a temperature lower than 70 ℃ the reaction rate of glycerin and dimethyl carbonate is lowered, causing a problem that the yield is lowered, at a temperature higher than 180 ℃ This is because a reverse reaction in which the amount of the product is reduced causes a problem of discoloration of the basic catalyst potassium hydroxide (KOH) by high temperature.

When the first reaction step (S110) is performed for 20 to 60 minutes to sufficiently produce the product, a recovery step (S120) is performed to remove methanol (MeOH), which is an intermediate product, by using the recovery device illustrated in FIG. 4. . That is, methanol (MeOH) and dimethyl carbonate (DMC) vaporized by low melting point during the reaction of glycerin (GOH) and dimethyl carbonate (DMC) contained in the reactor 10 are vaporized and moved through the spiral tube 30 and then cooled. In the liquefied state it flows down in the direction indicated by the reference numeral 30d and collects in the recovery container 40 located separately from the reaction tank 10. Accordingly, the amount of dimethyl carbonate (DMC) and the catalyst contained in the reactor 10 is reduced as the recovery step (S120) proceeds.

The recovery step of removing methanol (MeOH) (S120) takes place after approximately 60 minutes, at which point the reaction of glycerin and dimethyl carbonate (S110) reaches equilibrium. As shown in FIG. 5, since the reaction rate increases to the maximum when the recovery reaction operation is one hour as shown in FIG. 5, the recovery step S120 is preferably maintained at 60 minutes or more at which the reaction rate is maximized. In terms of shortening the reaction time, the recovery step S120 is effective for approximately 60 minutes. However, if the recovery step (S120) is carried out for 15 minutes or more in order to shorten the reaction time, it is possible to improve the production rate compared to the reaction time.

For reference, as shown in FIG. 6, the experimental data of the reaction rate without performing the recovery reaction can confirm that the production rate of glycerol carbonate is lower than that when the recovery reaction is performed even if the reaction is performed for a long time. 5 and 6 are experimental data for analyzing the effects of the recovery reaction. After performing the primary reaction for 3 hours to perform the primary reaction sufficiently, the experimental data for the recovery reaction was performed for 4 hours. It is shown. Glycerol carbonate can be obtained in a yield of 80% or more through the recovery step (S120).

When the recovery step of removing methanol (MeOH) (S120) is completed, the second reaction step (S130) by adding dimethyl carbonate (DMC) and potassium hydroxide (KOH) as a base catalyst to the intermediate reactant from which methanol (MeOH) is removed, respectively. ) For 20 to 60 minutes. In this case, a recovery process of removing methanol (MeOH) may also be simultaneously performed during the secondary reaction step (S130). And, the temperature condition of the second reaction step (S130) is maintained within the same range as the first reaction step (S110). By carrying out the second reaction step (S130), the resulting glycerol carbonate is obtained in high yield of 90% or more.

On the other hand, after the second reaction step (S130) through a second recovery step of removing methanol (MeOH) again, dimethyl carbonate (DMC) and the base catalyst may be further added to the third reaction step. As a result, the yield of glycerol carbonate is increased, but since the high yield of glycerol carbonate of 94% can be obtained within approximately 180 minutes by the second reaction step (S130), only when the yield of 95% or more is desired The reaction step is good to go through.

In addition, the amount of the base catalyst added in order to accelerate the reaction rate of glycerol carbonate is as shown in FIG. 7, where the reaction rate when 0.1 wt% is added is 1.0 wt%, and there is no big tie. Since it is necessary to remove the catalyst for high purity purification in the future, it is effective to add about 0.05wt% to 0.3wt% without using 1.0wt%.

Example 1

After mixing 2 mol of glycerin (GOH), 2 mol of dimethyl carbonate (DMC), and 0.1 wt% of potassium hydroxide as a catalyst, the first reaction was carried out by reflux operation at 170 ° C. for 60 minutes, and then the produced methanol (MeOH) was recovered for 15 minutes. After the first recovery step by operation, 1 mol of dimethyl carbonate (DMC) and 0.1 wt% potassium hydroxide were added to the intermediate reaction product from which methanol (MeOH) was removed, followed by a secondary reaction for 30 minutes, and then methanol ( The secondary reaction was continued while undergoing a secondary recovery step of recovering MeOH) for 60 minutes.

As a result, glycerol carbonate having a yield of 45% was obtained at the time of the first reaction, but after the first recovery step, glycerol carbonate having a yield of 71% was obtained, and the second recovery step and the second reaction were obtained. After the glycerol carbonate having a high yield of 94% was obtained in a short time of 165 minutes (see Fig. 9).

At this time, the analysis of the final product glycerol carbonate was used for Gas Chromatograph (Gas Chromatograph). DB-5ms (5% -Diphenyl-95% -Dimethlysiloxane copolymer, 15m X 0.32m X 1㎛) column was detected using a flame ionization detector, TMS (HMDS, TMCS, Pyridine was mixed with a reagent, and a hydroxyl group and a silane group were substituted to make an analyte in a nonpolar column.

Example 2

After mixing 1 mol of glycerin (GOH), 1.5 mol of dimethyl carbonate (DMC) and 0.2 wt% of potassium hydroxide as a catalyst, the first reaction was carried out by reflux operation at 165 ° C. for 40 minutes, and the produced methanol (MeOH) was recovered for 20 minutes. After the first recovery step by operation, while recovering methanol (MeOH), 0.5 mol of dimethyl carbonate (DMC) and 0.1 wt% of potassium hydroxide were added to the intermediate reactant from which methanol (MeOH) was removed, followed by a secondary reaction for 60 minutes. Was carried out.

As a result, glycerol carbonate having a high yield of 90% to 93% was obtained in a short time of 130 minutes (see Fig. 9).

Example 3

1 mole of glycerin (GOH), 1.5 mole of dimethyl carbonate (DMC), and 1.0 wt% of potassium bicarbonate (KHCO ₃ ) as a catalyst were mixed and subjected to a primary reaction at reflux operation at 155 ° C. for 40 minutes, and then produced methanol (MeOH). After 20 minutes of recovery operation, the first recovery step was carried out, while methanol (MeOH) was recovered, 0.5 mol of dimethyl carbonate (DMC) and 0.5 wt% potassium bicarbonate were added to the intermediate reaction product from which methanol (MeOH) was removed. Second reaction was carried out. As a result, glycerol carbonate having a yield of 90.79% was obtained in a short time of 120 minutes.

Example 4

1 mole of glycerin (GOH), 1.5 mole of dimethyl carbonate (DMC), and 0.5 wt% of sodium hydroxide (NaOH) as a catalyst were mixed and subjected to a primary reaction at reflux operation at 160 ° C. for 40 minutes. 20 minutes recovery operation, the first recovery step, and while recovering methanol (MeOH), 0.5 mol of dimethyl carbonate (DMC) and 0.5wt% sodium hydroxide were added to the intermediate reaction product from which methanol (MeOH) was removed. Differential reaction was carried out. As a result, glycerol carbonate having a yield of 91.49% was obtained in a short time of 120 minutes.

Example 5

1 mol of glycerin (GOH), 1.5 mol of dimethyl carbonate (DMC), and 0.5 wt% of sodium bicarbonate (NaHCO ₃ ) as a catalyst were mixed and subjected to a primary reaction at reflux operation at 120 ° C. for 40 minutes, and then produced methanol (MeOH). 20 minutes recovery operation, the first recovery step, and while recovering methanol (MeOH), 0.5 mol of dimethyl carbonate (DMC) and 0.5 wt% of sodium bicarbonate were added to the intermediate reaction product from which methanol (MeOH) was removed for 60 minutes. Second reaction was performed. As a result, glycerol carbonate having a yield of 87.95% was obtained.

Example 6

1 mole of glycerin (GOH), 1.5 mole of dimethyl carbonate (DMC) and 0.2 wt% of potassium hydroxide as a catalyst were mixed and subjected to a primary reaction at reflux operation at 165 ° C for 40 minutes, followed by a primary reaction at reflux operation for 60 minutes. Thereafter, the produced methanol (MeOH) is subjected to a first recovery step by a 15-minute recovery operation, and 1 mol of dimethyl carbonate (DMC) and 0.1 wt% of potassium hydroxide are additionally added to the intermediate reaction product from which methanol (MeOH) is removed. After performing the secondary reaction for a minute, the secondary recovery step of recovering methanol (MeOH) was carried out again for 15 minutes, and 0.25 mol of dimethyl carbonate (DMC) and 0.025wt% potassium hydroxide were added to the intermediate reactant from which methanol (MeOH) was removed. Was further added to carry out a third reaction for 60 minutes.

As a result, glycerol carbonate having a yield of 92% to 95% was obtained (see FIG. 10). In other words, the degree of improvement of the yield of glycerol carbonate was insignificant in comparison with only the second reaction step even though the third reaction step.

In the above, the preferred embodiments of the present invention have been described by way of example, but the scope of the present invention is not limited to these specific embodiments, and may be appropriately changed within the scope described in the claims.

Claims

Glycerin and dimethyl carbonate (with a base catalyst of at least one of potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), potassium methoxide (CH ₃ OK), sodium hydroxide (NaOH), sodium methoxide (CH ₃ ONa)) DMC) was added to the reactor in a molar ratio of 1: 1.5 to 1: 5, and the reaction was carried out for 60 minutes or more while maintaining the temperature of the reactor at 110 ° C to 180 ° C to react the glycerin with the dimethyl carbonate. A first reaction step of producing glycerol carbonate;
A first recovery step of recovering methanol generated in the first reaction step after the first reaction step;
In the first reaction step together with at least one catalyst of potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), potassium methoxide (CH ₃ OK), sodium hydroxide (NaOH), sodium methoxide (CH ₃ ONa) 0.5 times or more dimethyl carbonate (DMC) of the glycerine was added to the reactor, the temperature of the reactor is maintained at 70 ℃ to 180 ℃, the reaction of the glycerine and the dimethyl carbonate compared to the first reaction step A secondary reaction step of producing high purity glycerol carbonate;
After the secondary reaction step, the secondary recovery step of recovering the methanol generated in the secondary reaction step;
Method for producing glycerol carbonate, characterized in that it comprises.

The method of claim 1,
In the first reaction step together with at least one catalyst of potassium hydroxide (KOH), potassium bicarbonate (KHCO ₃ ), potassium methoxide (CH ₃ OK), sodium hydroxide (NaOH), sodium methoxide (CH ₃ ONa) More than 0.5 times of dimethyl carbonate (DMC) of the glycerine was added to the reactor, the temperature of the reactor was maintained at 70 ℃ to 180 ℃, the reaction of the glycerine and the dimethyl carbonate compared to the second reaction step A tertiary reaction step of producing high purity glycerol carbonate;
Recovering the methanol produced in the third reaction step;
Method for producing glycerol carbonate, characterized in that it further comprises.

The method of claim 1,
The glycerin is a method for producing glycerol carbonate, characterized in that it comprises a composition containing glycerin.

The method according to any one of claims 1 to 3,
The base catalyst is a method for producing glycerol carbonate, characterized in that 0.01wt% to 3.0wt%.

The method of claim 4, wherein
The base catalyst is a method for producing glycerol carbonate, characterized in that 0.08wt% to 0.2wt%.

The method according to any one of claims 1 to 3,
The first reaction step is a method for producing glycerol carbonate, characterized in that the reaction occurs by reflux operation.

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