KR102337169B1 - Preparing method for alkoxy-methylfurfural and 2,5-furandicarboxylic acid from fructose - Google Patents

Abstract

The present invention comprises the steps of (a) preparing a mixed solution by mixing fructose and an organic solvent; (b) heating and reacting the mixed solution under a solid acid catalyst to prepare alkoxy-methyl furfural; (c) separating the solid acid catalyst from the alkoxy-methyl furfural solution mixed with the solid acid catalyst by filtration; and (d) preparing 2,5-furandicarboxylic acid by pressurizing and reacting the solution from which the solid acid catalyst is separated under an oxidation catalyst to prepare 2,5-furandicarboxylic acid. do.
Therefore, 2,5-furandicarboxylic acid can be economically prepared from fructose.

Description

Method for preparing alkoxy-methylfurfural and 2,5-furandicarboxylic acid from fructose {Preparing method for alkoxy-methylfurfural and 2,5-furandicarboxylic acid from fructose}

The present invention relates to a method for producing 2,5-furandicarboxylic acid from fructose, and more particularly, an alkoxy intermediate from fructose using a solid acid catalyst. -Methyl furfural (alkoxy-methylfurfural) and relates to a method for preparing 2,5-furandicarboxylic acid therefrom.

2,5-Furandicarboxylic acid (2,5-Furandicarboxylic acid, hereinafter 'FDCA') is an organic compound in which two carboxylic acids are bonded to a furan ring, and interest has recently increased as an alternative to petroleum-derived terephthalic acid. is a chemical substance in

In addition, FDCA can be manufactured from renewable resources and is an intermediate used in various fields such as pesticides, pharmaceuticals, pesticides, pharmaceuticals, or antibacterial agents.

In general, FDCA synthesizes FDCA by oxidizing 5-hydroxymethyl furfural (hereinafter 'HMF') induced by dehydration of hexose derivatives through a catalyst.

Oxidation of HMF produces diformylfuran (DFF) or hydroxymerylfurancarboxylic acid (5-hydroxymethyl-2-furancarboxylic acid, HFCA) as an intermediate product, and formylfurancarboxylic acid (5 -formyl-2-furancarboxylic acid, FCA) to produce FDCA.

On the other hand, fructose is a monosaccharide having a ketone as a reducing group, is one of hexoses, and is widely present in the plant world.

In order to prepare FDCA from fructose, HMF is prepared through fructose dehydration in the first step, and oxidation of HMF is performed in the second step.

When the first step, the dehydration of fructose, is performed in an aqueous solution, since the generated HMF is easily decomposed into levulinic acid and formic acid by the secondary reaction with water, in order to increase the yield of HMF, a high boiling organic solvent (ex. 1-Butanol, GVL, DMF, etc.) is advantageously used (Non-Patent Document 1, Green Chem., Non-Patent Document 2 2015, 17, 3310; Green Chem., 2011, 13, 754).

In order to increase the yield of FDCA in the oxidation reaction of HMF, it is advantageous to perform the reaction in an aqueous solution (Patent Document 1, Korean Patent Application Laid-Open No. 10-2018-7018309)

Therefore, in order to prepare FDCA in high yield from fructose, HMF must be separated from the organic solvent before HMF oxidation after HMF is prepared in a high boiling point organic solvent.

However, a lot of effort is required to separate the organic solvent from HMF, and loss of HMF cannot be avoided in the separation process.

For example, when the solvent is removed by evaporation, the reaction temperature must be maintained below 50° C. in order not to decompose HMF.

Accordingly, very low pressure is required to remove the high boiling point solvent, which is almost impossible and not economical to carry out in a large-scale industrial process.

As another method, techniques for separating HMF from high boiling point organic solvents using an organic solvent extractant have been introduced, but there is a problem in that efficiency is lowered due to the limitation of HMF solubility in organic solvent extractants, which is also not economical. . (Non-patent document 3. Nature, 2007, 447, 982)

Therefore, in order to economically produce FDCA from fructose, it is ideal to immediately proceed with the oxidation reaction without additional post-treatment after the first-step fructose dehydration reaction.

Also, a method for generating FDCA using a homogeneous catalyst such as Co/Mn/Br in an acetic acid medium in HMF oxidation is known, but it is difficult to recover and reuse the catalyst, and it is not preferable because there is a problem of environmental pollution due to waste generation.

Therefore, as an alternative to the homogeneous catalyst technology, it is very necessary to develop a manufacturing method for increasing the yield of FDCA using a heterogeneous catalyst.

(1) Republic of Korea Patent Publication No. 10-2018-7018309 (published on August 13, 2018)

(1) Green Chem., 2015, 17, 3310 (2) Green Chem., 2011, 13, 754 (3) Nature, 2007, 447, 982

Accordingly, the present invention is to provide a method for economically producing FDCA from fructose.

Specifically, it provides a catalytic process technology for producing FDCA without a process of separating intermediates after dehydration of fructose using a solid acid catalyst, and a highly economical catalyst by using a heterogeneous catalyst instead of a homogeneous catalyst in the FDCA production step A method for preparing FDCA by replacing the material is provided.

The problem to be solved by the present invention is not limited to the problem(s) mentioned above, and another problem(s) not mentioned will be clearly understood by those skilled in the art from the following description.

In order to solve the above problems, the method for producing alkoxy-methylfurfural from fructose according to an embodiment of the present invention is

(a-1) preparing a mixed solution by mixing fructose and an organic solvent;

(a-2) heating and reacting the mixed solution under a solid acid catalyst to prepare alkoxy-methyl furfural; and

(a-3) separating the solid acid catalyst from the alkoxy-methyl furfural solution through filtration; includes

In addition, the organic solvent may be methanol or ethanol.

In addition, the solid acid catalyst may be one in which sulfonic acid (-SO ₃ H) is bonded as a functional group using graphene oxide or activated carbon as a support.

In addition, the filtration may be performed using filter paper after cooling the alkoxy-methyl furfural solution to room temperature at 20 to 30 °C.

A method for preparing 2,5-furandicarboxylic acid from alkoxy-methylfurfural according to another embodiment of the present invention is

2,5-furandicarboxylic acid can be prepared by pressurizing and reacting the alkoxy-methylfurfural solution under an oxidation catalyst.

In addition, the pressurization may pressurize oxygen gas or air at 10 to 30 bar for 1 to 3 hours.

In addition, the oxidation catalyst is activated carbon, zinc oxide, silicon dioxide, zirconium dioxide (ZrO ₂ ), hydrotalcite, cerium oxide and aluminum oxide (Al ₂ O ₃ ) on a support which is any one selected from the group consisting of

It may be characterized in that any one metal selected from the group consisting of gold, platinum, palladium and ruthenium is supported.

The method for preparing 2,5-furandicarboxylic acid from fructose according to another embodiment of the present invention is

(a) preparing a mixed solution by mixing fructose and an organic solvent;

(b) heating and reacting the mixed solution under a solid acid catalyst to prepare alkoxy-methyl furfural;

(c) separating the solid acid catalyst from the alkoxy-methyl furfural solution mixed with the solid acid catalyst by filtration; and

(d) preparing 2,5-furandicarboxylic acid by pressurizing and reacting the solution from which the solid acid catalyst is separated under an oxidation catalyst.

In addition, the organic solvent may be methanol or ethanol.

In addition, the solid acid catalyst may be one in which sulfonic acid (-SO ₃ H) is bonded as a functional group using graphene oxide or activated carbon as a support.

In addition, the pressurization may pressurize oxygen gas or air at 10 to 30 bar for 1 to 3 hours.

In addition, the oxidation catalyst is activated carbon, zinc oxide, silicon dioxide, zirconium dioxide (ZrO ₂ ), hydrotalcite, cerium oxide and aluminum oxide (Al ₂ O ₃ ) Gold, platinum, palladium on a support that is any one selected from the group consisting of And any one metal selected from the group consisting of ruthenium may be supported.

According to the present invention, 2,5-furandicarboxylic acid can be economically prepared from fructose, which is very abundant in the plant kingdom.

In addition, after dehydration of fructose using a solid acid catalyst, the oxidation reaction can proceed immediately without additional post-treatment.

In addition, by reacting fructose with a solid acid catalyst, alkoxy-methylfurfural can be prepared in a very high yield.

In addition, after preparing alkoxy-methyl furfural, it is possible to prepare and recover 2,5-furandicarboxylic acid in high yield using a more economical heterogeneous oxidation catalyst.

In addition, after dehydration from fructose, 2,5-furandicarboxylic acid can be prepared and recovered by a one-pot process without a separate process of isolating the intermediate.

In addition, it is possible to greatly reduce the manufacturing cost by greatly reducing the manufacturing process of 2,5-furandicarboxylic acid from fructose.

The effect of the present invention is not limited to the above-described effect, and it should be understood to include all effects that can be inferred from the configuration of the invention described in the detailed description or claims of the present invention.

1 is a process flow chart showing the process of the alkoxy-methylfurfural (alkoxy-methylfurfural) manufacturing method using a solid acid catalyst according to an embodiment of the present invention.
2 is a process flow diagram showing the process of a method for producing 2,5-furandicarboxylic acid using a catalyst according to another embodiment of the present invention.

Hereinafter, preferred embodiments according to the present invention will be described in detail with reference to the accompanying drawings.

Advantages and features of the present invention, and a method of achieving the same, will become apparent with reference to the embodiments described below in detail in conjunction with the accompanying drawings.

However, the present invention is not limited by the embodiments disclosed below, but will be implemented in a variety of different forms, and only these embodiments allow the disclosure of the present invention to be complete, and common knowledge in the art to which the present invention pertains It is provided to fully inform those who have the scope of the invention, and the present invention is only defined by the scope of the claims.

In addition, in the description of the present invention, when it is determined that related known techniques may obscure the gist of the present invention, a detailed description thereof will be omitted.

The present inventors found that when the dehydration reaction of fructose is performed in an aqueous solution, 5-hydroxymethyl-2-furfural (hereinafter 'HMF') produced is a secondary reaction with water. After confirming that it is easily decomposed into levulinic acid and formic acid by After removal, the final product, 2,5-furandicarboxylic acid (hereinafter 'FDCA'), is produced in high yield through oxidation using a heterogeneous oxidation catalyst without a separate treatment process. The present invention was completed by confirming what could be obtained.

As far as the present inventors know, after preparing alkoxy-methylfurfural from fructose, FDCA is prepared through oxidation using a heterogeneous oxidation catalyst without alkoxy-methylfurfural separation process. The method has not been disclosed.

1 is a process flow diagram showing a process of a method for preparing alkoxy-methylfurfural from fructose according to an embodiment of the present invention, and FIG. , It is a process flow diagram showing the process of the method for producing 5-furandicarboxylic acid.

The present invention relates to a method for producing an intermediate alkoxy-methyl furfural from fructose using a solid acid catalyst, and 2,5-furandicar in high yield by reacting the intermediate alkoxy-methyl furfural with a heterogeneous oxidation catalyst. Provided is a method for preparing 2,5-furandicarboxylic acid from fructose, including a method for preparing the acid.

First, referring to FIG. 1 , the method for preparing alkoxy-methylfurfural from fructose according to an embodiment of the present invention is

(a-1) preparing a mixed solution by mixing fructose and an organic solvent;

(a-2) heating and reacting the mixed solution under a solid acid catalyst to prepare alkoxy-methyl furfural; and

(a-3) separating the solid acid catalyst by filtering the mixed solution containing the alkoxy-methyl furfural;

First, a mixed solution is prepared by mixing fructose and an organic solvent (S10).

The fructose is a carbohydrate and is converted into alkoxy-methylfurfural by dehydration.

The alkoxy-methylfurfural is 5-methoxymethylfurfural (hereinafter 'MMF') or 5-ethoxymethylfurfural (hereinafter 'EMF').

The organic solvent is methanol or ethanol.

_{C 3} or higher alcohol other than methanol or ethanol is difficult to convert to alkoxy-methyl furfural by dehydrating fructose using a solid acid catalyst, and there is a problem of generating by-products after the reaction.

Alkoxy-methyl furfural can be prepared by heating and reacting the mixed solution under a solid acid catalyst (S20).

The solid acid catalyst acts as a proton donor or electron acceptor and is used as a catalyst for dehydration.

The solid acid catalyst may be one in which sulfonic acid (-SO ₃ H) is bonded as a functional group using graphene oxide or activated carbon as a support.

Hereinafter, GO-SO ₃ H means that sulfonic acid is bonded to graphene oxide, and AC-SO ₃ H means that sulfonic acid is bonded to activated carbon.

In the graphene oxide and activated carbon, the sulfonic acid functional group acts as a Bronsted acidic function.

Therefore, the solid acid catalyst has very high catalytic activity and is very advantageous for dehydration.

Other than the solid acid catalyst, the conversion rate of fructose is low, and a reaction temperature of 90° C. or higher is required during the heating reaction, thereby reducing process efficiency.

The heating may be performed at 60 to 80 °C for 12 to 32 hours.

In the heating range, fructose may be converted to 100%, and EMF or MMF may be prepared in a yield of 70 to 90%.

When the heating temperature is lower than 60 °C, there is a disadvantage in that the dehydration reaction rate of fructose is low, and when it is higher than 80 °C, there are problems in that loss and side reactions occur due to evaporation of alcohol during atmospheric pressure reaction.

A solid acid catalyst is separated from the mixed solution containing the alkoxy-methyl furfural through filtration (S30).

The filtration may be performed using filter paper after cooling the alkoxy-methyl furfural solution to 20 to 30° C. to room temperature.

The reaction catalyst can be removed through the filtration.

If the solid acid catalyst is not separated by filtration, there is a problem in that by-products are generated or the FDCA production rate is lowered in the subsequent step of generating FDCA by oxidizing alkoxy-methyl furfural under the catalyst.

Therefore, EMF or MMF can be prepared using a solid acid catalyst, and unlike the conventional separate treatment for separating the high boiling point organic solvent phase, the solid acid catalyst is very effectively removed through filtration and alkoxy-methyl furfural in high yield. (alkoxy-methylfurfural) can be prepared.

A method for preparing 2,5-furandicarboxylic acid from alkoxy-methylfurfural according to another embodiment of the present invention is

2,5-furandicarboxylic acid can be prepared by pressurizing and reacting the alkoxy-methylfurfural solution under an oxidation catalyst.

The pressurization may pressurize oxygen gas or air at 10 to 30 bar for 1 to 3 hours.

FDCA can be produced with high efficiency using an oxidation catalyst within the pressure range, and when it does not reach the above range, the yield according to the oxidation reaction is low, and when it exceeds the above range, the energy is not increased without increasing the reaction yield. There is a problem with more consumption.

The oxidation catalyst is activated carbon, zinc oxide, silicon dioxide, zirconium dioxide (ZrO ₂ ), hydrotalcite, cerium oxide and aluminum oxide (Al ₂ O ₃ ) Gold, platinum, palladium and Any one metal selected from the group consisting of ruthenium may be supported.

The oxidation catalyst is a heterogeneous catalyst, and since it is easy to separate the catalyst from FDCA after oxidation compared to a conventional homogeneous catalyst, it is environmentally friendly and can greatly reduce process costs.

2, the method for preparing 2,5-furandicarboxylic acid using a catalyst according to another embodiment of the present invention is

(a) preparing a mixed solution by mixing fructose and an organic solvent;

(b) heating and reacting the mixed solution under a solid acid catalyst to prepare alkoxy-methyl furfural;

(c) separating the solid acid catalyst from the alkoxy-methyl furfural solution mixed with the solid acid catalyst by filtration; and

(d) pressurizing and reacting the solution from which the solid acid catalyst is separated under an oxidation catalyst to prepare 2,5-furandicarboxylic acid.

In addition, the method for preparing FDCA from fructus using the solid acid catalyst and the oxidation catalyst may be performed according to Scheme 1 below.

[Scheme 1]

In an embodiment of the present invention, fructose is mixed with ethanol under a solid acid catalyst to generate EMF as an intermediate, and is converted to FDCA by reacting with a Pt/C oxidation catalyst under oxygen pressure.

First, a mixed solution is prepared by mixing fructose and an organic solvent (S100).

The organic solvent may be methanol or ethanol.

_{C 3} or higher alcohol other than methanol or ethanol is difficult to convert to alkoxy-methyl furfural by dehydrating fructose using a solid acid catalyst, and there is a problem of generating by-products after the reaction.

The mixed solution is heated and reacted under a solid acid catalyst to prepare alkoxy-methyl furfural (S200).

The solid acid catalyst may be one in which sulfonic acid (-SO ₃ H) is bonded as a functional group using graphene oxide or activated carbon as a support.

It is difficult for the sulfonic acid to bind to a functional group other than the support.

The solid acid catalyst to which the sulfonic acid is bonded as a functional group acts as a proton donor or electron acceptor and is used as a catalyst for dehydration.

In the graphene oxide and activated carbon, the sulfonic acid functional group acts as a Bronsted acidic function.

Therefore, the solid acid catalyst has very high catalytic activity and is very advantageous for dehydration.

Other than the solid acid catalyst, the conversion rate of fructose is low, and a reaction temperature of 90° C. or higher is required during the heating reaction, thereby reducing process efficiency.

The heating may be performed at 60 to 80 °C for 12 to 32 hours.

In the heating range, fructose may be converted to 100%, and EMF or MMF may be prepared in a yield of 70 to 90%.

The solid acid catalyst is separated by filtration from the alkoxy-methyl furfural solution mixed with the solid acid catalyst (S300).

The reaction catalyst can be removed through the filtration.

EMF or MMF can be prepared using a solid acid catalyst, and unlike the conventional separate treatment for separating the high boiling point organic solvent phase, the solid acid catalyst is very effectively removed through filtration and EMF or MMF is obtained at a high conversion rate. Alkoxy-methylfurfural (alkoxy-methylfurfural) can be prepared.

The solution from which the solid acid catalyst is separated is pressurized under an oxidation catalyst and reacted to prepare 2,5-furandicarboxylic acid (S400).

The pressurization may pressurize oxygen gas or air at 10 to 30 bar for 1 to 3 hours.

FDCA can be produced with high efficiency using an oxidation catalyst within the pressure range, and when it does not reach the above range, the yield according to the oxidation reaction is low, and when it exceeds the above range, the energy is high without increasing the reaction yield There is a problem with more consumption.

The oxidation catalyst is activated carbon, zinc oxide, silicon dioxide, hydrotalcite, cerium oxide (CeO ₂ ) and aluminum oxide (Al ₂ O ₃ ) on a support selected from the group consisting of gold, platinum, palladium and ruthenium Any one metal selected from the group may be supported.

The oxidation reaction can be performed by preparing a heterogeneous catalyst using the support, and the recovery and reuse of the catalyst is easy, thereby reducing the overall process cost and increasing the process efficiency.

The oxidation reaction of EMF or MMF is performed under the pressure within the above range under the oxidation catalyst, and FDCA can be prepared in a yield of 90% or more.

Hereinafter, preferred examples are presented to help the understanding of the present invention, but the following examples are only illustrative of the present invention and the scope of the present invention is not limited to the following examples.

Experimental Example 1. Preparation of solid acid catalyst

According to the literature (PP Upare, J.-W. Yoon, H.-Y. Kang, DW Hwang, YK Hwang, HH Kung, J.-S. Chang, Green Chem. 15 (2013) 2935-2943) graphene Sulfonation of the oxide and activated carbon was performed to prepare solid acid catalysts GO-SO ₃ H and AC-SO ₃ H.

The content of sulfone groups (S-density, mmol/g) was confirmed through elemental analysis of the sulfonated material.

AC-SO ₃ H contained 2.5 mmol/g -SO ₃ H group, which was confirmed to be about twice or more than 1.2 mmol/g of _{GO-SO 3 H, so that AC-SO 3} H had a stronger acidic point. site) was confirmed.

Also, AC-SO ₃ H and GO-SO ₃ H had higher S-density compared to MTS-GO (methoxytrimethylsiliane-graphene oxide) or Zr(SO ₄ ) ₂ catalyst, so it was predicted to be very effective for dehydration of fructose.

Example 1. Preparation of 5-ethoxymethylfurfural (EMF) from fructose

_{1 g of fructose was mixed with 9 ml of ethanol and 1.0 g of a solid acid catalyst (GO-SO 3} H) in which graphene oxide was bound to sulfonic acid, heated to 70 °C, and then the reaction was carried out for 24 hours. After the reaction, the sample was cooled to room temperature, and the GO-SO ₃ H catalyst was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 100% and the EMF yield was 72%.

Example 2. Preparation of 5-ethoxymethylfurfural (EMF) from fructose

After mixing 1 g of fructose with 9 ml of ethanol _{and 1.0 g of a GO-SO 3} H catalyst, the mixture was heated to 70° C. and the reaction was carried out for 30 hours. After the reaction, the sample was cooled to room temperature, and the GO-SO ₃ H catalyst was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 100% and the EMF yield was 90%.

Example 3. Preparation of 5-ethoxymethylfurfural (EMF) from fructose

After mixing 1 g of fructose with 9 ml of ethanol _{and 1.0 g of AC-SO 3} H catalyst, the mixture was heated to 70° C. and the reaction was carried out for 32 hours. After the reaction, the sample was cooled to room temperature, and the AC-SO3H catalyst was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 100% and the EMF yield was 91%.

The EMF/ethanol solution obtained through the above process was heated to 60 °C, maintained for 48 hours, and then cooled to room temperature.

As a result of analyzing the solution by liquid chromatography, there was little change in the concentration of EMF.

Therefore, when EMF is prepared in ethanol solvent using AC-SO ₃ H catalyst, EMF can be obtained in a high yield of 90% or more, and when the catalyst is removed after completion of the catalytic reaction, the secondary reaction of EMF can be suppressed. It can be seen that there is

Example 4. Preparation of 5-methoxymethylfurfural (MMF) from fructose

After mixing 1 g of fructose with 9 ml of methanol _{and 1.0 g of GO-SO 3} H catalyst, the mixture was heated to 60° C. and the reaction was carried out for 30 hours. After the reaction, the sample was cooled to room temperature, and the GO-SO ₃ H catalyst was separated from the solution through filtration. As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 100% and the MMF yield was 91%.

The MMF/methanol solution obtained through the above process was heated to 60 °C, maintained for 48 hours, and then cooled to room temperature. As a result of analyzing the solution by liquid chromatography, there was little change in the concentration of MMF.

Therefore, when MMF is prepared in methanol solvent using AC-SO ₃ H catalyst, MMF can be obtained in a high yield of 90% or more, and when the catalyst is removed after completion of the catalytic reaction, the secondary reaction of MMF can be suppressed. It can be seen that

Example 5. Preparation of 5-Methoxymethylfurfural (MMF) from fructose

_{1 g of fructose was mixed with 9 ml of methanol and 1.5 g of a catalyst (hereinafter, 'AC-SO 3} H') in which sulfonic acid was bonded to an activated carbon support as a functional group, heated to 60° C., and reacted for 21 hours.

After the reaction, the sample was cooled to room temperature, and the AC-SO ₃ H catalyst was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 100% and the MMF yield was 90%.

Thus, the AC-SO case of preparing MMF on a methanol solvent using a ₃ H catalyst, AC-SO ₃ as H is increased amount of catalyst, and the MMF production rate to find out faster, this AC-SO ₃ H catalyst with By controlling the amount, it is possible to control the MMF yield and reaction time.

Example 6. Preparation of 5-methoxymethylfurfural (MMF) from fructose

After mixing 1 g of fructose with methanol 9 ml and _{1.0 g of AC-SO 3} H catalyst, the mixture was heated to 80° C. and the reaction was carried out for 12 hours.

After the reaction, the sample was cooled to room temperature, and the AC-SO ₃ H catalyst was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 100% and the MMF yield was 79%.

Checking Examples 1 to 6, it can be seen that fructose can be mixed with a solid acid catalyst and heated to obtain EMF or MMF, which is alkoxy-methylfurfural, at a high conversion rate.

Example 7. Preparation of FDCA from EMF

The EMF / ethanol solution prepared in Example 1 was mixed with 0.5 g of a catalyst coated with platinum on an activated carbon support (hereinafter 'Pt (5%) / C'), heated to 100 ° C, and then heated to 15 bar using _{O 2 gas.} After increasing the pressure, the reaction was carried out for 2 hours.

After the reaction, the sample was cooled to room temperature at 27 °C, and the solid mixture was separated from the solution through filtration.

The solid mixture was mixed with 10 ml of a dimethylformamide (hereinafter 'DMF') solvent and filtered to separate the catalyst from the solution.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the EMF conversion rate was 100% and the FDCA yield was 97%.

When a heterogeneous oxidation catalyst coated with a small amount of platinum on an activated carbon support is used, it can be easily separated from FDCA through filtration after FDCA is generated, so the reaction solution and catalyst can be easily separated and the catalyst can be reused. .

Example 8. Preparation of FDCA from EMF

The EMF/ethanol solution prepared in Example 1 was mixed with 0.5 g of a catalyst coated with gold on a hydrotalcite support (hereinafter 'Au(5%)/hydrotalcite') catalyst, heated to 100 ℃, and then _{using O 2} gas. After raising the pressure to 15 bar, the reaction was carried out for 2 hours.

After the reaction, the sample was cooled to room temperature, and the solid mixture was separated from the solution by filtration.

After mixing the solid mixture with 10 ml of DMF solvent, the catalyst was separated from the solution through filtration. As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the EMF conversion rate was 100% and the FDCA yield was 95%.

Example 9. Preparation of FDCA from EMF

The EMF/ethanol solution prepared in Example 1 was mixed with 0.5 g of Au (5%)/hydrotalcite catalyst, heated to 100° C., and the pressure was increased to 10 bar using _{O 2 gas, followed by reaction for 2 hours.}

After the reaction, the sample was cooled to room temperature, and the solid mixture was separated from the solution by filtration.

After mixing the solid mixture with 10 ml of DMF solvent, the catalyst was separated from the solution through filtration. As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the EMF conversion rate was 100% and the FDCA yield was 90%.

Example 10. Preparation of FDCA from EMF

The EMF/ethanol solution prepared in Example 1 was mixed with 0.5 g of a catalyst coated with ruthenium on an activated carbon support (hereinafter 'Ru (5%)/C'), heated to 100 ° C, and then heated to 15 bar using _{O 2 gas.} After increasing the pressure, the reaction was carried out for 2 hours.

After the reaction, the sample was cooled to room temperature, and the solid mixture was separated from the solution by filtration.

After mixing the solid mixture with 10 ml of DMF solvent, the catalyst was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the EMF conversion rate was 100% and the FDCA yield was 96%.

Example 11. Preparation of FDCA from EMF

The EMF / ethanol solution prepared in Example 1 was mixed with 0.5 g of a catalyst coated with ruthenium on a cerium oxide support (hereinafter 'Ru (5%) / CeO ₂ '), heated to 100 ° C, and then 15 using _{O 2 gas.} After raising the pressure to bar, the reaction was carried out for 2 hours.

After the reaction, the sample was cooled to room temperature, and the solid mixture was separated from the solution by filtration.

After mixing the solid mixture with 10 ml of DMF solvent, the catalyst was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the EMF conversion rate was 100% and the FDCA yield was 95%.

Example 12. Preparation of FDCA from EMF

The EMF / ethanol solution prepared in Example 1 was mixed with 0.5 g of a catalyst coated with palladium on an activated carbon support (hereinafter 'Pd (5%) / C') catalyst, heated to 100 ° C., and then 15 bar using _{O 2 gas.} After raising the pressure to the furnace, the reaction was carried out for 2 hours.

After the reaction, the sample was cooled to room temperature, and the solid mixture was separated from the solution by filtration.

After mixing the solid mixture with 10 ml of DMF solvent, the catalyst was separated from the solution through filtration. As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the EMF conversion rate was 100% and the FDCA yield was 92%.

Example 13. Preparation of FDCA from EMF

The EMF/ethanol solution prepared in Example 1 was mixed with 0.5 g of a catalyst coated with platinum on an activated carbon support (hereinafter 'Pt (5%)/C') catalyst, heated to 100 ° C, and then pressured to 20 bar using air. After loading, the reaction was carried out for 2 hours.

After the reaction, the sample was cooled to room temperature, and the solid mixture was separated from the solution by filtration.

After mixing the solid mixture with 10 ml of DMF solvent, the catalyst was separated from the solution through filtration. As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the EMF conversion rate was 100% and the FDCA yield was 93%.

Comparative Example 1. Preparation of 5-ethoxymethylfurfural (EMF) from fructose

After mixing 1 g of fructose with 9 ml of ethanol and 1.0 g of Amberlsyt-15 resin, which is a commercial catalyst, the mixture was heated to 70° C. and the reaction was carried out for 24 hours.

After the reaction, the sample was cooled to room temperature, and the amberlyst-15 resin was separated from the solution through filtration. As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 61% and the EMF yield was 31%.

Comparative Example 2. Preparation of 5-ethoxymethylfurfural (EMF) from fructose

After mixing 1 g of fructose with 9 ml of ethanol and 1.0 g of Amberlsyt-15 resin, the mixture was heated to 80° C. and the reaction was carried out for 24 hours. After the reaction, the sample was cooled to room temperature, and the amberlyst-15 resin was separated from the solution through filtration. As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 73% and the EMF yield was 38%.

Comparative Example 3. Preparation of 5-ethoxymethylfurfural (EMF) from fructose

After mixing 1 g of fructose with 9 ml of ethanol and 1.0 g of Amberlsyt-131 resin, the mixture was heated to 80° C. and the reaction was carried out for 46 hours. After the reaction, the sample was cooled to room temperature, and the amberlyst-15 resin was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 100% and the EMF yield was 86%.

Comparative Example 4. Preparation of 5-hydroxymethylfurfural (HMF) from fructose

After mixing 1 g of fructose with 9 ml of 1-butanol and 1.0 g of Amberlsyt-15 resin, the mixture was heated to 100° C. and the reaction was carried out for 5 hours. After the reaction, the sample was cooled to room temperature, and the amberlyst-15 resin was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the fructose conversion rate was 100% and the HMF yield was 86%.

Comparative Example 5. Preparation of 5-hydroxymethylfurfural (HMF) from fructose

After mixing 1 g of fructose with 9 ml of isopropyl alcohol and 1.0 g of Amberlsyt-15 resin, the mixture was heated to 100 ℃ and the reaction was carried out for 5 hours. After the reaction, the sample was cooled to room temperature, and the amberlyst-15 resin was separated from the solution through filtration.

As a result of analyzing the separated solution by liquid chromatography, it was confirmed that the conversion rate of fructose was 100% and the yield of HMF was 42%.

Therefore, it was confirmed that when Amberlyst resin, which is a conventional commercial catalyst, was used, the EMF production rate was slow and the yield was very low.

In addition, it can be seen that, when isopropyl alcohol or 1-butanol, rather than methanol or ethanol, is used as a solvent, alkoxy-methyl furfural is not produced and 5-hydroxymethyl furfural (HMF) is mainly produced. have.

Comparative Example 6. Preparation of FDCA from EMF

After heating the EMF/ethanol solution prepared in Example 1 to 100 °C without an oxidation catalyst, the pressure was raised to 20 bar using air, and then the reaction was carried out for 2 hours.

After the reaction, the sample was cooled to room temperature, and the solid mixture was mixed with 10 ml of a DMF solvent and analyzed by liquid chromatography. As a result, it was confirmed that the EMF conversion rate was 15% and the FDCA yield was 10%.

Up to now, the method for preparing alkoxy-methyl furfural from fructose, the method for preparing 2,5-furandicarboxylic acid from alkoxy-methyl furfural, and 2,5-furandica from fructose according to Examples of the present invention Although specific examples have been described with respect to the method for preparing carboxylic acid, it is apparent that various implementation modifications are possible within the limits that do not depart from the scope of the present invention.

Therefore, the scope of the present invention should not be limited to the described embodiments, but should be defined by the following claims as well as the claims and equivalents.

That is, it should be understood that the above-described embodiments are illustrative in all respects and not restrictive, and the scope of the present invention is indicated by the claims to be described later rather than the detailed description, and the meaning and scope of the claims; All changes or modifications derived from the concept of equivalents should be construed as being included in the scope of the present invention.

Claims (12)

A method for preparing 2,5-furandicarboxylic acid from alkoxy-methylfurfural prepared from fructose, the method comprising:
After reacting a mixed solution of fructose and an organic solvent under a solid acid catalyst, the solid acid catalyst is separated by filtration to prepare an alkoxy-methyl furfural solution (first step),
The alkoxy-methyl furfural solution is pressurized under a heterogeneous oxidation catalyst and reacted to prepare 2,5-furandicarboxylic acid (second step),
The organic solvent is characterized in that methanol or ethanol,
A process for the preparation of 2,5-furandicarboxylic acid from alkoxy-methylfurfural.
According to claim 1,
The pressurization is a method for producing 2,5-furandicarboxylic acid from alkoxy-methyl furfural, characterized in that pressurizing oxygen gas or air at 10 to 30 bar for 1 to 3 hours.
According to claim 1,
The oxidation catalyst is
Activated carbon, zinc oxide, silicon dioxide, zirconium dioxide (ZrO ₂ ), hydrotalcite, cerium oxide and aluminum oxide (Al ₂ O ₃ ) on a support which is any one selected from the group consisting of
A method for producing 2,5-furandicarboxylic acid from alkoxy-methylfurfural, wherein any one metal selected from the group consisting of gold, platinum, palladium and ruthenium is supported.
(a) preparing a mixed solution by mixing fructose and an organic solvent;
(b) heating and reacting the mixed solution under a solid acid catalyst to prepare alkoxy-methyl furfural;
(c) separating the solid acid catalyst from the alkoxy-methyl furfural solution mixed with the solid acid catalyst by filtration; and
(d) preparing 2,5-furandicarboxylic acid by pressurizing and reacting the solution from which the solid acid catalyst is separated under a heterogeneous oxidation catalyst;
The organic solvent is characterized in that methanol or ethanol,
Method for preparing 2,5-furandicarboxylic acid from fructose.
delete 5. The method of claim 4,
The solid acid catalyst is
A method for producing 2,5-furandicarboxylic acid from fructose, characterized in that _{sulfonic acid (-SO 3} H) is bonded as a functional group using graphene oxide or activated carbon as a support.
5. The method of claim 4,
The filtration is
A method for producing alkoxy-methyl furfural from fructose, characterized in that the alkoxy-methyl furfural solution is cooled to 20 to 30 ° C. to room temperature and then carried out using filter paper.
5. The method of claim 4,
The pressurization is
A method for producing 2,5-furandicarboxylic acid from fructose using a catalyst, characterized in that oxygen gas or air is pressurized at 10 to 30 bar for 1 to 3 hours.
5. The method of claim 4,
The oxidation catalyst is
Activated carbon, zinc oxide, silicon dioxide, zirconium dioxide (ZrO ₂ ), hydrotalcite, cerium oxide and aluminum oxide (Al ₂ O ₃ ) on a support which is any one selected from the group consisting of
A method for producing 2,5-furandicarboxylic acid from fructose, characterized in that any one metal selected from the group consisting of gold, platinum, palladium and ruthenium is supported. delete delete delete

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