Method for purifying 5-hydroxymethylfurfural

Abstract

The present invention relates to the field of the purification of chemicals, and provides a method for purifying 5-hydroxymethylfurfural to address the problems of complex steps and high costs during the purification of 5-hydroxymethylfurfural. The method comprises the following steps: (1) adding crude 5-hydroxymethylfurfural to water, adding activated carbon for adsorption, and after the adsorption is completed, performing filtering and separating, so as to obtain a filtrate; (2) adding an organic solvent to the filtrate obtained in step (1) for extraction, performing separation, taking an organic phase, and subjecting same to rotary evaporation and concentration, so as to obtain a solution to be crystallized; and (3) subjecting said solution obtained in step (2) to cooling crystallization, so as to obtain purified 5-hydroxymethylfurfural. In the method, high-purity 5-hydroxymethylfurfural can be readily obtained by sequentially subjecting crude 5-hydroxymethylfurfural to adsorption with activated carbon, extraction with an organic solvent, and crystallization; and the method is simple to operate, and has low costs.

Description

A method for purifying 5-hydroxymethylfurfural TECHNICAL FIELD

[0001] The present application relates to the field of chemical purification, in particular to a method for purifying 5-hydroxymethylfurfural. BACKGROUND

[0002] 5-hydroxymethylfurfural (HMF) contains a hydroxyl group, an aldehyde group and a highly active furan ring. It can be prepared not only from fructose dehydration, but also from glucose dehydration after isomerization, and even from cellulose directly. Its chemical properties are relatively active, and it can be used to prepare various derivatives through esterification, halogenation, polymerization, oxidation, hydrogenation and condensation, etc. As a monomer for high polymer material synthesis, a raw material for macrocyclic compound synthesis, and an important intermediate raw material for medicine and pesticide, it has important potential application value in various fields. However, these applications also put high requirements on the purity of HMF, so it is of great social value and economic significance to prepare high-purity 5-hydroxymethylfurfural.

[0003] Currently, the purification of 5-hydroxymethylfurfural mainly includes distillation, extraction, activated carbon adsorption, column separation and crystallization, etc. Patents CN105753819A and CN110143936A use column chromatography to separate HMF. The adsorbent skeleton of CN105753819A has furan and imidazole heterocyclic structures, which improves the adsorption capacity of the adsorbent for impurities such as hydroxymethyl formyl furan in 5-hydroxymethylfurfural, and high-purity 5-hydroxymethylfurfural products can be obtained. However, this method is extremely slow in separation speed and is difficult to realize industrial production. Patent CN109651308A discloses a method for purifying HMF by membrane separation. Although this method can obtain high-purity HMF, it has high consumption and low economic benefit. Patent US20150025256A1 uses a crystallization method to separate HMF, but this method has high requirements for raw materials. When the raw material contains many impurities, especially macromolecular humin, the product cannot be well purified. Patents CN111321254A and CN103380120 use extraction and distillation methods to purify HMF, respectively. However, the reaction system after dehydration contains various impurities such as levulinic acid, formic acid and humin. These impurities have similar properties such as boiling point and polarity to HMF, and it is difficult to separate them by simple methods, especially macromolecular humin. At present, there is no effective separation method to remove them. Therefore, an ideal solution is needed.

[0004] SUMMARY

[0005] In order to overcome the problems of complex purification steps and high cost of 5-hydroxymethylfurfural, the present application provides a method for purifying 5-hydroxymethylfurfural. Crude 5-hydroxymethylfurfural is sequentially subjected to activated carbon adsorption, organic solvent extraction and crystallization to obtain high-purity 5-hydroxymethylfurfural, which is simple to operate and low in cost.

[0006] To achieve the above object, the present application adopts the following technical solutions:

[0007] A method for purifying 5-hydroxymethylfurfural, comprising the following steps:

[0008] (1) adding crude 5-hydroxymethylfurfural into water, adding activated carbon for adsorption, and separating the filtrate by filtration after the adsorption is completed;

[0009] (2) adding an organic solvent to the filtrate obtained in step (1) for extraction, separating, and taking the organic phase for rotary evaporation concentration to obtain a crystallization solution;

[0010] (3) cooling and crystallizing the crystallization solution obtained in step (2) to obtain purified 5-hydroxymethylfurfural.

[0011] As a preferred, the crude 5-hydroxymethylfurfural is obtained by dehydration of a saccharide.

[0012] As a preferred, the water is 0.5-10 times, further preferably 1.5-5 times, the weight of the 5-hydroxymethylfurfural.

[0013] As a preferred, the activated carbon is 0.01-0.5 times, further preferably 0.05-0.4 times, the weight of the 5-hydroxymethylfurfural.

[0014] As a preferred, the weight ratio of the organic solvent to water is (1-5):1, preferably (2-3):1.

[0015] As a preferred, the organic solvent is selected from one or more of ethyl acetate, propyl acetate, butyl acetate, pentyl acetate, dichloromethane, chloroform, acetylacetone, cyclohexanone, methyl isobutyl ketone, diethyl ether, isopropyl ether, methyl tert-butyl ether, tetrahydrofuran, and 2-methyltetrahydrofuran; further preferably one of ethyl acetate, dichloromethane, chloroform, cyclohexanone, diethyl ether, isopropyl ether, methyl tert-butyl ether, and tetrahydrofuran.

[0016] As a preferred, the mass ratio of the rotary evaporation concentration is 20-70%, further preferably 25-40%.

[0017] As a preferred, the final temperature of the cooling and crystallization is -30 to -5℃, further preferably -25 to -15℃.

[0018] As a preferred, the cooling and crystallization adopts gradient cooling, specifically: decreasing to 14-16℃ at a rate of 50-150℃ / h, decreasing to 4-6℃ at a rate of 2-10℃ / h, and decreasing to -30 to -5℃ at a rate of 10-30℃ / h.

[0019] Therefore, the present application has the advantages that the crude 5-hydroxymethylfurfural is sequentially subjected to active carbon adsorption, organic solvent extraction and crystallization to obtain high-purity 5-hydroxymethylfurfural, and the operation is simple and the cost is low. DETAILED DESCRIPTION

[0020] The technical solutions of the present application are further described below through specific examples.

[0021] In the present application, the raw materials and equipment used, unless specified otherwise, can be purchased from the market or commonly used in the art. The methods in the examples, unless specified otherwise, are all conventional methods in the art. Unless otherwise specified, the parts are all by weight, the temperature is in ℃ or at ambient temperature, and the pressure is atmospheric pressure or close to atmospheric pressure. Various modifications and combinations of the reaction conditions (such as component concentration, required solvent, solvent mixture, temperature, pressure and other reaction ranges) and conditions that can be used to optimize the purity and yield of the product obtained by the method will only require reasonable conventional experiments to optimize such method conditions.

[0022] EMBODIMENT

[0023] A method for purifying 5-hydroxymethylfurfural, the crude 5-hydroxymethylfurfural is sequentially subjected to active carbon adsorption, organic solvent extraction and crystallization to obtain high-purity 5-hydroxymethylfurfural, and the operation is simple and the cost is low. Specifically, the following steps are included:

[0024] (1) Active carbon adsorption to remove impurities. First, the crude 5-hydroxymethylfurfural is added to water, and the crude 5-hydroxymethylfurfural can be obtained by dehydration of sugars. The weight of water is 0.5-10 times the weight of 5-hydroxymethylfurfural, and is further preferably 1.5-5 times. Then, active carbon is added and stirred to adsorb and remove impurities, and the weight of active carbon is 0.01-0.5 times the weight of 5-hydroxymethylfurfural, and is preferably 0.05-0.4 times. After the adsorption and removal of impurities is completed, the mixture is filtered to separate the filtrate.

[0025] (2) Extraction. An organic solvent is added to the above-mentioned filtrate, and the weight ratio of the organic solvent to water is (1-5):1, and is preferably (2-3):1. The organic solvent is selected from one or more of ethyl acetate, propyl acetate, butyl acetate, pentyl acetate, dichloromethane, chloroform, acetylacetone, cyclohexanone, methyl isobutyl ketone, diethyl ether, isopropyl ether, methyl tert-butyl ether, tetrahydrofuran, and 2-methyltetrahydrofuran; and is further preferably one of ethyl acetate, dichloromethane, chloroform, cyclohexanone, diethyl ether, isopropyl ether, methyl tert-butyl ether, and tetrahydrofuran. The extraction is carried out in a separatory funnel, after vigorous shaking, the mixture is allowed to stand and separate into layers, the extraction liquid is separated, the upper organic phase is taken and concentrated by rotary evaporation to remove the solvent, and the mass ratio of rotary evaporation concentration is 20-70%, and is further preferably 25-40%, to obtain a crystallization solution.

[0026] (3) Crystallization. The above solution to be crystallized is added into a crystallizer to perform cooling crystallization, and the final temperature of the cooling crystallization is -30 to -5°C, and is further preferably -25 to -15°C. The cooling crystallization is performed by gradient cooling, specifically: cooling to 14 to 16°C at a rate of 50 to 150°C / h, cooling to 4 to 6°C at a rate of 2 to 10°C / h, and cooling to -30 to -5°C at a rate of 10 to 30°C / h. After the crystallization reaches the final temperature, solid-liquid separation is performed, the solid phase is dried, and finally 5-hydroxymethylfurfural crystals, i.e. the purified 5-hydroxymethylfurfural, are obtained.

[0027] (4) Purity detection. The purity of the 5-hydroxymethylfurfural is detected by high performance liquid chromatography, and the specific method is as follows: the instrument is Agilent 1260, the column type is Eclipse XDB-C18, the column temperature is 40°C, the ultraviolet detector is used, the mobile phase is 10% water and 90% methanol, the flow rate is 1 mL / min, and the detection wavelength is 283 nm.

[0028] Examples 1-14

[0029] A method for purifying 5-hydroxymethylfurfural is provided. 50 g of 5-hydroxymethylfurfural crude product obtained by dehydrating fructose is added into a beaker, 75 g of water is added, 5 g of activated carbon is added for stirring and adsorption, after the adsorption is completed, the filtrate is collected by filtration, and then the filtrate is transferred into a separatory funnel. 150 g of an extractant is added into the separatory funnel, after being shaken vigorously, the mixture is allowed to stand and separate into two layers, the upper 5-hydroxymethylfurfural organic solution is distilled to separate the solvent, and the concentration is 30%. Subsequently, the solution is added into a crystallizer to perform cooling crystallization, the cooling rate is gradient cooling: first cooling to 15°C at a rate of 100°C / h, then cooling to 5°C at a rate of 5°C / h, and finally cooling to a final temperature of -20°C at a rate of 25°C / h. The mixture after the cooling crystallization is subjected to solid-liquid separation, the solid phase is dried, and finally 5-hydroxymethylfurfural crystals are obtained.

[0030] The difference between Examples 1-14 is that different extractants are used, and the specific types are shown in Table 1. The purity of the 5-hydroxymethylfurfural crystals obtained in Examples 1-14 is detected by high performance liquid chromatography, and the specific method is as follows: the instrument is Agilent 1260, the column type is Eclipse XDB-C18, the column temperature is 40°C, the ultraviolet detector is used, the mobile phase is 10% water and 90% methanol, the flow rate is 1 mL / min, and the detection wavelength is 283 nm. The results are shown in Table 1.

[0031] Table 1. Types of extractants used in Examples 1-14 and purity of 5-hydroxymethylfurfural products

[0032] Examples 15-22

[0033] A method for purifying 5-hydroxymethylfurfural, 50g of 5-hydroxymethylfurfural crude product obtained by dehydrating fructose is added into a beaker, a certain amount of water is added into the beaker, then 10g of activated carbon is added for stirring and adsorption, after the adsorption is completed, the filtrate is collected by filtration, then the filtrate is transferred into a separatory funnel, a certain amount of diethyl ether is added into the separatory funnel, after being shaken vigorously, the mixture is allowed to stand to separate into layers, the upper layer of 5-hydroxymethylfurfural organic solution is distilled to separate the solvent, the concentration is 30%, then the solution is added into a crystallizer for cooling crystallization, the cooling rate adopts gradient cooling, first, the temperature is decreased to 15°C at a rate of 100°C / h, then the temperature is decreased to 5°C at a rate of 5°C / h, finally, the temperature is decreased to a final temperature of -20°C at a rate of 25°C / h, the mixture after the cooling crystallization is subjected to solid-liquid separation, the solid phase is dried, and finally, 5-hydroxymethylfurfural crystals are obtained.

[0034] The difference between examples 15-22 lies in the amount of water added, as shown in Table 2. The purity of 5-hydroxymethylfurfural crystals obtained in examples 15-22 is detected by high performance liquid chromatography, and the specific method is as follows: the instrument is Agilent 1260, the column type is Eclipse XDB-C18, the column temperature is 40°C, the ultraviolet detector is used, the mobile phase is 10% water and 90% methanol, the flow rate is 1mL / min, and the detection wavelength is 283nm. The results are shown in Table 2.

[0035] Table 2. Water addition amount, extractant addition amount and 5-hydroxymethylfurfural product purity of examples 15-22

[0036] Examples 23-29

[0037] A method for purifying 5-hydroxymethylfurfural, 50g of 5-hydroxymethylfurfural crude product obtained by dehydrating fructose is added into a beaker, 150g of water is added into the beaker, then a certain amount of activated carbon is added for stirring and adsorption, after the adsorption is completed, the filtrate is collected by filtration, then the filtrate is transferred into a separatory funnel, 300g of methyl tert-butyl ether is added into the separatory funnel, after being shaken vigorously, the mixture is allowed to stand to separate into layers, the upper layer of 5-hydroxymethylfurfural organic solution is distilled to separate the solvent, the concentration is 30%, then the solution is added into a crystallizer for cooling crystallization, the cooling rate adopts gradient cooling, first, the temperature is decreased to 15°C at a rate of 100°C / h, then the temperature is decreased to 5°C at a rate of 5°C / h, finally, the temperature is decreased to a final temperature of -20°C at a rate of 25°C / h, the mixture after the cooling crystallization is subjected to solid-liquid separation, the solid phase is dried, and finally, 5-hydroxymethylfurfural crystals are obtained.

[0038] The difference between Examples 23-29 is the amount of activated carbon added, as shown in Table 3. The purity of the 5-hydroxymethylfurfural crystals obtained in Examples 23-29 was determined by high performance liquid chromatography using the following method: the instrument was an Agilent 1260, the column type was Eclipse XDB-C18, the column temperature was 40°C, the UV detector, the mobile phase was 10% water and 90% methanol, the flow rate was 1 mL / min, and the detection wavelength was 283 nm. The results are shown in Table 3.

[0039] Table 3. Amount of activated carbon added and purity of 5-hydroxymethylfurfural product in Examples 23-29

[0040] Examples 30-34

[0041] A method for purifying 5-hydroxymethylfurfural, 50 g of 5-hydroxymethylfurfural crude product obtained by dehydrating fructose was added to a beaker, 200 g of water was added, then 10 g of activated carbon was added and stirred and adsorbed, after adsorption was complete, the filtrate was collected by filtration, then the filtrate was transferred to a separatory funnel, a certain amount of methyl tert-butyl ether was added to the separatory funnel, after vigorous shaking, the layers were allowed to separate, the upper layer of 5-hydroxymethylfurfural organic solution was distilled to separate the solvent, concentrated to 30%, then the solution was added to a crystallizer and cooled to crystallize, the cooling rate was gradient cooling: first at a rate of 100°C / h to 15°C, then at a rate of 5°C / h to 5°C, and finally at a rate of 25°C / h to a final temperature of -20°C; the mixture after cooling and crystallization was subjected to solid-liquid separation, the solid phase was dried, and finally 5-hydroxymethylfurfural crystals were obtained.

[0042] The difference between Examples 30-34 is the amount of extractant added, as shown in Table 4. The purity of the 5-hydroxymethylfurfural crystals obtained in Examples 30-34 was determined by high performance liquid chromatography using the following method: the instrument was an Agilent 1260, the column type was Eclipse XDB-C18, the column temperature was 40°C, the UV detector, the mobile phase was 10% water and 90% methanol, the flow rate was 1 mL / min, and the detection wavelength was 283 nm. The results are shown in Table 4.

[0043] Table 4. Amount of methyl tert-butyl ether added and purity of 5-hydroxymethylfurfural product in Examples 30-34

[0044] Examples 35-41

[0045] A method for purifying 5-hydroxymethylfurfural, 50g of 5-hydroxymethylfurfural crude product obtained by dehydrating fructose is added into a beaker, 200g of water is added into the beaker, then 15g of activated carbon is added for stirring and adsorption, after the adsorption is completed, the filtrate is collected by filtration, then the filtrate is transferred into a separatory funnel, 400g of diethyl ether is added into the separatory funnel, after being shaken vigorously, the mixture is allowed to stand to separate into layers, the upper layer of 5-hydroxymethylfurfural organic solution is distilled to separate the solvent, a certain proportion is concentrated, then the solution is added into a crystallizer for cooling crystallization, the cooling rate adopts gradient cooling, first, the temperature is decreased to 15℃ at a rate of 100℃ / h, then the temperature is decreased to 5℃ at a rate of 5℃ / h, finally, the temperature is decreased to a final temperature of -20℃ at a rate of 25℃ / h, the mixture after the cooling crystallization is subjected to solid-liquid separation, the solid phase is dried, and finally, 5-hydroxymethylfurfural crystals are obtained.

[0046] The difference between examples 35-41 is that the proportion of the extractant concentration is different, as shown in Table 5. The purity of 5-hydroxymethylfurfural crystals obtained in examples 35-41 is detected by high performance liquid chromatography, and the specific method is as follows: the instrument is Agilent 1260, the column type is Eclipse XDB-C18, the column temperature is 40℃, the ultraviolet detector is used, the mobile phase is 10% water and 90% methanol, the flow rate is 1mL / min, and the detection wavelength is 283nm. The results are shown in Table 5.

[0047] Table 5. The proportion of the extractant concentration and the purity of 5-hydroxymethylfurfural product in examples 35-41

[0048] Examples 42-47

[0049] A method for purifying 5-hydroxymethylfurfural, 50g of 5-hydroxymethylfurfural crude product obtained by dehydrating fructose is added into a beaker, 200g of water is added into the beaker, then 15g of activated carbon is added for stirring and adsorption, after the adsorption is completed, the filtrate is collected by filtration, then the filtrate is transferred into a separatory funnel, 400g of diethyl ether is added into the separatory funnel, after being shaken vigorously, the mixture is allowed to stand to separate into layers, the upper layer of 5-hydroxymethylfurfural organic solution is distilled to separate the solvent, a certain proportion is concentrated, then the solution is added into a crystallizer for cooling crystallization, the cooling rate adopts gradient cooling, first, the temperature is decreased to 15℃ at a rate of 100℃ / h, then the temperature is decreased to 5℃ at a rate of 5℃ / h, finally, the temperature is decreased to a final temperature of -20℃ at a rate of 25℃ / h, the mixture after the cooling crystallization is subjected to solid-liquid separation, the solid phase is dried, and finally, 5-hydroxymethylfurfural crystals are obtained.

[0050] The difference between Examples 42-47 is the final temperature of crystallization, as shown in Table 6. The purity of the 5-hydroxymethylfurfural crystals obtained in Examples 42-47 was determined by high performance liquid chromatography using the following method: Agilent 1260 instrument, Eclipse XDB-C18 column, column temperature 40 °C, UV detector, mobile phase 10% water and 90% methanol, flow rate 1 mL / min, detection wavelength 283 nm. The results are shown in Table 6.

[0051] Table 6. Final temperature of crystallization and purity of 5-hydroxymethylfurfural product for Examples 42-47

[0052] Examples 48-52

[0053] A method for purifying 5-hydroxymethylfurfural, 50 g of 5-hydroxymethylfurfural crude product obtained by dehydrating fructose was added to a beaker, 150 g of water was added, then 15 g of activated carbon was added and stirred and adsorbed, after adsorption was complete, the filtrate was collected by filtration, then the filtrate was transferred to a separatory funnel, 300 g of methyl tert-butyl ether was added to the separatory funnel, after vigorous shaking, the layers were allowed to separate, the upper 5-hydroxymethylfurfural organic solution was distilled to separate the solvent, concentrated to 30%, then the solution was added to a crystallizer and cooled to crystallize, gradient cooling was used, after the crystallization reached a final temperature of -20 °C, solid-liquid separation was performed, the solid phase was dried, and finally 5-hydroxymethylfurfural crystals were obtained.

[0054] The difference between Examples 48-52 is the rate of temperature decrease during crystallization, as shown in Table 7. The purity of the 5-hydroxymethylfurfural crystals obtained in Examples 48-52 was determined by high performance liquid chromatography using the following method: Agilent 1260 instrument, Eclipse XDB-C18 column, column temperature 40 °C, UV detector, mobile phase 10% water and 90% methanol, flow rate 1 mL / min, detection wavelength 283 nm. The results are shown in Table 7.

[0055] Table 7. Gradient cooling crystallization rate and purity of 5-hydroxymethylfurfural product for Examples 48-52

[0056] Comparative Examples

[0057] Comparative Examples 1-8

[0058] A method for purifying 5-hydroxymethylfurfural, 50g of 5-hydroxymethylfurfural crude product obtained by dehydrating fructose is added into a beaker, 150g of water is added into the beaker, then 15g of activated carbon is added and stirred for adsorption, after the adsorption is completed, the filtrate is collected by filtration, then the filtrate is transferred into a separatory funnel, 300g of methyl tert-butyl ether is added into the separatory funnel, after being shaken vigorously, the upper layer of 5-hydroxymethylfurfural organic solution is separated by layering, the solvent is distilled and separated from the 5-hydroxymethylfurfural organic solution, the concentration is 30%, then the solution is added into a crystallizer for cooling crystallization, the cooling crystallization is performed at a constant rate, after reaching the final temperature of -20℃, solid-liquid separation is performed, the solid phase is dried, and finally 5-hydroxymethylfurfural crystals are obtained.

[0059] The difference between Comparative Examples 1-5 and Example 48 is that the cooling process is performed at a constant rate, and the difference between Comparative Examples 6-8 and Example 48 is that the gradient cooling crystallization rate is not within the preferred range, as shown in Table 8. The purity of the 5-hydroxymethylfurfural crystals obtained in Comparative Example 1 is detected by high performance liquid chromatography, and the specific method is as follows: the instrument is Agilent 1260, the column type is Eclipse XDB-C18, the column temperature is 40℃, the ultraviolet detector is used, the mobile phase is 10% water and 90% methanol, the flow rate is 1mL / min, and the detection wavelength is 283nm. The results are shown in Table 8.

[0060] Table 8. Cooling crystallization rate and 5-hydroxymethylfurfural product purity of Comparative Examples 1-8

[0061] As can be seen from the above table, when the cooling rate of Comparative Example 5 is 100℃ / h, HMF nucleates explosively during the crystallization process, the crystals agglomerate, and the impurities are severely encapsulated. Comparative Example 4 is 15℃ / h, and Comparative Example 3 is 10℃ / h. When the cooling rate continues to slow down, such as 6℃ / h in Comparative Example 2 and 2℃ / h in Comparative Example 1, although the purity of HMF can be improved, the time required for the entire crystallization process is longer, which is not conducive to scale-up production. The segmented cooling rate of Comparative Examples 6-8 is not within the preferred range, and the purification effect is decreased. Because the present application uses segmented cooling, on the one hand, it can shorten the crystallization time and save costs, and on the other hand, it can make the crystallization process within the metastable range, which is conducive to crystal growth and makes the purity of HMF higher.

[0062] The above description is only a preferred embodiment of the present application, and does not limit the present application in any form. Although the present application has been disclosed as above with a preferred embodiment, it is not intended to limit the present application. Any person skilled in the art can make some changes or modifications to the above disclosed technical content to obtain equivalent embodiments with equivalent changes, without departing from the technical solution of the present application. Any simple modification, equivalent change and modification of the above embodiments made in accordance with the technical essence of the present application are still within the scope of the technical solution of the present application.

Claims

1. A method for purifying 5-hydroxymethylfurfural, characterized by, The method comprises the following steps: (1) adding crude 5-hydroxymethylfurfural into water, adding activated carbon for adsorption, and separating the filtrate by filtration after the adsorption is completed; (2) adding an organic solvent into the filtrate obtained in step (1) for extraction, separating, and taking the organic phase for rotary evaporation concentration to obtain a crystallization solution; (3) performing temperature reduction crystallization on the crystallization solution obtained in step (2) to obtain purified 5-hydroxymethylfurfural.

2. A process for the purification of 5-hydroxymethylfurfural according to claim 1, characterized in that, The crude 5-hydroxymethylfurfural is obtained by dehydration of a sugar.

3. A method of purifying 5-hydroxymethylfurfural according to claim 1 or 2, c h a r a c t e r i z e d in that, The water is 0.5-10 times the weight of the 5-hydroxymethylfurfural.

4. The method of purifying 5-hydroxymethylfurfural according to claim 1, wherein, The activated carbon is 0.01-0.5 times the weight of the 5-hydroxymethylfurfural.

5. A method of purifying 5-hydroxymethylfurfural according to claim 1 or 4, characterized in that, The weight ratio of the organic solvent to water is (1-5):

1.

6. The method of purifying 5-hydroxymethylfurfural of claim 1, wherein, The organic solvent is selected from one or more of ethyl acetate, propyl acetate, butyl acetate, pentyl acetate, dichloromethane, chloroform, acetylacetone, cyclohexanone, methyl isobutyl ketone, diethyl ether, isopropyl ether, methyl tert-butyl ether, tetrahydrofuran, and 2-methyltetrahydrofuran.

7. A method of purifying 5-hydroxymethylfurfural according to claim 1 or 6, characterized in that, The mass ratio of rotary evaporation concentration is 20-70%.

8. The method of purifying 5-hydroxymethylfurfural of claim 1, wherein, The final temperature of the temperature reduction crystallization is -30 to -5℃.

9. A method of purifying 5-hydroxymethylfurfural according to claim 1 or 8, characterized in that, The temperature reduction crystallization adopts gradient temperature reduction, specifically: reducing to 14-16℃ at a rate of 50-150℃ / h, reducing to 4-6℃ at a rate of 2-10℃ / h, and reducing to -30 to -5℃ at a rate of 10-30℃ / h.

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