Preparation method of 2, 5-furandicarboxylic acid

Abstract

The invention provides a preparation method of 2, 5-furandicarboxylic acid, which is characterized in that 5-hydroxymethylfurfural reacts under the action of an oxidizing agent and an ether solvent in an oxygen atmosphere to obtain the 2, 5-furandicarboxylic acid. According to the method, the furandicarboxylic acid is prepared from the 5-hydroxymethylfurfural serving as a raw material through one-step oxidation under the action of the oxidizing agent and the ether solvent, and the initiator is introduced, so that the reaction temperature is reduced, self-polymerization of monomers is avoided, and the reaction yield and selectivity are improved; the reaction system also shortens the reaction time, avoids the use of metals in the reaction, has mild reaction conditions, does not need high temperature and high pressure, increases the reaction safety, simplifies the reaction conditions, and is more suitable for industrial production.

Description

Technical Field

[0001] The invention belongs to the field of organic synthesis, and specifically relates to a method for preparing 2,5-furandicarboxylic acid. Background Art

[0002] With the increasing shortage of fossil energy and the expansion of energy demand, the utilization of renewable biomass energy has attracted more and more attention. Phthalates are commonly used plasticizers in the plastic processing process and are widely used in plastic containers, packaging materials, medical devices, children's toys and other products. This type of substance is an environmental endocrine disruptor, and also has varying degrees of hepatotoxicity and reproductive toxicity, and even has the risk of carcinogenicity and teratogenicity. The European Union and many countries are restricting the use of plasticizers in plastics. Studies have found that 2,5-furandicarboxylic acid dialkyl ester can be added to plastics as a plasticizer and can be used in fibers, films, packaging materials and engineering plastics. It has the excellent properties of low carbon, environmental protection and degradability. It is one of the best substitutes for petroleum-based raw materials terephthalic acid polyester in the future and has important application potential value. Furandicarboxylic acid is an important intermediate for the synthesis of 2,5-furandicarboxylic acid dialkyl ester, and the study of its preparation method is of great significance.

[0003] At present, there are many studies on the synthesis of 2,5-furandicarboxylic acid, but most research schemes have complex catalysts or harsh reaction conditions, require high temperature or high pressure, have low safety, and are relatively costly. Some of the precious metal catalysts used are relatively expensive, and the products obtained by metal system catalysis will have metal residues that are difficult to remove, which is not conducive to subsequent bio-based applications.

[0004] Publication No. CN116265448A provides a method for preparing furandicarboxylic acid using furan dicarboxylic acid and a method for preparing dimethyl furandicarboxylate. The method for preparing furandicarboxylic acid using furan dicarboxylic acid comprises reacting furfural and CO2 under the condition of a catalyst to generate furandicarboxylic acid; wherein the catalyst is a solid base supported by a porous organic polymer; and furandicarboxylic acid is attached to the solid base. The catalyst of the method needs to be prepared by itself, which is relatively complicated and not conducive to industrial production; in addition, the reaction also requires a high temperature of 260°C, and the reaction conditions are harsh.

[0005] Publication No. DE102016118154B3 provides a method for producing 2,5-FDCA, a method for producing 2,5-FDCA (2,5-furandicarboxylic acid) from 5-HMF (5-(hydroxymethyl)furfural), wherein an enzyme catalyst having HMF / furfural oxidoreductase activity is contacted with process water derived from a hydrothermal carbonization process, the process water used is pretreated to reduce the content of HMF dimers contained in the process water, and the content of HMF dimers is reduced by filtering the process water at 100°C.

[0006] Publication No. CN107848997B provides a method for preparing 2,5-furandicarboxylic acid and its esters, and a method for preparing 2,5-furandicarboxylic acid and its dimethyl ester from 5-hydroxymethylfurfural and humin, comprising: a) oxidizing a raw material containing hydroxymethylfurfural and humin to produce a mixture containing crude 2,5-furandicarboxylic acid containing humin; b) separating the mixture to obtain a solid 2,5-furandicarboxylic acid / humin composition. The method requires a high pressure of 450 psig and a high temperature of 200°C, has high requirements on the reactor, and has very harsh reaction conditions.

[0007] In summary, developing a method for preparing 2,5-furandicarboxylic acid with high conversion rate, convenient industrial production and safe reaction has become an urgent problem to be solved. Summary of the invention

[0008] In view of the shortcomings of the prior art, the object of the present invention is to provide a method for preparing 2,5-furandicarboxylic acid. The method provided by the present invention avoids the use of metals in the reaction, has mild reaction conditions, does not require high temperature and high pressure, increases reaction safety, simplifies reaction conditions, and is more suitable for industrial production.

[0009] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0010] A method for preparing 2,5-furandicarboxylic acid comprises the following steps: in an oxygen atmosphere, 5-hydroxymethylfurfural is reacted under the action of an oxidant and an ether solvent to obtain 2,5-furandicarboxylic acid.

[0011] The oxygen atmosphere in the present invention can be a common oxygen bag or oxygen ball, and the oxygen pressure is close to the standard atmospheric pressure, and there is no need to deliberately pressurize it.

[0012] Specifically, the ether solvent is at least one selected from ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, 1,4-dioxane, diisopropyl ether, ethyl ether and anisole.

[0013] Specifically, the oxidant is hydrogen peroxide.

[0014] Specifically, the molar ratio of the 5-hydroxymethylfurfural, the oxidant and the ether solvent is 1:(2-5):(7-10).

[0015] Specifically, an initiator needs to be added to the reaction, and the initiator is at least one selected from azobisisobutyronitrile, BPO, potassium persulfate and tert-butyl peroxide.

[0016] Preferably, the molar ratio of the 5-hydroxymethylfurfural to the initiator is 1:(0.1-0.3).

[0017] Specifically, the reaction temperature is 40-80°C; preferably, the reaction temperature can be 40°C, 50°C, 60°C, 70°C or 80°C, etc., but is not limited to the above-listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0018] Preferably, the reaction temperature is 60-70°C; more preferably, the reaction temperature can be 60°C, 61°C, 62°C, 63°C, 64°C, 65°C, 66°C, 67°C, 68°C, 69°C or 70°C, etc., but is not limited to the values ​​listed above, and other values ​​not listed within the above numerical range are also applicable.

[0019] Specifically, the reaction time is 0.5 to 2 h; preferably, the reaction time can be 0.5 h, 0.7 h, 0.9 h, 1 h, 1.2 h, 1.4 h, 1.6 h, 1.8 h or 2 h, but is not limited to the above-listed values, and other unlisted values ​​within the above numerical range are also applicable.

[0020] Specifically, the reaction needs to be carried out under natural light. The light can be natural light or lamp light, and any light condition that can achieve the reaction is acceptable.

[0021] Specifically, the reaction also requires post-treatment, including the following steps: after the reaction is completed, water is added for extraction, the aqueous phase is subjected to reduced pressure distillation to obtain a brown solid, which is refined to obtain a white solid, and filtered to obtain the 2,5-furandicarboxylic acid.

[0022] Preferably, the brown solid obtained by the reaction is refined by adding about 5 times by weight of methanol and about 0.5 times by weight of activated carbon, heating to 55-65°C, stirring for 1-3h, and then filtering to obtain a colorless solution, and removing the solvent by reduced pressure distillation to obtain a white solid, adding about 4 times by weight of ethanol, heating to 60-80°C, stirring to dissolve, and then cooling to about 5°C for 5-7h to precipitate a large amount of white solid, i.e., 2,5-furandicarboxylic acid.

[0023] Compared with the prior art, the present invention provides a method for preparing 2,5-furandicarboxylic acid, which has the following characteristics:

[0024] Beneficial effects:

[0025] (1) The present invention uses 5-hydroxymethylfurfural as a raw material, and prepares furandicarboxylic acid by oxidation in a single step under the action of an oxidant and an ether solvent, and then introduces an initiator to reduce the reaction temperature, avoid self-polymerization of the monomer, and improve the reaction yield and selectivity;

[0026] (2) The reaction system of the present invention also shortens the reaction time, avoids the use of metals in the reaction, has mild reaction conditions, does not require high temperature and high pressure, increases reaction safety, simplifies reaction conditions, and is more suitable for industrial production. DETAILED DESCRIPTION

[0027] In order to further explain the technical means and effects adopted by the present invention, the technical solution of the present invention is further described below in conjunction with the preferred embodiments of the present invention, but the present invention is not limited to the scope of the embodiments.

[0028] Example 1

[0029] The present embodiment provides a method for preparing 2,5-furandicarboxylic acid, comprising the following steps: in a reaction bottle, dipropylene glycol dimethyl ether (113.5 g, 0.7 mol, 162.13 g / mol), 5-hydroxymethylfurfural (12.6 g, 0.1 mol, 126.11 g / mol), hydrogen peroxide (37 g, 0.3 mol) and azobisisobutyronitrile (0.32 g, 0.02 mol) are added in sequence, mixed evenly, and then the air is replaced with an oxygen atmosphere, and the mixture is stirred and heated to 60° C. under natural light for reaction for 1 hour, and the reaction is monitored by TLC until the conversion of the raw materials is completed. After the reaction was completed, 100 ml of water was added and extracted three times. After separating the water layer, the water was distilled off under reduced pressure to obtain 16.8 g of a brown solid. The brown solid obtained by the reaction was added with 5 times the weight ratio of methanol and 0.5 times the weight ratio of activated carbon. The temperature was raised to 60°C and stirred for 2 hours, and then filtered to obtain a colorless solution. After removing the solvent by distillation under reduced pressure, a white solid was obtained. 4 times the weight ratio of ethanol was added, the temperature was raised to 70°C and stirred to dissolve, and then the temperature was lowered to 5°C and kept warm for 6 hours. A large amount of white solid precipitated, and 15.3 g of 2,5-furandicarboxylic acid product was obtained after filtration. The reaction yield was 98% and the purity was 99.9%.

[0030] Example 2

[0031] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that ethylene glycol dimethyl ether (63.1 g, 0.7 mol, 90.121 g / mol) is added to the reaction bottle, and finally 14.7 g of 2,5-furandicarboxylic acid product is obtained, with a reaction yield of 94% and a purity of 99.8%.

[0032] Example 3

[0033] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that diethylene glycol dimethyl ether (93.9 g, 0.7 mol, 134.17 g / mol) is added to the reaction bottle, and finally 15.1 g of 2,5-furandicarboxylic acid product is obtained, with a reaction yield of 97% and a purity of 99.9%.

[0034] Example 4

[0035] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that 1,4-dioxane (61.7 g, 0.7 mol, 88.105 g / mol) is added to the reaction bottle, and finally 13.3 g of 2,5-furandicarboxylic acid product is obtained, with a reaction yield of 85% and a purity of 99.9%.

[0036] Example 5

[0037] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that hydrogen peroxide (24.5 g, 0.2 mol) is added to finally obtain 13.3 g of 2,5-furandicarboxylic acid product, with a reaction yield of 85% and a purity of 99.9%.

[0038] Example 6

[0039] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that hydrogen peroxide (61.5 g, 0.5 mol) is added to finally obtain 14.2 g of 2,5-furandicarboxylic acid product, with a reaction yield of 91% and a purity of 99.8%.

[0040] Example 7

[0041] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that dipropylene glycol dimethyl ether (129.7 g, 0.8 mol, 162.13 g / mol) is added to finally obtain 15.8 g of 2,5-furandicarboxylic acid product, with a reaction yield of 95% and a purity of 99.8%.

[0042] Example 8

[0043] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that dipropylene glycol dimethyl ether (162.1 g, 1.0 mol, 162.13 g / mol) is added to finally obtain 14.2 g of 2,5-furandicarboxylic acid product, with a reaction yield of 91% and a purity of 99.9%.

[0044] Example 9

[0045] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that azobisisobutyronitrile (0.16 g, 0.01 mol) is added to finally obtain 14.1 g of 2,5-furandicarboxylic acid product, with a reaction yield of 90% and a purity of 99.9%.

[0046] Example 10

[0047] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that azobisisobutyronitrile (0.48 g, 0.03 mol) is added to finally obtain 14.8 g of 2,5-furandicarboxylic acid product, with a reaction yield of 95% and a purity of 99.9%.

[0048] Embodiment 11

[0049] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that the mixture is stirred and heated to 40° C. under natural light for 2 hours to finally obtain 11.4 g of 2,5-furandicarboxylic acid product with a reaction yield of 73% and a purity of 99.9%.

[0050] Example 12

[0051] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that the temperature is raised to 70° C. under natural light for reaction for 1 hour, and finally 15.1 g of 2,5-furandicarboxylic acid product is obtained, with a reaction yield of 97% and a purity of 99.9%.

[0052] Example 13

[0053] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that the mixture is stirred and heated to 80° C. for reaction for 1 hour under natural light, and finally 14.2 g of 2,5-furandicarboxylic acid product is obtained, with a reaction yield of 91% and a purity of 99.8%.

[0054] Embodiment 14

[0055] This embodiment provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that an initiator potassium persulfate (5.4 g, 0.02 mol, 270.322 g / mol) is added to finally obtain 13.6 g of 2,5-furandicarboxylic acid product, with a reaction yield of 87% and a purity of 99.9%.

[0056] Comparative Example 1

[0057] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that diisopropyl ether (71.5 g, 0.7 mol, 102.175 g / mol) is added to the reaction flask, and finally 4.2 g of 2,5-furandicarboxylic acid product is obtained, and the reaction yield is 27%.

[0058] Comparative Example 2

[0059] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that ether (51.9 g, 0.7 mol, 74.12 g / mol) is added to the reaction flask, and finally 2.8 g of 2,5-furandicarboxylic acid product is obtained, and the reaction yield is 18%.

[0060] Comparative Example 3

[0061] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that anisole (75.6 g, 0.7 mol, 108.138 g / mol) is added to the reaction flask, and finally 0.8 g of 2,5-furandicarboxylic acid product is obtained, and the reaction yield is 5%.

[0062] Comparative Example 4

[0063] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that an initiator BPO (4.8 g, 0.02 mol, 242.23 g / mol) is added to finally obtain 3.9 g of 2,5-furandicarboxylic acid product, with a reaction yield of 25% and a purity of 90%.

[0064] Comparative Example 5

[0065] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that acetonitrile solvent (80 g, 1.95 mol) is added, but ultimately no reaction occurs, and no target product is generated.

[0066] Comparative Example 6

[0067] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that no hydrogen peroxide is added, and the final reaction is relatively messy, generating numerous polymerization by-products and no target product.

[0068] Comparative Example 7

[0069] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that no initiator is added, and a self-polymerization product is finally generated without generating a target product.

[0070] Comparative Example 8

[0071] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that the reaction temperature is 120° C., and eventually a large amount of tarry by-products are produced due to the excessively high temperature.

[0072] Comparative Example 9

[0073] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that the reaction temperature is 30° C., and ultimately no reaction occurs, and no target product is generated.

[0074] Comparative Example 10

[0075] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that the reaction time is 10 hours, and 13.9 g of 2,5-furandicarboxylic acid product is finally obtained, with a reaction yield of 89%.

[0076] Comparative Example 11

[0077] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that dipropylene glycol dimethyl ether (64.9 g, 0.4 mol, 162.13 g / mol) is added to finally obtain 2.34 g of 2,5-furandicarboxylic acid product, and the reaction yield is 15%.

[0078] Comparative Example 12

[0079] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that hydrogen peroxide (12.3 g, 0.1 mol) is added to finally obtain 4.7 g of 2,5-furandicarboxylic acid product, with a reaction yield of 30%.

[0080] Comparative Example 13

[0081] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that hydrogen peroxide (74 g, 0.6 mol) is added to finally obtain 15.1 g of 2,5-furandicarboxylic acid product, with a reaction yield of 96.7% and a purity of 93%. Although the yield is basically the same as that of Example 1, there is too much hydrogen peroxide remaining, and the post-processing risk is high.

[0082] Comparative Example 14

[0083] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that azobisisobutyronitrile (0.08 g, 0.005 mol) is added to finally obtain 2.5 g of 2,5-furandicarboxylic acid product, and the reaction yield is 16%.

[0084] Comparative Example 15

[0085] This comparative example provides a method for preparing 2,5-furandicarboxylic acid, which is basically the same as Example 1, except that azobisisobutyronitrile (0.64 g, 0.04 mol) is added to finally obtain 15.2 g of 2,5-furandicarboxylic acid product, with a reaction yield of 97.4% and a purity of 99.7%. Although the yield is basically the same as that of Example 1, it will cause a waste of raw materials.

[0086] The applicant declares that the present invention illustrates a method for preparing 2,5-furandicarboxylic acid of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned embodiments, that is, it does not mean that the present invention must rely on the above-mentioned embodiments to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of various raw materials of the product of the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

[0087] The preferred embodiments of the present invention are described in detail above. However, the present invention is not limited to the specific details in the above embodiments. Within the technical concept of the present invention, a variety of simple modifications can be made to the technical solution of the present invention, and these simple modifications all belong to the protection scope of the present invention.

[0088] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present invention will not further describe various possible combinations.

Claims

1. A method for preparing 2,5-furandicarboxylic acid, characterized in that: Under an oxygen atmosphere, 5-hydroxymethylfurfural reacts with an oxidant and an ether solvent to obtain 2,5-furandicarboxylic acid.

2. The preparation method according to claim 1, characterized in that: The ether solvent is at least one selected from ethylene glycol dimethyl ether, diethylene glycol dimethyl ether, dipropylene glycol dimethyl ether, 1,4-dioxane, diisopropyl ether, ethyl ether and anisole.

3. The preparation method according to claim 1, characterized in that: The oxidant is hydrogen peroxide.

4. The preparation method according to claim 1, characterized in that: The molar ratio of the 5-hydroxymethylfurfural, the oxidant and the ether solvent is 1:(2-5):(7-10).

5. The preparation method according to claim 1, characterized in that: An initiator needs to be added in the reaction, and the initiator is at least one selected from azobisisobutyronitrile, BPO, potassium persulfate and tert-butyl peroxide.

6. The preparation method according to claim 5, characterized in that: The molar ratio of the 5-hydroxymethylfurfural to the initiator is 1:(0.1-0.3).

7. The preparation method according to claim 1, characterized in that: The reaction temperature is 40 to 80°C; Preferably, the reaction temperature is 60-70°C.

8. The preparation method according to claim 1, characterized in that: The reaction time is 0.5 to 2 hours.

9. The preparation method according to claim 1, characterized in that: The reaction needs to be carried out under natural light.

10. The preparation method according to claim 1, characterized in that: The reaction also requires post-treatment, including the following steps: after the reaction is completed, water is added for extraction, the aqueous phase is subjected to reduced pressure distillation to obtain a brown solid, which is refined to obtain a white solid, which is filtered to obtain the 2,5-furandicarboxylic acid.