Preparation method of 2, 5-furandicarboxylic acid

Abstract

The invention provides a preparation method of 2, 5-furandicarboxylic acid, and relates to the technical field of organic synthesis. The invention discloses a preparation method of 2, 5-furandicarboxylic acid, which comprises the following step: carrying out oxidation reaction on 5-hydroxymethylfurfural, piperidine nitrogen oxide, bromide, acid and halogenated isocyanuric acid in a reaction solvent to obtain the 2, 5-furandicarboxylic acid. The preparation method of the 2, 5-furandicarboxylic acid is simple and effective, the post-treatment is simple, and the 2, 5-furandicarboxylic acid with higher yield and purity can be obtained.

Description

Technical Field

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

[0002] 2,5-furandicarboxylic acid (FDCA) is an important platform compound derived from biomass resources. More than 100 derivatives make it have very important application prospects and can be used as a monomer for synthesizing bio-based polymers. 2,5-furandicarboxylic acid has a similar structure to terephthalic acid, but its furan ring structure is easier to degrade in nature than the benzene ring. Therefore, 2,5-furandicarboxylic acid can be used to replace terephthalic acid to synthesize more environmentally friendly polymer polyester materials.

[0003] At present, the research and preparation of 2,5-furandicarboxylic acid usually uses 5-hydroxymethylfurfural (HMF) as a raw material and noble metals as catalysts to catalytically oxidize it under alkaline conditions. After the reaction, the reaction liquid needs to be acidified, which is cumbersome to operate and produces a lot of three wastes. For example, Document 1 discloses a method for preparing FDCA by thermal catalytic oxidation, using HMF as a substrate, silver-palladium / carbon bimetallic as a catalyst, and oxygen as an oxygen source to prepare the product under mild conditions. However, the cost of noble metal catalysts is high, the production process is complex and uncontrollable, which limits their large-scale application.

[0004] Document 1: CN115710242A. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a method for preparing 2,5-furandicarboxylic acid.

[0006] The technical solution of the present invention is as follows:

[0007] A method for preparing 2,5-furandicarboxylic acid comprises the following steps: 5-hydroxymethylfurfural, piperidine nitrogen oxide, bromide salt, acid and halogenated isocyanuric acid are subjected to oxidation reaction in a reaction solvent to obtain the 2,5-furandicarboxylic acid.

[0008] Preferably, the reaction solvent is selected from water, an organic solvent or a mixed solvent consisting of water and an organic solvent.

[0009] More preferably, the solubility of the organic solvent in water at 20° C. is not less than 5 g / 100 ml.

[0010] Preferably, the piperidine N-oxide is selected from 2,2,6,6-tetramethylpiperidine N-oxide and its derivatives.

[0011] Preferably, the bromide salt is selected from one or a combination of two or more of sodium bromide, potassium bromide, lithium bromide, calcium bromide, copper bromide, zinc bromide, nickel bromide and magnesium bromide.

[0012] Preferably, the pH of a 1 mol / L aqueous solution of the acid is not higher than 3.

[0013] Preferably, the halogenated isocyanuric acid is selected from one or a combination of two or more of bromoisocyanuric acid, dichloroisocyanuric acid, trichloroisocyanuric acid, chloroisocyanuric acid and chlorobromoisocyanuric acid.

[0014] Preferably, the molar ratio of the 5-hydroxymethylfurfural, the piperidine nitrogen oxide and the halogenated isocyanuric acid is 1:(0.001-0.04):(0.5-5).

[0015] Preferably, the weight ratio of the reaction solvent, the 5-hydroxymethylfurfural, the bromide salt and the acid is (10-100):1:(0.01-1):(0.001-0.1).

[0016] Preferably, the oxidation reaction temperature is 15-70°C and the time is 0.5-5h.

[0017] The beneficial effects of the present invention are:

[0018] (1) The present invention uses piperidine nitrogen oxide as a catalyst and oxidant, halogenated isocyanuric acid as an oxidant, and adds bromide salt as a co-catalyst to achieve efficient oxidation and conversion of HMF in an acidic environment, and obtains FDCA with high purity after simple post-treatment. The method of the present invention has low catalyst cost, no alkaline substances are added, the discharge of high-salt wastewater is reduced, the production cost is greatly reduced, the process is simpler and more economical, and has broad market application prospects.

[0019] (2) The present invention uses bromide salt as a promoter of halogenated isocyanuric acid, which can significantly improve the efficiency of the oxidation conversion of the raw material HMF into FDCA, thereby increasing the conversion rate of HMF and the yield of FDCA. DETAILED DESCRIPTION

[0020] The technical solution of the present invention is further illustrated and described below through specific implementation methods.

[0021] In order to make the preparation method of FDCA simpler and more efficient, the present invention provides a preparation method of 2,5-furandicarboxylic acid, wherein 5-hydroxymethylfurfural, piperidine nitrogen oxide, bromide salt, acid and halogenated isocyanuric acid are subjected to oxidation reaction in a reaction solvent to obtain 2,5-furandicarboxylic acid.

[0022] In the FDCA preparation method of the present invention, HMF is used as a raw material, piperidine nitrogen oxide is used as a catalyst, bromide salt is used as a co-catalyst, and halogenated isocyanuric acid is used as an oxidant. An oxidation reaction occurs in an acidic environment, and HMF is efficiently converted into FDCA. The post-treatment after the oxidation reaction is relatively simple. After the oxidation reaction product is cooled, separated, washed and dried, the FDCA product can be obtained. The molar yield of the FDCA product can reach more than 85%, and the purity can reach more than 96%.

[0023] In a preferred embodiment of the present invention, the reaction solvent is selected from water, an organic solvent or a mixed solvent consisting of water and an organic solvent. More preferably, the reaction solvent is selected from a mixed solvent consisting of water and an organic solvent, and the weight ratio of water to the organic solvent can be 1:1-50. A certain amount of water in the reaction solvent is more conducive to the acid generating hydrogen ions and making the piperidine nitrogen oxide have higher oxidation and catalytic properties.

[0024] In a more preferred embodiment of the present invention, the solubility of the organic solvent in water at 20° C. is not less than 5 g / 100 ml. For example, the organic solvent may be methyl isobutyl ketone, ethyl acetate, acetonitrile, acetone, DMSO, DMF, DMAc, methyl ethyl ketone, 1,4-dioxane, methyl pyrrolidone, and the like.

[0025] In a preferred embodiment of the present invention, the piperidine nitrogen oxide is selected from 2,2,6,6-tetramethylpiperidine nitrogen oxide and its derivatives. 2,2,6,6-tetramethylpiperidine nitrogen oxide TEMPO is a common piperidine nitrogen oxide. The piperidine nitrogen oxide in the present invention can also be a 2,2,6,6-tetramethylpiperidine nitrogen oxide containing a substituent at the 4-position, such as 4-hydroxy-2,2,6,6-tetramethylpiperidine nitrogen oxide, 4-amino-2,2,6,6-tetramethylpiperidine nitrogen oxide, 4-methoxy-2,2,6,6-tetramethylpiperidine nitrogen oxide, 4-nitrile-2,2,6,6-tetramethylpiperidine nitrogen oxide, 4-acetamido-2,2,6,6-tetramethylpiperidine nitrogen oxide, 4-formyl-2,2,6,6-tetramethylpiperidine nitrogen oxide, etc.

[0026] Halogenated isocyanuric acid, such as chloroisocyanuric acid, decomposes into isocyanuric acid and hypochlorous acid in water. If bromide ions are present in water, bromide ions can react with hypochlorous acid to generate hypobromous acid with better oxidizability. In the present invention, bromide salts are used as co-catalysts to improve the oxidizing properties of halogenated isocyanuric acid, especially chloroisocyanuric acid, and improve the oxidation effect on HMF, and the conversion rate of HMF is higher. In a preferred embodiment of the present invention, the bromide salt is selected from one or a combination of two or more of sodium bromide, potassium bromide, lithium bromide, calcium bromide, copper bromide, zinc bromide, nickel bromide and magnesium bromide. Considering the cost dimension, the bromide salt is more preferably sodium bromide.

[0027] In a preferred embodiment of the present invention, the pH of a 1 mol / L aqueous solution corresponding to the acid is not higher than 3. In the present invention, the acidity of the acid cannot be too low, otherwise less hydrogen ions are generated, which is not conducive to promoting the oxidation of piperidine nitrogen oxides and the performance of catalytic performance. The acid in the present invention can be an organic acid or an inorganic acid. For example, the organic acid can be acetic acid, malic acid, oxalic acid, propionic acid, benzenesulfonic acid, 1-butanesulfonic acid, etc., and the inorganic acid can be sulfuric acid, hydrochloric acid, phosphoric acid, nitric acid, hydrobromic acid, etc.

[0028] The present invention adopts halogenated isocyanuric acid as the main oxidant, which can be decomposed under acidic conditions, and the decomposition product is soluble in an organic solvent, which is conducive to the purification and separation of the product FDCA, and the post-processing after the reaction is simpler, and the speed of the halogenated isocyanuric acid decomposition and release of hypohalous acid is more stable, which has a stabilizing effect on the oxidation reaction process. If sodium hypochlorite and / or hydrogen peroxide are used as oxidants to replace halogenated isocyanuric acid, it is necessary to react under alkaline conditions, and the reaction needs to be adjusted to precipitate FDCA after the reaction, which will produce high-salt wastewater, which is not conducive to the post-processing operation after the reaction and the purification of the product. If sodium hypochlorite, hydrogen peroxide, etc. are used as oxidants, and under acidic conditions, the oxidation performance will be poor, which is not conducive to the oxidation of HMF and conversion into FDCA. In a preferred embodiment of the present invention, the halogenated isocyanuric acid is selected from one or two or more combinations of bromoisocyanuric acid, dichloroisocyanuric acid, trichloroisocyanuric acid, chloroisocyanuric acid and chlorobromoisocyanuric acid. From the perspective of cost and performance, the halogenated isocyanuric acid is more preferably dichloroisocyanuric acid, trichloroisocyanuric acid and chlorobromoisocyanuric acid.

[0029] In a preferred embodiment of the present invention, the molar ratio of 5-hydroxymethylfurfural, piperidine nitrogen oxide and halogenated isocyanuric acid is 1:(0.001-0.04):(0.5-5). For example, the molar ratio of 5-hydroxymethylfurfural, piperidine nitrogen oxide and halogenated isocyanuric acid can be any value in 1:0.001:1, 1:0.005:1, 1:0.01:1, 1:0.02:1, 1:0.04:1, 1:0.01:0.5, 1:0.01:2, 1:0.01:5, 1:0.02:1, 1:0.02:0.5, 1:0.005:2, 1:0.005:0.5, 1:0.02:3, 1:0.02:5, etc., or any value therebetween, without particular limitation. More preferably, the molar ratio of 5-hydroxymethylfurfural to piperidine nitrogen oxide can be 1:0.003-0.02, for example, the molar ratio can be any value in 1:0.003, 1:0.005, 1:0.007, 1:0.008, 1:0.01, 1:0.012, 1:0.015, 1:0.017, 1:0.02, etc. or any value therebetween, without particular limitation. More preferably, the molar ratio of 5-hydroxymethylfurfural to halogenated isocyanuric acid can be 1:0.8-3, for example, the molar ratio can be any value in 1:0.8, 1:1, 1:1.2, 1:1.5, 1:1.8, 1:2, 1:2.2, 1:2.5, 1:2.7, 1:3, etc. or any value therebetween, without particular limitation.

[0030] In a preferred embodiment of the present invention, the weight ratio of the reaction solvent, 5-hydroxymethylfurfural, bromide salt and acid is (10-100):1:(0.01-1):(0.001-0.1). For example, the weight ratio of the reaction solvent, 5-hydroxymethylfurfural, bromide salt and acid can be 10:1:0.1:0.01, 30:1:0.1:0.01, 60:1:0.1:0.01, 100:1:0.1:0.01, 30:1:0.01:0.01, 30:1:0.05:0.01, 30:1:0.3:0.01, 30:1:0.5:0.01, 30:1:0.7:0.01, 30:1:1:0.01, 50:1:0.05:0.01, 50:1:0.2:0.01 , 30:1:0.01:0.001, 30:1:0.01:0.005, 30:1:0.01:0.01, 30:1:0.01:0.03, 30:1:0.01:0.05, 30:1:0.01:0.01, 50:1:0.1:0.001, 50:1:0.1:0.005, 50:1:0.1:0.01, 50:1:0.1:0.03, 50:1:0.1:0.05, 50:1:0.1:0.01, etc., or any value in between, without any particular limitation. More preferably, the weight ratio of 5-hydroxymethylfurfural and bromide salt can be 1:0.05-0.5. For example, the weight ratio can be any value among 1:0.05, 1:0.1, 1:0.15, 1:0.2, 1:0.25, 1:0.3, 1:0.35, 1:0.4, 1:0.45, 1:0.5, etc. or any value in between, without special limitation. More preferably, the weight ratio of 5-hydroxymethylfurfural and acid can be 1:0.005-0.07. For example, the weight ratio can be any value among 1:0.005, 1:0.01, 1:0.015, 1:0.02, 1:0.025, 1:0.03, 1:0.035, 1:0.04, 1:0.045, 1:0.05, 1:0.055, 1:0.06, 1:0.065, 1:0.07, etc. or any value in between, without particular limitation.

[0031] In a preferred embodiment of the present invention, the temperature of the oxidation reaction is 15-70°C and the time is 0.5-5h. In general, the lower the temperature of the oxidation reaction, the longer the reaction time required, and vice versa. For example, the oxidation reaction can be 20°C×5h, 30°C×4h, 40°C×3h, 45°C×2.5h, 50°C×1h, 70°C×0.5h, etc., without special restrictions.

[0032] In the present invention, the catalyst TEMPO, the oxidant halogenated isocyanuric acid and its decomposition products are all soluble in organic solvents, while the product FDCA is insoluble in organic solvents, water, and a mixed solvent composed of water and organic solvents, so the product FDCA can be easily separated from other substances in the reaction product solution, and a higher product purity is obtained, the process operation is simple, the production material cost is low, and it is conducive to industrial production. Specifically, the post-treatment after the oxidation reaction can be as follows: after the oxidation reaction, the reaction solution is cooled to room temperature, the reaction product is centrifuged and the solid is collected, the solid is washed with water 3 times, and the FDCA product is obtained after drying. The yield of FDCA can be calculated by the input HMF raw material and the collected FDCA product, and the purity of the FDCA product can be obtained by high performance liquid chromatography HPLC or gas chromatography GC test.

[0033] The technical solution of the present invention is further described and illustrated according to various embodiments below. Unless otherwise specified, the parts described in the following embodiments are parts by weight.

[0034] Example 1

[0035] HMF (12.61 g, 100 mmol), TEMPO (0.156 g, 1 mmol), trichloroisocyanuric acid (23.24 g, 100 mmol) and sodium bromide (1.023 g, 10 mmol) were added to a reaction flask containing 50 ml of water and 300 ml of methyl isobutyl ketone as a mixed solvent, and the mixture was stirred to dissolve. Then 0.4 g of acetic acid was added, and the mixture was stirred and heated to 50° C. for 1 h. After the reaction was completed, the mixture was quickly cooled to room temperature. The reaction product was centrifuged at 3000 rpm for 30 min, and the solid was collected. The solid was washed three times with 100 ml of water and freeze-dried in vacuo to obtain a white FDCA solid.

[0036] The purity of the FDCA solid was measured by HPLC to be 98.2%. The molar yield of FDCA was calculated to be 87.2% by weighing the FDCA solid.

[0037] Example 2

[0038] The difference between this embodiment and embodiment 1 is that the trichloroisocyanuric acid in embodiment 1 is adjusted from 100 mmol to 150 mmol. The other steps remain unchanged.

[0039] The purity of the FDCA solid was measured by HPLC to be 97.8%. The molar yield of FDCA was calculated to be 87.0% by weighing the FDCA solid.

[0040] Example 3

[0041] The difference between this example and Example 1 is that the HMF in Example 1 is adjusted from 100 mmol to 50 mmol. The other steps remain unchanged.

[0042] The purity of the FDCA solid was measured by HPLC to be 98.4%. The molar yield of FDCA was calculated to be 88.5% by weighing the FDCA solid.

[0043] Example 4

[0044] The difference between this embodiment and embodiment 1 is that the methyl isobutyl ketone in embodiment 1 is replaced by an equal weight of ethyl acetate. The other steps remain unchanged.

[0045] The purity of the FDCA solid was measured by HPLC to be 98.3%. The molar yield of FDCA was calculated to be 85.6% by weighing the FDCA solid.

[0046] Example 5

[0047] The difference between this embodiment and embodiment 1 is that the methyl isobutyl ketone in embodiment 1 is adjusted from 300 ml to 600 ml. The other steps remain unchanged.

[0048] The purity of the FDCA solid was measured by HPLC to be 98.5%. The molar yield of FDCA was calculated by weighing the FDCA solid to be 90.1%.

[0049] Example 6

[0050] The difference between this embodiment and embodiment 1 is that in embodiment 1, the mixed solvent is replaced by an equal weight of methyl isobutyl ketone. The other steps remain unchanged.

[0051] The purity of the FDCA solid was measured by HPLC to be 90.7%. The molar yield of FDCA was calculated to be 80.4% by weighing the FDCA solid.

[0052] Comparative Example 1

[0053] The difference between this comparative example and Example 1 is that sodium bromide is not added in Example 1. The remaining steps remain unchanged.

[0054] The purity of the FDCA solid was measured by HPLC to be 98.1%. The molar yield of FDCA was calculated to be 65.8% by weighing the FDCA solid.

[0055] Comparative Example 2

[0056] The difference between this comparative example and Example 1 is that the sodium bromide in Example 1 is replaced by an equal weight of sodium chloride. The remaining steps remain unchanged.

[0057] The purity of the FDCA solid was measured by HPLC to be 97.9%. The molar yield of FDCA was calculated to be 63.5% by weighing the FDCA solid.

[0058] Example 7

[0059] HMF (12.61 g, 100 mmol), TEMPO (0.078 g, 0.5 mmol), trichloroisocyanuric acid (58.1 g, 250 mmol) and sodium bromide (2.046 g, 20 mmol) were added into a reaction flask containing 50 ml of water and 400 ml of methyl isobutyl ketone as a mixed solvent, and the mixture was dissolved by stirring. Then 0.2 g of concentrated hydrochloric acid was added, and the mixture was heated to 60° C. with stirring for 1 h. After the reaction was completed, the mixture was quickly cooled to room temperature. The reaction product was centrifuged at 3000 rpm for 30 min, and the solid was collected. The solid was washed 3 times with 100 ml of water and freeze-dried in vacuo to obtain a white FDCA solid.

[0060] The purity of the FDCA solid was measured by HPLC to be 98.2%. The molar yield of FDCA was calculated to be 87.2% by weighing the FDCA solid.

[0061] Example 8

[0062] The difference between this embodiment and embodiment 7 is that the trichloroisocyanuric acid in embodiment 7 is replaced by an equal molar amount of chlorobromoisocyanuric acid. The other steps remain unchanged.

[0063] The purity of the FDCA solid was measured by HPLC to be 98.2%. The molar yield of FDCA was calculated to be 87.2% by weighing the FDCA solid.

[0064] Example 9

[0065] The difference between this embodiment and embodiment 7 is that the sodium bromide in embodiment 7 is adjusted from 20 mmol to 40 mmol. The other steps remain unchanged.

[0066] The purity of the FDCA solid was measured by HPLC to be 98.0%. The molar yield of FDCA was calculated by weighing the FDCA solid to be 91.5%.

[0067] Comparative Example 3

[0068] The difference between this comparative example and Example 7 is that the trichloroisocyanuric acid in Example 7 is replaced by an equimolar amount of hypochlorous acid. The other steps remain unchanged.

[0069] The purity of the FDCA solid was measured by HPLC to be 73.2%. The molar yield of FDCA was calculated by weighing the FDCA solid to be 68.1%.

[0070] Comparative Example 4

[0071] The difference between this comparative example and Example 7 is that the trichloroisocyanuric acid in Example 7 is replaced by an equimolar amount of hydrogen peroxide. The other steps remain unchanged.

[0072] The purity of the FDCA solid was measured by HPLC to be 80.6%. The molar yield of FDCA was calculated to be 72.5% by weighing the FDCA solid.

[0073] Comparative Example 5

[0074] The difference between this comparative example and Example 7 is that TEMPO is not added in Example 7. The other steps remain unchanged.

[0075] The purity of the FDCA solid was measured by HPLC to be 85.8%. The molar yield of FDCA was calculated by weighing the FDCA solid to be 60.4%.

[0076] It can be seen from the experiments and results of the above-mentioned embodiments and comparative examples that in the HMF oxidation reaction of the present invention, halogenated isocyanuric acid is used as an oxidant, TEMPO is used as a catalyst, and bromide salt is used as a co-catalyst. The raw material HMF is converted into FDCA with a high conversion rate in an acidic mixed solution, and the purity of FDCA is also high after simple post-treatment.

[0077] As described above, the basic principles, main features and advantages of the present invention are shown and described. Those skilled in the art should understand that the present invention is not limited by the above embodiments, which are only preferred embodiments of the present invention and cannot be used to limit the scope of the present invention. That is, equivalent changes and modifications made according to the scope of the present invention and the content of the specification should still be within the scope of the present invention. The scope of protection required by the present invention is defined by the attached claims and their equivalents.

Claims

1. A method for preparing 2,5-furandicarboxylic acid, characterized in that: 5-Hydroxymethylfurfural, piperidine nitrogen oxide, bromide salt, acid and halogenated isocyanuric acid are subjected to oxidation reaction in a reaction solvent to obtain the 2,5-furandicarboxylic acid.

2. The method for preparing 2,5-furandicarboxylic acid according to claim 1, characterized in that: The reaction solvent is selected from water, an organic solvent or a mixed solvent consisting of water and an organic solvent.

3. The method for preparing 2,5-furandicarboxylic acid according to claim 2, characterized in that: The solubility of the organic solvent in water at 20° C. is not less than 5 g / 100 ml.

4. The method for preparing 2,5-furandicarboxylic acid according to claim 1, characterized in that: The piperidine nitrogen oxide is selected from 2,2,6,6-tetramethylpiperidine nitrogen oxide and its derivatives.

5. The method for preparing 2,5-furandicarboxylic acid according to claim 1, characterized in that: The bromide salt is selected from one or a combination of two or more of sodium bromide, potassium bromide, lithium bromide, calcium bromide, copper bromide, zinc bromide, nickel bromide and magnesium bromide.

6. The method for preparing 2,5-furandicarboxylic acid according to claim 1, characterized in that: The pH of a 1 mol / L aqueous solution of the acid is not higher than 3.

7. The method for preparing 2,5-furandicarboxylic acid according to claim 1, characterized in that: The halogenated isocyanuric acid is selected from one or a combination of two or more of bromoisocyanuric acid, dichloroisocyanuric acid, trichloroisocyanuric acid, chloroisocyanuric acid and chlorobromoisocyanuric acid.

8. The method for preparing 2,5-furandicarboxylic acid according to claim 1, characterized in that: The molar ratio of the 5-hydroxymethylfurfural, the piperidine nitrogen oxide and the halogenated isocyanuric acid is 1:(0.001-0.04):(0.5-5).

9. The method for preparing 2,5-furandicarboxylic acid according to claim 1, characterized in that: The weight ratio of the reaction solvent, the 5-hydroxymethylfurfural, the bromide salt and the acid is (10-100):1:(0.01-1):(0.001-0.1).

10. The method for preparing 2,5-furandicarboxylic acid according to claim 1, characterized in that: The temperature of the oxidation reaction is 15-70°C and the time is 0.5-5h.