A catalyst and its preparation method and its application in catalyzing the oxidation of 5-hydroxymethylfurfural to prepare 2,5-diformylfuran

Abstract

The present application discloses a catalyst and a preparation method thereof and an application thereof in catalyzing the oxidation of 5-hydroxymethylfurfural to prepare 2,5-diformylfuran. The catalyst is a metal vanadyl complex; the metal vanadyl complex is prepared from vanadium oxide and amino acid; the method at least comprises: using oxygen or air as an oxidant, contacting a material containing 5-hydroxymethylfurfural with a catalyst, reacting, and obtaining 2,5-diformylfuran. The method has high oxidation efficiency, high product yield, mild reaction conditions, easy separation of the catalyst from the product, and easy purification of the product. The method has broad application prospects.

Description

Technical Field

[0001] The present application relates to a catalyst and a preparation method thereof and application in catalyzing the oxidation of 5-hydroxymethylfurfural to prepare 2,5-diformylfuran, belonging to the technical field of chemical synthesis. Background Art

[0002] Catalytic conversion of renewable biomass resources to produce high-value-added chemicals and liquid fuels has attracted widespread attention as a supplement to traditional fossil resource synthesis routes. 5-Hydroxymethylfurfural can be produced by dehydration of sugar compounds and is one of the important platform compounds in biorefining. Its molecule contains a furan ring, an aldehyde group and a hydroxymethyl group, and has high reactivity.

[0003] 2,5-Diformylfuran is one of the important oxidation products of 5-hydroxymethylfurfural and has the typical chemical properties of aldehydes. 2,5-Diformylfuran can not only be used as a starting material for fine chemicals such as medicines, macrocyclic ligands, antifungal agents, nematicides, organic ligands, but also can be used as a cross-linking agent for polyvinyl alcohol in battery separators, a component of foundry sand binders, organic phosphors and luminophores, but also an important monomer for furan-based polymers, such as 2,5-diformylfuran and different diamines to synthesize Schiff bases, and urea to synthesize biomass-based new resins, etc., which has a high market value.

[0004] Since the aldehyde group in the 5-hydroxymethylfurfural molecule is easily oxidized to a carboxyl group, and the furan ring is easily hydrolyzed and polymerized by ring opening, it is still difficult to oxidize 5-hydroxymethylfurfural to prepare 2,5-diformylfuran with high selectivity and high conversion rate. Under mild conditions, 2,5-diformylfuran can be prepared with high selectivity by selective oxidation of 5-hydroxymethylfurfural with VOSO4 / Cu(NO3)2 catalysis (Appl. Catal. A, 2014, 482, 231-236), but the nitrogen oxides in this method are easily lost, resulting in the inability to recycle the catalyst. Therefore, it is of great significance to develop a new technology for preparing 2,5-diformylfuran by oxidizing 5-hydroxymethylfurfural with a recyclable catalyst, mild reaction conditions, high yield, easy product separation, and low pollution. Summary of the invention

[0005] According to one aspect of the present application, a catalyst and a method for catalyzing the oxidation of 5-hydroxymethylfurfural to prepare 2,5-diformylfuran are provided, the method is a new oxidation technology with mild reaction conditions, high yield, easy product separation, recyclable catalyst, and low pollution, and molecular oxygen or air is used as an oxidant to catalyze the oxidation of 5-hydroxymethylfurfural to prepare 2,5-diformylfuran. The method has broad application prospects.

[0006] In one aspect of the present application, a catalyst is provided, wherein the catalyst is a metal vanadium complex;

[0007] The metal vanadium complex is prepared from vanadium oxide and amino acid.

[0008] Optionally, the vanadium oxide includes at least one of vanadium acetylacetonate, vanadium trichloride, vanadium phosphate, vanadium dichloride, vanadium sulfate, vanadium acetylacetonate, sodium metavanadate, vanadium dioxide, and vanadium pentoxide.

[0009] Optionally, the amino acids include at least one of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine, and histidine.

[0010] Another aspect of the present application provides a method for preparing the above-mentioned catalyst, the preparation method comprising: adding an aqueous solution containing vanadium oxide to an aqueous solution containing amino acids and sodium acetate, stirring, and vacuum drying to obtain the catalyst.

[0011] As a specific implementation, the preparation method of the catalyst is:

[0012] (1) adding amino acids and sodium acetate in a certain molar ratio into deionized water, stirring thoroughly until the solution becomes clear, to obtain a mixed solution A;

[0013] (2) stirring the mixed solution A at room temperature for 30 minutes, and then adding an aqueous solution containing vanadium oxide to the mixed solution A in a desired proportion to obtain a mixed solution B;

[0014] (3) After the mixture B precipitates, it is stirred at room temperature for 2 h. After the stirring is completed, it is filtered, washed with water and ethanol, and dried in vacuo to obtain a metal vanadium complex.

[0015] Optionally, the ratio of the amount of amino acid to sodium acetate is 0.5 to 1;

[0016] Optionally, the upper limit of the ratio of the amount of the amino acid to the sodium acetate substance is independently selected from 0.6, 0.7, 0.8, 0.9, and 1; the lower limit of the ratio of the amount of the amino acid to the sodium acetate substance is independently selected from 0.5, 0.6, 0.7, 0.8, and 0.9.

[0017] Optionally, the amount of the vanadium oxide is 50 to 100 mol% of the molar amount of the amino acid, wherein the amount of the vanadium oxide is calculated as the amount of metallic vanadium substance;

[0018] Optionally, the upper limit of the molar percentage of the vanadium oxide is independently selected from 52mol%, 55mol%, 60mol%, 65mol%, 70mol%, 75mol%, 80mol%, 85mol%, 90mol%, 95mol%, 100mol%; the lower limit of the molar percentage of the vanadium oxide is independently selected from 50mol%, 53mol%, 58mol%, 63mol%, 68mol%, 73mol%, 78mol%, 83mol%, 88mol%, 93mol%, 98mol%.

[0019] Optionally, the vacuum drying temperature is 40°C to 60°C;

[0020] Optionally, the upper limit of the vacuum drying temperature is independently selected from 45°C, 55°C, and 60°C; the lower limit of the vacuum drying temperature is independently selected from 40°C, 50°C, and 55°C.

[0021] Optionally, the vacuum drying time is 12 h to 24 h.

[0022] Optionally, the upper limit of the vacuum drying time is independently selected from 15h, 18h, 21h, 24h; the lower limit of the vacuum drying time is independently selected from 12h, 15h, 18h, 21h.

[0023] In another aspect of the present application, a method for preparing 2,5-diformylfuran by catalytic oxidation of 5-hydroxymethylfurfural is provided, wherein a raw material containing 5-hydroxymethylfurfural is contacted with a catalyst under an oxygen-containing atmosphere to react and obtain 2,5-diformylfuran;

[0024] The catalyst is selected from the above catalyst or the catalyst obtained according to the above preparation method.

[0025] The method of the present invention is shown in Formula 1:

[0026]

[0027] As a specific embodiment, the method for catalytically oxidizing 5-hydroxymethylfurfural to prepare 2,5-diformylfuran includes: using molecular oxygen or air as an oxidant, with an oxygen partial pressure of 0.02 to 5.0 MPa, reacting at 30 to 180° C. for 0.5 to 24 hours under the action of a catalyst, separating the product, and obtaining 2,5-diformylfuran.

[0028] As a specific implementation, the method for catalyzing the oxidation of 5-hydroxymethylfurfural to prepare 2,5-diformylfuran includes: adding 5-hydroxymethylfurfural, a catalyst and a solvent into a reaction kettle, mixing, heating to 30-180° C., an oxygen partial pressure of 0.02-5.0 MPa, a reaction time of 0.5-24 h, and replenishing oxygen in time when the pressure drops by half during the reaction process, and 5-hydroxymethylfurfural is oxidized to 2,5-diformylfuran.

[0029] Optionally, the amount of the catalyst is 0.1 to 40 mol% of the amount of 5-hydroxymethylfurfural substance, wherein the amount of the catalyst is calculated based on the amount of metal vanadium in the metal vanadium complex.

[0030] Optionally, the upper limit of the molar percentage of the catalyst is independently selected from 0.2mol%, 0.3mol%, 0.6mol%, 1mol%, 3mol%, 6mol%, 9mol%, 12mol%, 15mol%, 16mol%, 19mol%, 21mol%, 23mol%, 25mol%, 27mol%, 30mol%, 32mol%, 36mol%, 40mol%; the lower limit of the mass percentage of the catalyst is independently selected from 0.1mol%, 0.5mol%, 0.8mol%, 0.9mol%, 2mol%, 5mol%, 8mol%, 10mol%, 11mol%, 13mol%, 14mol%, 16mol%, 18mol%, 20mol%, 24mol%, 26mol%, 29mol%, 31mol%, 35mol%, 38mol%.

[0031] Optionally, the oxygen-containing atmosphere is selected from at least one of oxygen and air;

[0032] The raw materials also include a solvent;

[0033] Optionally, the solvent is selected from at least one of dimethyl sulfoxide, acetonitrile, tetrahydrofuran, N,N-dimethylformamide, toluene, 1,4-dioxane, dichloromethane and water;

[0034] Optionally, the reaction temperature is 30-180° C.; the reaction time is 0.5-24 h; the oxygen-containing atmosphere pressure is 0.02-5.0 MPa;

[0035] Optionally, the reaction conditions are:

[0036] The reaction temperature is 45-150°C; the reaction time is 1-12h; and the oxygen-containing atmosphere pressure is 0.05-3.0MPa.

[0037] Optionally, the reaction temperature is 60-120° C.; the reaction time is 1-6 h; and the oxygen partial pressure is 0.1-1.0 MPa.

[0038] Optionally, the upper limit of the reaction temperature is independently selected from 35°C, 45°C, 55°C, 65°C, 75°C, 85°C, 95°C, 105°C, 115°C, 125°C, 135°C, 145°C, 155°C, 165°C, 180°C; the lower limit of the reaction temperature is independently selected from 30°C, 40°C, 50°C, 60°C, 70°C, 80°C, 90°C, 100°C, 110°C, 120°C, 130°C, 140°C, 150°C, 160°C, 175°C.

[0039] Optionally, the upper limit of the reaction time is independently selected from 1h, 3h, 6h, 9h, 12h, 15h, 18h, 21h, 24h; the lower limit of the reaction time is independently selected from 0.5h, 2h, 5h, 8h, 11h, 14h, 16h, 19h, 23h.

[0040] Optionally, the upper limit of the oxygen-containing atmosphere pressure is independently selected from 0.05MPa, 0.08MPa, 0.1MPa, 0.5MPa, 0.6MPa, 0.8MPa, 1.0MPa, 1.4MPa, 1.7MPa, 2.0MPa, 2.3MPa, 2.6MPa, 2.9MPa, 3.1MPa, 3.5MPa, 3.8MPa, 4.2MPa, 4.7MPa, 5.0MPa; the oxygen-containing atmosphere pressure is The lower limit of force is independently selected from 0.02MPa, 0.05MPa, 0.1MPa, 0.2MPa, 0.3MPa, 0.4MPa, 0.7MPa, 0.9MPa, 1.1MPa, 1.3MPa, 1.5MPa, 1.8MPa, 2.2MPa, 2.5MPa, 2.6MPa, 3.0MPa, 3.1MPa, 3.6MPa, 4.0MPa, 4.5MPa, 4.8MPa.

[0041] Optionally, the reaction further includes a separation step;

[0042] The separation at least comprises: removing the catalyst and solvent after the reaction is completed to obtain a solid; adding ethyl acetate to dissolve the solid and then performing vacuum filtration, collecting the filtrate and performing rotary evaporation to remove the ethyl acetate to obtain a solid; adding a sodium bicarbonate aqueous solution to dissolve the solid, extracting with dichloromethane, collecting the lower layer of liquid after extraction and performing rotary evaporation to remove dichloromethane, and obtaining the 2,5-diformylfuran after vacuum drying.

[0043] As a specific embodiment, after obtaining 2,5-diformylfuran, the method further includes separating the 2,5-diformylfuran. The step of separating 2,5-diformylfuran includes: cooling to room temperature after the reaction is completed, filtering to remove the catalyst, and rotary evaporating the mixed solution to remove the solvent; then adding ethyl acetate and vacuum filtration, and rotary evaporating the obtained filtrate to remove ethyl acetate to obtain a solid; then adding sodium bicarbonate aqueous solution to dissolve the solid, extracting with dichloromethane, collecting the lower layer of liquid after extraction, rotary evaporating to remove dichloromethane, and vacuum drying to obtain 2,5-diformylfuran.

[0044] The beneficial effects of this application include:

[0045] 1) The catalytic system used in the present invention has simple reaction operation, uses air or oxygen as an oxidant, and can complete the catalytic reaction in a relatively short time under mild conditions, and the substrate conversion rate and product selectivity can reach more than 99%.

[0046] 2) The metal vanadyl complex catalytic system used in the present invention has high activity, small catalyst dosage, low cost and easy availability, simple and easy preparation process, easy separation and recovery of product and catalyst, and is environmentally friendly and economical.

[0047] 3) The separated and purified products are of high quality. The separated products are tested and analyzed by gas chromatography-mass spectrometry and nuclear magnetic resonance spectrometer, and compared with the retention time of standard samples. The purity reaches more than 99%. DETAILED DESCRIPTION

[0048] The present application is described in detail below with reference to embodiments, but the present application is not limited to these embodiments.

[0049] Unless otherwise specified, the raw materials in the examples of this application were purchased through commercial channels.

[0050] The method for preparing 2,5-diformylfuran by catalytic oxidation of 5-hydroxymethylfurfural in the present application uses a metal vanadyl complex as a catalyst and molecular oxygen or air as an oxidant to oxidize 5-hydroxymethylfurfural and separate the product to obtain 2,5-diformylfuran.

[0051] Preferably, the metal vanadyl complex is prepared from vanadium oxide and amino acid, and the amount of metal vanadium in the metal vanadyl complex is 0.1 to 40 mol% of the amount of the substrate 5-hydroxymethylfurfural.

[0052] Preferably, in the catalyst, the vanadium oxide includes at least one of vanadium acetylacetonate, vanadium trichloride, vanadium phosphate, vanadium dichloride, vanadium sulfate, vanadium acetylacetonate, sodium metavanadate, vanadium dioxide and vanadium pentoxide, and its amount is 50 to 100 mol% of the molar amount of amino acid based on the amount of metallic vanadium.

[0053] Preferably, in the catalyst, the amino acid includes at least one of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine and histidine.

[0054] Preferably, the solvent includes any one of dimethyl sulfoxide, acetonitrile, tetrahydrofuran, N,N-dimethylformamide, toluene, 1,4-dioxane, and dichloromethane.

[0055] In the present application, the method for separating the oxidation product is as follows: after the reaction is completed, the reaction is cooled to room temperature, the catalyst is filtered out, and the mixed solution is rotary evaporated to remove the solvent; ethyl acetate is added and vacuum filtered, and the ethyl acetate is rotary evaporated to remove the ethyl acetate from the obtained filtrate to obtain a solid; then sodium bicarbonate aqueous solution is added to dissolve the solid, and the solid is extracted with dichloromethane. After extraction, the lower layer of liquid is collected and rotary evaporated to remove dichloromethane, and a white solid is obtained after vacuum drying.

[0056] In the specific operation, the metal vanadyl complex, 5-hydroxymethylfurfural and an organic solvent are placed in a reaction kettle, the temperature is raised to 30-180° C., the oxygen partial pressure is 0.02-5.0 MPa, the reaction time is 0.5-24 hours, and 5-hydroxymethylfurfural is oxidized to 2,5-diformylfuran.

[0057] In the present application, the oxygen partial pressure is preferably 0.05 to 3.0 MPa, and most preferably 0.1 to 1.0 MPa; the reaction temperature is preferably 45 to 150° C., and most preferably 60 to 120° C.; the reaction time is preferably 1 to 12 h, and most preferably 1 to 6 h.

[0058] The invention provides a method for preparing 2,5-diformylfuran by catalytic oxidation of 5-hydroxymethylfurfural, wherein the method uses molecular oxygen or air as an oxidant and a metal vanadyl complex as a catalyst to oxidize 5-hydroxymethylfurfural to 2,5-diformylfuran. The 2,5-diformylfuran product prepared by the method has high purity and is green and environmentally friendly.

[0059] The calculation of conversion rate, selectivity and separation rate in the examples of this application is as follows:

[0060]

[0061]

[0062]

[0063] Example 1

[0064] Add 1 mmol alanine and 2 mmol sodium acetate to 2 mL deionized water, stir thoroughly until clear, stir at room temperature for 30 min, add to 2 mL aqueous solution containing 1 mmol acetylacetonatovanadium, continue stirring at room temperature for 2 h after precipitation occurs, filter after stirring, wash with water and ethanol, and dry in vacuo at 40 °C for 12 h to obtain a metal vanadium complex.

[0065] Application Example 1

[0066] 10mmol 5-hydroxymethylfurfural, 0.01mmol metal vanadium complex prepared in Example 1, and 5mL dimethyl sulfoxide were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen for 5 times, 0.02MPa of oxygen was filled, the temperature was raised to 80°C, and the reaction was carried out at this temperature for 1h. When the pressure dropped by half during the reaction, oxygen was added in time. After the reaction was completed, the mixture after the reaction was cooled to room temperature and filtered to remove the catalyst. A certain 1mL of internal standard mesitylene was added, and a sample was taken and analyzed by gas chromatography. The solvent was removed by rotary evaporation, and ethyl acetate was added and vacuum filtered. The filtrate was rotary evaporated to remove ethyl acetate to obtain a solid; then sodium bicarbonate aqueous solution was added to dissolve the solid, and dichloromethane was extracted. After extraction, the lower layer of liquid was collected for rotary evaporation to remove dichloromethane. After vacuum drying, the gas chromatography (GC) purity was measured by Agilent 7890AGC gas phase instrument to reach more than 99%.

[0067] The conversion rate of 5-hydroxymethylfurfural, the GC yield of 2,5-diformylfuran and the separation yield of 2,5-diformylfuran were calculated respectively. The conversion rate of 5-hydroxymethylfurfural was 87%, the GC yield of 2,5-diformylfuran was 85%, and the separation yield of 2,5-diformylfuran was 82%.

[0068] The catalyst obtained by filtration and separation was collected, washed with deionized water and ethanol, and dried under vacuum at 40°C for 12 hours. Multiple cycle experiments were performed under the same reaction conditions. The conversion rate of 5-hydroxymethylfurfural and the GC yield of 2,5-diformylfuran after multiple reactions are shown in the following table:

[0069]

[0070] In other embodiments, the used metal vanadium complex can be subjected to multiple cycle experiments after filtration, washing and drying, and the catalytic activity remains almost unchanged. The specific data of the cycle experiments (i.e., the conversion rate of 5-hydroxymethylfurfural and the GC yield of 2,5-diformylfuran) are no longer listed.

[0071] Example 2

[0072] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by glycine, the molar ratio of glycine to sodium acetate is 1, 1 mmol of acetylacetonatovanadium is replaced by 0.95 mmol of trichlorovanadiumvanadium, and vacuum drying is performed at 50° C. for 15 h.

[0073] Application Example 2

[0074] 10mmol 5-hydroxymethylfurfural, 0.02mmol metal vanadium complex prepared in Example 2, and 5mL acetonitrile were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen for 5 times, 0.05MPa of oxygen was charged, the temperature was raised to 70°C, and the reaction was carried out at this temperature for 2h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 90%, the GC yield of 2,5-diformylfuran was 89%, and the separation yield was 85%.

[0075] Example 3

[0076] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by valine, the molar ratio of valine to sodium acetate is 0.6, 1 mmol of acetylacetonato vanadyl is replaced by 0.90 mmol of vanadyl phosphate, and vacuum drying is performed at 45° C. for 18 h.

[0077] Application Example 3

[0078] 10mmol 5-hydroxymethylfurfural, 0.05mmol metal vanadium complex prepared in Example 3, and 5mL tetrahydrofuran were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with air 5 times, 0.08MPa of air was filled, the temperature was raised to 50°C, and the reaction was carried out at this temperature for 3h. During the reaction, the pressure dropped by half and the air was replenished in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 85%, the GC yield of 2,5-diformylfuran was 82%, and the separation yield was 80%.

[0079] Example 4

[0080] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by leucine, the molar ratio of leucine to sodium acetate is 0.9, 1 mmol of acetylacetonatovanadium is replaced by 0.85 mmol of dichlorovanadium, and vacuum drying is performed at 55° C. for 21 h.

[0081] Application Example 4

[0082] 10mmol 5-hydroxymethylfurfural, 0.08mmol metal vanadium complex prepared in Example 4, and 5mL N,N-dimethylformamide were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 0.1MPa of oxygen was charged, the temperature was raised to 60°C, and the reaction was carried out at this temperature for 4h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 89%, the GC yield of 2,5-diformylfuran was 85%, and the separation yield was 80%.

[0083] Example 5

[0084] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by isoleucine, the molar ratio of isoleucine to sodium acetate is 0.7, 1 mmol of acetylacetonato vanadyl is replaced by 0.80 mmol of vanadyl sulfate, and vacuum drying is performed at 60° C. for 24 h.

[0085] Application Example 5

[0086] 10mmol 5-hydroxymethylfurfural, 0.10mmol metal vanadium complex prepared in Example 5, and 5mL toluene were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen for 5 times, 0.2MPa of oxygen was charged, the temperature was raised to 180°C, and the reaction was carried out at this temperature for 0.5h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled for analysis according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 88%, the GC yield of 2,5-diformylfuran was 84%, and the separation yield was 83%.

[0087] Example 6

[0088] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by methionine, the molar ratio of methionine to sodium acetate is 0.8, 1 mmol of acetylacetonatovanadium is replaced by 0.75 mmol of acetylacetonatovanadium, and vacuum drying is performed at 40° C. for 24 h.

[0089] Application Example 6

[0090] 10mmol 5-hydroxymethylfurfural, 0.20mmol metal vanadium complex prepared in Example 6, and 5mL 1,4-dioxane were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 0.5MPa of oxygen was charged, the temperature was raised to 170°C, and the reaction was carried out at this temperature for 1h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 88%, the GC yield of 2,5-diformylfuran was 83%, and the separation yield was 79%.

[0091] Example 7

[0092] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by proline, the molar ratio of proline to sodium acetate is 0.5, 1 mmol of acetylacetonatovanadium is replaced by 0.70 mmol of sodium metavanadate, and the mixture is vacuum dried at 50° C. for 12 h.

[0093] Application Example 7

[0094] 10mmol 5-hydroxymethylfurfural, 0.50mmol metal vanadium complex prepared in Example 7, and 5mL dichloromethane were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen for 5 times, 0.8MPa of oxygen was charged, the temperature was raised to 160°C, and the reaction was carried out at this temperature for 1h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 98%, the GC yield of 2,5-diformylfuran was 97%, and the separation yield was 93%.

[0095] Example 8

[0096] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by tryptophan, the molar ratio of tryptophan to sodium acetate is 0.75, 1 mmol of acetylacetonatovanadium is replaced by 0.65 mmol of vanadium dioxide, and vacuum drying is performed at 60° C. for 12 h.

[0097] Application Example 8

[0098] 10mmol 5-hydroxymethylfurfural, 0.80mmol metal vanadium complex prepared in Example 8, and 5mL water were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 1.0MPa of oxygen was charged, the temperature was raised to 150°C, and the reaction was carried out at this temperature for 1.5h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled for analysis according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 91%, the GC yield of 2,5-diformylfuran was 88%, and the separation yield was 87%.

[0099] Example 9

[0100] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by serine, the molar ratio of serine to sodium acetate is 0.5, 1 mmol of acetylacetonatovanadium is replaced by 0.60 mmol of vanadium pentoxide, and the mixture is vacuum dried at 45° C. for 21 h.

[0101] Application Example 9

[0102] 10mmol 5-hydroxymethylfurfural, 1.00mmol metal vanadium complex prepared in Example 9, and 5mL dimethyl sulfoxide were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen for 5 times, 1.5MPa of oxygen was charged, the temperature was raised to 140°C, and the reaction was carried out at this temperature for 2h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 85%, the GC yield of 2,5-diformylfuran was 83%, and the separation yield was 80%.

[0103] Example 10

[0104] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by tyrosine, the molar ratio of tyrosine to sodium acetate is 1, 1 mmol of acetylacetonatovanadium is replaced by 0.55 mmol of acetylacetonatovanadium, and vacuum drying is performed at 55° C. for 15 h.

[0105] Application Example 10

[0106] 10mmol 5-hydroxymethylfurfural, 1.50mmol metal vanadium complex prepared in Example 10, and 5mL acetonitrile were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen for 5 times, 2.0MPa of oxygen was charged, the temperature was raised to 130°C, and the reaction was carried out at this temperature for 3h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled for analysis according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 94%, the GC yield of 2,5-diformylfuran was 91%, and the separation yield was 85%.

[0107] Embodiment 11

[0108] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by cysteine, the molar ratio of cysteine ​​to sodium acetate is 0.6, 1 mmol of acetylacetonatovanadium is replaced by 0.50 mmol of trichlorovanadiumvanadium, and vacuum drying is performed at 45° C. for 18 h.

[0109] Application Example 11

[0110] 10mmol 5-hydroxymethylfurfural, 2.00mmol metal vanadyl complex prepared in Example 11, and 5mL tetrahydrofuran were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen for 5 times, 2.5MPa of oxygen was charged, the temperature was raised to 120°C, and the reaction was carried out at this temperature for 4h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 93%, the GC yield of 2,5-diformylfuran was 91%, and the separation yield was 84%.

[0111] Example 12

[0112] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by phenylalanine, the molar ratio of phenylalanine to sodium acetate is 0.9, 1 mmol of acetylacetonato vanadyl is replaced by 1 mmol of vanadyl phosphate, and vacuum drying is performed at 50° C. for 15 h.

[0113] Application Example 12

[0114] 10mmol 5-hydroxymethylfurfural, 2.50mmol metal vanadium complex prepared in Example 12, and 5mL N,N-dimethylformamide were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with air 5 times, 3.0MPa of air was filled, the temperature was raised to 110°C, and the reaction was carried out at this temperature for 6h. During the reaction, the pressure dropped by half and the air was replenished in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 92%, the GC yield of 2,5-diformylfuran was 89%, and the separation yield was 85%.

[0115] Embodiment 13

[0116] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by asparagine, the molar ratio of asparagine to sodium acetate is 0.7, 1 mmol of acetylacetonatovanadium is replaced by 0.90 mmol of dichlorovanadium, and vacuum drying is performed at 40° C. for 18 h.

[0117] Application Example 13

[0118] 10mmol 5-hydroxymethylfurfural, 3.00mmol metal vanadium complex prepared in Example 13, and 5mL toluene were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 3.5MPa of oxygen was charged, the temperature was raised to 100°C, and the reaction was carried out at this temperature for 8h. When the pressure dropped by half during the reaction, oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 95%, the GC yield of 2,5-diformylfuran was 93%, and the separation yield was 88%.

[0119] Embodiment 14

[0120] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by glutamine, the molar ratio of glutamine to sodium acetate is 0.8, 1 mmol of acetylacetonato vanadyl is replaced by 0.80 mmol of vanadyl sulfate, and vacuum drying is performed at 50° C. for 15 h.

[0121] Application Example 14

[0122] 10mmol 5-hydroxymethylfurfural, 3.50mmol metal vanadyl complex prepared in Example 14, and 5mL 1,4-dioxane were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 4.0MPa of oxygen was charged, the temperature was raised to 90°C, and the reaction was carried out at this temperature for 9h. When the pressure dropped by half during the reaction, oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 90%, the GC yield of 2,5-diformylfuran was 87%, and the separation yield was 82%.

[0123] Embodiment 15

[0124] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by threonine, the molar ratio of threonine to sodium acetate is 0.5, 1 mmol of acetylacetonatovanadium is replaced by 0.70 mmol of acetylacetonatovanadium, and vacuum drying is performed at 60° C. for 21 h.

[0125] Application Example 15

[0126] 10mmol 5-hydroxymethylfurfural, 4.00mmol metal vanadium complex prepared in Example 15, and 5mL dichloromethane were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen for 5 times, 4.5MPa of oxygen was charged, the temperature was raised to 80°C, and the reaction was carried out at this temperature for 10h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 95%, the GC yield of 2,5-diformylfuran was 94%, and the separation yield was 92%.

[0127] Example 16

[0128] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by aspartic acid, the molar ratio of aspartic acid to sodium acetate is 0.75, 1 mmol of acetylacetonatovanadium is replaced by 0.60 mmol of sodium metavanadate, and vacuum drying is performed at 45° C. for 24 h.

[0129] Application Example 16

[0130] 10mmol 5-hydroxymethylfurfural, 1.80mmol metal vanadium complex prepared in Example 16, and 5mL water were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 5.0MPa of oxygen was charged, the temperature was raised to 70°C, and the reaction was carried out at this temperature for 12h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 95%, the GC yield of 2,5-diformylfuran was 93%, and the separation yield was 92%.

[0131] Embodiment 17

[0132] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by glutamic acid, the molar ratio of glutamic acid to sodium acetate is 1, 1 mmol of acetylacetonatovanadium is replaced by 0.50 mmol of vanadium dioxide, and vacuum drying is performed at 55° C. for 21 h.

[0133] Application Example 17

[0134] 10mmol 5-hydroxymethylfurfural, 2.70mmol metal vanadium complex prepared in Example 17, and 5mL dimethyl sulfoxide were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with air 5 times, 1.3MPa of air was filled, the temperature was raised to 60°C, and the reaction was carried out at this temperature for 15h. During the reaction, the pressure dropped by half and the air was replenished in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 95%, the GC yield of 2,5-diformylfuran was 93%, and the separation yield was 89%.

[0135] Embodiment 18

[0136] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by lysine, the molar ratio of lysine to sodium acetate is 0.6, 1 mmol of acetylacetonatovanadium is replaced by 0.95 mmol of vanadium pentoxide, and vacuum drying is performed at 40° C. for 24 h.

[0137] Application Example 18

[0138] 10mmol 5-hydroxymethylfurfural, 3.80mmol metal vanadium complex prepared in Example 18, and 5mL acetonitrile were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 0.4MPa of oxygen was charged, the temperature was raised to 50°C, and the reaction was carried out at this temperature for 18h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 95%, the GC yield of 2,5-diformylfuran was 94%, and the separation yield was 93%.

[0139] Embodiment 19

[0140] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by arginine, the molar ratio of arginine to sodium acetate is 0.9, 1 mmol of acetylacetonato vanadyl is replaced by 0.85 mmol of vanadyl sulfate, and vacuum drying is performed at 50° C. for 18 h.

[0141] Application Example 19

[0142] 10mmol 5-hydroxymethylfurfural, 2.30mmol metal vanadyl complex prepared in Example 19, and 5mL tetrahydrofuran were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 0.6MPa of oxygen was charged, the temperature was raised to 40°C, and the reaction was carried out at this temperature for 21h. During the reaction, the pressure dropped by half and oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 95%, the GC yield of 2,5-diformylfuran was 92%, and the separation yield was 90%.

[0143] Embodiment 20

[0144] The difference from the catalyst preparation method in Example 1 is that alanine is replaced by histidine, the molar ratio of histidine to sodium acetate is 0.5, 1 mmol of acetylacetonatovanadium is replaced by 0.75 mmol of acetylacetonatovanadium, and vacuum drying is performed at 40° C. for 15 h.

[0145] Application Example 20

[0146] 10mmol 5-hydroxymethylfurfural, 3.20mmol metal vanadium complex prepared in Example 20, and 5mL N,N-dimethylformamide were added to a 50mL reactor, the reactor was closed, the air in the reactor was replaced with oxygen 5 times, 0.9MPa of oxygen was charged, the temperature was raised to 30°C, and the reaction was carried out at this temperature for 24h. When the pressure dropped by half during the reaction, oxygen was added in time. After the reaction was completed, the reaction was cooled and sampled and analyzed according to the method described in Example 1. The conversion rate of 5-hydroxymethylfurfural was 95%, the GC yield of 2,5-diformylfuran was 93%, and the separation yield was 91%.

[0147] The invention has mild reaction conditions, small amount of catalyst, and is easy to separate from the reaction system after the reaction. The obtained 2,5-diformylfuran product has high purity, reaching more than 99%, and has broad application prospects.

[0148] The above are only a few embodiments of the present application and do not constitute any form of limitation to the present application. Although the present application is disclosed as above with preferred embodiments, it is not intended to limit the present application. Any technician familiar with the profession, without departing from the scope of the technical solution of the present application, using the technical content disclosed above to make slight changes or modifications are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. A method for preparing 2,5-diformylfuran by catalytic oxidation of 5-hydroxymethylfurfural, characterized in that: In an oxygen-containing atmosphere, a raw material containing 5-hydroxymethylfurfural is contacted with a catalyst to react to obtain 2,5-diformylfuran; The catalyst is a metal vanadium complex; The metal vanadium oxycomplex is prepared by the following steps: Adding an aqueous solution containing vanadium oxide to an aqueous solution containing amino acid and sodium acetate, stirring, and vacuum drying to obtain the catalyst; The vanadium oxide is selected from at least one of vanadium acetylacetonate, vanadium trichloride, vanadium phosphate, vanadium dichloride, vanadium sulfate, vanadium acetylacetonate, sodium metavanadate, vanadium dioxide, and vanadium pentoxide; The amino acid is selected from at least one of glycine, alanine, valine, leucine, isoleucine, methionine, proline, tryptophan, serine, tyrosine, cysteine, phenylalanine, asparagine, glutamine, threonine, aspartic acid, glutamic acid, lysine, arginine and histidine.

2. The method according to claim 1, characterized in that The molar ratio of the amino acid to sodium acetate is 0.5-1; The amount of the vanadium oxide is 50-100 mol% of the molar amount of the amino acid, wherein the amount of the vanadium oxide is calculated based on the amount of metallic vanadium.

3. The method according to claim 1, characterized in that The vacuum drying temperature is 40°C to 60°C; The vacuum drying time is 12 h to 24 h.

4. The method according to claim 1, characterized in that: The amount of the catalyst is 0.1 to 40 mol% of the amount of 5-hydroxymethylfurfural substance, wherein the amount of the catalyst is calculated based on the amount of metal vanadium in the metal vanadium complex.

5. The method according to claim 1, characterized in that The oxygen-containing atmosphere is selected from at least one of oxygen and air; The raw materials also include a solvent; The solvent is selected from at least one of dimethyl sulfoxide, acetonitrile, tetrahydrofuran, N,N-dimethylformamide, toluene, 1,4-dioxane, dichloromethane and water; The reaction temperature is 30-180°C; the reaction time is 0.5-24 h; and the oxygen-containing atmosphere pressure is 0.02-5.0 MPa.

6. The method according to claim 1, characterized in that The reaction temperature is 45~150 ℃; the reaction time is 1~12 h; the oxygen-containing atmosphere pressure is 0.05~3.0 MPa.

7. The method according to claim 5, characterized in that The reaction further includes a separation step; The separation at least comprises: removing the catalyst and solvent after the reaction is completed to obtain a solid; adding ethyl acetate to dissolve the solid, and then vacuum filtering and rotary evaporating to obtain a solid; adding sodium bicarbonate aqueous solution to dissolve the solid, extracting with dichloromethane, collecting the lower layer of liquid after extraction, rotary evaporating to remove dichloromethane, and vacuum drying to obtain the 2,5-diformylfuran.

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