Method for preparing 2, 5-furandicarboxylic acid through low-temperature catalytic oxidation of 5-hydroxymethylfurfural

Abstract

According to the method, the zirconium-doped noble metal oxide is used as the catalyst, oxygen in the air or pure oxygen is used as the oxygen source, and the 2, 5-furandicarboxylic acid is prepared by effective catalytic oxidation of the 5-hydroxymethylfurfural under the reaction condition of 20-50 DEG C, so that the problems of low reaction efficiency, violent reaction conditions and the like in the prior art are solved, and the method has a very good utilization prospect.

Description

Technical Field

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

[0002] With the increasing attention paid to sustainable development and environmental protection around the world, the development of technologies for the efficient utilization of biomass resources has become a hot topic in current research. 5-Hydroxymethylfurfural (HMF), as an important biomass platform compound, can be used to prepare high-value-added 2,5-furandicarboxylic acid (FDCA) through catalytic oxidation. FDCA has broad application prospects in the fields of polyester materials. However, traditional catalytic oxidation methods usually need to be carried out under harsh conditions such as high temperature and high pressure, which not only consumes a lot of energy, but also may lead to the occurrence of side reactions, reducing the selectivity and yield of the product.

[0003] In order to solve the above problems, the present invention provides a method for preparing 2,5-furandicarboxylic acid by effectively catalytic oxidation of 5-hydroxymethylfurfural under low temperature conditions using a zirconium-doped precious metal oxide catalyst. In the process of preparing 2,5-furandicarboxylic acid by catalytic oxidation of 5-hydroxymethylfurfural at low temperature, the catalyst of the present invention shows significant advantages. Compared with the traditional method, the method of the present invention can achieve efficient conversion of HMF at 20-50°C, reducing energy consumption and production costs. At the same time, the catalyst has high selectivity for FDCA, reduces the generation of by-products, and improves the purity and yield of the product.

[0004] In summary, the method for preparing 2,5-furandicarboxylic acid by catalytic oxidation of 5-hydroxymethylfurfural under low temperature conditions using zirconium-doped noble metal oxide catalysts of the present invention has significant advantages and broad application prospects. The invention provides an efficient and green technical solution for the conversion and utilization of biomass resources, and has important economic and social value. Summary of the invention

[0005] The object of the present invention is to provide a method for preparing 2,5-furandicarboxylic acid by photocatalytic oxidation of 5-hydroxymethylfurfural at low temperature.

[0006] The first object of the present invention is achieved in this way. The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural is to use 5-hydroxymethylfurfural as a raw material, zirconium-doped precious metal oxide as a catalyst, and carry out oxidation reaction in an alkaline aqueous solution with oxygen in the air or pure oxygen as an oxygen source to obtain the target 2,5-furandicarboxylic acid; the precious metal oxide in the zirconium-doped precious metal oxide is ruthenium oxide, platinum oxide, palladium oxide, rhodium oxide, iridium oxide or gold oxide.

[0007] The specific operations are as follows: The 5-hydroxymethylfurfural and alkaline aqueous solution are mixed and placed in a reaction container, a catalyst is added, and oxygen in the air or pure oxygen is used as an oxygen source to react to obtain the 2,5-furandicarboxylic acid compound, wherein the reaction temperature is 20-50° C., the reaction time is 0.5-6 hours, and the concentration of 5-hydroxymethyl in the alkaline aqueous solution is 8-800 mM; The above catalyst is a zirconium-doped precious metal oxide catalyst, wherein the molar ratio of zirconium to another metal in the catalyst is (0.01-0.2):1, and the precious metal oxide is ruthenium oxide, platinum oxide, palladium oxide, rhodium oxide, iridium oxide or gold oxide.

[0008] The mass ratio of the amount of the above catalyst to the above 5-hydroxymethylfurfural is 0.1-1:1; In a preferred embodiment of the present invention, the molar ratio of zirconium to another metal in the zirconium-doped precious metal oxide is 0.03:1.

[0009] In a preferred embodiment of the present invention, the mass ratio of the amount of the zirconium-doped precious metal oxide to the raw material 5-hydroxymethylfurfural is 0.8:1.

[0010] In a preferred embodiment of the present invention, the temperature of the oxidation reaction is 50°C.

[0011] In a preferred embodiment of the present invention, the oxidation reaction time is 4-6 hours.

[0012] In a preferred embodiment of the present invention, the alkaline aqueous solution is an aqueous solution of sodium carbonate.

[0013] In a preferred embodiment of the present invention, the pressure of the air or oxygen used is 1 MPa.

[0014] In a preferred embodiment of the present invention, the concentration of the raw material 5-hydroxymethylfurfural in the solution is 80 mM.

[0015] The beneficial effects of the present invention are: under low temperature conditions, pure oxygen is used as an oxygen source to efficiently catalyze and oxidize 5-hydroxymethylfurfural to prepare 2,5-furandicarboxylic acid, which solves the problems of low reaction efficiency and severe reaction conditions in the prior art and has good application prospects. DETAILED DESCRIPTION

[0016] The present invention is further described below in conjunction with the embodiments, but the present invention is not limited in any way. Any changes or substitutions made based on the teachings of the present invention belong to the protection scope of the present invention.

[0017] The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural is as follows: 5-hydroxymethylfurfural is used as a raw material, zirconium-doped precious metal oxide is used as a catalyst, and oxygen in the air or pure oxygen is used as an oxygen source to carry out an oxidation reaction in an alkaline aqueous solution to obtain the target 2,5-furandicarboxylic acid; the precious metal oxide in the zirconium-doped precious metal oxide is ruthenium oxide, platinum oxide, palladium oxide, rhodium oxide, tin oxide or gold oxide.

[0018] The alkaline aqueous solution is an aqueous solution containing sodium hydroxide, sodium carbonate, sodium bicarbonate, potassium hydroxide, potassium carbonate or potassium bicarbonate.

[0019] The molar ratio of zirconium to another metal in the zirconium-doped precious metal oxide is (0.01-0.2):1.

[0020] The mass ratio of the amount of the zirconium-doped noble metal oxide to the raw material 5-hydroxymethylfurfural is (0.1-1):1.

[0021] The temperature of the oxidation reaction is 20-50°C.

[0022] The oxidation reaction time is 0.5 to 6 hours.

[0023] The pressure of the oxidation reaction is 0.1~2MPa.

[0024] The concentration of the raw material 5-hydroxymethylfurfural in the reaction solution is controlled at 8-800 mM.

[0025] The present invention is further described below with specific implementation cases: The preparation process of the catalyst used in the following examples is based on the paper published by Huai Liu et al. ( ACS Catal. 2021,11,13,7828–7844), the specific steps are as follows: first, zirconium oxychloride and another metal salt are weighed and put into an agate mortar, then water and ascorbic acid (VC) are added, and the mixture is manually ground for 5 min to mix evenly, and then calcined at 350 ° C in a muffle furnace under air atmosphere for 2 h to obtain a zirconium-doped noble metal oxide catalyst, which is labeled as Zr x M-yVC, where M represents the type of the second metal, x represents the molar ratio of Zr to the second metal, and y represents the molar ratio of VC added during the grinding process to the total metal content.

[0026] Examples 1-6 0.03 g 5-hydroxymethylfurfural, 0.026 g sodium carbonate and 3 g water were added to a 10 mL autoclave, and 0.025 g Zr 3 Ru-0.2VC, Zr 3 Pt-0.2VC, Zr3 Pd-0.2VC, Zr 3 Rh-0.2VC, Zr 3 Ir-0.2VC, Zr 3 Au-0.2VC catalyst; after sealing the reactor, oxygen was introduced to increase the pressure to 10 bar, and then heated to 50°C under vigorous stirring (600 rpm) and maintained for 4 hours to terminate the reaction. HPLC (Water 2487) was used for qualitative and quantitative detection, and the test results are listed in Table 1, with serial numbers 1-6.

[0027] Examples 7-10 0.03 g 5-hydroxymethylfurfural, 0.026 g sodium carbonate and 3 g water were added to a 10 mL autoclave, and 0.025 g Zr 1 Ru-0.2VC, Zr 5 Ru-0.2VC, Zr 10 Ru-0.2VC, Zr 20 Ru-0.2VC catalyst; after sealing the reactor, oxygen was introduced to increase the pressure to 10 bar, and then heated to 50°C under vigorous stirring (600 rpm) and maintained for 4 hours to terminate the reaction. HPLC (Water2487) was used for qualitative and quantitative detection, and the test results are listed in Table 1, with serial numbers 7-10.

[0028] Examples 11-12 0.03 g 5-hydroxymethylfurfural, 0.026 g sodium carbonate and 3 g water were added to a 10 mL autoclave, and 0.025 g Zr 3 Ru-0.2VC catalyst; after sealing the reactor, oxygen was introduced to increase the pressure to 10 bar, and then heated to 30 and 40°C under vigorous stirring (600 rpm) and maintained for 6 and 4 hours to terminate the reaction. HPLC (Water 2487) was used for qualitative and quantitative detection, and the test results are listed in Table 1, serial numbers 11-12.

[0029] Examples 13-14 In a 10 mL autoclave, 0.15 g and 0.3 g of 5-hydroxymethylfurfural (400 mM and 800 mM), 0.026 g of sodium carbonate and 3 g of water were added, and then 0.12 and 0.25 g of Zr 3 Ru-0.2VC catalyst; after sealing the reactor, oxygen was introduced to increase the pressure to 10 bar, and then heated to 50°C under vigorous stirring (600 rpm) and maintained for 6 hours to terminate the reaction. HPLC (Water 2487) was used for qualitative and quantitative detection, and the test results are listed in Table 1, serial numbers 13-14.

[0030] Examples 15-19 In a 10 mL autoclave, 0.03 g of 5-hydroxymethylfurfural, 0.026 g of sodium hydroxide, sodium bicarbonate, potassium hydroxide, potassium carbonate or potassium bicarbonate and 3 g of water were added, and 0.025 g of Zr 3 Ru-0.2VC catalyst; after sealing the reactor, oxygen was introduced to increase the pressure to 10 bar, and then heated to 50°C under vigorous stirring (600 rpm) and maintained for 4 hours to terminate the reaction. HPLC (Water 2487) was used for qualitative and quantitative detection, and the test results are listed in Table 1, serial numbers 15-19.

[0031] Examples 20-21 0.03 g 5-hydroxymethylfurfural, 0.026 g sodium carbonate and 3 g water were added to a 10 mL autoclave, and 0.025 g Zr 3 Ru-0.2VC catalyst; after sealing the reactor, oxygen was introduced to increase the pressure to 15, 20 bar, and then heated to 50°C under vigorous stirring (600 rpm) and maintained for 4 hours to terminate the reaction. HPLC (Water 2487) was used for qualitative and quantitative detection, and the test results are listed in Table 1, serial number 20-21.

[0032] Table 1 Test results in each embodiment

[0033] The above description is only a preferred embodiment of the present invention, and therefore cannot be used to limit the scope of implementation of the present invention. That is, equivalent changes and modifications made according to the patent scope of the present invention and the contents of the specification should still fall within the scope of the present invention.

Claims

1. A method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural, characterized in that: The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural is to use 5-hydroxymethylfurfural as a raw material, zirconium-doped precious metal oxide as a catalyst, and carry out oxidation reaction in an alkaline aqueous solution with oxygen in the air or pure oxygen as an oxygen source to obtain the target 2,5-furandicarboxylic acid; the precious metal oxide in the zirconium-doped precious metal oxide is ruthenium oxide, platinum oxide, palladium oxide, rhodium oxide, tin oxide or gold oxide.

2. The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural according to claim 1, characterized in that: The alkaline aqueous solution is an aqueous solution containing sodium hydroxide, sodium carbonate, sodium bicarbonate, potassium hydroxide, potassium carbonate or potassium bicarbonate.

3. The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural according to claim 1, characterized in that: The molar ratio of zirconium to another metal in the zirconium-doped precious metal oxide is (0.01-0.2):

1.

4. The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural according to claim 1, characterized in that: The mass ratio of the amount of the zirconium-doped noble metal oxide to the raw material 5-hydroxymethylfurfural is (0.1-1):

1.

5. The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural according to claim 1, characterized in that: The temperature of the oxidation reaction is 20-50°C.

6. The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural according to claim 1, characterized in that: The oxidation reaction time is 0.5 to 6 hours.

7. The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural according to claim 1, characterized in that: The pressure of the oxidation reaction is 0.1~2MPa.

8. The method for preparing 2,5-furandicarboxylic acid by low-temperature catalytic oxidation of 5-hydroxymethylfurfural according to claim 1, characterized in that: The concentration of the raw material 5-hydroxymethylfurfural in the reaction solution is controlled at 8-800 mM.

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