A non-noble metal catalyst, a preparation method and application thereof

Abstract

The application discloses a non-noble metal catalyst and a preparation method and application thereof, and the preparation process of the catalyst comprises the following steps: high-temperature calcination of chitin in a nitrogen atmosphere, taking a copper source and an iron source, dissolving in water and fully stirring to be uniform, adding the calcined chitin into the above solution, adding a sodium hypochlorite solution while stirring, continuously stirring for 2 hours, filtering the reaction liquid and cleaning with deionized water, and drying the obtained solid product to obtain a CuFe / Ac catalyst. Then, the catalyst is applied to catalytic preparation of 5-formyl-2-furancarboxylic acid. The application effectively improves the conversion rate, and the preparation process of the catalyst is simple, the cost is low, the time is short, and the reaction is relatively safe.

Description

Technical Field

[0001] This invention belongs to the field of chemical organic synthesis technology, specifically relating to a non-precious metal catalyst, its preparation method, and its application. Background Technology

[0002] As is well known, 5-hydroxymethylfurfural (HMF) is an important bio-based platform compound that can be obtained from renewable resources such as carbohydrates and lignocellulose. HMF can be selectively oxidized to furanyl dicarboxylic acid (FDCA), 2,5-furanyl dicarboxaldehyde (DFF), 5-hydroxymethyl-2-furanyl carboxylic acid (HMFCA), and 5-formyl-2-furanyl carboxylic acid (FFCA). Among these, FFCA is a high-value derivative with formyl, carboxyl, and furan rings, and is widely used in chemical intermediates and drug synthesis. It can also be used to prepare surfactants, and its market prospects are very broad.

[0003] FFCA is an intermediate product in the preparation of FDCA from HMF. Direct oxidation of HMF to FFCA requires the development of highly selective catalysts. Traditional chemical methods involve organic solvents and toxic chemicals to prepare 5-formyl-2-furanoic acid. Patent CN113845500A uses a low-cosolvent and heteropolyacid coupled catalytic oxidation of HMF to FFCA, but the catalyst is difficult to recover. Patent CN110437189B uses photochemical catalysis to prepare FFCA from HMF, but the reaction time is between 4-10 hours, which is relatively long, and the high cost of xenon lamps makes it unsuitable for mass production. Summary of the Invention

[0004] To address the above problems, the present invention aims to provide a non-precious metal catalyst, its preparation method, and its application.

[0005] The specific technical solution is as follows:

[0006] A method for preparing a non-noble metal catalyst includes the following steps:

[0007] 1) Calcine chitin at high temperature in a nitrogen atmosphere;

[0008] 2) Take copper and iron sources, dissolve them in water, and stir thoroughly until homogeneous;

[0009] 3) Add the calcined chitin from step 1) to the solution from step 2), and add sodium hypochlorite solution while stirring. Continue stirring for 2 hours. Filter the reaction solution and wash it with deionized water. Dry the obtained solid product to obtain the CuFe / Ac catalyst.

[0010] Furthermore, in step 1), the chitin is calcined at a high temperature of 500-800℃ for 3-6 hours in a nitrogen atmosphere.

[0011] Furthermore, in step 2), the copper source is copper sulfate pentahydrate, copper nitrate, copper chloride, or copper carbonate, and the iron source is ferric chloride, ferric nitrate, or ferric sulfate.

[0012] A non-precious metal catalyst prepared by the above preparation method.

[0013] The application of a non-precious metal catalyst in the preparation of 5-formyl-2-furan carboxylic acid includes the following steps: adding 5-hydroxymethylfurfural crystals and the prepared non-precious metal catalyst to a reaction vessel, adding hydrogen peroxide and alkali, controlling the reaction temperature, and carrying out the reaction. After the reaction is completed, the sample is collected for liquid chromatography analysis.

[0014] Furthermore, the alkali is sodium carbonate, sodium bicarbonate, potassium hydroxide, or sodium hydroxide.

[0015] Furthermore, the mass ratio of 5-hydroxymethylfurfural crystals to non-precious metal catalyst is 1:0.3-1, and the mass ratio of 5-hydroxymethylfurfural crystals to hydrogen peroxide volume is 1g:2-10mL.

[0016] Furthermore, the reaction temperature is controlled at 60-90℃ and the reaction time is 40-100 min.

[0017] The beneficial effects of this invention are as follows:

[0018] The catalyst of this invention is a non-precious metal, with a simple preparation process, low cost, and reusability. When applied to the preparation of 5-formyl-2-furan carboxylic acid, the catalyst requires a short reaction time, the reaction is relatively safe, and it is suitable for industrial production. Detailed Implementation

[0019] The present invention will be further described below with reference to embodiments, but the scope of protection of the present invention is not limited thereto.

[0020] Example 1

[0021] Preparation of catalysts

[0022] 20g of chitin was calcined at 600℃ in N2 for 4h. 5g of copper sulfate pentahydrate and 3.2g of ferric chloride were dissolved in 15g of deionized water and stirred thoroughly. The calcined chitin was added to the mixed solution of copper sulfate and ferric chloride and stirred for 1h. Then, 20g of sodium hypochlorite solution with a mass concentration of 12% was added dropwise and stirred continuously for 2h. The reaction solution was filtered and washed with deionized water to obtain a solid product. The solid product was dried in an oven at 100℃ to obtain a methylchitin-based CuFe / Ac-a catalyst.

[0023] Examples 2-6

[0024] Catalyst preparation

[0025] The operation steps are the same as in Example 1, except that the amounts of chitosan, copper sulfate pentahydrate, and ferric chloride added are different, as detailed in Table 1.

[0026] Table 1 Summary of the amounts of chitin, copper sulfate pentahydrate, and ferric chloride added in Examples 2 to 5

[0027]

[0028] Example 7

[0029] Preparation of 5-formyl-2-furanoic acid

[0030] 1g of HMF crystals and 0.6g of the catalyst prepared in Examples 1-6 were weighed and added to the reaction vessel. 10ml of 30% hydrogen peroxide and 0.05g of sodium carbonate were added. The reaction temperature was controlled at 70℃ and the reaction time was 90min. After the reaction was completed, the sample was collected for liquid chromatography analysis. The conversion rate of HMF and the yield of FFCA in the reaction system are shown in Table 2.

[0031] Table 2 Summary of HMF conversion and FFCA yield obtained from different catalysts

[0032]

[0033] Table 2 shows that the chitin-based CuFe / Ac-c catalyst has high selectivity for FFAC.

[0034] Examples 8-15

[0035] The operation process was the same as in Example 7, but the chitin-based CuFe / Ac-c catalyst was used. The amounts of catalyst, hydrogen peroxide and sodium carbonate were changed, and the reaction time was also changed. The experimental results are shown in Table 3.

[0036] Table 3 Summary of HMF conversion and FFCA yield under different operating conditions

[0037]

[0038]

[0039] Table 3 shows that, comparing Examples 7 and 8-10, increasing the sodium carbonate concentration within a certain range is beneficial to improving the conversion rate of HMF and the yield of FFCA, but excessively high concentrations will reduce the yield of FFCA. Comparing Examples 7, 11, and 12, improving the catalyst quality is beneficial to improving the conversion rate of HMF and the yield of FFCA. When the catalyst concentration reaches a certain value, the HMF conversion rate and the FFCA yield are comparable. Comparing Examples 7 and 13-15, increasing the hydrogen peroxide concentration is beneficial to improving the conversion rate of HMF and the yield of FFCA. When the hydrogen peroxide concentration reaches a certain value, the HMF conversion rate and the FFCA yield are comparable.

[0040] Repeatability of the catalyst in Examples 16-17

[0041] The operation process is the same as in Example 12, using a chitin-based CuFe / Ac-c catalyst. The catalyst is cleaned and reused. The experimental results are shown in Table 4 without changing other variables. Table 4 shows that the catalyst can be reused.

[0042] Table 4 Catalytic performance of catalysts at different cycle numbers

[0043]

Claims

1. The application of a non-precious metal catalyst in the preparation of 5-formyl-2-furancarboxylic acid, characterized in that, The process includes the following steps: adding 5-hydroxymethylfurfural crystals and the prepared non-precious metal catalyst to a reaction vessel, adding hydrogen peroxide and alkali, controlling the reaction temperature, and carrying out the reaction. After the reaction is completed, the sample is collected for liquid chromatography analysis. The preparation method of non-precious metal catalysts includes the following steps: 1) Calcine chitin at high temperature in a nitrogen atmosphere; 2) Take copper and iron sources, dissolve them in water, and stir thoroughly until homogeneous; 3) Add the calcined chitin from step 1) to the solution from step 2), and add sodium hypochlorite solution while stirring. Continue stirring for 2 hours. Filter the reaction solution and wash it with deionized water. Dry the obtained solid product to obtain the CuFe / Ac catalyst.

2. The application as described in claim 1, characterized in that, In step 1), the chitin is calcined at a high temperature of 500-800℃ for 3-6 hours in a nitrogen atmosphere.

3. The application as described in claim 1, characterized in that, In step 2), the copper source is copper sulfate pentahydrate, copper nitrate, or copper chloride, and the iron source is ferric chloride, ferric nitrate, or ferric sulfate.

4. The application as described in claim 1, characterized in that, The base is potassium hydroxide or sodium hydroxide.

5. The application as described in claim 1, characterized in that, The mass ratio of 5-hydroxymethylfurfural crystals to non-precious metal catalysts is 1:0.3-1, and the mass ratio of 5-hydroxymethylfurfural crystals to hydrogen peroxide volume is 1g:2-10mL.

6. The application as described in claim 1, characterized in that, Control the reaction temperature at 60-90℃ and the reaction time at 40-100 min.

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