CN117138799A - A method for preparing a bimetal-supported catalyst and a method for preparing hemiacetal from furan aldehyde and alcohol - Google Patents

Abstract

The invention discloses a preparation method of a bimetallic supported catalyst and a method of preparing hemiacetal from furan aldehyde and alcohol. The preparation method of the bimetallic supported catalyst includes the following steps: mixing the carrier Y with the precursor salt of the active metal M1 , let stand at room temperature and dry to obtain solid A; bake solid A in an air atmosphere to obtain solid B; mix the precursor salt of active metal M2, solid B and deionized water, adjust the acidity and alkalinity of the mixed solution, and add The hydrogen donor reducing agent uses the hydrogen donor reduction method to load the active metal M2 onto the solid B. The product is filtered and dried to obtain a bimetallic supported catalyst. The invention prepares a catalyst loaded with two active metals through the above preparation method. The catalyst has high stability, the two active components play a synergistic effect, improve the activity of the catalyst, and has high conversion rate and high efficiency for hemiacetal reaction. Selectivity.

Description

A kind of preparation method of bimetal supported catalyst and preparation of furan aldehyde and alcohol hemicondensate aldehyde method

Technical field

The invention relates to the technical field of organic catalytic conversion, and in particular to a method for preparing a bimetal-supported catalyst and a method for preparing hemiacetal from furan aldehyde and alcohol.

Background technique

With the continuous development of traditional industries and the rapid growth of the earth's population, the contradiction between the reduction of non-renewable resource reserves and the increase in fuel demand, as well as the environmental pollution caused by the overuse and development of fossil resources, have become huge challenges facing mankind. challenge. In order to get out of this dilemma, mankind has focused its future development on renewable energy sources such as wind energy, solar energy, and biomass energy. As the only renewable organic carbon source in nature, biomass is environmentally friendly, abundant in reserves, and low-cost. It can be used as a raw material for the production of high value-added chemicals and materials.

Furan aldehyde is a widely used biomass platform compound. It is produced by the hydrolysis of biomass raw materials such as cellulose. Its molecules contain aldehyde groups and hydroxyl groups and can be derived through chemical reactions such as catalytic hydrogenation, oxidative dehydrogenation, esterification, and halogenation. Many furan chemical products are produced. At present, the focus of scientific research on biomass conversion focuses on the synthesis of furanal aldehyde from monosaccharides or disaccharides produced by biomass hydrolysis. The preparation of its derivatives is mostly limited to oxidation reactions, while hemiacetalization reactions are rarely involved. . The aldehyde group of furan aldehyde can undergo a hemiacetal reaction with a chain monovalent saturated alcohol. The product can not only be used to produce a series of derivatives, but also can be used as food flavoring and fuel additives, or directly used as biofuel. It can be seen that the application value of hemiacetal reaction is very huge, and it has very large application potential and market.

Existing catalysts have low selectivity for hemiacetalization reactions and poor stability, and the yield of hemiacetal products is often unsatisfactory. Although some precious metal catalysts can bring higher yields of hemiacetal products, their high prices greatly increase the production cost of this biomass conversion and further limit the application and promotion of hemiacetal derivatives. Conducive to expanding production.

Contents of the invention

In view of the shortcomings of the existing technology, the technical problem to be solved by the present invention is how to develop a cheap and efficient catalyst to improve the conversion rate and selectivity of the hemiacetalization reaction.

In order to solve the above technical problems, the first aspect of the present invention provides a preparation method of a bimetal-supported catalyst, which includes the following steps:

S11. Mix the precursor salt of the carrier Y and the active metal M1, use the impregnation method to load the active metal M1 onto the carrier Y, let it stand at room temperature, and dry it to obtain solid A. The carrier Y is a metal. Oxide, the active metal M1 is a non-noble metal;

S12. Calcining the solid A in an air atmosphere to obtain solid B;

S13. Mix the precursor salt of the active metal M2, the solid B and deionized water, adjust the acidity and alkalinity of the mixed solution, add a hydrogen donor reducing agent, and use the hydrogen donor reduction method to load the active metal M2 to the desired location. On the solid B, the active metal M2 is a precious metal, and the product is filtered and dried to obtain a bimetallic supported catalyst.

The present invention prepares a catalyst loaded with two active metals through the above preparation method. The two active components play a synergistic effect, improve the activity of the catalyst, and are suitable for catalyzing the condensation of furan aldehydes to obtain hemiacetal compounds. For hemiacetals The reaction has high conversion rate and high selectivity; it is also conducive to reducing the use of precious metals and reducing catalyst costs; and the prepared catalyst has high stability and can be recycled and reused.

Further, the step S13 specifically includes: mixing the solid B with deionized water, heating and stirring for 1-2 hours; adding sodium hydroxide aqueous solution to adjust the pH to 8-9; adding the precursor salt of the active metal M2 , stir for 2-5h; add reducing agent, continue stirring for 4-6h; filter to obtain the product, wash and dry to obtain a bimetal-supported catalyst. In this step, the active metal M2 is loaded through the hydrogen donor reduction method. The process conditions are mild and will not affect the active metal M1 loaded on the carrier, so that the two active metals are evenly distributed, which is conducive to achieving a synergistic catalytic effect.

Further, the hydrogen donor reducing agent is selected from at least one of formic acid, hydrazine hydrate, ammoniaborane, ammonium formate, sodium formate, cyclohexene, decalin, and tetralin.

Further, the carrier Y is selected from at least one of MoO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , CeO ₂ and ZnO.

Further, the active metal M1 is selected from at least one of Co, Ni, Cu, Sc, Ti, Cr, Mn, Fe, and Zn.

Further, the active metal M2 is selected from at least one of Ru, Pt, Pd, Au, Ag, Ir, Rh, and Os.

Further, the mass proportion of the active metal M1 in the bimetal-supported catalyst is 1% to 4%.

Further, the mass proportion of the active metal M2 is 0.01% to 0.1%.

The catalyst supports two active metals, which can have a synergistic effect and improve the catalytic effect. Therefore, less amount of each active component is required, which is beneficial to reducing catalyst costs.

A second aspect of the invention provides a method for preparing hemiacetal from furan aldehyde and alcohol, which includes the following steps:

S21. Add the bimetal-supported catalyst, furan aldehyde and alcoholic organic solvent prepared by the above preparation method to the reaction device to form a mixed solution;

S22. Pour hydrogen gas into the reaction device to perform a condensation reaction to obtain hemiacetal compounds.

In the present invention, a bimetal-supported catalyst is used to catalyze the hemiacetalization reaction. The above preparation method has the advantages of simple process, high furan aldehyde conversion rate, high hemiacetal selectivity, and high product purity.

Further, in step S22, the reaction temperature is 80°C to 140°C, the pressure is 0.5MPa to 4MPa, and the time is 0.5h to 8h. The method for preparing hemiacetal from furan aldehyde and alcohol according to the invention has relatively mild reaction conditions and a short reaction cycle, which is beneficial to industrial application.

Further, in step S21, the molar ratio of the furan aldehyde to the bimetal-supported catalyst is 3500 to 40000:1. The bimetal-supported catalyst has high reaction activity and requires a small amount to catalyze the hemiacetalization reaction, which is beneficial to reducing the cost of preparing hemiacetal compounds.

Further, in the step S21, the molar concentration of the furan aldehyde in the mixed solution is 0.1M to 1M. Control the molar concentration of furan aldehyde to ensure sufficient reaction and high conversion rate.

Further, the furan aldehyde is selected from the group consisting of furfural, 5-methylfurfural, 5-hydroxymethylfurfural, 2,5-diformylfuran, 2-furyl ethanol, 5-chloromethylfuran, 4-hydroxymethyl At least one of furfural and 2,5-furandicarbaldehyde.

Further, the alcoholic organic solvent is selected from the group consisting of methanol, ethanol, ethylene glycol, n-propanol, isopropanol, n-butanol, isobutanol, n-amyl alcohol, iso-amyl alcohol, n-hexanol and iso-hexanol. At least one.

The bimetal-supported catalyst of the present invention has good catalytic effect on a variety of furan aldehydes and alcohols, can catalyze the condensation of furan aldehydes to obtain hemiacetal compounds, and has high conversion rate and selectivity.

In summary, compared with the prior art, the present invention has the following beneficial effects:

1) The present invention prepares a catalyst loaded with two active metals through a specific process. The catalyst has high stability and can be used repeatedly. The two active metals play a synergistic effect, making the catalyst highly active under mild reaction conditions and in a short time. Within the reaction time, the condensation of furan aldehydes and alcohols can be catalyzed to prepare hemiacetal compounds.

2) The bimetallic supported catalyst of the present invention uses less precious metal components and has low preparation cost, which is beneficial to the application and promotion of hemiacetal derivatives and the expansion of production in the future.

3) The bimetal-supported catalyst of the present invention has high conversion rate and selectivity for the hemiacetalization reaction of furan aldehyde, with a conversion rate of up to 70% and a selectivity of up to 100%.

4) The bimetallic supported catalyst of the present invention uses less precious metal components and has low preparation cost, which is beneficial to the application and promotion of hemiacetal derivatives and the expansion of production in the future.

Description of the drawings

Figure 1 is a route diagram for preparing hemiacetal by condensing HMF with alcohols in a hydrogen atmosphere in Example 1 of the present invention.

Detailed ways

In order to make the above objects, features and advantages of the present invention more obvious and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings.

It should be understood that the terms used in the present invention are only used to describe particular embodiments and are not intended to limit the present invention. In addition, for numerical ranges in the present invention, it should be understood that every intermediate value between the upper and lower limits of the range is also specifically disclosed. Every smaller range between any stated value or value intermediate within a stated range and any other stated value or value intermediate within a stated range is also included within the invention. The upper and lower limits of these smaller ranges may independently be included or excluded from the range.

It will be apparent to those skilled in the art that various modifications and changes can be made to the specific embodiments described herein without departing from the scope or spirit of the invention. Other embodiments will be apparent to the skilled person from the description of the invention. The specification and examples are intended to be illustrative only.

A specific embodiment of the present invention provides a bimetal-supported catalyst, which is suitable for catalyzing the hemiacetalization reaction of furan aldehyde and alcohol. The bimetallic supported catalyst includes a carrier Y and active metal M1 and active metal M2 supported on it. The carrier Y is a metal oxide, such as MoO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , CeO ₂ , ZnO, etc. ; Active metal M1 is a non-noble metal, such as Co, Ni, Cu, Sc, Ti, Cr, Mn, Fe, Zn, etc.; Active metal M2 is a noble metal, such as Ru, Pt, Pd, Au, Ag, Ir, Rh, Os, etc. . The two active components act synergistically to increase the activity of the catalyst.

In specific embodiments, the mass proportion of active metal M1 in the bimetal-supported catalyst is 1% to 4%, and the mass proportion of active metal M2 is 0.01% to 0.1%. Typical mass fractions of active metal M1 include 1%, 1.2%, 1.4%, 1.6%, 1.8%, 2%, 2.2%, 2.4%, 2.6%, 2.8%, 3%, 3.2%, 3.4%, 3.6%, 3.8%, 4%, etc.; typical mass fractions of active metal M2 include 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, 0.09%, 0.1%, etc.

The preparation method of the above-mentioned supported metal catalyst includes the following steps:

S11. Mix the carrier Y and the precursor salt of the active metal M1, use the impregnation method to load the active metal M1 onto the carrier Y, let it stand at room temperature, and dry it to obtain solid A.

S12. Calculate solid A obtained in step S11 to obtain solid B. The roasting step turns the precursor salt of the active metal M1 into a metal oxide while controlling the growth of metal particles.

In specific embodiments, the calcination temperature is 200°C to 900°C, and the time is 2h to 15h. Typical calcination temperatures include 300°C, 350°C, 400°C, 450°C, 500°C, 550°C, 600°C, 650°C, and 700°C. wait.

S13. Mix the solid B with deionized water, heat and stir for 1-2 hours; add sodium hydroxide aqueous solution to adjust the pH to 8-9; add the precursor salt of the active metal M2, stir for 2-5 hours; add hydrogen Donate the reducing agent and continue stirring for 4-6 hours; filter to obtain the product, wash and dry to obtain a bimetal-supported catalyst.

In specific embodiments, the precursors of active metal M1 and active metal M2 are independently selected from corresponding nitrates, chloride salts, acetates, acetylacetonates, etc.

In specific embodiments, the hydrogen donor reducing agent is selected from the group consisting of formic acid, hydrazine hydrate, ammoniaborane, ammonium formate, sodium formate, cyclohexene, decalin, tetrahydronaphthalene, and the like.

The above preparation method combines the impregnation method and the hydrogen donor reduction method, so that two active metals are loaded on the carrier, and the catalyst has high stability. The two active metals can have a synergistic catalytic effect, making the catalyst highly active and resistant to hemiacetals. Highly selective.

The specific embodiment of the present invention also provides a method for preparing hemiacetal from furan aldehyde and alcohol, which specifically includes the following steps:

S21. Add the bimetal-supported catalyst, furan aldehyde and alcoholic organic solvent prepared by the present invention into the reaction device to form a mixed solution.

In specific embodiments, the furan aldehyde can be selected from the group consisting of furfural, 5-methylfurfural, 5-hydroxymethylfurfural, 2,5-diformylfuran, 2-furyl ethanol, 5-chloromethylfuran, 4-Hydroxymethylfurfural, 2,5-furandicarbaldehyde, etc.; alcoholic organic solvents can choose methanol, ethanol, ethylene glycol, n-propanol, isopropanol, n-butanol, isobutanol, n-pentanol, Isoamyl alcohol, n-hexanol, isohexyl alcohol, etc.

Preferably, the molar ratio of furan aldehyde to bimetallic supported catalyst is 3500-40000:1. Typical molar ratios include 3500:1, 4000:1, 4500:1, 5000:1, 5500:1, 6000:1, 6500 : 1, 7000: 1, 7500: 1, 8000: 1, 8500: 1, 9000: 1, 9500: 1, 10000: 1, 15000: 1, 20000: 1, 25000: 1, 30000: 1, 35000: 1 , 40000:1 etc.

The molar concentration of furan aldehyde in the mixed solution is 0.1M ~ 1M. Typical molar concentrations include 0.1M, 0.2M, 0.3M, 0.4M, 0.5M, 0.6M, 0.7M, 0.8M, 0.9M, 1M, etc.

S22. Pour hydrogen gas into the reaction device to perform a condensation reaction to obtain hemiacetal compounds.

In specific embodiments, the reaction conditions are as follows: temperature is 80°C to 140°C, pressure is 0.5MPa to 4MPa, and time is 0.5h to 8h. Typical reaction temperatures include 80°C, 85°C, 90°C, 95°C, 100°C, 105°C, 110°C, 115°C, 120°C, 125°C, 130°C, 135°C, 140°C, etc.; typical reaction times include 0.5h , 1h, 1.5h, 2h, 2.5h, 3h, 3.5h, 4h, 4.5h, 5h, 5.5h, 6h, 6.5h, 7h, 7.5h, 8h, etc.; typical reaction pressures include 0.5MPa, 1MPa, 1.5MPa , 2MPa, 2.5MPa, 3MPa, 3.5MPa, 4MPa, etc.

The above method uses a bimetal-supported catalyst for the hemiacetalization reaction of furan aldehyde and alcohol, and can prepare high-purity hemiacetal products under mild reaction conditions and a short reaction time, and the hemiacetalization reaction High conversion rate and selectivity.

The technical effects of the present invention will be described below with reference to specific embodiments. Unless otherwise specified, the raw materials in the examples of this application were all purchased through commercial channels. In the examples, the conversion rate and selectivity are calculated as follows:

HMF conversion rate = (initial HMF concentration - HMF concentration after reaction)/initial HMF concentration × 100%;

Hemiacetal yield = hemiacetal concentration after reaction/initial hemiacetal concentration × 100%;

Hemiacetal selectivity = hemiacetal yield/HMF conversion rate × 100%.

Example 1

(1) Prepare a bimetal-supported catalyst. The specific steps are as follows:

(1.1) Mix the hexahydrate copper nitrate aqueous solution and molybdenum dioxide powder with a concentration of 0.6M in a ratio of 1:1, stir thoroughly and mix evenly; dry the surface moisture at 80°C and let it stand at room temperature for 12 hours; then grind it into The powder was calcined at 800°C for 5 hours to obtain solid CuO/MoO ₂ in which Cu was supported on MoO ₂ .

(1.2) Add the CuO/MoO ₂ obtained in step (1.1) to deionized water, heat and stir for 2 hours; add NaOH aqueous solution with a concentration of 1M to adjust the pH to 8; add H ₂ PtCl ₆ solution, the mass concentration of Pt is 1 mg/mL , stir for 2 hours; then add the reducing agent formic acid solution and continue stirring for 4 hours; filter and wash with deionized water until the pH is neutral, and keep the filter cake at 90°C for 10 hours to dry; then grind the filter cake to powder to obtain Cu and Pt loads The bimetallic supported catalyst on MoO ₂ is designated as Cu-Pt/MoO ₂ -FA.

(2) Catalytic activity test, Cu-Pt/MoO ₂ -FA catalyst is used to catalyze the reaction of 5-hydroxymethylfurfural condensation to prepare hemiacetal. The specific operation process is as follows:

Dissolve 5-hydroxymethylfurfural in the ethanol solvent, add Cu-Pt/MoO ₂ -FA bimetallic supported catalyst, so that the concentration of 5-hydroxymethylfurfural is 0.1M, and the ratio between 5-hydroxymethylfurfural and the catalyst is The molar ratio is 10000:1; keep the hydrogen pressure at 1MPa and the temperature at 100°C for 3 hours. 5-hydroxymethylfurfural and ethanol undergo a hemiacetalization reaction in a hydrogen environment. The reaction principle is shown in Figure 1; after the reaction is completed , for cooling; the catalyst is separated from the reaction liquid through filtration, and the catalyst is dried after repeated washing and ready for recycling; the reaction liquid is filtered and quantitatively analyzed using high-performance gas chromatography.

The measured 5-hydroxymethylfurfural conversion rate of the reaction was 71%, the hemiacetal yield was 70%, and the hemiacetal selectivity was 98.6%. The results show that the bimetal-supported catalyst prepared in this example has excellent performance. .

(3) Catalyst stability test, the specific operation process is as follows:

The Cu-Pt/MoO ₂ -FA recovered in step (2) was again used to catalyze the condensation of 5-hydroxymethylfurfural to prepare hemiacetal, and its catalytic activity was tested. The test steps and conditions were the same as in step (2). Four more cycles were carried out using this method, and the hemiacetal yields each time were 69.5%, 68.3%, 67.6% and 65.8% respectively.

Catalytic performance evaluation results show that during recycling, the catalyst activity loss is low and the stability is good.

Example 2

Using the same preparation steps as in Example 1, using MoO ₂ as the carrier, Cu as the active metal M1, Pd as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Cu-Pd/MoO ₂ -FA was prepared.

Using the catalytic activity testing method of Example 1, it was determined that the 5-hydroxymethylfurfural conversion rate of the reaction was 67.2%, the hemiacetal yield was 65.1%, and the hemiacetal selectivity was 96.9%.

Example 3

Using the same preparation steps as in Example 1, using MoO ₂ as the carrier, Cu as the active metal M1, Ru as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Cu-Ru/MoO ₂ -FA was prepared.

Using the catalytic activity test method of Example 1, it was determined that the 5-hydroxymethylfurfural conversion rate of the reaction was 66.5%, the hemiacetal yield was 64.2%, and the hemiacetal selectivity was 96.5%.

Example 4

Using the same preparation steps as in Example 1, using MoO ₂ as the carrier, Cu as the active metal M1, Au as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Cu-Au/MoO ₂ -FA was prepared.

Using the catalytic activity test method of Example 1, it was measured that the 5-hydroxymethylfurfural conversion rate of the reaction was 59.6%, the hemiacetal yield was 55.5%, and the hemiacetal selectivity was 93.1%.

Example 5

Using the same preparation steps as in Example 1, using MoO ₂ as the carrier, Cu as the active metal M1, Ir as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Cu-Ir/MoO ₂ -FA was prepared.

Using the catalytic activity test method of Example 1, it was determined that the 5-hydroxymethylfurfural conversion rate of the reaction was 52.2%, the hemiacetal yield was 50%, and the hemiacetal selectivity was 95.8%.

Example 6

Using the same preparation steps as in Example 1, using Al ₂ O ₃ as the carrier, Cu as the active metal M1, Pt as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Cu-Pt/Al ₂ O ₃ - was prepared. FA.

Using the catalytic activity test method of Example 1, it was determined that the 5-hydroxymethylfurfural conversion rate of the reaction was 63.2%, the hemiacetal yield was 54.3%, and the hemiacetal selectivity was 85.9%.

Example 7

Using the same preparation steps as in Example 1, using In ₂ O ₃ as the carrier, Cu as the active metal M1, Pt as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Cu-Pt/In ₂ O ₃ - was prepared. FA.

Using the catalytic activity test method of Example 1, it was determined that the conversion rate of 5-hydroxymethylfurfural in the reaction was 58.5%, the yield of hemiacetal was 55.2%, and the selectivity of hemiacetal was 94.4%.

Example 8

Using the same preparation steps as in Example 1, using SiO ₂ as the carrier, Cu as the active metal M1, Pt as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Cu-Pt/SiO ₂ -FA was prepared.

Using the catalytic activity testing method of Example 1, it was determined that the 5-hydroxymethylfurfural conversion rate of the reaction was 58.4%, the hemiacetal yield was 47.1%, and the hemiacetal selectivity was 80.6%.

Example 9

Using the same preparation steps as in Example 1, using CeO ₂ as the carrier, Cu as the active metal M1, Pt as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Cu-Pt/CeO ₂ -FA was prepared.

Using the catalytic activity test method of Example 1, it was determined that the 5-hydroxymethylfurfural conversion rate of the reaction was 53%, the hemiacetal yield was 44.3%, and the hemiacetal selectivity was 83.6%.

Example 10

Using the same preparation steps as in Example 1, using MoO ₂ as the carrier, Co as the active metal M1, Pt as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Co-Pt/MoO ₂ -FA was prepared.

Using the catalytic activity test method of Example 1, it was measured that the conversion rate of 5-hydroxymethylfurfural in the reaction was 46.2%, the yield of hemiacetal was 32.2%, and the selectivity of hemiacetal was 69.7%.

Example 11

Using the same preparation steps as in Example 1, using MoO ₂ as the carrier, Ni as the active metal M1, Pt as the active metal M2, and formic acid as the hydrogen donor, a bimetallic supported catalyst Ni-Pt/MoO ₂ -FA was prepared.

Using the catalytic activity test method of Example 1, the conversion rate of 5-hydroxymethylfurfural in the reaction was measured to be 40%, the yield of hemiacetal was 30.8%, and the selectivity of hemiacetal was 77%.

Example 12

Using the same preparation steps as in Example 1, using MoO ₂ as the carrier, Cu as the active metal M1, Pt as the active metal M2, and hydrazine hydrate as the hydrogen donor, a bimetal-supported catalyst Cu-Pt/MoO ₂ -NH was prepared.

Using the catalytic activity test method of Example 1, it was determined that the 5-hydroxymethylfurfural conversion rate of the reaction was 68.8%, the hemiacetal yield was 66%, and the hemiacetal selectivity was 95.9%.

Example 13

Using the same preparation steps as in Example 1, using MoO ₂ as the carrier, Cu as the active metal M1, Pt as the active metal M2, and ammonia borane as the hydrogen donor, a bimetallic supported catalyst Cu-Pt/MoO ₂ -NH was prepared.

Using the catalytic activity test method of Example 1, it was determined that the conversion rate of 5-hydroxymethylfurfural in the reaction was 65.2%, the yield of hemiacetal was 63.3%, and the selectivity of hemiacetal was 97.1%.

The performance evaluation results of the bimetal-supported catalysts prepared in Examples 1-13 are shown in Table 1 below.

Table 1 Performance test results of catalysts in Examples 1-5 for catalyzing HMF hemiacetal reaction

Comparative example 1

(1) Prepare the catalyst. The specific steps are as follows:

Mix copper nitrate hexahydrate aqueous solution with a concentration of 0.6M and molybdenum dioxide powder in a ratio of 1:1, stir thoroughly and mix evenly; dry the surface moisture at 80°C and let it stand at room temperature for 12 hours; then grind it into powder. Calculate at 800°C for 5 hours; raise the temperature to 700°C for reduction under normal pressure hydrogen atmosphere for 5 hours to obtain the catalyst Cu/MoO ₂ -H ₂ in which Cu is supported on MoO ₂ .

(2) Catalytic activity test. The specific operation process is the same as in Example 1. The 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 50%, the hemiacetal yield was 9%, and the hemiacetal selectivity was 18%.

Comparative example 2

Using the same preparation steps as Comparative Example 1, using MoO ₂ as the carrier, Co as the active component, and hydrogen as the reducing agent, a catalyst Co/MoO ₂ -H ₂ in which Co is loaded on MoO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 1, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 42%, the hemiacetal yield was 5.2%, and the hemiacetal selectivity was 12.4%.

Comparative example 3

Using the same preparation steps as Comparative Example 1, using MoO ₂ as the carrier, Ni as the active ingredient, and hydrogen as the reducing agent, a catalyst Ni/MoO ₂ -H ₂ in which Ni is loaded on MoO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 1, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 24.2%, the hemiacetal yield was 4.5%, and the hemiacetal selectivity was 18.6%.

Comparative example 4

Using the same preparation steps as Comparative Example 1, using SiO ₂ as the carrier, Cu as the active component, and hydrogen as the reducing agent, a catalyst Cu/SiO ₂ -H ₂ in which Cu is supported on SiO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 1, the conversion rate of 5-hydroxymethylfurfural in the reaction was measured to be 16.9%, the yield of hemiacetal was 0.8%, and the selectivity of hemiacetal was 4.7%.

Comparative example 5

Using the same preparation steps as Comparative Example 1, using CeO ₂ as the carrier, Cu as the active component, and hydrogen as the reducing agent, a catalyst Cu/CeO ₂ -H ₂ containing Cu supported on CeO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 1, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 10.4%, the hemiacetal yield was 1.2%, and the hemiacetal selectivity was 11.5%.

Comparative example 6

Using the same preparation steps as Comparative Example 1, using Al ₂ O ₃ as the carrier, Cu as the active component, and hydrogen as the reducing agent, a catalyst Cu/Al ₂ O ₃ -H ₂ in which Cu is supported on Al ₂ O ₃ was prepared.

Using the catalytic activity test method of Comparative Example 1, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 25.8%, the hemiacetal yield was 5%, and the hemiacetal selectivity was 19.4%.

Comparative example 7

Using the same preparation steps as Comparative Example 1, using In ₂ O ₃ as the carrier, Cu as the active component, and hydrogen as the reducing agent, a catalyst Cu/In ₂ O ₃ -H ₂ in which Cu is supported on In ₂ O ₃ was prepared.

Using the catalytic activity test method of Comparative Example 1, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 5.6%, the hemiacetal yield was 0.4%, and the hemiacetal selectivity was 7.1%.

The performance evaluation results of the catalysts prepared in Comparative Examples 1-7 are shown in Table 2 below.

Table 2 Performance test results of catalysts in Comparative Examples 1-7 catalyzing HMF hemiacetal reaction

Comparative ratio catalyst HMF conversion rate (%) Hemiacetal yield (%) 1 Cu/MoO ₂ -H ₂ 50 9 2 Co/MoO ₂ -H ₂ 42 5.2 3 Ni/MoO ₂ -H ₂ 24.2 4.5 4 Cu/SiO ₂ -H ₂ 16.9 0.8 5 Cu/CeO ₂ -H ₂ 10.3 1.2 6 Cu/Al ₂ O ₃ -H ₂ 25.8 5 7 Cu/In ₂ O ₃ -H ₂ 5.6 0.4

Comparing the catalyst performance test results of Examples and Comparative Examples 1-7, it can be found that when no noble metal component is added, the catalytic performance of the catalyst for the 5-hydroxymethylfurfural hemiacetal reaction is poor, and the 5-hydroxymethylfurfural conversion rate is low. The yield and selectivity of hemiacetal are lower. After adding the second component precious metal, the performance of the catalyst is significantly improved.

Comparative example 8

(1) Prepare the catalyst. The specific steps are as follows:

Mix a certain amount of Pt precursor solution and molybdenum dioxide powder, stir thoroughly and mix evenly; dry the surface moisture at 80°C and let it stand at room temperature for 12 hours; then grind it into powder and calcine at 800°C for 5 hours; The temperature was raised to 700°C for reduction for 5 hours under normal pressure hydrogen atmosphere, and a catalyst Pt/MoO ₂ -H ₂ in which Pt was supported on MoO ₂ was obtained.

(2) Catalytic activity test. The specific operation process is the same as in Example 1. The 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 18%, the hemiacetal yield was 4.7%, and the hemiacetal selectivity was 26%.

Comparative example 9

Using the same preparation steps as Comparative Example 8, using MoO ₂ as the carrier, Pd as the active ingredient, and hydrogen as the reducing agent, a catalyst Pd/MoO ₂ -H ₂ in which Pd is loaded on MoO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 8, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 20%, the hemiacetal yield was 3.7%, and the hemiacetal selectivity was 18.6%.

Comparative example 10

Using the same preparation steps as Comparative Example 8, using MoO ₂ as the carrier, Ru as the active ingredient, and hydrogen as the reducing agent, a catalyst Ru/MoO ₂ -H ₂ containing Ru supported on MoO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 8, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 13.6%, the hemiacetal yield was 3%, and the hemiacetal selectivity was 22.4%.

Comparative example 11

Using the same preparation steps as Comparative Example 8, using MoO ₂ as the carrier, Au as the active ingredient, and hydrogen as the reducing agent, a catalyst Au/MoO ₂ -H ₂ in which Au is supported on MoO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 8, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 12.1%, the hemiacetal yield was 1.7%, and the hemiacetal selectivity was 14.1%.

Comparative example 12

Using the same preparation steps as Comparative Example 8, using MoO ₂ as the carrier, Ir as the active component, and hydrogen as the reducing agent, a catalyst Ir/MoO ₂ -H ₂ in which Ir is loaded on MoO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 8, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 5.5%, the hemiacetal yield was 1%, and the hemiacetal selectivity was 18.3%.

Comparative example 13

Using the same preparation steps as Comparative Example 8, using Al ₂ O ₃ as the carrier, Pt as the active component, and hydrogen as the reducing agent, a catalyst Pt/Al ₂ O ₃ -H ₂ in which Pt is supported on Al ₂ O ₃ was prepared.

Using the catalytic activity test method of Comparative Example 8, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 15%, the hemiacetal yield was 3.5%, and the hemiacetal selectivity was 23.6%.

Comparative example 14

Using the same preparation steps as Comparative Example 8, using In ₂ O ₃ as the carrier, Pt as the active component, and hydrogen as the reducing agent, a catalyst Pt/In ₂ O ₃ -H ₂ in which Pt is supported on In ₂ O ₃ was prepared.

Using the catalytic activity test method of Comparative Example 8, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 11.8%, the hemiacetal yield was 1.7%, and the hemiacetal selectivity was 14.2%.

Comparative example 15

Using the same preparation steps as Comparative Example 8, SiO ₂ is used as the carrier, Pt is the active component, and hydrogen is the reducing agent to prepare the catalyst Pt/SiO ₂ -H ₂ in which Pt is supported on SiO ₂ .

Using the catalytic activity test method of Comparative Example 8, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 4%, the hemiacetal yield was 0.6%, and the hemiacetal selectivity was 15%.

Comparative example 16

Using the same preparation steps as Comparative Example 8, using CeO ₂ as the carrier, Pt as the active component, and hydrogen as the reducing agent, a catalyst Pt/CeO ₂ -H ₂ in which Pt is supported on CeO ₂ was prepared.

Using the catalytic activity test method of Comparative Example 8, the 5-hydroxymethylfurfural conversion rate of the reaction was measured to be 9.6%, the hemiacetal yield was 1.7%, and the hemiacetal selectivity was 17.7%.

The performance evaluation results of the catalysts prepared in Comparative Examples 9-16 are shown in Table 3 below.

Table 3 Performance test results of catalysts in Comparative Examples 8-16 catalyzing HMF hemiacetal reaction

Comparing the catalyst performance test results of Examples and Comparative Examples 8-16, it can be found that when non-noble metal components are not added, the catalytic performance of the catalyst for the 5-hydroxymethylfurfural hemiacetal reaction is poor, and the conversion rate of 5-hydroxymethylfurfural is low. , while the yield and selectivity of hemiacetal are lower. After adding the second component of non-noble metal, the performance of the catalyst is significantly improved.

Although the disclosure of the present invention is as above, the protection scope of the present disclosure is not limited thereto. Those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present disclosure, and these changes and modifications will fall within the protection scope of the present invention.

Claims (10)

1. A method for preparing a bimetal-supported catalyst, which is characterized in that it includes the following steps: S11. Mix the precursor salt of the carrier Y and the active metal M1, use the impregnation method to load the active metal M1 onto the carrier Y, let it stand at room temperature, and dry it to obtain solid A. The carrier Y is a metal. Oxide, the active metal M1 is a non-noble metal; S12. Calcining the solid A in an air atmosphere to obtain solid B; S13. Mix the precursor salt of the active metal M2, the solid B and deionized water, adjust the acidity and alkalinity of the mixed solution, add a hydrogen donor reducing agent, and use the hydrogen donor reduction method to load the active metal M2 to the desired location. On the solid B, the active metal M2 is a precious metal, and the product is filtered and dried to obtain a bimetallic supported catalyst. 2. The preparation method of bimetal-supported catalyst according to claim 1, characterized in that the step S13 specifically includes: mixing the solid B with deionized water, heating and stirring for 1-2 hours; adding hydroxide Adjust the pH of the sodium aqueous solution to 8-9; add the precursor salt of the active metal M2 and stir for 2-5h; add a hydrogen donor reducing agent and continue stirring for 4-6h; filter to obtain the product, wash and dry to obtain the bimetal supported catalyst. 3. The preparation method of the bimetal-supported catalyst according to claim 2, characterized in that the hydrogen donor reducing agent is selected from the group consisting of formic acid, hydrazine hydrate, ammonia borane, ammonium formate, sodium formate, cyclohexene, decahydrogen At least one of naphthalene and tetralin. 4. The preparation method of the bimetal-supported catalyst according to any one of claims 1 to 3, characterized in that the carrier Y is selected from the group consisting of MoO ₂ , Al ₂ O ₃ , In ₂ O ₃ , SiO ₂ , CeO ₂ , At least one of ZnO, the active metal M1 is selected from at least one of Co, Ni, Cu, Sc, Ti, Cr, Mn, Fe, Zn, the active metal M2 is selected from Ru, Pt, Pd, At least one of Au, Ag, Ir, Rh and Os. 5. The preparation method of the bimetallic supported catalyst according to claim 3, characterized in that the mass proportion of the active metal M1 in the bimetallic supported catalyst is 1% to 4%, and the active metal M2 The mass proportion is 0.01% to 0.1%. 6. A method for preparing hemiacetal from furan aldehyde and alcohol, which is characterized in that it includes the following steps: S21. Add the bimetal-supported catalyst prepared by the preparation method according to any one of claims 1 to 5, furan aldehyde and alcoholic organic solvent into the reaction device to form a mixed solution; S22. Pour hydrogen gas into the reaction device to perform a condensation reaction to obtain hemiacetal compounds. 7. The method for preparing hemiacetal from furan aldehyde and alcohol according to claim 6, characterized in that, in the step S22, the reaction temperature is 80°C ~ 140°C, the pressure is 0.5MPa ~ 4MPa, and the time is 0.5h ~8h. 8. The method for preparing hemiacetal from furan aldehyde and alcohol according to claim 6, characterized in that, in the step S21, the molar ratio of the furan aldehyde and the bimetallic supported catalyst is 3500 to 40000: 1. 9. The method for preparing hemiacetal from furan aldehyde and alcohol according to claim 8, characterized in that, in the step S21, the molar concentration of the furan aldehyde in the mixed solution is 0.1M~1M. 10. The method for preparing hemiacetal from furan aldehyde and alcohol according to any one of claims 6 to 9, characterized in that the furan aldehyde is selected from the group consisting of furfural, 5-methylfurfural, 5-hydroxymethylfurfural, 2 , at least one of 5-diformylfuran, 2-furyl ethanol, 5-chloromethylfuran, 4-hydroxymethylfurfural, and 2,5-furandicarbaldehyde, and the alcoholic organic solvent is selected from methanol , at least one of ethanol, ethylene glycol, n-propanol, isopropanol, n-butanol, isobutanol, n-amyl alcohol, iso-amyl alcohol, n-hexanol and iso-hexanol.