Preparation method and application of transition metal alloy catalyst

Abstract

The application discloses a preparation method of a transition metal alloy catalyst, which comprises the following steps: S1, mixing a solution A containing 2,5-dihydroxyterephthalic acid with a solution B containing a transition metal salt and zinc acetate, and performing a hydrothermal reaction to obtain a precursor; the transition metal is at least one selected from nickel, iron, cobalt, copper, manganese, magnesium, zirconium, chromium, molybdenum and cadmium; S2, oxidizing and calcining and reducing and calcining the precursor obtained in the step S1 to obtain the transition metal alloy catalyst. The transition metal alloy is used as an active component, has high activity and high selectivity, can exhibit excellent catalytic performance in the preparation of an aldehyde group hydrogenation reaction, and has very important industrial value.

Description

Technical Field

[0001] This application relates to a method for preparing a transition metal alloy catalyst and its application, belonging to the field of energy chemical preparation technology. Background Technology

[0002] "Biorefining" is the process of sustainably producing valuable chemicals and fuels through the processing of biomass. It typically involves breaking down high-molecular-weight chemicals into platform chemicals and utilizing them to produce chemicals and fuels. Besides obtaining biogas, bio-oils, and biochar through pyrolysis or hydrothermal methods, processes such as depolymerization and hydrodeoxygenation are essential in biomass utilization. Biomass hydrogenation reactions can reduce oxygen content and increase calorific value, making them an important type of reaction in biomass conversion. Selectivity is key to hydrogenation reactions; high selectivity minimizes feedstock consumption, avoids unnecessary separation steps, and produces fewer byproducts. Improving the selectivity for hydrogenation of unsaturated aldehyde C=O groups in organic compounds with C=C bonds has always been a challenging problem.

[0003] Adjusting the electronic structure of metals is an effective way to optimize selective catalysis. This strategy can alter the adsorption and desorption properties of relevant reactants, further changing the catalytic reaction pathway to achieve ideal catalytic performance. For example, through simple heat treatment, Pd with low electron density can be formed at the Pd-carbon interface. δ+ This improves the selective hydrogenation of the C=C bond in cinnamaldehyde. Meanwhile, Pt, with its higher electron density... δ- This can inhibit the adsorption / activation of C=C bonds, thereby promoting the selective hydrogenation of C=O bonds in α,β-unsaturated aldehydes. Constructing intermetallic compounds is an effective means of altering the electronic structure of metals. Summary of the Invention

[0004] According to one aspect of this application, a transition metal alloy catalyst is provided. A MOF precursor is obtained by mixing a solution A containing 2,5-dihydroxyterephthalic acid with water and dimethylformamide as a mixed solvent, and a solution B containing a transition metal salt and zinc acetate, followed by a hydrothermal reaction. This raw material selection and feeding method, compared to existing technologies, solves the problem of difficulty in improving metal dispersion, a problem that has long been unsolved by those skilled in the art. Specifically, the metal dispersion is improved in the MOF precursor due to the isolating effect of organic ligands. Utilizing this principle, the transition metal alloy provided in this application possesses high activity and high selectivity, exhibiting excellent catalytic performance in the hydrogenation reaction of aldehyde compounds to prepare hydroxyl compounds, and has significant industrial value.

[0005] The technical solution adopted in this application is as follows:

[0006] A method for preparing a transition metal alloy catalyst includes the following steps:

[0007] S1. Mix solution A containing 2,5-dihydroxyterephthalic acid with solution B containing transition metal salt and zinc acetate, and perform a hydrothermal reaction to obtain the precursor.

[0008] The transition metal is selected from at least one of nickel, iron, cobalt, copper, manganese, magnesium, zirconium, chromium, molybdenum, and cadmium.

[0009] S2. The precursor obtained in step S1 is subjected to oxidative roasting and reduction roasting to obtain the transition metal alloy catalyst.

[0010] Optionally, in step S1, the molar ratio of transition metal salt, zinc acetate, and 2,5-dihydroxyterephthalic acid is 1:(1-100):(1-100).

[0011] Optionally, in step S1, the molar ratio of transition metal salt, zinc acetate, and 2,5-dihydroxyterephthalic acid is 1:(1-10):(1-10).

[0012] Optionally, in step S1, the molar ratio of transition metal salt, zinc acetate, and 2,5-dihydroxyterephthalic acid is 1:(5-10):(3-6).

[0013] Optionally, the concentration of 2,5-dihydroxyterephthalic acid in solution A is 1-5 mmol / mL, and the concentration of the transition metal in solution B is 0.1-2 mmol / mL.

[0014] Optionally, the transition metal salt is selected from at least one of the nitrate, chloride, acetate, and sulfate salts of the transition metal.

[0015] Optionally, solutions A and B may also independently contain a mixed solvent of water and dimethylformamide.

[0016] Optionally, the volume ratio of water to dimethylformamide in the mixed solvent is 1:1 to 100.

[0017] Optionally, the volume ratio of water to dimethylformamide in the mixed solvent is 1:20 to 50.

[0018] Optionally, the volume ratio of water to dimethylformamide in the mixed solvent is selected from any value among 1:1, 1:5, 1:10, 1:20, 1:29, 1:40, 1:50, 1:60, 1:70, 1:80, 1:90, and 1:100, or any range between the two.

[0019] Optionally, in step S1, the mixing conditions include: mixing solution A and solution B, then ultrasonically treating for 10 to 80 minutes at an ultrasonic frequency of 10 to 100 Hz, followed by stirring for 0.1 to 2 hours at a stirring speed of 50 to 1200 rpm.

[0020] Optionally, in step S1, the conditions for the hydrothermal reaction include: reacting in a closed environment, with a reaction temperature of 60–140°C and a reaction time of 6–72 h.

[0021] Optionally, the reaction temperature of the hydrothermal reaction is selected from any value among 60℃, 70℃, 80℃, 90℃, 100℃, 110℃, 120℃, 130℃, and ~140℃, or any range between the two.

[0022] Optionally, the reaction time is any value among 6h, 8h, 10h, 12h, 18h, 24h, 36h, and 72h, or any range between the two.

[0023] Optionally, in step S2, the conditions for oxidative calcination include: holding at 200–900°C for 1–8 hours in an oxygen-containing atmosphere.

[0024] Optionally, in step S2, the temperature of the oxidative calcination is selected from any value among 200℃, 300℃, 400℃, 500℃, 600℃, 700℃, 800℃, and 900℃, or any range between the two.

[0025] Optionally, in step S2, the temperature of the oxidative calcination is 300–700°C.

[0026] Optionally, in step S2, the holding time for the oxidative calcination is selected from any value among 1h, 2h, 3h, 4h, 5h, 6h, 7h, and 8h, or any range between the two.

[0027] Optionally, in step S2, the oxygen-containing atmosphere is selected from at least one of air and oxygen.

[0028] Optionally, in step S2, the conditions for the reduction calcination include: holding at 100–900°C for 1–8 hours in a hydrogen atmosphere.

[0029] Optionally, in step S2, the reduction calcination temperature is selected from any value among 100℃, 200℃, 300℃, 400℃, 500℃, 600℃, 700℃, 800℃, and 900℃, or a range between any two.

[0030] Optionally, in step S2, the holding time for the reduction calcination is selected from any value among 1h, 2h, 3h, 4h, 5h, 6h, 7h, and 8h, or any range between the two.

[0031] Optionally, the flow rate of the hydrogen gas is 10 to 80 mL / min.

[0032] Optionally, the flow rate of the hydrogen gas is 10 to 30 mL / min.

[0033] Optionally, the reduction calcination conditions may further include heating to the holding temperature at a rate of 1–5 °C / min.

[0034] Optionally, step S1 further includes centrifugation, washing, and drying after hydrothermal reaction to obtain precursor solid powder.

[0035] Optionally, the washing includes washing multiple times with dimethylformamide and methanol.

[0036] Optionally, the drying is performed under vacuum at 40–100°C for 4–12 hours.

[0037] According to another aspect of this application, a transition metal alloy catalyst prepared by the above-described preparation method is provided, characterized in that it comprises a zinc oxide support and a zinc-containing transition metal alloy dispersed on the zinc oxide support.

[0038] Optionally, the zinc-containing transition metal alloy is an alloy formed by at least one of the transition metals and zinc.

[0039] Optionally, the dispersion of the transition metal alloy on the zinc oxide support in the transition metal alloy catalyst is 0.1% to 40%.

[0040] According to another aspect of this application, a transition metal alloy catalyst prepared by the above preparation method is provided, and at least one of the above transition metal alloy catalysts is used in the catalytic hydrogenation of aldehyde compounds to prepare hydroxyl compounds.

[0041] Optionally, the following steps are included:

[0042] A mixture containing a reaction substrate, a hydrogen donor, a transition metal alloy catalyst, and an organic solvent is heated to react and yield a hydroxyl compound.

[0043] The reaction substrate is selected from at least one of aromatic aldehyde compounds and furan aldehyde compounds;

[0044] Optionally, the reaction substrate is selected from at least one of 5-hydroxymethylfurfural and furfural.

[0045] Optionally, the concentration of the reaction substrate is 2–500 mM;

[0046] Optionally, the molar ratio of the reaction substrate to the transition metal alloy catalyst is 10 to 300:1;

[0047] Optionally, the hydrogen donor is selected from at least one of formic acid, 2-butanol, isopropanol, lithium aluminum hydride, sodium borohydride, hydrogen, and diphenylsilane;

[0048] Optionally, the organic solvent is selected from at least one of toluene, ethanol, acetonitrile, ethyl acetate, cyclohexane, 1,4-dioxane, methanol, deionized water, 2-butanol, isopropanol, dichloromethane, N,N-dimethylformamide, tetrahydrofuran, and chloroform.

[0049] Optionally, the mixture further includes a base, wherein the molar ratio of the base to the reaction substrate is 0.5 to 5:1;

[0050] Optionally, the conditions for the heating reaction include: a reaction temperature of 20–200°C, a reaction pressure of 0.1–5 MPa, and a reaction time of 1–36 h.

[0051] The beneficial effects that this application can produce include:

[0052] The method for preparing transition metal alloy catalysts provided in this application yields a transition metal alloy catalyst for the hydrogenation reaction of aldehyde compounds, forming a highly efficient and mild catalytic system for the selective hydrogenation of aldehydes (yield up to 99%). The alloy construction exhibits high selectivity (up to 99%) for the hydrogenation of aldehydes to hydroxyl compounds. Compared to single-metal catalysts, the alloy construction ensures the selectivity of aldehyde hydrogenation. The MOF-derived catalyst preparation method significantly improves the dispersion of the alloy compared to existing impregnation-supported techniques, thereby significantly enhancing the catalytic activity. The preparation method is universally applicable to the preparation of alloy catalysts, exhibiting high alloy dispersion and performance advantages. The transition metals are inexpensive, the synthesis process is simple, and it shows promise for industrial production applications. Attached Figure Description

[0053] Figure 1 The XRD patterns of the catalysts prepared in Example 2, Comparative Example 1, and Comparative Example 2 of this application are shown.

[0054] Figure 2The images show the elemental mapping of the TEM spectra of the catalysts prepared in this application. (a-1), (a-2), and (a-3) are the TEM images at the 100 nm, 10 nm, and 50 nm scales of the catalyst prepared in Example 2, respectively; (b-1), (b-2), and (b-3) are the TEM images at the 100 nm, 10 nm, and 100 nm scales of the catalyst prepared in Comparative Example 1, respectively; and (c-1), (c-2), and (c-3) are the TEM images at the 100 nm, 10 nm, and 200 nm scales of the catalyst prepared in Comparative Example 2, respectively.

[0055] Figure 3 The above are the H2-TPR spectra of the catalysts prepared in Example 2, Comparative Example 1 and Comparative Example 2 of this application. Detailed Implementation

[0056] The present application is described in detail below with reference to the embodiments, but the present application is not limited to these embodiments.

[0057] Unless otherwise specified, all raw materials used in the embodiments of this application were purchased through commercial channels.

[0058] Example 1: Preparation of Cobalt-Zinc Alloy Catalyst

[0059] (1) 2,5-Dihydroxyterephthalic acid (0.003 mol) was dissolved in a mixed solution of 1 mL deionized water and 29 mL dimethylformamide to form solution A. Zn(CH3COO)2·2H2O (0.005 mol) and Co(CH3COO)2·4H2O (0.0005 mol) were also dissolved in a mixed solution of 1 mL deionized water and 29 mL dimethylformamide to form solution B. Solutions A and B were then mixed and stirred at room temperature for 20 min, then transferred to the lining of a hydrothermal reactor and heated at 120 °C for 12 h. After cooling to room temperature, the resulting reaction solution was centrifuged, washed several times with DMF and methanol, and dried under vacuum at 50 °C for 12 h to obtain a yellow powder sample, labeled as 10CoZn-MOF.

[0060] (2) 10CoZn-MOF was calcined at 400℃ for 5h in air atmosphere. The calcined catalyst was a dark gray powder. The calcined oxide material was placed in a tube furnace and H2 gas was introduced at a flow rate of 20mL / min. The temperature was increased to 500℃ at 2℃ / min and held for 3h to obtain the catalyst labeled as 10CoZn@ZnO.

[0061] Example 2: Preparation of Nickel-Zinc Alloy Catalyst

[0062] (1) 2,5-Dihydroxyterephthalic acid (0.003 mol) was dissolved in a mixed solution of 1 mL deionized water and 29 mL dimethylformamide to form solution A. Zn(CH3COO)2·2H2O (0.005 mol) and Ni(CH3COO)2·6H2O (0.0005 mol) were also dissolved in a mixed solution of 1 mL deionized water and 29 mL dimethylformamide to form solution B. Solutions A and B were then mixed and stirred at room temperature for 20 min, then transferred to the lining of a hydrothermal reactor and heated at 120 °C for 12 h. After cooling to room temperature, the resulting reaction solution was centrifuged, washed several times with DMF and methanol, and dried under vacuum at 50 °C for 12 h to obtain a yellow powder sample, labeled as 10NiZn-MOF.

[0063] (2) 10NiZn-MOF was calcined at 400℃ for 5h in air atmosphere. The calcined catalyst was a dark gray powder. The calcined oxide material was placed in a tube furnace and H2 gas was introduced at a flow rate of 20mL / min. The temperature was increased to 500℃ at 2℃ / min and held for 3h to obtain the catalyst labeled as 10NiZn@ZnO.

[0064] Example 3: Preparation of copper-zinc alloy catalyst

[0065] (1) 2,5-Dihydroxyterephthalic acid (0.003 mol) was dissolved in a mixed solution of 1 mL deionized water and 29 mL dimethylformamide to form solution A. Zn(CH3COO)2·2H2O (0.005 mol) and Cu(CH3COO)2·H2O (0.0005 mol) were also dissolved in a mixed solution of 1 mL deionized water and 29 mL dimethylformamide to form solution B. Solutions A and B were then mixed and stirred at room temperature for 20 min, then transferred to the lining of a hydrothermal reactor and heated at 120 °C for 12 h. After cooling to room temperature, the resulting reaction solution was centrifuged, washed several times with DMF and methanol, and dried under vacuum at 50 °C for 12 h to obtain a yellow powder sample, labeled as 10CuZn-MOF.

[0066] (2) 10CuZn-MOF was calcined at 400℃ for 5h in air atmosphere. The calcined catalyst was a dark gray powder. The calcined oxide material was placed in a tube furnace and H2 gas was introduced at a flow rate of 20mL / min. The temperature was increased to 500℃ at 2℃ / min and held for 3h to obtain the catalyst labeled as 10CuZn@ZnO.

[0067] Example 4: Preparation of manganese-zinc alloy catalyst

[0068] (1) 2,5-Dihydroxyterephthalic acid (0.003 mol) was dissolved in a mixed solution of 1 mL deionized water and 29 mL dimethylformamide to form solution A. Zn(CH3COO)2·2H2O (0.005 mol) and Mn(CH3COO)2·4H2O (0.0005 mol) were also dissolved in a mixed solution of 1 mL deionized water and 29 mL dimethylformamide to form solution B. Solutions A and B were then mixed and stirred at room temperature for 20 min, and then transferred to the lining of a hydrothermal reactor. The mixture was heated at 120 °C for 12 h. After cooling to room temperature, the resulting reaction solution was centrifuged, washed several times with DMF and methanol, and dried under vacuum at 50 °C for 12 h to obtain a yellow powder sample, labeled as 10MnZn-MOF.

[0069] (2) 10MnZn-MOF was calcined at 400℃ for 5h in air atmosphere. The calcined catalyst was a dark gray powder. The calcined oxide material was placed in a tube furnace and H2 gas was introduced at a flow rate of 20mL / min. The temperature was increased to 500℃ at 2℃ / min and held for 3h to obtain the catalyst labeled as 10MnZn@ZnO.

[0070] Example 5: Preparation of another nickel-zinc alloy catalyst

[0071] The steps and conditions are the same as in Example 2, except that in step (1), the amount of Ni(CH3COO)2·6H2O is 0.00025mol, and a yellow powder sample is obtained, which is labeled as 5NiZn-MOF; (2) the catalyst is labeled as 5NiZn@ZnO.

[0072] Example 6: Preparation of another nickel-zinc alloy catalyst

[0073] The steps and conditions are the same as in Example 2, except that in step (1), the amount of Ni(CH3COO)2·6H2O is 0.001 mol, and a yellow powder sample is obtained, which is labeled as 20NiZn-MOF; (2) the catalyst is labeled as 20NiZn@ZnO.

[0074] Example 7: Preparation of another nickel-zinc alloy catalyst

[0075] The steps and conditions are the same as in Example 2, except that in step (1), the amount of Zn(CH3COO)2·2H2O is 0.0015mol and the amount of Ni(CH3COO)2·6H2O is 0.0035mol, and a yellow powder sample is obtained, which is labeled as 70NiZn-MOF; (2) the catalyst is labeled as 70NiZn@ZnO.

[0076] Example 8: Catalytic hydrogenation of 5-hydroxymethylfurfural to synthesize 2,5-furandiethanol

[0077] The transition metal alloy catalysts prepared in Examples 1-7 were applied to the hydrogenation of 5-hydroxymethylfurfural, and the specific steps are as follows:

[0078] 0.5 mmol of 5-hydroxymethylfurfural, 0.1 g of catalyst, and 20 mL of ethanol were added to an autoclave and stirred until homogeneous. The reactor was then repeatedly purged with 2 MPa H2 five times to displace the air inside, followed by a fresh 2 MPa H2 purging. The reactor parameters were set as follows: reaction temperature 100 °C and stirring rate 500 rpm. After the reaction, the reactor was rapidly cooled with tap water to separate the reaction solution from the catalyst. Quantitative analysis was performed using an Agilent GC-7890B gas chromatograph equipped with a flame ionization detector (FID) and a DB-WAX capillary column (J&W, 30 m, 0.25 mm i.d.). During the analysis, the vaporization chamber and detector temperatures were maintained at 220 °C. After injection, the column oven was first held at 45 °C for 5 min, then increased to 220 °C at a rate of 25 °C / min and held for 5 min.

[0079] Under the above reaction conditions, the reaction was carried out for 2 hours. The hydrogenation performance of the transition metal alloy catalysts prepared in Examples 1-7 for the hydrogenation of 5-hydroxymethylfurfural is shown in Table 1. The results show that 10NiZn@ZnO obtained in Example 1 has excellent ability to hydrogenate 5-hydroxymethylfurfural to 2,5-furandimethyl. Under the above reaction conditions, a 2-hour reaction yield of 89% 2,5-furandimethyl was obtained. Co, Cu, and Mn-based alloy catalysts all showed slightly lower activity than Ni in the hydrogenation of 5-hydroxymethylfurfural to 2,5-furandimethyl, yielding BHMF yields of 81%, 75%, and 79%, respectively. However, all exhibited BHMF selectivity greater than 98%, demonstrating that the alloy catalysts can guarantee the catalytic selectivity for aldehyde hydrogenation. 20NiZn@ZnO exhibits even higher catalytic activity.

[0080] Table 1 Comparison of the performance of transition metal alloy catalysts in the hydrogenation of 5-hydroxymethylfurfural

[0081]

[0082]

[0083] Comparative Example 1: Preparation of Supported Nickel-Zinc Alloy Catalyst

[0084] (1) 0.003 mol of 2,5-dihydroxyterephthalic acid was dissolved in a mixture of 1 mL of deionized water and 29 mL of dimethylformamide to form solution A. 0.005 mol of Zn(CH3COO)2·2H2O was also dissolved in a mixture of 1 mL of deionized water and 29 mL of dimethylformamide to form solution B. Solutions A and B were then mixed and stirred at room temperature for 20 min before being transferred to the lining of a hydrothermal reactor and heated at 120 °C for 12 h. After cooling to room temperature, the resulting reaction solution was centrifuged, washed several times with DMF and methanol, and dried under vacuum at 50 °C for 12 h to obtain a yellow powder sample, labeled as Zn-MOF.

[0085] (2) Zn-MOF was calcined at 400℃ for 5 hours in air, and the calcined catalyst was a white powder ZnO. 0.38 g of Ni(NO3)2·6H2O was dissolved in a small amount of deionized water, and 1 g of ZnO was immersed in the aqueous solution. The mixture was ultrasonically treated for 1 hour, placed at room temperature for 24 hours, dried in an oven at 80℃ for 24 hours, and ground into powder. The calcined oxide material was placed in a tube furnace, and H2 gas was introduced at a flow rate of 20 mL / min. The temperature was increased to 500℃ at 2℃ / min and held for 3 hours to obtain a catalyst labeled 7.5Ni / ZnO(MOF).

[0086] Comparative Example 2: Preparation of Supported Nickel-Zinc Alloy Catalyst

[0087] 0.38 g of Ni(NO3)2·6H2O was dissolved in a small amount of deionized water. 1 g of commercial ZnO was immersed in the aqueous solution, ultrasonicated for 1 h, left at room temperature for 24 h, dried in an oven at 80 °C for 24 h, and then ground into powder. The calcined oxide material was placed in a tube furnace, and H2 gas was introduced at a flow rate of 20 mL / min. The temperature was increased to 500 °C at 2 °C / min and held for 3 h to obtain 7.5Ni / ZnO(com).

[0088] Test Example 1

[0089] Figure 1 The XRD patterns of the catalysts prepared in Example 2, Comparative Example 1, and Comparative Example 2 demonstrate that NiZn alloys were successfully prepared in all cases. The diffraction peak intensities of the NiZn alloys in the examples are lower than those in the comparative examples, indicating that the NiZn alloys prepared by the MOF derivatization method in Example 2 are small in size and uniformly dispersed. Figure 2 The TEM images of Example 2, Comparative Example 1, and Comparative Example 2 further confirm that the particles are NiZn alloys, and in the TEM image of Example 2, the Ni particles are smaller and more uniformly dispersed. Figure 3The H2-TPR results for Examples 2, 1, and 2 show that no reduction peak of elemental Ni was obtained in Example 2, and the reduction temperature of NiZn was lower than that of NiZn in the comparative example. This demonstrates that the interaction between Ni and Zn is strong and the Ni dispersion is high in the MOF-derived catalysts obtained in the examples. Table 2 compares the physicochemical properties of the catalysts in Examples 2, 1, and 2. The Ni content of the three catalysts is approximately 7.5%, but the Ni dispersion varies greatly. The catalyst prepared by the MOF-derived method in Example 1 has a significantly higher dispersion.

[0090] Table 2 Comparison of physicochemical properties of catalysts

[0091]

[0092] Ni dispersion was tested using a temperature-programmed chemisorption analyzer (BELCAT MicrotracBEL, Japan). The specific test procedure for CO pulse adsorption was as follows: 100 mg of unreduced sample was heated from room temperature to 500 °C at a programmed rate of 3 °C / min under a pure H2 atmosphere and held for 2 h. He gas was then purged for 1 h at a rate of 50 mL / min. After cooling to 50 °C, CO was introduced for titration. The number and dispersion of effective Ni active sites were automatically estimated by analyzing the difference in CO levels before and after CO introduction.

[0093] Example 9: Catalytic hydrogenation of 5-hydroxymethylfurfural to synthesize 2,5-furandiethanol

[0094] Example 2: The transition metal alloy catalysts prepared in Comparative Examples 1 and 2 were applied to the hydrogenation of 5-hydroxymethylfurfural, and the specific steps are as follows:

[0095] 0.5 mmol of 5-hydroxymethylfurfural, 0.1 g of catalyst, and 20 mL of ethanol were added to an autoclave and stirred until homogeneous. The reactor was then repeatedly purged with 2 MPa H2 five times to displace the air inside, followed by a fresh 2 MPa H2 purging. The reactor parameters were set as follows: reaction temperature 100 °C and stirring rate 500 rpm. After the reaction, the reactor was rapidly cooled with tap water to separate the reaction solution from the catalyst. Quantitative analysis was performed using an Agilent GC-7890B gas chromatograph equipped with a flame ionization detector (FID) and a DB-WAX capillary column (J&W, 30 m, 0.25 mm i.d.). During the analysis, the vaporization chamber and detector temperatures were maintained at 220 °C. After injection, the column oven was first held at 45 °C for 5 min, then increased to 220 °C at a rate of 25 °C / min and held for 5 min.

[0096] The transition metal alloy catalysts prepared in Examples 2, 1, and 2, respectively, exhibited excellent hydrogenation performance in the hydrogenation of 5-hydroxymethylfurfural, as shown in Table 3. The results indicate that the NiZn@ZnO catalyst obtained in Example 2 possesses excellent ability to synthesize 2,5-furandiethanol from 5-hydroxymethylfurfural. Under the above reaction conditions, a 99% yield of 2,5-furandiethanol was obtained after 4 hours of reaction. The supported catalysts obtained in the comparative examples showed lower hydrogenation capacity for 5-hydroxymethylfurfural, but all demonstrated BHMF selectivity greater than 98%, proving that the alloy catalysts can guarantee the catalytic selectivity for aldehyde hydrogenation.

[0097] Table 3 Comparison of the performance of transition metal alloy catalysts in the hydrogenation of 5-hydroxymethylfurfural

[0098]

[0099] The above description is merely a few embodiments of this application and is not intended to limit this application in any way. Although this application discloses preferred embodiments as described above, it is not intended to limit this application. Any changes or modifications made by those skilled in the art without departing from the scope of the technical solution of this application using the disclosed technical content are equivalent to equivalent implementation cases and fall within the scope of the technical solution.

Claims

1. An application of a transition metal alloy catalyst, characterized in that, The catalyst is used for the hydrogenation of 5-hydroxymethylfurfural to synthesize 2,5-furandiethanol; the catalyst comprises a zinc oxide support and a zinc-containing transition metal alloy dispersed on the zinc oxide support; the catalyst preparation method includes the following steps: S1. A solution A containing 2,5-dihydroxyterephthalic acid is mixed with a solution B containing a transition metal salt and zinc acetate, and a hydrothermal reaction is carried out to obtain a precursor; the solution A and the solution B also independently contain a mixed solvent of water and dimethylformamide; the volume ratio of water to dimethylformamide in the mixed solvent is selected from a range between 1:20 and 1:

40. The transition metal is selected from at least one of nickel, cobalt, copper, and manganese; in step S1, the molar ratio of the transition metal salt, zinc acetate, and 2,5-dihydroxyterephthalic acid is 1:(1~100):(1~100); S2. The precursor obtained in step S1 is subjected to oxidative roasting and reduction roasting to obtain the transition metal alloy catalyst.

2. The application according to claim 1, characterized in that, The concentration of 2,5-dihydroxyterephthalic acid in solution A is 1~5 mmol / mL, and the concentration of the transition metal in solution B is 0.1~2 mmol / mL; The transition metal salt is selected from at least one of the nitrate, chloride, acetate, and sulfate salts of the transition metal.

3. The application according to claim 1, characterized in that, The volume ratio of water to dimethylformamide in the mixed solvent is 1:

29.

4. The application according to claim 1, characterized in that, In step S1, the mixing conditions include: mixing solution A and solution B, ultrasonic treatment for 10-80 minutes at an ultrasonic frequency of 10-100 Hz, and then stirring for 0.1-2 hours at a stirring speed of 50-1200 rpm.

5. The application according to claim 1, characterized in that, In step S1, the conditions for the hydrothermal reaction include: reacting in a closed environment, with a reaction temperature of 60~140℃ and a reaction time of 6~72h.

6. The application according to claim 1, characterized in that, In step S2, the conditions for the oxidative calcination include: holding at 200~900℃ for 1~8 hours in an oxygen-containing atmosphere.

7. The application according to claim 1, characterized in that, In step S2, the conditions for the reduction calcination include: in a hydrogen atmosphere, maintaining the temperature at 100~900℃ for 1~8 hours.

8. The application according to claim 1, characterized in that, Includes the following steps: A mixture containing a reaction substrate, a hydrogen donor, a transition metal alloy catalyst, and an organic solvent is heated to react and yield a hydroxyl compound. The concentration of the reaction substrate is 2~500mM; The molar ratio of the reaction substrate to the transition metal alloy catalyst is 10~300:

1.

9. The application according to claim 8, characterized in that, The hydrogen donor is selected from at least one of formic acid, lithium aluminum hydride, sodium borohydride, and hydrogen.

10. The application according to claim 8, characterized in that, The conditions for the heating reaction include: a reaction temperature of 20~200℃, a reaction pressure of 0.1~5MPa, and a reaction time of 1~36h.

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