Method for preparing 2, 5-dihydroxymethyl tetrahydrofuran from 5-hydroxymethylfurfural

Abstract

The invention belongs to the field of catalytic hydrogenation reaction, and provides a method for preparing 2, 5-dimethyloltetrahydrofuran from 5-hydroxymethylfurfural, which comprises the following steps: in the presence of a metal catalyst and an alcohol solvent, contacting 5-hydroxymethylfurfural with hydrogen to carry out hydrogenation reaction to form 2, 5-dimethyloltetrahydrofuran and optional 2, 5-dimethyloltetrahydrofuran. A reaction product of 1, 5-furandimethanol; wherein the metal catalyst is a nickel-aluminum-lanthanum three-way catalyst. The method disclosed by the invention can be used for efficiently synthesizing the 2, 5-dimethyloltetrahydrofuran.

Description

Technical Field

[0001] The invention belongs to the field of catalytic hydrogenation reaction, and specifically provides a method for preparing 2,5-dihydroxymethyltetrahydrofuran from 5-hydroxymethylfurfural. Background Art

[0002] Biomass is widely distributed and abundant in nature. It is an environmentally friendly, clean, and renewable resource that has important practical significance in alleviating the shortage of fossil fuel resources and environmental pollution. In recent years, the conversion of biomass resources into platform chemicals has attracted widespread attention from researchers.

[0003] Among these platform compounds, 5-hydroxymethylfurfural (HMF) is considered one of the most important biomass-based platform molecules and a key precursor for the preparation of fine chemicals, key pharmaceutical intermediates, functional polyesters, solvents, and liquid fuels. Through reactions such as hydrogenation and hydrodeoxygenation, HMF can be derived into a variety of high-value-added chemicals, such as 2,5-furan dimethanol (BHMF), 2,5-dihydroxymethyltetrahydrofuran (BHMTHF), and 2,5-dimethylfuran (DMF). BHMTHF, due to its unique saturated tetrahydrofuran ring structure, exhibits particularly important application value. For example, a) it can serve as a key intermediate for the synthesis of high-value pharmaceutical molecules and agrochemicals; b) it can be used as a component of biofuels because of its superior energy density and combustion performance compared to some biofuel precursors and its good compatibility with existing fuel infrastructure; and c) it can be used as a monomer or intermediate to prepare polymers, where its saturated ring structure imparts superior stability to the polymers. However, despite the broad prospects of BHMTHF, its efficient and selective synthesis still faces huge challenges, and the synthesis efficiency is generally low. This is mainly due to the complex molecular structure of HMF, which easily produces a variety of mixed products including BHMF, DMF and etherification by-products during the hydrogenation process.

[0004] Currently, the catalytic hydrogenation of HMF is primarily carried out in the presence of precious metal catalysts (such as Pd, Pt, and Ru). While precious metal catalysts offer high hydrogenation activity, their strong hydrogenation capacity often makes controlling the depth of hydrogenation difficult. In the presence of precious metal catalysts and a hydrogen atmosphere, the aldehyde groups of HMF molecules are reduced to alcohol groups, producing BHMF. Further hydrogenation completely saturates the C=C bonds on the furan ring, producing BHMTHF. However, the furan ring is more susceptible to ring opening or excessive hydrogenolysis of the hydroxymethyl group, resulting in undesirable products. This results in low selectivity and yield of BHMTHF. Furthermore, the high cost of precious metal catalysts severely hinders the promotion of green BHMTHF production using HMF as a raw material. Some studies have also focused on non-precious metal catalysts (such as Ni, Fe, Cu, etc.), but current non-precious metal catalysts generally have relatively low activity and are difficult to simultaneously activate aldehyde groups and furan rings under mild conditions. Their catalytic activity, BHMTHF synthesis efficiency and selectivity are much lower than those of precious metals, or the reaction conditions required to pursue high BHMTHF yields are more stringent (manifested in the reaction time being too long, the temperature being too high, the hydrogen pressure being too high, etc.). Summary of the Invention

[0005] In view of the above problems existing in the prior art, the present invention aims to provide a method for preparing 2,5-dihydroxymethyltetrahydrofuran from 5-hydroxymethylfurfural. The method of the present invention can efficiently synthesize 2,5-dihydroxymethyltetrahydrofuran.

[0006] To achieve the above-mentioned object, the present invention provides a method for preparing 2,5-dihydroxymethyltetrahydrofuran from 5-hydroxymethylfurfural, comprising: contacting 5-hydroxymethylfurfural with hydrogen in the presence of a metal catalyst and an alcohol solvent to carry out a hydrogenation reaction to form a reaction product containing 2,5-dihydroxymethyltetrahydrofuran and optionally 2,5-furan dimethanol; wherein the metal catalyst is a nickel-aluminum-lanthanum ternary catalyst, and the molar ratio of Ni, Al and La is (8-12):(5-12):(1-2).

[0007] In some embodiments, the metal catalyst is prepared by using metal salts including nickel salts, aluminum salts and lanthanum salts to generate a catalyst precursor through a precipitation method, followed by calcination and reduction treatment.

[0008] In the hydrogenation reaction of the present invention, the nickel-aluminum-lanthanum ternary catalyst (hereinafter referred to as "NiAlLa") used is a non-precious metal catalyst. The catalyst exhibits high hydrogenation catalytic activity in the catalytic reaction of 5-hydroxymethylfurfural under the condition of alcohol as solvent. Under mild conditions and in a short time, it can not only achieve a high conversion rate of the reaction, but also improve the selectivity and yield of the target product 2,5-dihydroxymethyltetrahydrofuran.

[0009] Additional aspects and advantages of the present invention will be set forth in part in the description which follows and, in part, will be obvious from the description which follows, or may be learned by practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The above and / or additional aspects and advantages of the present invention will become apparent and readily understood from the description of the embodiments with reference to the following drawings, in which:

[0011] Figure 1 The XRD patterns of the catalysts of Preparation Examples 1 to 5 and Comparative Preparation Examples 3 to 6 are shown;

[0012] Figure 2 This is the gas chromatogram of the product liquid prepared in Example 1. DETAILED DESCRIPTION

[0013] The embodiments of the present invention are described in detail below. The embodiments described below are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0014] The "ranges" disclosed herein are defined in terms of lower and / or upper limits, with a given range being defined by selecting a lower limit and / or an upper limit. Ranges defined in this manner may be inclusive or exclusive of the end values ​​and may be combined arbitrarily, i.e., any lower limit may be combined with any upper limit to form an unspecified range, and any lower limit may be combined with any other lower limit to form an unspecified range, and similarly, any upper limit may be combined with any other upper limit to form an unspecified range. In addition, each separately disclosed point or single value may itself be combined as a lower limit or upper limit with any other point or single value, or with other lower limits or upper limits to form an unspecified range.

[0015] Unless otherwise specified, all embodiments and optional embodiments of the present invention can be combined with each other to form new technical solutions, and such technical solutions should be considered to be included in the disclosure of the present invention.

[0016] The present invention provides a method for preparing 2,5-dihydroxymethyltetrahydrofuran from 5-hydroxymethylfurfural, comprising: contacting 5-hydroxymethylfurfural (HMF) with hydrogen in the presence of a metal catalyst and an alcohol solvent to carry out a hydrogenation reaction to form a reaction product containing 2,5-dihydroxymethyltetrahydrofuran (BHMTHF) and optionally 2,5-furan dimethanol (BHMF).

[0017] In the present invention, the metal catalyst is a nickel-aluminum-lanthanum ternary catalyst (NiAlLa), wherein Ni has hydrogenation activity and can promote the hydrogenation reaction of 5-hydroxymethylfurfural, Al can adjust the acidity and alkalinity of the catalyst, and La, as an auxiliary agent, is conducive to stabilizing the structure. The three act synergistically to promote the efficient synthesis of BHMTHF. In the nickel-aluminum-lanthanum ternary catalyst, the molar ratio of Ni, Al and La is (8-12): (5-12): (1-2), for example, 10:10:1, 10:10:2, 10:8:1, 8:8:1, 8:7:1, 9:8:1, 8:6:1, 10:11:1, 12:10:1, 11:9:1, 12:8:1, 8:12:1, 10:8:1, 8:10:1, etc.

[0018] In order to avoid the possibility that the acidity of the catalyst is weakened due to too low Al content and that the La content is too high, which will cover the active sites of Ni or affect the surface acidity and alkalinity and inhibit hydrogenation, preferably, in the nickel-aluminum-lanthanum ternary catalyst, based on the total amount of Ni, Al and La, the molar content of Ni is 40% to 60%, for example, 40%, 45%, 47%, 48%, 50%, 52%, 55%, 60%, etc.; the molar content of Al is 32% to 52%, for example, 32%, 40%, 45%, 48%, 50%, 51%, etc.; the molar content of La is 4% to 8%, for example, 4%, 4.5%, 5%, 6%, 8%, etc.

[0019] In some embodiments, the metal catalyst is prepared by using metal salts including nickel salts, aluminum salts and lanthanum salts to generate a catalyst precursor through a precipitation method, followed by calcination and reduction treatment.

[0020] According to some specific embodiments, the method for preparing the metal catalyst (i.e., nickel-aluminum-lanthanum ternary catalyst) comprises the following steps:

[0021] 1) subjecting metal salts including nickel salts, aluminum salts and lanthanum salts to a precipitation reaction with a precipitant in water and aging the reaction to obtain a solid-liquid product;

[0022] 2) performing solid-liquid separation on the solid-liquid product, and washing, drying and calcining the obtained solid;

[0023] 3) reducing the calcined product obtained in step 2) in a hydrogen-containing atmosphere to obtain a metal catalyst.

[0024] In the present invention, the relative molar ratio of each metal element in the catalyst can be calculated based on the molar feed amount of different metal salts. The present invention does not particularly limit the type of metal salt, as long as it can form a precipitate with the precipitant. Generally, various water-soluble salts can be selected, for example, one or more of nitrates, chlorides, and sulfates can be selected. As some preferred embodiments, the nickel salt is nickel nitrate, the aluminum salt is aluminum nitrate, and the lanthanum salt is lanthanum chloride and / or lanthanum nitrate. In addition, the metal salt should be understood in a broad sense, covering both anhydrous metal salts and various metal salt hydrates. For example, nickel nitrate can be anhydrous nickel nitrate (Ni(NO3)2), or nickel nitrate hydrate (such as Ni(NO3)2·6H2O), aluminum nitrate can be anhydrous aluminum nitrate (Al(NO3)3), or aluminum nitrate hydrate (such as Al(NO3)3·9H2O), and lanthanum chloride can be anhydrous lanthanum chloride (LaCl3), or lanthanum chloride hydrate (such as LaCl3·7H2O). The precipitant can be selected from alkaline precipitants, preferably sodium carbonate.

[0025] In step 1), in order to allow the metal salts to fully react to form a precipitate, the amount of the precipitant is preferably excessive. According to some embodiments, the molar ratio of the total amount of the metal salts (i.e., nickel salt, aluminum salt, and lanthanum salt) to the amount of the precipitant is 1:(1.5-5), for example, 1:1.5, 1:1.8, 1:2, 1:2.5, 1:3, 1:4, 1:5, etc.

[0026] In some embodiments, the conditions of the precipitation reaction may include: a temperature of 15 to 40° C., such as room temperature; and a reaction time of 2 to 6 hours, such as 2 hours, 3 hours, 4 hours, 4.5 hours, 5 hours, 6 hours, etc. To further increase the specific surface area and active site density of the catalyst, preferably, step 1) includes:

[0027] 1-1) adding dropwise a precipitant aqueous solution to a metal salt aqueous solution containing a nickel salt, an aluminum salt, and a lanthanum salt to perform a precipitation reaction;

[0028] 1-2) The product obtained in step 1-1) is aged to obtain a solid-liquid product.

[0029] The concentration of the precipitant aqueous solution can be 0.8 to 1.5 mol / L, such as 0.8 mol / L, 1 mol / L, 1.2 mol / L, 1.3 mol / L, 1.5 mol / L, etc.; the concentration of the metal salt aqueous solution can be 0.2 to 2 mol / L, such as 0.4 mol / L, 0.5 mol / L, 0.7 mol / L, 1 mol / L, 1.2 mol / L, 1.5 mol / L, 1.8 mol / L, etc. The droplet rate of the precipitant aqueous solution can be 0.5 to 2 mL / min. Preferably, the volume ratio of the metal salt aqueous solution to the precipitant aqueous solution is (0.8 to 1.2):1, such as 0.8:1, 1:1, 1.1:1, 1.2:1, etc.

[0030] In step 1), aging treatment can make the precipitated crystal particles more uniform and stable. According to some embodiments, the aging conditions may include: a temperature of 50 to 80° C., such as 50° C., 60° C., 65° C., 70° C., 75° C., 80° C., etc.; and an aging time of 8 to 15 hours, such as 8 hours, 9 hours, 10 hours, 12 hours, 13 hours, 15 hours, etc.

[0031] The solid-liquid separation in step 2) is not particularly limited in the present invention, as long as the solid can be separated. For example, but not limited to, filtration can be used for solid-liquid separation. The washing is intended to remove impurities (e.g., unreacted precipitant) in the solid product. For example, water can be used for multiple washings until the final washing liquid is neutral.

[0032] In step 2), the drying is intended to remove moisture from the product, and the drying can be performed in an oven, for example. According to some embodiments, the drying temperature can be 90 to 130° C., for example, 90° C., 95° C., 100° C., 110° C., 120° C., 125° C., 130° C., etc.; and the drying time is 3 to 10 hours, for example, 3 hours, 5 hours, 7 hours, 8 hours, 9 hours, 10 hours, etc.

[0033] In step 2), the precipitate can be converted into a metal oxide by calcination. The calcination can usually be carried out in an oxygen-containing atmosphere, which can be, for example, oxygen or air, preferably air. According to some embodiments, the calcination temperature can be 350-600°C, for example, 400°C, 450°C, 500°C, 520°C, 550°C, 600°C, etc.; the calcination time can be 3-8 hours, for example, 3 hours, 4 hours, 5 hours, 7 hours, 8 hours, etc. In addition, the calcination can be carried out in a muffle furnace.

[0034] According to some specific implementations, step 2) includes the following operations:

[0035] 2-1) filtering the solid-liquid product, washing the obtained solid (i.e., filter cake) with water, and drying;

[0036] 2-2) Grinding and sieving the product obtained in step 2-1) to obtain an undersize, which is then calcined. Preferably, the particle size of the metal catalyst is not greater than 100 mesh by sieving.

[0037] In step 3), the catalyst can be activated by reducing the calcined product. The reduction is performed in a hydrogen-containing atmosphere, which can be, for example, hydrogen or a mixture of hydrogen and an inert gas. Preferably, the hydrogen-containing atmosphere is a mixture of hydrogen and nitrogen, and the volume content of hydrogen in the mixture is 2% to 8%, for example, 2%, 5%, 8%, etc.

[0038] In some embodiments, the reduction temperature may be 400-600° C., for example, 400° C., 500° C., 550° C., 600° C., etc. Preferably, the reduction temperature is 500-600° C. The reduction time may be 3-7 hours, for example, 4 hours, 5 hours, 6 hours, 7 hours, etc.

[0039] In the present invention, the hydrogenation reaction of 5-hydroxymethylfurfural can be carried out in a high-pressure reactor under stirring conditions. The stirring speed can be, for example, 300 to 700 rpm, such as 350 rpm, 450 rpm, 500 rpm, 550 rpm, 600 rpm, etc.

[0040] In some embodiments, the temperature of the hydrogenation reaction can be 90 to 140° C., for example, 90° C., 100° C., 110° C., 125° C., 120° C., 130° C., 140° C., etc. The reaction time can be selected according to the reaction temperature. When the BHMTHF yield is equivalent, the reaction time is generally extended as the reaction temperature decreases. The reaction time can be 0.5 to 6 hours, for example, 0.5 hours, 1 hour, 1.5 hours, 2 hours, 3 hours, 5 hours, 6 hours, preferably 1 to 5 hours.

[0041] As some specific examples, the temperature of the hydrogenation reaction is 120° C., and the reaction time is 1.5 h. As some other specific examples, the temperature of the hydrogenation reaction is 90° C., and the reaction time is 4 to 5 h.

[0042] In the present invention, in the hydrogenation reaction, the pressure of hydrogen may be 2 to 10 MPa, for example, 2 MPa, 3 MPa, 4 MPa, 5 MPa, 6 MPa, 8 MPa, 10 MPa, etc., preferably 2 to 5 MPa.

[0043] In the present invention, the amount of the metal catalyst can be selected according to the amount of the reactant 5-hydroxymethylfurfural. In some embodiments, the mass ratio of the metal catalyst to 5-hydroxymethylfurfural can be (0.25-1.5):1, for example, 0.25:1, 0.5:1, 0.75:1, 1:1, 1.2:1, 1.3:1, 1.5:1, etc. In particular, since the metal catalyst has a high catalytic hydrogenation activity, a high BHMTHF yield can be achieved with a smaller amount. In order to increase the BHMTHF yield while reducing costs, the mass ratio of the metal catalyst to 5-hydroxymethylfurfural is preferably (0.5-1):1.

[0044] In the present invention, the hydrogenation reaction is carried out in the presence of a solvent, and the solvent is an alcohol solvent. Furthermore, the alcohol solvent can be selected from lower alcohols having 1 to 4 carbon atoms, specifically at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol, and sec-butanol. Preferably, the alcohol solvent is sec-butanol. Compared to other lower alcohols, using sec-butanol as a solvent can effectively increase the hydrogenation rate and selectivity for BHMTHF in the product.

[0045] In some embodiments, the amount of the alcohol solvent used is such that the concentration of 5-hydroxymethylfurfural is 1 to 150 g / L, for example, 1 g / L, 2 g / L, 3 g / L, 5 g / L, 10 g / L, 20 g / L, 35 g / L, 50 g / L, 75 g / L, 150 g / L, etc.

[0046] In the present invention, the reaction product generated by the hydrogenation reaction of 5-hydroxymethylfurfural is mainly 2,5-dihydroxymethyltetrahydrofuran (BHMTHF). Optionally, the reaction product also includes 2,5-furan dimethanol (BHMF). Preferably, the molar content of BHMTHF in the reaction product is not less than 80%.

[0047] In the present invention, after the hydrogenation reaction is completed, the method preferably further comprises: centrifuging the reaction system to recover the metal catalyst therein. In addition, the supernatant obtained by centrifugation contains reaction products such as BHMTHF and an alcohol solvent.

[0048] The following embodiments of the present invention are described. The following embodiments are exemplary and are only used to explain the present invention, and should not be understood as limiting the present invention.

[0049] The comparative preparation examples and preparation examples are used to illustrate the metal catalysts and their preparation methods used in the comparative examples and examples. Unless otherwise specified, the hydrogen-containing atmosphere is a mixture of H2 and N2, wherein the volume fraction of H2 is 5% and the volume fraction of N2 is 95%.

[0050] Preparation Example 1

[0051] At room temperature, 5.8 g of Ni(NO₃)₂·6H₂O, 7.5 g of Al(NO₃)₃·9H₂O, and 0.74 g of LaCl₃·7H₂O were ultrasonically dissolved in 50 mL of deionized water to obtain a metal salt solution. Subsequently, 50 mL of a 1.2 mol / L aqueous Na₂CO₃ solution was slowly added dropwise to the metal salt solution under magnetic stirring for 20 minutes. After the addition, the mixture was stirred at room temperature for 3 hours, forming a mixture containing a precipitate. The mixture was then placed in a water bath, heated to 60°C, and aged for 12 hours. The aged product was filtered, and the resulting filter cake was washed with deionized water several times with stirring until the final wash was neutral, then dried at 120°C for 8 hours. The dried product was ground and passed through a 100-mesh sieve. The sieve residue was then heated to 500°C in a muffle furnace at 5°C / min and calcined for 4 hours to obtain a calcined product. Finally, the calcined product was placed in a tube furnace, and under the protection of a hydrogen atmosphere, the temperature was increased to 500°C at 5°C / min and reduced for 5h to obtain NiAlLa, which was recorded as NiAlLa (10:10:1).

[0052] Preparation Example 2

[0053] Catalyst NiAlLa was prepared according to the method of Preparation Example 1, except that the amount of Al(NO3)3·9H2O was adjusted to 3.75 g. The prepared catalyst was recorded as NiAlLa (10:5:1).

[0054] Preparation Example 3

[0055] Catalyst NiAlLa was prepared according to the method of Preparation Example 1, except that the amount of LaCl3·7H2O was adjusted to 1.48 g. The prepared catalyst was recorded as NiAlLa (10:10:2).

[0056] Preparation Example 4

[0057] Catalyst NiAlLa was prepared according to the method of Preparation Example 1, except that the reduction temperature was adjusted to 400°C. The prepared catalyst was recorded as NiAlLa-400.

[0058] Preparation Example 5

[0059] Catalyst NiAlLa was prepared according to the method of Preparation Example 1, except that the reduction temperature was adjusted to 600°C. The prepared catalyst was recorded as NiAlLa-600.

[0060] Preparation Examples 6 to 9

[0061] NiAlLa was prepared according to the method of Preparation Example 1, except that the amounts of Ni(NO₃)₂·6H₂O and Al(NO₃)₃·9H₂O were adjusted to produce NiAlLa with different metal molar ratios. The specific amounts of the aforementioned metal salts and the prepared catalysts are shown in Table 1.

[0062] Table 1

[0063] Serial number Nickel salt dosage / g Aluminum salt dosage / g Catalyst No. Preparation Example 6 6.96 6.0 NiAlLa (12:8:1) Preparation Example 7 4.64 9.0 NiAlLa (8:12:1) Preparation Example 8 5.8 6.0 NiAlLa (10:8:1) Preparation Example 9 4.64 7.5 NiAlLa (8:10:1)

[0064] Note: In the catalyst number, the numerical ratio in brackets represents the molar ratio of the three metals.

[0065] Comparative Preparation Example 1

[0066] At room temperature, 5.8 g of Ni(NO₃)₂·6H₂O was ultrasonically dissolved in 50 mL of deionized water to obtain a salt solution. Subsequently, 50 mL of a 1.2 mol / L aqueous Na₂CO₃ solution was slowly added dropwise to the salt solution under magnetic stirring for 20 minutes. After the addition, stirring continued at room temperature for 3 hours, forming a mixture containing a precipitate. The mixture was then placed in a water bath, heated to 60°C, and aged for 12 hours. The aged product was filtered, and the resulting filter cake was washed with deionized water several times with stirring until the final wash was neutral, then dried at 120°C for 8 hours. The dried product was ground and passed through a 100-mesh sieve. The sieve residue was placed in a muffle furnace and heated to 500°C at 5°C / min and calcined for 4 hours to obtain the calcined product (nickel oxide). Finally, the calcined product was reduced in a tube furnace under the protection of a mixed gas at 5°C / min to 500°C for 5 hours to obtain the nickel catalyst, designated NiOx.

[0067] Comparative Preparation Example 2

[0068] At room temperature, 7.5 g of Al(NO₃)₃·9H₂O and 0.74 g of LaCl₃·7H₂O were ultrasonically dissolved in 50 mL of deionized water to obtain a salt solution. Subsequently, 50 mL of a 1.2 mol / L aqueous Na₂CO₃ solution was slowly added dropwise to the salt solution under magnetic stirring for 20 minutes. After the addition, the mixture was stirred at room temperature for 3 hours, forming a mixture containing a precipitate. The mixture was then placed in a water bath, heated to 60°C, and aged for 12 hours. The aged product was filtered, and the resulting filter cake was washed with deionized water under stirring until the final wash was neutral, then dried at 120°C for 8 hours. The dried product was ground and passed through a 100-mesh sieve. The sieve residue was then placed in a muffle furnace and heated to 500°C at 5°C / min and calcined for 4 hours to obtain the calcined product (aluminum lanthanum oxide). Finally, the calcined product was placed in a tube furnace, and under the protection of the mixed gas, the temperature was raised to 500°C at 5°C / min and reduced for 5h to obtain an aluminum-lanthanum binary catalyst, which was recorded as AlLa (10:1).

[0069] Comparative Preparation Example 3

[0070] At room temperature, 5.8 g of Ni(NO₃)₂·6H₂O and 7.5 g of Al(NO₃)₃·9H₂O (0.02 mol) were ultrasonically dissolved in 50 mL of deionized water to obtain a salt solution. Subsequently, 50 mL of a 1.2 mol / L aqueous Na₂CO₃ solution was slowly added dropwise to the salt solution under magnetic stirring for 20 minutes. After the addition, the mixture was stirred at room temperature for 3 hours, forming a mixture containing a precipitate. The mixture was then placed in a water bath, heated to 60°C, and aged for 12 hours. The aged product was filtered, and the resulting filter cake was washed with deionized water under stirring until the final wash was neutral, then dried at 120°C for 8 hours. The dried product was ground and passed through a 100-mesh sieve. The sieve residue was then heated to 500°C in a muffle furnace at 5°C / min and calcined for 4 hours to obtain a calcined product. Finally, the calcined product was placed in a tube furnace, and under the protection of the mixed gas, the temperature was increased to 500°C at 5°C / min and reduced for 5h to obtain a nickel-aluminum binary catalyst, which was recorded as NiAl (10:10).

[0071] Comparative Preparation Example 4

[0072] At room temperature, 5.8 g of Ni(NO₃)₂·6H₂O and 0.74 g of LaCl₃·7H₂O were ultrasonically dissolved in 50 mL of deionized water to obtain a salt solution. Subsequently, 50 mL of a 1.2 mol / L aqueous Na₂CO₃ solution was slowly added dropwise to the salt solution under magnetic stirring for 20 minutes. After the addition, the mixture was stirred at room temperature for 3 hours to form a mixture containing a precipitate. The mixture was then placed in a water bath, heated to 60°C, and aged for 12 hours. The aged product was filtered, and the resulting filter cake was washed with deionized water under stirring until the final wash was neutral, then dried at 120°C for 8 hours. The dried product was ground and passed through a 100-mesh sieve. The sieve residue was then heated to 500°C in a muffle furnace at 5°C / min and calcined for 4 hours to obtain a calcined product. Finally, the calcined product was placed in a tube furnace, and under the protection of the mixed gas, the temperature was raised to 500°C at 5°C / min and reduced for 5h to obtain a nickel-lanthanum binary catalyst, which was recorded as NiLa (10:1).

[0073] Comparative Preparation Example 5

[0074] Catalyst NiAlLa was prepared according to the method of Preparation Example 1, except that no reduction treatment was performed. The prepared catalyst was recorded as NiAlLa-C.

[0075] Comparative Preparation Example 6

[0076] Catalyst NiAlLa was prepared according to the method of Preparation Example 1, except that the amount of Ni(NO3)2·6H2O was adjusted to 2.9 g. The prepared catalyst was recorded as NiAlLa (5:10:1).

[0077] Comparative Preparation Examples 7-8

[0078] The ternary catalyst was prepared according to the method of Preparation Example 1, except that Ni(NO3)2·6H2O was replaced by 5.82g Co(NO3)2·6H2O and 4.82g Cu(NO3)2·3H2O, respectively. The prepared catalysts were recorded as CoAlLa (10:10:1) and CuAlLa (10:10:1), respectively.

[0079] Comparative Preparation Examples 9-10

[0080] The ternary catalyst was prepared by referring to the method of Preparation Example 1, except that Al(NO3)3·9H2O was replaced by 5.12g Mg(NO3)2·6H2O and 8.58g Zr(NO3)4·5H2O, respectively. The prepared catalysts were recorded as NiMgLa (10:10:1) and NiZrLa (10:10:1), respectively.

[0081] Comparative Preparation Examples 11-12

[0082] The ternary catalyst was prepared by referring to the method of Preparation Example 1, except that LaCl3·7H2O was replaced by 0.86gCe(NO3)3·6H2O and 0.52g SnCl4, respectively. The prepared catalysts were recorded as NiAlCe (10:10:1) and NiAlSn (10:10:1), respectively.

[0083] The following examples illustrate methods for hydrogenating 5-hydroxymethylfurfural using the metal catalysts described in the above-described Preparation Examples and Comparative Preparation Examples. The product analysis and quantification methods are as follows: The supernatant was filtered through a 0.22 μm filter membrane and analyzed using a gas chromatograph (Shimadzu, model GC-2014C, equipped with a DB-WAXETR capillary column (30.0 m × 0.32 mm × 0.25 μm) and a flame ion detector (FID)). The product's qualitative properties were compared with a standard sample. The test conditions are shown in Table 2.

[0084] Table 2

[0085] project condition Detector: FID (280℃) Initial column temperature: 40℃ Inlet temperature: 250℃ Final column temperature: 250℃ Injection volume: 1 μL Analytical methods: External standard method

[0086] Test heating program: adopt the initial column temperature of 40℃ and maintain it for 2 minutes, then increase the temperature to 100℃ at 5℃ / min and maintain it for 2 minutes, and finally increase the temperature to the final column temperature of 250℃ at 10℃ / min and maintain it for 4 minutes. Prepare standard solutions of HMF, BHMF and BHMTHF, draw standard curves of concentration and response peak area, and use the standard curves to determine the concentration of each main component in the liquid, and calculate the substrate conversion rate and product yield according to the formula. The substrate conversion rate, product yield (yield) and selectivity of the target product are calculated by the following formula:

[0087]

[0088] Wherein, the reaction molar amount of HMF = the initial molar amount of HMF - the molar amount of HMF in the product

[0089] Example 1

[0090] A stainless steel autoclave was charged with 0.1 g of 5-hydroxymethylfurfural, 0.1 g of the catalyst NiAlLa (10:10:1), and 20 mL of sec-butanol. The autoclave was sealed and nitrogen was introduced to displace the air in the autoclave. Hydrogen was then introduced at 3 MPa at room temperature and stirred at 500 rpm. The hydrogenation reaction was carried out by heating to 120°C and maintaining the temperature for 1.5 hours. After the reaction was completed, the mixture was naturally cooled to room temperature and the resulting product was centrifuged to obtain a supernatant containing the reaction product. The composition of the supernatant was analyzed by gas chromatography, and the test results are shown in Table 3.

[0091] Figure 2 The gas chromatogram of the product liquid (i.e., supernatant) of this embodiment is shown in FIG. The gas phase analysis results of the standard sample show that BHMF peaks at around retention time 29.5 min, HMF peaks at around retention time 28.9 min, and BHMTHF peaks at around retention time 26.4 min. Figure 2 It can be seen that only two obvious peaks appear in the gas chromatogram, corresponding to the solvent sec-butanol and the product BHMTHF, respectively. This shows that after the reaction of HMF, the supernatant basically does not contain the substrate, and no other by-products are produced. The main product is BHMTHF.

[0092] Examples 2-3

[0093] Catalytic hydrogenation of 5-hydroxymethylfurfural was carried out according to the method of Example 1, except that the catalyst NiAlLa (10:10:1) was replaced with NiAlLa (10:10:2) and NiAlLa-600, respectively. The composition of the resulting supernatant was analyzed by gas chromatography, and the test results are shown in Table 3.

[0094] Comparative Examples 1 to 12

[0095] Catalytic hydrogenation of 5-hydroxymethylfurfural was carried out according to the method of Example 1, except that the NiAlLa (10:10:1) catalyst was replaced with the catalysts of Comparative Preparation Examples 1 to 12, respectively, as shown in Table 3. The composition of the resulting supernatant was analyzed by gas chromatography, and the test results are shown in Table 3.

[0096] Table 3

[0097]

[0098]

[0099] Note: The conversion rate of "99.99%" means that the characteristic chromatographic peak of HMF was almost not detected in the supernatant analyzed by gas chromatography, indicating that HMF in the reaction system was completely converted.

[0100] In conjunction with Table 1, by comparing Example 1 with Comparative Examples 1 to 4, it can be seen that under the same hydrogenation reaction conditions, the conversion rate of HMF and the yield of BHMTHF catalyzed by NiAlLa (10:10:1) in Example 1 are both close to 100%, and the BHMTHF selectivity is 99.17%, which are significantly higher than the corresponding effects of Comparative Examples 1 to 4. This shows that Ni (active center), Al (acidic carrier promotes hydrogenation), and La (stabilizing structure / modulating electrons) work together to significantly improve the efficiency of target product formation. Specifically, in Comparative Example 1, the nickel catalyst used to catalyze HMF had a conversion rate of only 34.43% and a BHMTHF yield of 2.04%, indicating that the catalytic activity of a single metal Ni as the active component was insufficient; in Comparative Example 2, the bimetallic AlLa catalyst used to catalyze HMF had a conversion rate of only 31.19%, and no BHMTHF was produced, indicating that Ni is the core of the hydrogenation reaction, while Al and La lack hydrogenation activity; in Comparative Example 3, the bimetallic NiAl catalyst used to catalyze HMF had a higher conversion rate, but the BHMTHF yield was only 50.36%, indicating that although the Al support promotes Ni dispersion, the hydrogenation pathway is not fully activated in the absence of La; in Comparative Example 4, the bimetallic NiLa catalyst used to catalyze HMF had a conversion rate of 56.49% and a BHMTHF yield of only 9.77%, indicating that although La can regulate Ni activity, the metal dispersion is poor in the absence of Al, and the active sites are insufficient.

[0101] Comparing Example 1 with Comparative Example 12, it can be seen that when the nickel content in the three-way catalyst is too low, the catalytic activity will also decrease, affecting the efficiency of the hydrogenation reaction.

[0102] Comparing Examples 1 and 3 with Comparative Example 5, it can be seen that in Examples 1 and 3, the catalysts prepared by high-temperature reduction can promote the interaction between Ni-Al-La, and the Ni metal obtains a better reduction effect, forming a more stable active structure, and significantly improving the hydrogenation ability. The catalyst of Comparative Example 5 was not reduced, and the conversion rate was only 40.74%, and no BHMTHF was generated, indicating that the metal needs to be reduced to a single state (Ni 0 ) has hydrogenation activity.

[0103] Comparing Example 1 with Comparative Examples 6 to 11, it can be seen that when Ni is replaced by Co and Cu, CoAlLa maintains a relatively high reactant conversion rate, the yield of BHMF is much greater than that of BHMTHF, indicating that Co is more inclined to generate BHMF and the hydrogenation path is inhibited. The conversion rate of HMF catalyzed by CuAlLa decreases significantly, the yields of the two hydrogenation products are not high, and the catalytic activity is obviously insufficient. In addition, when Al is replaced by Mg and Zr, although NiMgLa also has a relatively high HMF conversion rate, the yield of the hydrogenation product is not high. It can be seen that the introduction of magnesium promotes the partial hydrogenation reaction, but its hydrogenation selectivity is lower than that of NiAlLa; the catalytic HMF conversion rate of NiZrLa is not low, but its hydrogenation selectivity is not high either. The reason for this may be that the acidity of zirconium inhibits the formation of the target product. Finally, when La was replaced by Ce and Sn, the HMF conversion rate of NiAlCe was 87.43%, but the BHMF yield was much higher than that of BHMTHF, indicating that the oxygen storage capacity of cerium may affect the hydrogenation path; the HMF conversion rate of NiAlSn was higher, but the BHMF yield was much higher than that of BHMTHF, indicating that the introduction of tin significantly favored the formation of BHMF and weakened the hydrogenation ability.

[0104] In summary, in the NiAlLa trimetallic combination, the hydrogenation activity of Ni, the support acidity of Al, and the synergistic effect of La jointly promote the efficient generation of BHMTHF, which shows the importance of the synergistic effect of the trimetallic combination.

[0105] Example 4

[0106] A stainless steel autoclave was charged with 0.1 g of 5-hydroxymethylfurfural, 0.1 g of the catalyst NiAlLa (10:5:1), and 20 mL of sec-butanol. The autoclave was sealed, and nitrogen was introduced to displace the air in the autoclave. Hydrogen was then introduced at 3 MPa at room temperature, and stirring was initiated at 500 rpm. The mixture was heated to 120°C and maintained for 3 hours to carry out the hydrogenation reaction. After the reaction was completed, the mixture was naturally cooled to room temperature, and the resulting product was centrifuged to obtain a supernatant containing the reaction product. The composition of the supernatant was analyzed by gas chromatography, and the test results are shown in Table 4.

[0107] Example 5

[0108] The catalytic hydrogenation reaction of 5-hydroxymethylfurfural was carried out according to the method of Example 4, except that the catalyst (10:5:1) was replaced with NiAlLa-400. The composition of the obtained supernatant was analyzed by gas chromatography, and the test results are shown in Table 4.

[0109] Example 6

[0110] A stainless steel autoclave was charged with 0.1 g of 5-hydroxymethylfurfural, 0.1 g of the catalyst NiAlLa (12:8:1), and 20 mL of sec-butanol. The autoclave was sealed, and nitrogen was introduced to displace the air in the autoclave. Hydrogen was then introduced at 3 MPa at room temperature, and stirring was initiated at 500 rpm. The mixture was heated to 120°C and maintained for 2 hours to carry out the hydrogenation reaction. After the reaction was completed, the mixture was naturally cooled to room temperature, and the resulting product was centrifuged to obtain a supernatant containing the reaction product. The composition of the supernatant was analyzed by gas chromatography, and the test results are shown in Table 4.

[0111] Example 7

[0112] A stainless steel autoclave was charged with 0.1 g of 5-hydroxymethylfurfural, 0.1 g of the catalyst NiAlLa (8:12:1), and 20 mL of sec-butanol. The autoclave was sealed, and nitrogen was introduced to displace the air in the autoclave. Hydrogen was then introduced at 3 MPa at room temperature, and stirring was initiated at 500 rpm. The mixture was heated to 120°C and maintained for 2.5 hours to carry out the hydrogenation reaction. After the reaction was completed, the mixture was naturally cooled to room temperature, and the resulting product was centrifuged to obtain a supernatant containing the reaction product. The composition of the supernatant was analyzed by gas chromatography, and the test results are shown in Table 4.

[0113] Example 8

[0114] A stainless steel autoclave was charged with 0.1 g of 5-hydroxymethylfurfural, 0.1 g of the catalyst NiAlLa (10:8:1), and 20 mL of sec-butanol. The autoclave was sealed, and nitrogen was introduced to displace the air in the autoclave. Hydrogen was then introduced at 3 MPa at room temperature, and stirring was initiated at 500 rpm. The autoclave was heated to 120°C and maintained for 2 hours to carry out the hydrogenation reaction. After the reaction was completed, the reaction was naturally cooled to room temperature, and the resulting product was centrifuged to obtain a supernatant containing the reaction product. The composition of the supernatant was analyzed by gas chromatography, and the test results are shown in Table 4.

[0115] Example 9

[0116] A stainless steel autoclave was charged with 0.1 g of 5-hydroxymethylfurfural, 0.1 g of the catalyst NiAlLa (8:10:1), and 20 mL of sec-butanol. The autoclave was sealed, and nitrogen was introduced to displace the air in the autoclave. Hydrogen was then introduced at 3 MPa at room temperature, and stirring was initiated at 500 rpm. The mixture was heated to 120°C and maintained for 2.5 hours to carry out the hydrogenation reaction. After the reaction was completed, the mixture was naturally cooled to room temperature, and the resulting product was centrifuged to obtain a supernatant containing the reaction product. The composition of the supernatant was analyzed by gas chromatography, and the test results are shown in Table 4.

[0117] Table 4

[0118]

[0119] Combining Tables 3 and 4, it can be seen that controlling the molar ratio of NiAlLa to (8-12):(5-12):(1-2) not only improves the conversion of HMF, but also improves the selectivity and yield of the target product BHMTHF. Furthermore, comparing Examples 1, 3, and 5 shows that, when BHMTHF yields are comparable, hydrogenation using a catalyst with a reduction temperature greater than 400°C can effectively shorten the hydrogenation reaction time and efficiently produce the target product.

[0120] Examples 10 to 12

[0121] The catalytic hydrogenation reaction of 5-hydroxymethylfurfural was carried out according to the method of Example 1, except that the reaction temperature was adjusted to 110° C., 130° C., and 140° C. The composition of the obtained supernatant was analyzed by gas chromatography, and the test results are shown in Table 5.

[0122] Table 5

[0123]

[0124] As shown in Table 5, when the reaction temperature is controlled between 110 and 140°C, the hydrogenation reaction can achieve almost complete conversion of HMF within 1.5 h. When the reaction temperature is increased from 110°C to above 120°C, BHMF can be further hydrogenated to BHMTHF, and the yield thereof increases from 80.46% to over 95%. This indicates that the mild reaction conditions of 110 to 140°C are conducive to maintaining a high BHMTHF yield, and BHMTHF will not undergo further side reactions such as etherification and ring opening.

[0125] Examples 13 to 18

[0126] The catalytic hydrogenation reaction of 5-hydroxymethylfurfural was carried out according to the method of Example 1, except that the reaction time was adjusted as shown in Table 6. The composition of the obtained supernatant was analyzed by gas chromatography, and the test results are shown in Table 6.

[0127] Table 6

[0128]

[0129] As shown in Table 6, high conversion rates and target product selectivity can be achieved within 1 to 5 h of reaction time, and the yield of BHMTHF is maintained above 94%.

[0130] Examples 19-20

[0131] The catalytic hydrogenation reaction of 5-hydroxymethylfurfural was carried out according to the method of Example 1, except that the catalyst and hydrogenation reaction conditions were adjusted according to Table 7. The composition of the obtained supernatant was analyzed by gas chromatography, and the test results are shown in Table 7.

[0132] Table 7

[0133]

[0134]

[0135] Examples 21 to 24

[0136] The catalytic hydrogenation reaction of 5-hydroxymethylfurfural was carried out according to the method of Example 1, except that the amount of catalyst was adjusted as shown in Table 8. The composition of the obtained supernatant was analyzed by gas chromatography, and the test results are shown in Table 8.

[0137] Table 8

[0138]

[0139] As shown in Table 8, when the mass ratio of catalyst to reactant is controlled at (0.75-1.5):1, a higher conversion rate and target product yield can be obtained. Excessive use of catalyst does not lead to a continuous increase in by-products in the reaction system due to the provision of more catalytic active sites.

[0140] Examples 25 to 28 and Comparative Example 13

[0141] The catalytic hydrogenation reaction of 5-hydroxymethylfurfural was carried out according to the method of Example 1, except that the hydrogen pressure was adjusted as shown in Table 9. The composition of the obtained supernatant was analyzed by gas chromatography, and the test results are shown in Table 9.

[0142] Table 9

[0143]

[0144] Table 9 shows that when no hydrogen was added, the HMF conversion was 75.10%, the HMF yield was 62.42%, and the BHMF yield was 5.32%. This indicates that the catalyst is able to activate sec-butanol to release hydrogen ions when using it as the solvent. Therefore, sec-butanol serves as both a solvent and a hydrogen donor in the reaction. After hydrogen addition, BHMF is primarily produced at low hydrogen pressures. As pressure increases, the reaction pathway shifts to the production of BHMTHF, which is further hydrogenated and converted. The BHMTHF yield and selectivity are optimal at 3 MPa. Higher pressures have a more gradual effect on the product, resulting in only a slight decrease in the BHMTHF yield.

[0145] Examples 29 to 33

[0146] The catalytic hydrogenation reaction of 5-hydroxymethylfurfural was carried out according to the method of Example 1, except that the solvent type was adjusted as shown in Table 10. The composition of the obtained supernatant was analyzed by gas chromatography, and the test results are shown in Table 10.

[0147] Table 10

[0148]

[0149] As shown in Table 10, BHMTHF can be effectively synthesized using low-carbon alcohols, and compared to other low-carbon alcohols adopted, sec-butanol can significantly improve the productive rate and yield of BHMTHF. The reason for this may be that, in the hydrogenation reaction, sec-butanol reduction potential is the lowest, and lower reduction potential means that sec-butanol is more easily reduced in the hydrogenation reaction, and does not require the reaction conditions such as too high temperature and pressure to react smoothly. In addition, compared to other low-carbon alcohols, sec-butanol can realize hydrogenation conversion under relatively mild conditions, which not only reduces the requirements for reaction equipment, but also reduces energy consumption and production cost, and in complex multi-pathway reaction systems, sec-butanol is more inclined to react according to the expected hydrogenation path to generate target product, and is not prone to side reaction to generate other impurities, which is conducive to improving the purity and quality of the product, reducing the step of subsequent separation and purification, and further reducing production cost.

[0150] Test Case

[0151] XRD analysis of the catalyst was performed. XRD patterns were obtained using a MiniFlex 600 X-ray diffractometer from Rigaku, Japan. The energy mode was set to standard, with a Cu-Kα source at a voltage of 40 kV and a current of 30 mA. The step size was set to 0.02, the scanning range was 10–80° (2θ), and the scanning speed was 10° / min.

[0152] The XRD test results of the metal catalysts prepared in Preparation Examples 1 to 5 and Comparative Preparation Examples 3 to 6 are as follows: Figure 1 As shown. Figure 1As shown in the figure, the ternary catalysts with different Ni / Al / La ratios all show characteristic peaks in the XRD patterns. Among them, the diffraction peaks at 44.5°, 51.8° and 76.4° correspond to the (111), (200) and (220) crystal planes of Ni (PDF#04-004-3634), respectively, and the diffraction peaks at 37.2°, 43.2° and 62.8° correspond to the (111), (200) and (220) crystal planes of NiO (PDF#97-006-1318), respectively. In addition, a single broad diffuse scattering peak of Al2O3 appears at 20.4°, without a sharp crystalline diffraction peak. This indicates that the Al2O3 formed by the catalyst is amorphous. Amorphous Al2O3 generally has a higher specific surface area and a higher content of surface hydroxyl groups, and can be regarded as a catalyst support, which is conducive to surface reactions. Moreover, compared with the catalyst NiAlLa (10:10:1), other bimetallic catalysts NiLa (10:1), NiAl (10:10), and NiAlLa (10:5:1) all showed corresponding NiO characteristic peaks, indicating that a small amount of Ni element in these catalysts still exists in the form of NiO. Under the reduction conditions of 500°C, the prepared NiAlLa (10:10:1) has the best reduction effect and its catalytic effect in preparing BHMTHF from HMF is also the best.

[0153] It is worth noting that when the molar ratio of the three in the catalyst NiAlLa is kept unchanged at 10:10:1, no reduction is adopted or the reduction temperature is lowered to 400°C (NiAlLa-C, NiAlLa-400), the catalyst does not show obvious diffraction peaks. However, when the reduction temperature of the catalyst NiAlLa (10:10:1) is increased to 600°C (Preparation Example 5), the catalyst shows an Al2O3 crystal diffraction peak at 20.4°. This phenomenon shows that the catalyst reduction temperature has an important influence on crystal formation. The Ni grains synthesized at a lower reduction temperature are fine and the strength is reduced. A higher reduction temperature will promote Al2O3 crystallization. The catalyst prepared at a reduction temperature of 500°C (Preparation Example 1) has a significant Ni characteristic peak and no NiO characteristic peak, which verifies the high efficiency of the NiAlLa trimetallic catalyst.

[0154] Finally, it should be noted that the above preparation examples are only used to illustrate the technical solutions of the present invention, rather than to limit them. Although the present invention has been described in detail with reference to the above preparation examples, those skilled in the art should understand that the technical solutions described in the above preparation examples can still be modified, or some or all of the technical features therein can be replaced by equivalents. These modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the preparation examples of the present invention, and they should all be included in the scope of the claims and description of the present invention. In particular, as long as there is no structural conflict, the various technical features mentioned in the preparation examples can be combined in any way. The present invention is not limited to the specific preparation examples disclosed herein, but includes all technical solutions that fall within the scope of the claims.

Claims

1. A method for preparing 2,5-dihydroxymethyltetrahydrofuran from 5-hydroxymethylfurfural, characterized in that: The method comprises: in the presence of a metal catalyst and an alcohol solvent, contacting 5-hydroxymethylfurfural with hydrogen to carry out a hydrogenation reaction to form a reaction product containing 2,5-dihydroxymethyltetrahydrofuran and optionally 2,5-furan dimethanol; wherein the metal catalyst is a nickel-aluminum-lanthanum ternary catalyst, and the molar ratio of Ni, Al and La in the nickel-aluminum-lanthanum ternary catalyst is (8-12):(5-12):(1-2).

2. The method according to claim 1, characterized in that In the nickel-aluminum-lanthanum ternary catalyst, based on the total amount of Ni, Al and La, the molar content of Ni is 40% to 60%, the molar content of Al is 32% to 52%, and the molar content of La is 4% to 8%.

3. The method according to claim 1 or 2, characterized in that The metal catalyst is prepared by a method comprising the following steps: 1) subjecting metal salts including nickel salts, aluminum salts and lanthanum salts to a precipitation reaction with a precipitant in water and aging the reaction to obtain a solid-liquid product; 2) performing solid-liquid separation on the solid-liquid product, and washing, drying and calcining the obtained solid; 3) reducing the calcined product obtained in step 2) in a hydrogen-containing atmosphere to obtain a metal catalyst; Preferably, the molar ratio of the total amount of the metal salt to the amount of the precipitant is 1:(1.5-5); Preferably, the nickel salt is nickel nitrate, the aluminum salt is aluminum nitrate, and the lanthanum salt is lanthanum chloride and / or lanthanum nitrate; Preferably, the precipitant is sodium carbonate.

4. The method according to claim 3, characterized in that Step 1) The following processes are included: 1-1) adding dropwise a precipitant aqueous solution to a metal salt aqueous solution containing a nickel salt, an aluminum salt, and a lanthanum salt to perform a precipitation reaction; 1-2) aging the product obtained in step 1-1) to obtain a solid-liquid product; Preferably, the volume ratio of the metal salt aqueous solution to the precipitant aqueous solution is (0.8-1.2):

1.

5. The method according to claim 3, characterized in that The conditions of the precipitation reaction include: temperature of 15 to 40° C. and time of 2 to 6 hours; Preferably, the aging conditions include: a temperature of 50 to 80° C. and a time of 8 to 15 hours.

6. The method according to claim 3, characterized in that The drying temperature is 90-130°C and the drying time is 3-10 hours; Preferably, the calcination is carried out in an oxygen-containing atmosphere, and the calcination conditions include: a temperature of 350 to 600° C. and a time of 3 to 8 hours.

7. The method according to claim 3, characterized in that The hydrogen-containing atmosphere is a mixture of hydrogen and nitrogen, and the volume content of hydrogen in the mixture is 2% to 8%; Preferably, the reduction temperature is 400-600°C, more preferably 500-600°C.

8. The method according to any one of claims 1 to 7, characterized in that The mass ratio of the metal catalyst to 5-hydroxymethyl furfur is (0.25-1.5):1, preferably (0.5-1):1; The conditions of the hydrogenation reaction include: temperature of 90 to 140° C. and time of 1 to 5 hours; Preferably, the hydrogenation reaction is carried out in a high-pressure reactor under stirring conditions at a stirring speed of 300 to 700 rpm.

9. The method according to any one of claims 1 to 8, characterized in that The alcohol solvent is selected from at least one of methanol, ethanol, n-propanol, isopropanol, n-butanol and sec-butanol; Preferably, the alcohol solvent is sec-butanol; Preferably, the alcohol solvent is used in an amount such that the concentration of 5-hydroxymethylfurfural is 1 to 150 g / L.

10. The method according to any one of claims 1 to 9, characterized in that In the reaction product, the molar content of 2,5-dihydroxymethyltetrahydrofuran is greater than 80%; Preferably, the method further comprises: centrifuging the reaction system after the hydrogenation reaction to recover the metal catalyst therein.

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