Modified MOFs carrier, supported catalyst, and preparation method and application thereof

Abstract

The present invention discloses a modified MOFs carrier, a supported catalyst, and a preparation method and application thereof. The preparation method of the modified MOFs carrier comprises: subjecting a mixed reaction system comprising a carboxylate ligand, a zirconium salt, a stabilizer, a modifier, and a first organic solvent to a dynamic crystallization reaction to obtain a modified MOFs precursor, followed by a vacuum activation treatment to obtain a modified MOFs carrier. The present invention also discloses a preparation method of a supported catalyst, comprising: supporting a metal element on the modified MOFs carrier, followed by a roasting treatment and a reduction treatment to obtain a supported catalyst. The present invention prepares a supported catalyst process using modified MOFs as a carrier, which is simple, safe, and reliable. At the same time, when the metal supported catalyst is used to prepare 2,5-furan dimethanol, it has strong controllability, strong reaction activity, high selectivity, good reusability, good reproducibility, and is safe and pollution-free.

Description

Technical Field

[0001] The present invention belongs to the field of chemical technology and relates to a modified MOFs carrier and a preparation method thereof, in particular to a supported catalyst using the modified MOFs as a carrier and a preparation method thereof, and use thereof in preparing 2,5-furan dimethanol. Background Art

[0002] With the rapid development of the global economy, the contradiction between the dwindling traditional oil resources and the ever-increasing demand for fossil fuels is becoming increasingly prominent. A viable development strategy is to efficiently convert excess or waste biomass into high-value-added, functionally enhanced fine chemicals. This approach, gradually promoting the large-scale transition from decentralized raw material processing to centralized processing, will ultimately achieve performance compensation for conventional petroleum-based chemicals.

[0003] Leveraging the petrochemical industry's basic molding equipment, innovative and efficient catalytic processes can directly transform biomass resources into platform compounds that are difficult to produce via petrochemical routes. This not only fully utilizes the molecular structural characteristics of biomass, but also has the potential to enhance the gas barrier, heat resistance, and biodegradability of petroleum-based products. Currently, there are more than ten widely recognized bio-based platform compounds, among which 5-hydroxymethylfurfural, which possesses both disubstituted (polymerizable) and aromatic (structural rigidity) structural characteristics, is considered a bridge compound connecting bio-based sugar chemistry and petroleum-based chemistry. The European Union lists 5-hydroxymethylfurfural (HMF) and 2,5-furandicarboxylic acid (FDCA) as the most important six-carbon platform compounds in its "Medium- and Long-Term Challenges for the Production of Commodity Chemicals from Renewable Raw Materials Using Biotechnology 2006-2050." Meanwhile, the U.S. Department of Energy lists HMF as one of the top ten bio-based platform compounds. The HMF molecule contains furan rings, hydroxyl groups and aldehyde groups. Through chemical reactions such as hydrogenation, oxidation, esterification, halogenation and polymerization, it can be used to produce popular chemicals such as polymer monomers, liquid fuels, and green solvents, and can also be converted into fine chemicals such as drugs and dye intermediates.

[0004] MOFs (Metal-Organic Frameworks) materials, also known as porous coordination polymers, are porous crystalline materials with two-dimensional or three-dimensional infinite structures formed by metal ions or clusters coordinated to multidentate organic ligands. MOFs materials are mainly divided into four categories: network structure, Lavoisier structure, UIO material, and zeolite imidazolate framework structure materials. Compared with traditional inorganic materials, MOFs have novel structures and highly ordered structures. They can be designed and grafted. Due to their pore structure, MOFs materials have a large specific surface area and porosity, making this type of material very suitable for stabilizing metal nanoparticles for heterogeneous catalytic reactions. In addition, MOFs materials are used as templates or precursors to construct nanoporous carbon materials or oxides, so that MOFs-derived materials have the advantages of high specific surface area and porous characteristics as well as uniform doping of heteroatoms.

[0005] MOF-based catalysts have also been widely used in the field of biomass conversion. MOFs, with their unique structural and physicochemical properties, significantly outperform conventional porous materials in biomass conversion. For example, the metal nodes and organic ligands of MOFs can be used directly or, during post-processing, groups can be introduced as acidic or basic centers (-SO3H, -NH2) or redox centers (Cr, Cu, Ti, Fe, Co, etc.), promoting reaction conversion and selectivity. The porosity of MOFs can be fine-tuned by rationally selecting organic linkers or adjusting synthesis parameters, thereby facilitating the diffusion of biomass-derived molecules and facilitating their access to active centers deposited in the catalyst matrix. Furthermore, MOFs can serve as supports to uniformly immobilize or encapsulate a large number of active species (metal and metal oxide nanoparticles, polyoxometalates, quantum dots, organometallic molecules, etc.), preventing their leaching, aggregation, or deactivation during the reaction. Finally, MOFs can be used as sacrificial templates or precursors to synthesize metal-carbon composites for specialized catalytic applications requiring high thermal stability, high graphitization, or metal-carbon synergy. These characteristics endow MOF-based materials with suitable and tunable physicochemical properties, making them suitable for a variety of biomass catalytic reactions, including dehydration, hydrolysis, isomerization, condensation, rearrangement, hydrogenation, oxidation, esterification, polymerization, and hydrodeoxygenation. Fan et al. prepared a porous carbon catalyst, CuCo / Zn, using uniform multimetallic doping and a self-templating method. They used it as a highly efficient non-precious metal catalyst for the hydrogenation of furfural to furfuryl alcohol. The selectivity for furfuryl alcohol reached 99.1%, and the conversion of furfural reached 95.8%. Analysis showed that the high activity of the CuCo / Zn catalyst is primarily due to the high dispersion of the metal nanoparticles, the pore structure formed by zinc overflow, and the synergistic effect between copper and cobalt.

[0006] At present, the most reported method is to use precious metals (Pt, Au, Pd) as catalysts to catalyze the transfer hydrogenation of 5-hydroxymethylfurfural to prepare 2,5-furan dimethanol. Although it has considerable yield and selectivity, its industrial development is restricted by the complex preparation process and high cost. Non-precious metals (Cu, Ni, Co) are used as catalysts to directly hydrogenate hydrogen to prepare 2,5-furan dimethanol. Although it has low cost and simple preparation process, it has low selectivity and low reaction substrate concentration. At the same time, the metal loaded on the catalyst is easy to fall off, the catalyst is easy to deactivate, difficult to regenerate, and has poor reuse rate, which has become a restriction on the research of its downstream derivative synthesis and limited its further industrial application. Summary of the Invention

[0007] The main purpose of the present invention is to provide a modified MOFs carrier, a supported catalyst using the modified MOFs as a carrier, and a preparation method thereof, so as to overcome the deficiencies in the prior art.

[0008] Another object of the present invention is to provide applications of the supported catalyst.

[0009] To achieve the aforementioned object of the invention, the technical solutions adopted by the present invention include:

[0010] An embodiment of the present invention provides a method for preparing a modified MOFs carrier, which includes: subjecting a mixed reaction system comprising a carboxylate ligand, a zirconium salt, a stabilizer, a modifier, and a first organic solvent to a dynamic crystallization reaction to obtain a modified MOFs precursor, followed by vacuum activation treatment to obtain a modified MOFs carrier.

[0011] The embodiments of the present invention also provide a modified MOFs carrier prepared by the aforementioned preparation method.

[0012] The present invention also provides a method for preparing a supported catalyst, which comprises:

[0013] The modified MOFs support was prepared according to the aforementioned method;

[0014] The metal elements are loaded on the modified MOFs carrier, and then calcined and reduced in sequence to obtain a loaded catalyst.

[0015] The embodiment of the present invention also provides a supported catalyst prepared by the above preparation method.

[0016] Furthermore, the supported catalyst includes: a modified MOFs carrier, and metal nanoparticles uniformly supported on the modified MOFs carrier.

[0017] The embodiment of the present invention also provides the use of the supported catalyst in the preparation of 2,5-furan dimethanol.

[0018] Accordingly, an embodiment of the present invention further provides a method for preparing 2,5-furan dimethanol, which comprises:

[0019] Under hydrogen atmosphere and selected pressure conditions, 5-hydroxymethylfurfural is catalyzed by the supported catalyst to undergo catalytic hydrogenation reaction to prepare 2,5-furan dimethanol.

[0020] Compared with the prior art, the beneficial effects of the present invention include at least:

[0021] 1) The special spatial geometric configuration formed by Zr-O and modified atoms in the modified MOFs carrier prepared by the present invention results in a large number of catalytic sites and porous structures distributed in its skeleton, which is beneficial to increasing the contact area between the reactants and the catalytic active sites, thereby promoting the reaction; secondly, it has a multi-level pore structure and a large window, with an extremely high specific surface area and a hierarchical porous structure, which can better stabilize metal nanoparticles and effectively help transport the reaction substrates in the catalytic reaction. It is used for heterogeneous catalytic reactions and has the advantages of both homogeneous catalysts and traditional heterogeneous catalysts.

[0022] 2) The surface of the modified MOFs carrier prepared by the present invention has been modified, and the modified atoms precisely fill the O vacancies in the special geometric spatial configuration formed by Zr-O to achieve regulation of the L acid sites in the carrier, enhancing the carrier's adsorption of HMF molecules during the hydrogenation reaction, allowing HMF molecules to contact the hydrogenation sites more frequently, better, and faster, achieving efficient conversion and hydrogenation. Furthermore, the L acid sites enhanced by the modified atoms are in close contact with the metal nanoparticles, shortening the physical distance between the two. The efficient synergistic effect of the metal and acid accelerates the diffusion rate between the active sites of the reactants, thereby improving the reaction rate and selectivity. Furthermore, due to the close relationship between the metal and the acid, the metal nanoparticles in the supported catalysts of the modified MOFs are less likely to fall off during multiple reactions under long-term high-temperature conditions, and their performance remains unchanged after high-temperature regeneration, effectively reducing costs.

[0023] 3) The process for preparing the supported catalyst of the present invention is simple, easy to operate, low in cost, simple to synthesize, safe and reliable. The supported metal nanoparticles are evenly dispersed due to the porosity and orderliness of the support, which can promote substrate transfer within the catalyst, thereby greatly improving the selectivity and yield of catalytic hydrogenation reduction to prepare 2,5-furan dimethanol.

[0024] 4) Compared with traditional supported catalysts, the catalyst prepared by the present invention has good reusability, is not easy to deactivate, has very high selectivity, strong specificity, and good regeneration. The catalyst can be washed and reused after the reaction, and the performance effect remains the same, which reduces the cost of use and has good application prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0026] Figure 1a and Figure 1b This is a scanning electron microscope (SEM) image of the modified MOFs support prepared in Example 1 of the present invention;

[0027] Figure 2 The scanning electron microscope (SEM) images of the modified MOFs support prepared under different conditions in Comparative Example 2;

[0028] Figure 3 The XPS valence state characterization diagram of the supported metal (Cu) of the supported catalysts with different loading amounts of modified MOFs as supports in Examples 14 and 22-24 of the present invention;

[0029] Figure 4 This is a transmission electron microscopy (TEM) image of the supported catalyst using modified MOFs as a carrier in Example 14 of the present invention;

[0030] Figure 5a-5d TEM particle size distribution analysis diagrams of supported catalysts with different loading amounts of modified MOFs as carriers in Example 22, Example 14, and Examples 23-24 of the present invention, respectively;

[0031] Figure 6 This is the XRD pattern of the supported catalyst using modified MOFs as a carrier in Example 22 of the present invention. DETAILED DESCRIPTION

[0032] In light of the aforementioned shortcomings of the prior art, the inventors of this case, after extensive research and extensive experimentation, have developed the technical solution of the present invention, which primarily provides a supported catalyst using modified MOFs as a support. This technical solution, its implementation process, and its principles are further explained below.

[0033] In the present invention, “HMF” is an abbreviation for 5-hydroxymethylfurfural, “BHMF” is an abbreviation for 2,5-furandimethanol, “DMF” is an abbreviation for N,N-dimethylformamide, and “PTA” is an abbreviation for terephthalic acid.

[0034] As one aspect of the technical solution of the present invention, a method for preparing a modified MOFs carrier involves: subjecting a mixed reaction system comprising a carboxylate ligand, a zirconium salt, a stabilizer, a modifier and a first organic solvent to a dynamic crystallization reaction to obtain a modified MOFs precursor, followed by vacuum activation treatment to obtain a modified MOFs carrier.

[0035] In some embodiments, the carboxylate ligand may specifically include any one of terephthalic acid, trimesic acid, naphthalene dicarboxylic acid, biphenyl-4,4-dicarboxylic acid, etc., but is not limited thereto.

[0036] In some embodiments, the zirconium salt includes an organic solvent-soluble zirconium salt. Specifically, the zirconium salt includes any one or a combination of two or more of zirconium chloride (zirconium chloride), zirconium nitrate, zirconium sulfate, etc., but is not limited thereto.

[0037] In some embodiments, the molar ratio of zirconium ions contained in the zirconium salt to terephthalic acid (ie, the concentration ratio in the mixed reaction system) is 1:0.1 to 1:5.

[0038] In some embodiments, the concentration of zirconium ions contained in the zirconium salt in the mixed reaction system is 0.1 to 100 mmol / L.

[0039] In some embodiments, the stabilizer may include any one or a combination of two or more of acetic acid, citric acid, oxalic acid, ethylenediaminetetraacetic acid (EDTA), phosphoric acid, etc., but is not limited thereto.

[0040] In some more preferred embodiments, the volume of the stabilizer accounts for 0.01% to 15% of the total volume of the mixed reaction system. Specifically, the upper limit of the volume ratio of the added stabilizer to the total volume can be independently selected from any one of 15%, 14%, 13%, 12%, 11%, 10%, 9%, 8%, 7%, 6%, 5%, 4%, 3%, 2%, 1%, 0.9%, 0.8%, 0.7%, 0.6%, 0.5%, 0.4%, 0.3%, 0.2%, and 0.1%; the lower limit can be independently selected from any one of 0.01%, 0.02%, 0.03%, 0.04%, 0.05%, 0.06%, 0.07%, 0.08%, and 0.09%.

[0041] In some embodiments, the modifier may include any one or a combination of two or more of aluminum salts, tin salts, chromium salts, zinc salts, silicon dioxide, etc., but is not limited thereto.

[0042] In some more specific embodiments, the aluminum salt may include any one or a combination of two or more of aluminum chloride, aluminum nitrate, aluminum sulfate, etc., but is not limited thereto; the tin salt may include any one or a combination of two or more of tin chloride, tin nitrate, tin sulfate, etc., but is not limited thereto; the chromium salt may include any one or a combination of two or more of chromium chloride, chromium nitrate, chromium sulfate, etc., but is not limited thereto; the zinc salt may include any one or a combination of two or more of zinc chloride, zinc nitrate, zinc sulfate, etc., but is not limited thereto.

[0043] In some embodiments, the molar ratio of the modifier to terephthalic acid (ie, the concentration ratio in the mixed reaction system) is 1:0.1 to 1:20.

[0044] In some more preferred embodiments, the molar ratio of the modifier to terephthalic acid (ie, the concentration ratio in the mixed reaction system) is 1:5 to 1:20.

[0045] In some embodiments, the first organic solvent may include any one or a combination of two or more of N,N-dimethylformamide (DMF), dimethyl sulfoxide (DMSO), N-methylpyrrolidone, acetone, etc., but is not limited thereto.

[0046] In some embodiments, the preparation method further comprises: filtering the modified MOFs precursor obtained by the dynamic crystallization reaction at a high speed, washing, and drying the modified MOFs precursor to obtain a dried modified MOFs precursor.

[0047] In some specific embodiments, the method for preparing the modified MOFs support may include the following steps: uniformly dissolving terephthalic acid and a zirconium salt in a first organic solvent containing a stabilizer; and subjecting the modified agent to a dynamic crystallization reaction to produce a modified MOFs precursor. The modified MOFs precursor produced by the dynamic crystallization reaction is centrifuged at 700-1200 rpm for 5-30 minutes, filtered, washed, dried, and then vacuum activated at a specified temperature to produce the modified MOFs support. The washing step includes first washing with DMF 3-5 times and then washing with acetone 3-5 times; the drying step is performed at a temperature of 60-80°C for 6-12 hours.

[0048] In some specific embodiments, the present invention utilizes a dynamic crystallization process to ensure that the resulting modified MOF precursor has a uniform and stable morphology. The present invention utilizes a dynamic crystallization process in the preparation of the modified MOF support, ensuring uniform and stable morphology during the formation process while enabling precise control of pore size.

[0049] In some more preferred embodiments, the dynamic crystallization reaction includes: heating the mixed reaction system from room temperature to a specified crystallization reaction temperature at a heating rate of 0.5 to 10°C / min for a dynamic crystallization reaction; wherein the specified crystallization reaction temperature is 80 to 160°C, the time for the dynamic crystallization reaction at the specified crystallization reaction temperature is 6 to 96 hours, and the mechanical flip speed of the dynamic crystallization is 10 to 60 rpm.

[0050] Furthermore, the upper limit of the specified crystallization reaction temperature can be independently selected from 160°C, 155°C, 150°C, 145°C, 140°C, 135°C, 130°C, 125°C, 120°C, 115°C, 110°C, 105°C, 100°C, 95°C, and 90°C, and the lower limit can be independently selected from 89°C, 88°C, 87°C, 86°C, 85°C, 84°C, 83°C, 82°C, 81°C, and 80°C.

[0051] Furthermore, the upper limit of the crystallization reaction time can be independently selected from 96h, 84h, 72h, 60h, 48h, 36h, 24h, and 12h, and the lower limit can be independently selected from 11h, 10h, 9h, 8h, 7h, and 6h.

[0052] In some specific embodiments, the dried modified MOFs precursor is subjected to vacuum activation treatment under vacuum conditions, wherein the vacuum activation treatment temperature is 80 to 200° C., the vacuum activation treatment time is 6 to 96 hours, and the activation vacuum degree is -0.01 to -0.1 MPa.

[0053] Furthermore, the upper limit of the vacuum activation treatment temperature can be independently selected from 200°C, 190°C, 180°C, 170°C, 160°C, 150°C, 140°C, 130°C, 120°C, 110°C, 100°C, 95°C, 90°C, and the lower limit is independently selected from 89°C, 88°C, 87°C, 86°C, 85°C, 84°C, 83°C, 82°C, 81°C, 80°C.

[0054] Furthermore, the upper limit of the vacuum activation treatment time is independently selected from 96h, 90h, 84h, 78h, 72h, 66h, 60h, 54h, 48h, 42h, 36h, 30h, 24h, and the lower limit is independently selected from 22h, 20h, 18h, 16h, 14h, 12h, 10h, 8h, 6h.

[0055] As another aspect of the technical solution of the present invention, it also relates to a modified MOFs carrier prepared by the aforementioned method.

[0056] In some preferred embodiments, the modified MOFs carrier has a particle size of 200 nm to 250 nm and a specific surface area of ​​1200 to 1300 m 2 / g, the crystal form is octahedral.

[0057] The modified MOFs carrier prepared by the present invention has excellent heat resistance and chemical stability, and can still maintain the stability of its morphology during repeated use, so as to achieve better catalyst recycling.

[0058] The surface of the modified MOFs carrier prepared in the present invention is modified, and the modified atoms precisely fill the O vacancies in the special geometric spatial configuration formed by Zr-O to achieve the regulation of the L acid sites in the carrier, enhance the adsorption of HMF molecules by the carrier during the hydrogenation reaction, and enable HMF molecules to contact the hydrogenation sites more, better, and faster to achieve efficient conversion and hydrogenation.

[0059] Furthermore, the modified MOFs support prepared by the present invention creates close contact between the modified atom-enhanced L-acid sites and the metal nanoparticles, shortening the physical distance between them. The efficient synergistic effect of the metal and acid accelerates the diffusion rate between the active sites of the reactants, thereby improving reaction rate and selectivity. Furthermore, due to the close proximity between the metal and the acid, the metal nanoparticles in the modified MOFs-supported catalyst are less likely to fall off during repeated reactions under prolonged high-temperature conditions than traditional supported catalysts, and their performance remains unchanged after high-temperature regeneration, effectively reducing costs.

[0060] As another aspect of the technical solution of the present invention, a method for preparing a supported catalyst includes:

[0061] The modified MOFs support was prepared according to the aforementioned preparation method;

[0062] The metal elements are loaded on the modified MOFs carrier, and then calcined and reduced in sequence to obtain a loaded catalyst.

[0063] In some embodiments, the metal element includes a transition metal element, and the transition metal element may include any one or a combination of two or more of Cu, Ni, Co, Fe, etc., but is not limited thereto.

[0064] In some specific embodiments, the preparation method includes: fully immersing the modified MOFs support in a metal salt solution, thereby loading the metal element on the modified MOFs support.

[0065] Furthermore, the metal salt may include any one or a combination of two or more of transition metal sulfates, transition metal nitrates, transition metal acetates, transition metal phosphates, transition metal chlorides, etc., but is not limited thereto.

[0066] In some embodiments, the preparation method includes: in an inert atmosphere, gradually increasing the temperature of the modified MOFs carrier loaded with metal elements to a calcination temperature, and performing the calcination treatment.

[0067] Furthermore, the inert atmosphere may include a nitrogen atmosphere, but is not limited thereto.

[0068] In some more specific embodiments, the preparation method comprises: heating from room temperature to a specified calcination temperature of 200-500°C at a heating rate of 0.5-10°C / min, and performing calcination at the specified calcination temperature for 1 hour to 20 hours.

[0069] Furthermore, the upper limit of the calcination temperature can be independently selected from 500°C, 450°C, 400°C, 350°C, 300°C, and 250°C, and the lower limit can be independently selected from 250°C, 240°C, 230°C, 220°C, 210°C, and 200°C.

[0070] Furthermore, the upper limit of the calcination time can be independently selected from 20h, 18h, 16h, 14h, 12h, and 10h, and the lower limit can be independently selected from 8h, 6h, 4h, 2h, and 1h.

[0071] In some embodiments, the preparation method includes: performing the reduction treatment on the calcined product in a reducing atmosphere.

[0072] Furthermore, the reducing atmosphere includes a hydrogen atmosphere, but is not limited thereto.

[0073] In some more specific embodiments, the preparation method includes: reducing in a hydrogen atmosphere, raising the reduction temperature from room temperature to a specified reduction temperature of 100 to 600°C at a heating rate of 0.5 to 10°C / min, and performing the reduction treatment at the specified reduction temperature for 1 hour to 30 hours.

[0074] Furthermore, the upper limit of the temperature of the reduction treatment under hydrogen atmosphere can be independently selected from 600°C, 550°C, 500°C, 450°C, 400°C, 350°C, 300°C, 250°C, and 200°C, and the lower limit can be independently selected from 150°C, 140°C, 130°C, 120°C, 110°C, and 100°C.

[0075] Furthermore, the upper limit of the reduction treatment time under hydrogen atmosphere can be independently selected from 30h, 28h, 26h, 24h, 22h, 20h, 18h, 16h, 14h, 12h, 10h, and the lower limit can be independently selected from 10h, 8h, 6h, 4h, 2h, 1h.

[0076] Among them, as one of the more specific embodiments, the preparation method of the supported catalyst with the modified MOFs as the carrier specifically includes the following steps:

[0077] Terephthalic acid and a zirconium salt are uniformly dissolved in a first organic solvent containing a stabilizer. Under the action of a modifier, a dynamic crystallization reaction occurs to produce a modified precursor. After centrifugation, the precursor is washed and dried, and then vacuum-activated at a specified temperature to produce a modified MOFs support. The saturated adsorption capacity of the prepared modified MOFs support is measured, and then the metal salt is dissolved in water at this saturated adsorption capacity and loaded onto the modified MOFs support via an equal volume impregnation method. After drying, the catalyst is calcined at a gradient temperature under a nitrogen atmosphere, followed by a gradient temperature reduction treatment under a hydrogen atmosphere to produce a supported catalyst with the modified MOFs as the support.

[0078] Furthermore, the saturated water absorption capacity of the carrier in the catalyst is the amount of water that the carrier absorbs until the surface is just soaked in water in a dry state.

[0079] In summary, the method for preparing the catalyst of the present invention has a simple loading method, is easy to operate, can be adaptively adjusted according to actual conditions, has strong operability, is low in price, is simple to synthesize, and is safe and reliable. The loaded metal nanoparticles are evenly dispersed due to the porosity and orderliness of the carrier, which can promote substrate transfer within the catalyst, thereby greatly improving the selectivity and yield of catalytic hydrogenation reduction to prepare 2,5-furan dimethanol.

[0080] As another aspect of the technical solution of the present invention, it also relates to a supported catalyst prepared by the aforementioned method, which includes a modified MOFs carrier and metal nanoparticles uniformly supported on the modified MOFs carrier.

[0081] In some embodiments, the loading amount of the metal nanoparticles on the modified MOFs carrier is 0.1 wt % to 20 wt %.

[0082] Furthermore, the upper limit of the metal nanoparticle loading can be independently selected from 20%, 15%, 10%, 5%, and 1%, and the lower limit can be independently selected from 1%, 0.5%, 0.4%, 0.3%, 0.2%, and 0.1%.

[0083] Furthermore, the material of the loaded metal nanoparticles is selected from transition metal elements; the transition metal elements are selected from any one or a combination of two or more of Cu, Ni, Co, Fe, etc.

[0084] The catalyst prepared by the present invention is very stable in thermal reactions under various types of solvents. The special spatial geometric configuration formed by Zr-O and modified atoms has a large number of catalytic sites and porous structures distributed in its skeleton, which is conducive to increasing the contact area between the reactants and the catalytic active sites, thereby promoting the reaction. Secondly, it has a multi-level pore structure and a large window, with an extremely high specific surface area and a hierarchical porous structure, which can better stabilize the metal nanoparticles and can effectively help transport the reaction substrates in the catalytic reaction. It is used for heterogeneous catalytic reactions and has the advantages of both homogeneous catalysts and traditional heterogeneous catalysts. Moreover, according to the reaction requirements, organic ligands with different functional groups can be selected to modify the carrier to allow it to have catalysts with different functional group efficacies.

[0085] Furthermore, compared to traditional supported catalysts, the catalyst prepared by the present invention is highly reusable, less prone to deactivation, and exhibits very high selectivity, strong specificity, and excellent regeneration. The catalyst can be washed and reused after the reaction, maintaining its performance, reducing operational costs and offering promising application prospects.

[0086] Another aspect of the embodiments of the present invention further provides use of the aforementioned supported catalyst using the modified MOFs as a carrier in the preparation of 2,5-furandicarboxylic acid.

[0087] Specifically, the application includes the use of the supported catalyst in the hydrogenation of 5-hydroxymethylfurfural to prepare 2,5-furan dimethanol.

[0088] Accordingly, another aspect of an embodiment of the present invention provides a method for preparing 2,5-furan dimethanol, comprising:

[0089] 5-Hydroxymethylfurfural is used as a raw material, a second organic solvent is used as a reaction solvent, a supported catalyst with modified MOFs as a carrier is added, and the 2,5-furan dimethanol is prepared by a catalytic hydrogenation reaction under a hydrogen pressure atmosphere.

[0090] In some preferred embodiments, the preparation method specifically comprises: mixing the supported catalyst, 5-hydroxymethylfurfural and a second organic solvent to form a reaction solution.

[0091] In some specific embodiments, the concentration of 5-hydroxymethylfurfural in the reaction solution is 0.1 to 3000 mmol / L.

[0092] Furthermore, the upper limit of the concentration of 5-hydroxymethylfurfural in the reaction solution can be independently selected from 3000mM, 2500mM, 2000mM, 1500mM, 1000mM, 500mM, 400mM, 300mM, 200mM, and 100mM, and the lower limit can be independently selected from 0.1mM, 0.5mM, 1mM, 5mM, 10mM, 20mM, 30mM, 40mM, 50mM, 60mM, 70mM, 80mM, and 90mM.

[0093] In some specific embodiments, the second organic solvent may include any one or a combination of two or more of methanol, ethanol, n-propanol, isopropanol, n-butanol, etc., but is not limited thereto.

[0094] In some specific embodiments, the pressure of the hydrogen is 0.1 MPa to 8 MPa.

[0095] Furthermore, the upper limit of the hydrogen pressure can be independently selected from 8 MPa, 7 MPa, 6 MPa, 5 MPa, 4 MPa, 3 MPa, and 2 MPa, and the lower limit can be independently selected from 1 MPa, 0.8 MPa, 0.6 MPa, 0.4 MPa, 0.2 MPa, and 0.1 MPa.

[0096] In some specific embodiments, the temperature of the catalytic hydrogenation reaction is 80-200° C., and the time of the catalytic hydrogenation reaction is 0.5-10 h.

[0097] Furthermore, the upper limit of the temperature of the catalytic hydrogenation reaction can be independently selected from 200°C, 190°C, 180°C, 170°C, 160°C, 150°C, 140°C, 130°C, 120°C, and 110°C, and the lower limit can be independently selected from 105°C, 100°C, 95°C, 90°C, 85°C, and 80°C.

[0098] In some specific embodiments, the mass ratio of the 5-hydroxymethylfurfural to the supported catalyst is 1:1 to 30:1.

[0099] Furthermore, the upper limit of the mass ratio of the 5-hydroxymethylfurfural to the supported catalyst is independently selected from any one of 30:1, 29:1, 28:1, 27:1, 26:1, 25:1, 24:1, 23:1, 22:1, 21:1, 20:1, 19:1, 18:1, 17:1, 16:1, 15:1, 14:1, 13:1, 12:1, 11:1, 10:1, 9:1, 8:1, 7:1, 6:1, and 5:1; the lower limit is independently selected from any one of 1:1, 1.2:1, 1.4:1, 1.6:1, 1.8:1, 2:1, 2.2:1, 2.4:1, 2.6:1, 2.8:1, 3:1, 3.2:1, 3.4:1, 3.6:1, 3.8:1, and 4:1.

[0100] Furthermore, the reaction process for preparing 2,5-furan dimethanol according to the present invention has a very high conversion rate, is controllable (by changing different reaction condition parameters), has very strong selectivity, avoids interference from various intermediate products, effectively improves the reaction yield, reduces the difficulty of separation, and improves the yield.

[0101] Through the above technical solution, the process for preparing a supported catalyst using modified MOFs as a carrier is simple, safe and reliable. At the same time, when the metal-supported catalyst is used to prepare 2,5-furan dimethanol, it has strong controllability, strong reaction activity, high selectivity, good reusability, good renewability, and is safe and pollution-free.

[0102] The technical solution of the present invention will be further described in detail below in conjunction with several embodiments and drawings. This embodiment is implemented on the premise of the technical solution of the invention, and provides a detailed implementation method and specific operation process, but the protection scope of the present invention is not limited to the following embodiments.

[0103] Unless otherwise specified, the experimental materials used in the following examples can be purchased from conventional biochemical reagent companies.

[0104] The analysis method in the embodiment of the present invention is as follows:

[0105] In the examples, the products of the 5-hydroxymethylfurfural synthesis reaction were analyzed using an Agilent LC1260 high performance liquid chromatograph, and the external standard method was used for quantification.

[0106] Time-of-flight mass spectrometry (TOF) was used to qualitatively analyze the products in the 5-hydroxymethylfurfural synthesis reaction.

[0107] X-ray powder diffractometer (XRD) was used to qualitatively analyze the prepared supported catalyst with modified MOFs as the carrier.

[0108] Transmission electron microscopy (TEM) was used to characterize the morphology of the prepared modified MOFs carrier and the metal particles supported by the supported catalyst based on the modified MOFs.

[0109] Scanning electron microscopy (SEM) was used to characterize the morphology of the prepared modified MOFs carrier and the metal particles supported by the supported catalyst based on the modified MOFs.

[0110] X-ray photoelectron spectroscopy (XPS) was used to qualitatively and quantitatively analyze the chemical state of the metal particles supported by the prepared modified MOFs supported catalyst.

[0111] Inductively coupled plasma optical emission spectrometry (ICP-OES) was used to qualitatively and quantitatively analyze the metal loading of the prepared modified MOFs supported catalyst.

[0112] The specific surface area of ​​the supported catalyst with the prepared modified MOFs as the carrier was qualitatively and quantitatively analyzed using a specific surface area adsorption instrument.

[0113] The calculation method in the embodiments of the present application is as follows:

[0114] The calculation formulas for catalyst selectivity, 5-hydroxymethylfurfural conversion rate and 2,5-furan dimethanol yield are as follows:

[0115] 2,5-furandimethanol yield = (mass of 2,5-furandimethanol in the product / theoretical mass of 2,5-furandimethanol produced) × 100%;

[0116] 5-Hydroxymethylfurfural conversion rate = (mass of 5-Hydroxymethylfurfural actually involved in the reaction / mass of 5-Hydroxymethylfurfural in the raw material) × 100%;

[0117] Catalyst selectivity = (2,5-furan dimethanol yield / 5-hydroxymethylfurfural conversion rate) × 100%.

[0118] Example 1

[0119] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.038g of modifier anhydrous AlCl3, stir thoroughly until completely dissolved. At this point, the volume of the stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and Zr 4+ The concentration ratio of PTA and modifier Al is 1.05:1. 3+The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical rotation speed was 30 rpm.

[0120] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0121] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was designated as 1#. The morphology of sample 1# was scanned by transmission electron microscopy (TEM), and the results showed that Figure 1a and Figure 1b shown.

[0122] Example 2

[0123] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.076g of modifier anhydrous AlCl3, stir thoroughly until completely dissolved. At this point, the volume of the stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and Zr 4+ The concentration ratio of PTA and modifier Al is 1.05:1. 3+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical turning speed was 30 rpm.

[0124] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0125] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 2#.

[0126] Compared with Example 1, Example 2 has a different amount of modifier added during the preparation of the carrier, which increases the amount of modifier. The modified MOFs prepared under these conditions are used as the support to prepare a supported catalyst.

[0127] Example 3

[0128] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.019g of modifier anhydrous AlCl3, stir thoroughly until completely dissolved. At this point, the volume of stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and Zr 4+ The concentration ratio of PTA and modifier Al is 1.05:1. 3+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical rotation speed was 30 rpm.

[0129] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0130] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 3#.

[0131] Compared with Example 1, the amount of modifier added during the preparation of the carrier in Example 3 is different, so that the amount of modifier is reduced. The modified MOFs prepared under these conditions are used as the support to prepare a supported catalyst.

[0132] Comparative Example 1

[0133] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA and 0.631g of zirconium chloride respectively, stir thoroughly until completely dissolved. At this point, the volume of the stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and Zr 4+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical rotation speed was 30 rpm.

[0134] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the MOFs precursor.

[0135] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a MOFs carrier, which was designated as 4#.

[0136] Compared with Example 1, in this comparative example, no modifier was added to modify the support during the preparation process of the support. The MOFs prepared under these conditions were used as the support to prepare a supported catalyst.

[0137] Example 4

[0138] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.017g of modifier SiO2, stir thoroughly until completely dissolved. At this point, the volume of stabilizer in the system accounts for 5.5% of the total system, and PTA and Zr 4+ The concentration ratio of PTA and modifier Si is 1.05:1. 4+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical rotation speed was 30 rpm.

[0139] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0140] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 5#.

[0141] Example 4 Compared with Example 1, this example changes the type of modifier for the crystallization reaction during the preparation of the carrier, and the modified atom is Al 3+ Changed to Si 4+ The modified MOFs prepared under these conditions were used as the loading carrier to prepare a supported catalyst.

[0142] Example 5

[0143] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.074g of anhydrous SnCl4 as modifier, stir thoroughly until completely dissolved. At this point, the volume of stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and ZrCl4 is 1.5%. 4+The concentration ratio of PTA and modifier Sn is 1.05:1. 4+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical rotation speed was 30 rpm.

[0144] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0145] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 6#.

[0146] Example 5 Compared with Example 1, the type of modifier for the crystallization reaction was changed during the preparation of the carrier in this example. The modified atom was Al 3+ Changed to Sn 4+ The modified MOFs prepared under these conditions were used as the loading carrier to prepare a supported catalyst.

[0147] Comparative Example 2

[0148] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.038g of modifier anhydrous AlCl3, stir thoroughly until completely dissolved. At this point, the volume of the stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and Zr 4+ The concentration ratio of PTA and modifier Al is 1.05:1. 3+ The concentration ratio of is 10: 1. The reaction solution is poured into a hydrothermal reactor for crystallization reaction, and the temperature is raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 1°C / min, and the crystallization reaction time is 24h.

[0149] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0150] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 7#.

[0151] Compared with Example 1, the crystallization reaction in this comparative example is a static crystallization process. The modified MOFs prepared under these conditions are used as a support to prepare a supported catalyst. The morphology of sample 7# was scanned by scanning electron microscope (SEM). The results showed that Figure 2 shown.

[0152] Example 6

[0153] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.038g of modifier anhydrous AlCl3, stir thoroughly until completely dissolved. At this point, the volume of the stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and Zr 4+ The concentration ratio of PTA and modifier Al is 1.05:1. 3+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 80°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical turning speed was 30 rpm.

[0154] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0155] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 8#.

[0156] Compared with Example 1, in this example, the temperature of the crystallization reaction was changed during the preparation process, and the crystallization reaction temperature was slightly lowered. The modified MOFs prepared under this condition were used as the loading carrier to prepare a loaded catalyst.

[0157] Example 7

[0158] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.038g of modifier anhydrous AlCl3, stir thoroughly until completely dissolved. At this point, the volume of the stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and Zr 4+ The concentration ratio of PTA and modifier Al is 1.05:1. 3+The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 160°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical rotation speed was 30 rpm.

[0159] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0160] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 9#.

[0161] Compared with Example 1, in this example, the temperature of the crystallization reaction is changed during the preparation process, and the crystallization reaction temperature is slightly increased. The modified MOFs prepared under this condition are used as the loading carrier to prepare a loaded catalyst.

[0162] Example 8

[0163] (1) Add 188ml of DMF and 12ml of stabilizer acetic acid to a 250ml beaker, stir evenly, then add 0.473g of PTA, 0.631g of zirconium chloride and 0.038g of modifier anhydrous AlCl3, stir thoroughly until completely dissolved. At this point, the volume of the stabilizer in the system accounts for 5.5% of the total system, and the volume of PTA and Zr 4+ The concentration ratio of PTA and modifier Al is 1.05:1. 3+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 5°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical rotation speed was 30 rpm.

[0164] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0165] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 10#.

[0166] Compared to Example 1, Example 8 varied the heating rate to the designated crystallization temperature during the preparation process, accelerating the crystallization temperature. The crystallization heating rate was increased from 1°C / min to 5°C / min. All other conditions remained unchanged. The modified MOFs prepared under these conditions served as a support to prepare a supported catalyst.

[0167] Comparative Example 3

[0168] (1) Add 188ml of DMF solvent, 0.473g of PTA, 0.631g of zirconium chloride and 0.038g of anhydrous AlCl3 to a 250ml beaker and stir until they are completely dissolved. 4+ The concentration ratio of PTA and modifier Al is 1.05:1. 3+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 120°C at a heating rate of 1°C / min. The crystallization reaction time was 24 hours, and the dynamic crystallization mechanical rotation speed was 30 rpm.

[0169] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1000 rpm for 10 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 80 °C for 6 h to obtain the modified MOFs precursor.

[0170] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 120°C and a vacuum degree of -0.1PMa for 24 hours to obtain a modified MOFs carrier, which was recorded as 11#.

[0171] Compared with Example 1, in this comparative example, no stabilizer was added to regulate the formation of crystals during the preparation of the carrier. The modified MOFs prepared under these conditions were used as the supporting carrier to prepare a supported catalyst.

[0172] Example 9

[0173] The difference between this embodiment and embodiment 1 is that: (1) the carboxylate ligand is tribenzoic acid, the stabilizer is citric acid, and the volume of the stabilizer accounts for 5% of the total volume of the mixed reaction system. 4+ The concentration ratio of tribenzoic acid and modifier Al is 0.1:1. 3+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 160°C at a heating rate of 10°C / min. The crystallization reaction time was 6 hours, and the dynamic crystallization mechanical turning speed was 60 rpm.

[0174] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 1200 rpm for 5 min, filtered, washed with DMF 3-5 times, and then with acetone 3-5 times, and dried at 70 °C for 10 h to obtain the modified MOFs precursor.

[0175] (3) The modified MOFs precursor is placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 80°C and a vacuum degree of -0.1PMa for 96 hours to obtain a modified MOFs carrier.

[0176] Example 10

[0177] Compared with Example 1, the differences of this embodiment are as follows: (1) the carboxylate ligand is naphthalene dicarboxylic acid, the stabilizer is oxalic acid, and the volume of the stabilizer accounts for 10% of the total volume of the mixed reaction system. 4+ The concentration ratio of naphthalene dicarboxylic acid and modifier Al is 5:1. 3+ The reaction solution was poured into a hydrothermal kettle and placed in an automatic homogeneous reactor for dynamic crystallization reaction. The temperature was raised from room temperature to the designated crystallization reaction temperature of 80°C at a heating rate of 0.5°C / min. The crystallization reaction time was 96 hours, and the dynamic crystallization mechanical rotation speed was 10 rpm.

[0178] (2) After the crystallization reaction is completed, the product is cooled to room temperature, centrifuged at 700 rpm for 30 min, filtered, washed with DMF 3-5 times, then with acetone 3-5 times, and dried at 60 °C for 12 h to obtain the modified MOFs precursor.

[0179] (3) The modified MOFs precursor was placed in a vacuum drying oven for vacuum activation treatment at an activation temperature of 200°C and a vacuum degree of -0.01PMa for 6 hours to obtain the modified MOFs carrier.

[0180] Example 11

[0181] Compared with Example 1, this embodiment differs in that the carboxylate ligand is biphenyl-4,4-dicarboxylic acid, the stabilizer is oxalic acid, and the volume of the stabilizer accounts for 10% of the total volume of the mixed reaction system.

[0182] Example 12

[0183] Compared with Example 1, this embodiment differs in that the stabilizer is ethylenediaminetetraacetic acid, and the volume of the stabilizer accounts for 15% of the total volume of the mixed reaction system.

[0184] Example 13

[0185] Compared with Example 1, this embodiment differs in that the stabilizer is phosphoric acid, and the volume of the stabilizer accounts for 0.1% of the total volume of the mixed reaction system.

[0186] Example 14

[0187] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0188] (1) Determination of saturated water absorption: Place 1 g of dried modified MOFs support #1 in a beaker and slowly and evenly add deionized water until the modified MOFs support is saturated with water and the surface of the modified MOFs support is just soaked. The amount of water adsorbed by the modified MOFs support at this point is the saturated water absorption of the support, and the saturated water absorption is 2 ml.

[0189] (2) Add 2 ml of water and 0.202 g of copper nitrate trihydrate to a beaker and dissolve thoroughly to prepare a Cu(NO3)2 solution. Using the equal volume impregnation method, slowly pour 1 g of 1# modified MOFs support particles into the prepared Cu(NO3)2 solution to mix the liquid and powder evenly. Then, leave it open in the air for 48 hours until the surface is completely dry.

[0190] (3) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 1°C / min from room temperature to 300°C. It was calcined at this specified temperature for 3 h, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0191] (4) Then, the sample was subjected to a gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 1°C / min from room temperature to 300°C, and reduced at the specified temperature for 3 hours to obtain a modified Cu-MOFs supported catalyst with a Cu content of 5 wt%, denoted as 1-1#. The XPS valence state characterization of sample 1-1# showed that Figure 3 As shown. TEM scanning of sample 1-1# shows the following Figure 4 As shown in the particle size analysis diagram Figure 5b shown.

[0192] Example 15

[0193] The 2# modified MOFs carrier prepared in Example 2 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-2#.

[0194] Example 16

[0195] The 3# modified MOFs carrier prepared in Example 3 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-3#.

[0196] Comparative Example 4

[0197] The 4# modified MOFs carrier prepared in Comparative Example 1 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-4#.

[0198] Example 17

[0199] The 5# modified MOFs carrier prepared in Example 4 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-5#.

[0200] Example 18

[0201] The 6# modified MOFs carrier prepared in Example 5 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-6#.

[0202] Comparative Example 5

[0203] The 7# modified MOFs carrier prepared in Comparative Example 2 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-7#.

[0204] Example 19

[0205] The 8# modified MOFs carrier prepared in Example 6 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-8#.

[0206] Example 20

[0207] The 9# modified MOFs carrier prepared in Example 7 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-9#.

[0208] Example 21

[0209] The 10# modified MOFs carrier prepared in Example 8 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst, with a Cu content of 5 wt%, recorded as 1-10#.

[0210] Comparative Example 6

[0211] The 11# modified MOFs carrier prepared in Comparative Example 3 was selected as the support, and the same loading method as in Example 14 was adopted to prepare a modified Cu-MOFs supported catalyst with a Cu content of 5 wt%, recorded as 1-11#.

[0212] Example 22

[0213] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0214] (1) Add 2 ml of water and 0.099 g of copper nitrate trihydrate to a beaker and dissolve them fully to prepare a Cu(NO3)2 solution. Load the solution onto the 1# modified MOFs carrier by an equal volume impregnation method. Subsequently, the same loading method as in Example 14 was used to obtain a modified Cu-MOFs supported catalyst with a Cu content of 2.5 wt%, designated as 2-1#. XRD characterization of the oxidation state of sample 2-1# showed that Figure 6 shown.

[0215] Example 22 Compared with Example 14, the metal loading of the supported catalyst prepared in this example was changed to 2.5 wt%. XPS valence state characterization of the reduced state of sample 2-1# was performed, and the results showed that Figure 3 As shown. The particle size analysis of sample 2-1# is shown in the figure below. Figure 5a shown.

[0216] Example 23

[0217] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0218] (1) Add 2 ml of water and 0.311 g of copper nitrate trihydrate to a beaker and dissolve thoroughly to prepare a Cu(NO3)2 solution. Load the solution onto the modified MOFs support #1 by an equal volume impregnation method. Subsequently, the same loading method as in Example 14 was used to prepare a modified Cu-MOFs supported catalyst with a Cu content of 7.5 wt%, designated as 3-1#.

[0219] Example 23 Compared with Example 14, the metal loading of the supported catalyst prepared in this example was changed to 7.5 wt%. XPS valence characterization of the reduced state of sample 3-1# was performed, and the results showed that Figure 3 As shown. The particle size analysis chart of sample 3-1# is as follows Figure 5c shown.

[0220] Example 24

[0221] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0222] Add 2 ml of water and 0.427 g of copper nitrate trihydrate to a beaker and fully dissolve to prepare a Cu(NO3)2 solution. Load the solution onto the modified MOFs support #1 by an equal volume impregnation method. Subsequently, the same loading method as in Example 14 was used to prepare a modified Cu-MOFs-supported catalyst with a Cu content of 10 wt%, designated as 4-1#.

[0223] Example 24 Compared with Example 14, the metal loading of the supported catalyst prepared in this example was changed to 10 wt%. XPS valence state characterization of the reduced state of sample 4-1# was performed, and the results showed that Figure 3 As shown. The particle size analysis of sample 4-1# is shown in the figure below. Figure 5d shown.

[0224] Example 25

[0225] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0226] (1) Add 2 ml of water and 0.243 g of nickel nitrate hexahydrate to a beaker and dissolve them thoroughly to prepare a Ni(NO3)2 solution. Using the equal volume impregnation method, slowly pour 1 g of 1# modified MOFs support particles into the prepared Ni(NO3)2 solution to mix the liquid and powder evenly. Then, leave it open in the air for 48 hours until the surface is completely dry.

[0227] (2) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 1°C / min from room temperature to 300°C. It was calcined at this specified temperature for 3 h, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0228] (3) Then, the modified Ni-MOFs supported catalyst was prepared by gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 1°C / min from room temperature to 300°C, and the catalyst was reduced at the specified temperature for 3 h. The Ni content was 5 wt%, and was recorded as 5-1#.

[0229] Compared with Example 14, the supported catalyst prepared in Example 25 has a different type of supported metal.

[0230] Example 26

[0231] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0232] (1) Add 2 ml of water and 0.202 g of copper nitrate trihydrate to a beaker and dissolve thoroughly to prepare a Cu(NO3)2 solution. Using the equal volume impregnation method, slowly pour 1 g of 1# modified MOFs support particles into the prepared Cu(NO3)2 solution to mix the liquid and powder evenly. Then, leave it open in the air for 48 hours until the surface is completely dry.

[0233] (2) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 5°C / min from room temperature to 300°C. It was calcined at this specified temperature for 3 h, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0234] (3) Then, the modified Cu-MOFs supported catalyst was prepared by gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 1°C / min from room temperature to 300°C, and the catalyst was reduced at this specified temperature for 3 h. The mass content of Cu was 5 wt%, and was recorded as 6-1#.

[0235] Compared with Example 14, the supported catalyst prepared in this example changed the heating rate to the specified calcination temperature during the preparation process.

[0236] Example 27

[0237] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0238] (1) Add 2 ml of water and 0.202 g of copper nitrate trihydrate to a beaker and dissolve thoroughly to prepare a Cu(NO3)2 solution. Using the equal volume impregnation method, slowly pour 1 g of 1# modified MOFs support particles into the prepared Cu(NO3)2 solution to mix the liquid and powder evenly. Then, leave it open in the air for 48 hours until the surface is completely dry.

[0239] (2) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 1°C / min from room temperature to 500°C. It was calcined at this specified temperature for 3 h, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0240] (3) Then, the modified Cu-MOFs supported catalyst was prepared by gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 1°C / min from room temperature to 300°C, and the catalyst was reduced at this specified temperature for 3 h. The mass content of Cu was 5 wt%, and it was recorded as 7-1#.

[0241] Compared with Example 14, the calcination temperature of the supported catalyst prepared in Example 27 was changed from 300°C to 500°C.

[0242] Example 28

[0243] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0244] (1) Add 2 ml of water and 0.202 g of copper nitrate trihydrate to a beaker and dissolve thoroughly to prepare a Cu(NO3)2 solution. Using the equal volume impregnation method, slowly pour 1 g of 1# modified MOFs support particles into the prepared Cu(NO3)2 solution to mix the liquid and powder evenly. Then, leave it open in the air for 48 hours until the surface is completely dry.

[0245] (2) The sample is then placed in an oven and dried until completely dry. Finally, the sample is placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 1°C / min from room temperature to 200°C. It is calcined at this specified temperature for 3 hours, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0246] (3) Then, the modified Cu-MOFs supported catalyst was prepared by gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 1°C / min from room temperature to 200°C, and the catalyst was reduced at the specified temperature for 3 h. The mass content of Cu was 5 wt%, and it was recorded as 8-1#.

[0247] Compared with Example 14, the calcination temperature of the supported catalyst prepared in Example 28 was changed from 300°C to 200°C.

[0248] Example 29

[0249] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0250] (1) Add 2 ml of water and 0.202 g of copper nitrate trihydrate to a beaker and dissolve thoroughly to prepare a Cu(NO3)2 solution. Using the equal volume impregnation method, slowly pour 1 g of 1# modified MOFs support particles into the prepared Cu(NO3)2 solution to mix the liquid and powder evenly. Then, leave it open in the air for 48 hours until the surface is completely dry.

[0251] (2) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 1°C / min from room temperature to 300°C. It was calcined at this specified temperature for 3 h, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0252] (3) Then, the catalyst was reduced by gradient temperature increase in a tubular furnace under a hydrogen atmosphere, with the temperature rising from room temperature at a rate of 5°C / min to 300°C, and reduced at this specified temperature for 3 h to obtain a modified Cu-MOFs supported catalyst with a Cu mass content of 5 wt%, recorded as 9-1#.

[0253] Compared with Example 14, when the supported catalyst prepared in Example 29 was reduced in a hydrogen atmosphere, the heating rate to the specified reduction temperature was changed.

[0254] Example 30

[0255] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0256] (1) Add 2 ml of water and 0.202 g of copper nitrate trihydrate to a beaker and dissolve thoroughly to prepare a Cu(NO3)2 solution. Using the equal volume impregnation method, slowly pour 1 g of 1# modified MOFs support particles into the prepared Cu(NO3)2 solution to mix the liquid and powder evenly. Then, leave it open in the air for 48 hours until the surface is completely dry.

[0257] (2) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 1°C / min from room temperature to 300°C. It was calcined at this specified temperature for 3 h, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0258] (3) Then, the modified Cu-MOFs supported catalyst was prepared by gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 1°C / min from room temperature to 600°C, and the catalyst was reduced at this specified temperature for 3 h. The mass content of Cu was 5 wt%, and was recorded as 10-1#.

[0259] Compared with Example 14, when the supported catalyst prepared in Example 30 was reduced in a hydrogen atmosphere, the specified reduction temperature was changed from 300° C. to 600° C.

[0260] Example 31

[0261] Select the 1# modified MOFs carrier prepared in Example 1 as the loading

[0262] (1) Add 2 ml of water and 0.202 g of copper nitrate trihydrate to a beaker and dissolve thoroughly to prepare a Cu(NO3)2 solution. Using the equal volume impregnation method, slowly pour 1 g of 1# modified MOFs support particles into the prepared Cu(NO3)2 solution to mix the liquid and powder evenly. Then, leave it open in the air for 48 hours until the surface is completely dry.

[0263] (2) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 1°C / min from room temperature to 300°C. It was calcined at this specified temperature for 3 h, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0264] (3) Then, the modified Cu-MOFs supported catalyst was prepared by gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 1°C / min from room temperature to 100°C, and the catalyst was reduced at the specified temperature for 3 h. The mass content of Cu was 5 wt%, and was recorded as 11-1#.

[0265] Compared with Example 14, when the supported catalyst prepared in Example 31 was reduced in a hydrogen atmosphere, the specified reduction temperature was changed from 300°C to 100°C.

[0266] Example 32

[0267] Compared with Example 14, this embodiment differs in that:

[0268] (2) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 0.5°C / min from room temperature to 200°C. It was calcined at this specified temperature for 20 h, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported catalyst.

[0269] (3) Then, the modified Cu-MOFs supported catalyst was obtained by gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 0.5°C / min from room temperature to 100°C, and reduction was carried out at the specified temperature for 30 h.

[0270] Example 33

[0271] Compared with Example 14, this embodiment differs in that:

[0272] (2) The sample was then placed in an oven and dried until completely dry. Finally, the sample was placed in a tubular furnace and calcined in a nitrogen atmosphere at a gradient temperature increase rate of 10°C / min from room temperature to 500°C. It was calcined at this specified temperature for 1 hour, and taken out after cooling to obtain a supported catalyst with the oxidized modified MOFs as the supported material.

[0273] (3) Then, the modified Cu-MOFs supported catalyst was obtained by gradient temperature reduction in a tubular furnace under a hydrogen atmosphere, with the temperature rising at a rate of 10°C / min from room temperature to 600°C, and reduction was carried out at the specified temperature for 1 hour.

[0274] Example 34

[0275] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0276] (2) Then, 0.1 g of the 1-1# catalyst prepared in Example 14 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0277] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents in the reaction solution were analyzed by LC. The results are shown in Table 1.

[0278] Table 1 Reaction results of Example 34

[0279]

[0280]

[0281] Example 35

[0282] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0283] (2) 0.1 g of catalyst #1-2 prepared in Example 15 was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C, and the hydrogenation reaction time was 2 h.

[0284] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 2.

[0285] Table 2 Reaction results of Example 35

[0286] Example BHMF yield HMF conversion Catalyst selectivity 35 70 99 71

[0287] Compared to Example 34, Example 35 used a different catalyst sample, from 1-1# to 1-2#. Specifically, the carrier preparation method was modified, and the modifier dosage in the precursor for preparing the modified MOFs carrier was increased; all other preparation conditions remained unchanged. While the HMF conversion rate increased with the increase in modifier dosage, the increased amount of modified atoms resulted in an excessive acid content in the carrier, leading to an over-reaction. This resulted in the target product, BHMF, undergoing excessive etherification in the presence of the acidic catalyst and the solvent, isopropanol. This ultimately affected the selectivity for HMF and the yield of BHMF during the catalytic reaction.

[0288] Example 36

[0289] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0290] (2) 0.1 g of the catalyst #1-3 prepared in Example 16 was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C, and the hydrogenation reaction time was 2 h.

[0291] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents in the reaction solution were analyzed by LC. The results are shown in Table 3.

[0292] Table 3 Reaction results of Example 36

[0293] Example BHMF yield HMF conversion Catalyst selectivity 36 86 91 95

[0294] Compared to Example 34, Example 36 used a different catalyst sample, from 1-1# to 1-3#. Specifically, the carrier preparation method was modified, and the amount of modifier in the precursor for preparing the modified MOFs carrier was reduced. All other preparation conditions remained unchanged. However, the reduction in the number of modifying atoms resulted in a decrease in the acid content of the carrier, slightly reducing its adsorption capacity for HMF molecules and slowing the reaction rate. This ultimately affected its selectivity for HMF and the yield of BHMF during the catalytic reaction.

[0295] Comparative Example 7

[0296] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0297] (2) Then, 0.1 g of the catalyst #1-4 prepared in Comparative Example 4 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0298] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents in the reaction solution were analyzed by LC. The results are shown in Table 4.

[0299] Table 4 Reaction results of Comparative Example 7

[0300] Comparative Example BHMF yield HMF conversion Catalyst selectivity 7 80 86 93

[0301] Comparative Example 7 compared Example 34 with the catalyst sample used in this comparative example. The catalyst sample used was changed from 1-1# to 1-4#. Specifically, the carrier preparation method was modified. No modifier was added to the precursor for the modified MOFs carrier, while all other preparation conditions remained unchanged. The absence of the modifier significantly reduced the carrier's adsorption capacity for HMF molecules, slowing the reaction rate. This affected the selectivity for HMF and the yield of BHMF during the catalytic reaction.

[0302] Example 37

[0303] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0304] (2) Then, 0.1 g of the catalyst #1-5 prepared in Example 17 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0305] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents in the reaction solution were analyzed by LC. The results are shown in Table 5.

[0306] Table 5 Reaction results of Example 37

[0307] Example BHMF yield HMF conversion Catalyst selectivity 37 95 96 99

[0308] Compared with Example 34, the catalyst sample used in Example 37 was changed from 1-1# to 1-5#, that is, the preparation method of the carrier was changed, and the type of modifier added in the precursor of the modified MOFs carrier was changed. The modified atom was changed from Al 3+ Changed to Si 4+ , the other preparation conditions remained unchanged, the conversion rate of HMF decreased slightly and the yield of BHMF increased. This is because Si 4+ The addition of acid is compared with Al 3+ The support has a slight disadvantage, which slightly affects the adsorption capacity of HMF molecules, but it can promote the reducibility of the metal components, thereby enhancing the hydrogenation activity of the catalyst. The final prepared catalyst has improved the selectivity of the catalyst during the catalytic reaction. Therefore, it can be seen that selecting the right modifier to modify the MOF support is the key to affecting the hydrogenation reduction of HMF to BHMF.

[0309] Example 38

[0310] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0311] (2) Then, 0.1 g of the catalyst #1-6 prepared in Example 18 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0312] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 6.

[0313] Table 6 Reaction results of Example 38

[0314] Example BHMF yield HMF conversion Catalyst selectivity 38 95 96 99

[0315] Compared with Example 34, the catalyst sample used in this example has changed from 1-1# to 1-6#, that is, the preparation method of the carrier has changed, and the type of modifier added in the precursor of the modified MOFs carrier has changed. The modified atom is changed from Al 3+ Changed to Sn 4+, the other preparation conditions remained unchanged, and the conversion rate of HMF and the yield of BHMF were both lower than those in Example 34. This shows that selecting a suitable modifier to modify the MOFs support is the key to affecting the hydrogenation reduction of HMF to BHMF.

[0316] Comparative Example 8

[0317] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0318] (2) Then, 0.1 g of the catalyst #1-7 prepared in Comparative Example 5 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and the temperature was programmed to 150°C for 2 h.

[0319] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 7.

[0320] Table 7 Reaction results of Comparative Example 8

[0321] Comparative Example BHMF yield HMF conversion Catalyst selectivity 8 82 94 87

[0322] Comparative Example 8 compared Example 34 with the catalyst sample used in this comparative example. The catalyst sample used was changed from 1-1# to 1-7#, that is, the preparation method of the support was changed. The crystallization reaction method in the precursor for preparing the modified MOFs support was changed from dynamic crystallization to conventional static crystallization. The other preparation conditions remained unchanged. The conversion rate of HMF and the yield of BHMF both decreased. The crystalline arrangement order of the support prepared by static crystallization was worse than that of Example 34. Due to the uneven size of the static crystallized support, the uniform stability of the metal nanoparticles loaded was relatively insufficient. The final catalyst prepared affected its selectivity for HMF and the yield of BHMF during the catalytic reaction. Moreover, the support prepared by static crystallization had high yields in some reactions, low yields in others, and poor reproducibility.

[0323] Example 39

[0324] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0325] (2) Then, 0.1 g of the 1-8# catalyst prepared in Example 19 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0326] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents in the reaction solution were analyzed by LC. The results are shown in Table 8.

[0327] Table 8 Reaction results of Example 39

[0328] Example BHMF yield HMF conversion Catalyst selectivity 39 69 84 82

[0329] Compared to Example 34, Example 39 used a different catalyst sample, from 1-1# to 1-8#. Specifically, the carrier preparation method was modified, and the specified crystallization reaction temperature was changed during the preparation of the modified MOFs carrier, resulting in a lower crystallization reaction temperature. All other preparation conditions remained unchanged. The lower crystallization reaction temperature affected precursor formation, resulting in low dispersion of the metal loading on the carrier during the loading process. This affected the selectivity for HMF and the yield of BHMF in the resulting catalyst during the catalytic reaction.

[0330] Example 40

[0331] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0332] (2) Then, 0.1 g of the catalyst #1-9 prepared in Example 20 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0333] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents in the reaction solution were analyzed by LC. The results are shown in Table 9.

[0334] Table 9 Reaction results of Example 40

[0335] Example BHMF yield HMF conversion Catalyst selectivity 40 78 89 88

[0336] Compared to Example 34, Example 40 used a different catalyst sample, from 1-1# to 1-9#. Specifically, the carrier preparation method was modified, and the specified crystallization reaction temperature was increased during the preparation of the modified MOFs carrier. All other preparation conditions remained unchanged. The increased crystallization reaction temperature caused grain boundary segregation of the precursor during the molding process, which in turn led to the aggregation of the loaded metal atoms at the grain boundaries. This affected the selectivity for HMF and the yield of BHMF in the resulting catalyst during the catalytic reaction.

[0337] Example 41

[0338] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0339] (2) Then, 0.1 g of the 1-10# catalyst prepared in Example 21 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0340] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 10.

[0341] Table 10 Reaction results of Example 41

[0342] Example BHMF yield HMF conversion Catalyst selectivity 41 82 89 92

[0343] Compared to Example 33, Example 41 used a different catalyst sample, changing from 1-1# to 1-10#. This means that the carrier preparation method was modified, and the heating rate required to achieve the specified crystallization reaction was altered during the preparation of the modified MOFs carrier, resulting in a faster heating rate for achieving the specified crystallization reaction. This affected the selectivity for HMF and the yield of BHMF in the resulting catalyst during the catalytic reaction. This is because rapid temperature changes can lead to the formation of a large number of crystal buds during the precursor formation process. These crystals, due to insufficient development, often grow small and are more likely to encapsulate impurities generated during the crystallization reaction. This makes the impurities difficult to remove during the subsequent washing and activation process, thus affecting the performance of the resulting catalyst.

[0344] Comparative Example 9

[0345] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0346] (2) Then, 0.1 g of the 1-11# catalyst prepared in Comparative Example 6 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and the temperature was programmed to 150°C for 2 h.

[0347] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 11.

[0348] Table 11 Reaction results of comparative example 9

[0349] Comparative Example BHMF yield HMF conversion Catalyst selectivity 9 21 52 40

[0350] Compared with Example 34, the catalyst sample used in Comparative Example 9 was changed from 1-1# to 1-11#, that is, the preparation method of the carrier was changed. No stabilizer was added during the preparation of the modified MOFs carrier, and the other preparation conditions remained unchanged. Since no stabilizer was added in the crystallization reaction, the carrier formed an irregular or unstable crystal structure during the molding process, and the dispersion and stability of the crystal were reduced, thereby affecting the selectivity of the catalyst for HMF and the yield of BHMF during the catalytic reaction.

[0351] Example 42

[0352] The 2-1# modified MOFs support (2.5 wt% Cu) prepared in Example 22 was selected for catalytic hydrogenation reaction, and the same reaction conditions as in Example 34 were adopted. After the reaction, the contents in the reaction solution were analyzed by LC. The results are shown in Table 12.

[0353] Example 43

[0354] The 3-1# modified MOFs support (7.5 wt% Cu) prepared in Example 23 was selected for catalytic hydrogenation reaction, and the same reaction conditions as in Example 34 were adopted. After the reaction, the contents in the reaction solution were analyzed by LC. The results are shown in Table 12.

[0355] Example 44

[0356] The 4-1# modified MOFs support (10 wt% Cu) prepared in Example 24 was selected for catalytic hydrogenation reaction, and the same reaction conditions as in Example 34 were adopted. After the reaction, the contents in the reaction solution were analyzed by LC. The results are shown in Table 12.

[0357] Example 45

[0358] The 5-1# modified MOFs support (5 wt% Ni) prepared in Example 25 was selected for catalytic hydrogenation reaction, and the same reaction conditions as in Example 34 were adopted. After the reaction, the contents in the reaction solution were analyzed by LC. The results are shown in Table 12.

[0359] Table 12 Reaction results

[0360] Example Load status BHMF yield HMF conversion Catalyst selectivity 34 Cu (5 wt%) 96 98 98 42 Cu (2.5 wt%) 86 90 95 43 Cu (7.5 wt%) 98 100 98 44 Cu (10 wt%) 93 100 93 45 Ni (5wt%) 86 91 94

[0361] Compared to Example 34, Examples 42, 43, and 44 used catalyst samples modified by varying the metal loading during the support loading process, while maintaining all other preparation conditions. The data in Table 12 show that a reduction in the metal loading significantly reduces the final BHMF yield. Excessive metal loading can lead to the formation of other byproducts during the reaction, further impacting the final BHMF yield. Therefore, the metal loading on the support influences both the BHMF yield and selectivity.

[0362] Compared to Example 34, Example 45 used a different catalyst sample, from 1-1# to 5-1#. Specifically, the metal loaded in the prepared supported catalyst was changed from Cu to Ni. All other preparation conditions remained unchanged, resulting in a significantly lower BHMF yield. This indicates that the difference in the metal loaded in the supported catalyst affects the BHMF yield in the final catalytic reaction.

[0363] Example 46

[0364] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0365] (2) 0.1 g of the 6-1# catalyst prepared in Example 26 was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C, and the hydrogenation reaction time was 2 h.

[0366] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 13.

[0367] Table 13 Reaction results of Example 46

[0368] Example BHMF yield HMF conversion Catalyst selectivity 46 65 81 80

[0369] Compared to Example 34, Example 46 used a different catalyst sample, from 1-1# to 6-1#. This was due to a change in the carrier preparation method. Specifically, during the preparation of the supported catalyst, the heating rate to the specified calcination temperature was increased from 1°C / min to 5°C / min. All other preparation conditions remained unchanged. However, the selectivity and yield of BHMF decreased significantly. This indicates that a rapid heating rate can cause agglomeration of the metal particles supported on the carrier, thereby affecting the catalyst selectivity and BHMF yield in the final catalytic reaction.

[0370] Example 47

[0371] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0372] (2) 0.1 g of the catalyst #7-1 prepared in Example 27 was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C, and the hydrogenation reaction time was 2 h.

[0373] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 14.

[0374] Table 14 Reaction results of Example 47

[0375]

[0376]

[0377] Compared with Example 34, Example 47, the catalyst sample used in this example has changed from 1-1# to 7-1#, that is, the preparation method of the carrier has changed, that is, in the process of preparing the supported catalyst, the specified calcination temperature has been changed from 300°C to 500°C, and the other preparation conditions have not changed. The final selectivity and yield of BHMF have decreased significantly. It can be seen that excessively high calcination temperature may burn the spatial structure of MOFs and affect the dispersion of the metal atom load, thereby affecting the selectivity of the catalyst and the yield of BHMF in the final catalytic reaction.

[0378] Example 48

[0379] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0380] (2) Then, 0.1 g of the 8-1# catalyst prepared in Example 28 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0381] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 15.

[0382] Table 15 Reaction results of Example 48

[0383] Example BHMF yield HMF conversion Catalyst selectivity 48 61 77 79

[0384] Compared with Example 34, Example 48, the catalyst sample used in this example has changed, and the catalyst sample used has changed from 1-1# to 8-1#, that is, the preparation method of the carrier has changed, that is, in the process of preparing the supported catalyst, the specified calcination temperature is changed from 300°C to 200°C, and the other preparation conditions are unchanged. The final selectivity and yield of BHMF have decreased significantly. It can be seen that insufficient calcination temperature will reduce the activity of the catalyst, resulting in a smaller specific surface area of ​​the catalyst, thereby limiting the contact area between the reactants and the catalyst, further reducing the catalytic efficiency, thereby affecting the selectivity of the catalyst and the yield of BHMF in the final catalytic reaction.

[0385] Example 49

[0386] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0387] (2) Then, 0.1 g of the 9-1# catalyst prepared in Example 29 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and the temperature was programmed to 150°C for 2 h.

[0388] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 16.

[0389] Table 16 Reaction results of Example 49

[0390] Example BHMF yield HMF conversion Catalyst selectivity 49 82 91 90

[0391] Compared with Example 34, Example 49 used a different catalyst sample from 1-1# to 9-1#, i.e., the carrier preparation method was changed. In the process of preparing the supported catalyst, the heating rate to the specified reduction temperature was changed during the hydrogen atmosphere reduction, from 1°C / min to 5°C / min. The other preparation conditions remained unchanged, and the final BHMF yield and selectivity decreased significantly. This shows that when reducing in a hydrogen atmosphere, a heating rate that is too fast will cause the metal particles on the carrier to agglomerate, thereby affecting the selectivity of the catalyst and the BHMF yield in the final catalytic reaction.

[0392] Example 50

[0393] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0394] (2) 0.1 g of the 10-1# catalyst prepared in Example 30 was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C, and the hydrogenation reaction time was 2 h.

[0395] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 17.

[0396] Table 17 Reaction results of Example 50

[0397] Example BHMF yield HMF conversion Catalyst selectivity 50 57 79 72

[0398] Compared with Example 34, Example 50 shows that the catalyst sample used in this example has changed from 1-1# to 10-1#, that is, the preparation method of the carrier has changed. In the process of preparing the supported catalyst, the specified reduction temperature was changed during the reduction under hydrogen atmosphere, and the specified reduction temperature was increased from 300°C to 600°C. The other preparation conditions remained unchanged. The final yield and selectivity of BHMF decreased significantly. It can be seen that excessively high reduction temperature will burn the spatial structure of MOFs and affect the dispersion of metal atom loading. At the same time, at excessively high temperatures, the skeleton of the MOFs carrier collapses, causing a large amount of agglomeration of the metal particles loaded on the carrier, thereby seriously affecting the selectivity of the catalyst and the yield of BHMF in the final catalytic reaction.

[0399] Example 51

[0400] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0401] (2) 0.1 g of the catalyst #11-1 prepared in Example 31 was then added, with the mass ratio of substrate HMF to catalyst being 5:1. The mixture was then transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C, and the hydrogenation reaction time was 2 h.

[0402] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 18.

[0403] Table 18 Reaction results of Example 51

[0404] Example BHMF yield HMF conversion Catalyst selectivity 51 64 86 74

[0405] Compared with Example 34, Example 51, the catalyst sample used in this example has changed, and the catalyst sample used has changed from 1-1# to 11-1#, that is, the preparation method of the carrier has changed, that is, in the process of preparing the supported catalyst, during the reduction in hydrogen atmosphere, the specified reduction temperature was changed from 300°C to 100°C, and the other preparation conditions were unchanged. The final yield and selectivity of BHMF have decreased significantly. It can be seen that insufficient reduction temperature will result in the incomplete reduction of the active components of the catalyst, thereby affecting the activity and efficiency of the catalyst.

[0406] Example 52

[0407] (1) Add 30 ml of isopropanol and 1 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 264 mM. Take a sample as the initial reaction concentration.

[0408] (2) Then, 0.1 g of the 1-1# catalyst prepared in Example 14 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 10:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0409] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 19.

[0410] Table 19 Reaction results of Example 52

[0411] Example BHMF yield HMF conversion Catalyst selectivity 52 81 88 92

[0412] Compared to Example 34, Example 52 used a different amount of HMF in the raw material. All other conditions remained unchanged. As the amount of HMF in the raw material increased, the HMF concentration in the reaction solution increased, but the final BHMF yield decreased. This suggests that increasing the raw material concentration in the system does not necessarily increase BHMF yield. Excess raw material is densely distributed in the reaction system, inhibiting catalyst activity, leading to a decrease in BHMF yield and a decline in catalyst selectivity.

[0413] Example 53

[0414] (1) Add 30 ml of isopropanol and 0.25 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 66 mM. Take a sample as the initial reaction concentration;

[0415] (2) Then, 0.1 g of the 1-1# catalyst prepared in Example 14 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 2.5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0416] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 20.

[0417] Table 20 Reaction results of Example 53

[0418] Example BHMF yield HMF conversion Catalyst selectivity 53 99 100 99

[0419] Compared to Example 34, Example 53 varied the mass of HMF in the raw materials used in this example. All other conditions remained unchanged. As the mass of HMF in the raw materials decreased, the HMF concentration in the reaction solution decreased, and the final BHMF yield increased. This indicates that reducing the raw material concentration in the system, while maintaining the mass of the catalyst, effectively reduces the ratio of raw material HMF to catalyst. The minimal amount of raw material significantly disperses the reaction system, effectively reducing the ratio of raw material HMF to catalyst, making it easier for the catalyst to interact with the raw materials and leading to an increase in yield. Therefore, an appropriate raw material HMF concentration and an optimal catalyst ratio are essential for optimal experimental efficiency.

[0420] Example 54

[0421] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0422] (2) Then, 0.1 g of the 1-1# catalyst prepared in Example 14 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 80°C and the hydrogenation reaction time was 2 h.

[0423] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 21.

[0424] Table 21 Reaction results of Example 54

[0425] Example BHMF yield HMF conversion Catalyst selectivity 54 65 87 75

[0426] In Example 54, compared to Example 34, the final constant reaction temperature was changed. All other conditions remained unchanged. As the final constant reaction temperature decreased, HMF conversion was incomplete, the catalyst selectivity was also weak, and the final BHMF yield decreased. This indicates that decreasing the temperature reduces catalyst activity, affecting HMF conversion and selectivity, and ultimately reducing BHMF yield. This demonstrates that an appropriate temperature can accelerate HMF conversion and improve BHMF yield.

[0427] Example 55

[0428] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0429] (2) 0.1 g of the catalyst #1-1 prepared in Example 14 was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 200°C, and the hydrogenation reaction time was 2 h.

[0430] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 22.

[0431] Table 22 Reaction results of Example 55

[0432] Example BHMF yield HMF conversion Catalyst selectivity 55 87 100 87

[0433] Compared to Example 34, Example 55 differs from Example 34 in that the final constant reaction temperature was changed. All other conditions remained unchanged. As the final constant reaction temperature increased, HMF conversion was essentially complete, but the final BHMF yield decreased. This is due to the high heat conditions, which caused some of the raw HMF to simultaneously migrate toward the product BHMF and polymerization. Similarly, BHMF, due to the excessively high temperature, also migrated toward side reactions such as polymerization, resulting in decreased catalyst selectivity and BHMF yield. This demonstrates that an appropriate temperature maintains the stability of both the raw HMF and the product BHMF, ensuring catalyst selectivity and BHMF yield in the final catalytic reaction.

[0434] Example 56

[0435] (1) Add 30 ml of isopropanol and 0.1 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 26.4 mM. Take a sample as the initial reaction concentration.

[0436] (2) Then, 0.1 g of the 1-1# catalyst prepared in Example 14 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 1:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0437] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 23.

[0438] Table 23 Reaction results of Example 56

[0439] Example BHMF yield HMF conversion Catalyst selectivity 56 97 99 98

[0440] In Example 56, compared with Example 34, the ratio of the substrate and the catalyst used in this example was changed, while the other conditions remained unchanged. As the ratio of the substrate and the catalyst used was reduced, the contact between the catalyst and the raw material was more sufficient, resulting in an increase in the yield and an increase in the catalyst selectivity, and the final BHMF yield increased.

[0441] Example 57

[0442] (1) Add 30 ml of isopropanol and 2.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 660 mM. Take a sample as the initial reaction concentration.

[0443] (2) 0.1 g of the catalyst #1-1 prepared in Example 14 was then added, with the mass ratio of substrate HMF to catalyst being 25:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C, and the hydrogenation reaction time was 2 h.

[0444] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 24.

[0445] Table 24 Reaction results of Example 57

[0446] Example BHMF yield HMF conversion Catalyst selectivity 57 80 87 92

[0447] In Example 57, compared to Example 34, the substrate-to-catalyst ratio was changed, while all other conditions remained unchanged. As the substrate-to-catalyst ratio increased, the catalyst content in the same system decreased significantly, resulting in incomplete conversion of HMF and intermediates during the reaction, ultimately leading to a severely insufficient BHMF yield. This demonstrates that an appropriate catalyst content to support the reaction is essential for producing BHMF.

[0448] Example 58

[0449] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0450] (2) 0.1 g of the catalyst 1-1# prepared in Example 14 was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C, and the hydrogenation reaction time was 4 h.

[0451] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 25.

[0452] Table 25 Reaction results of Example 58

[0453] Example BHMF yield HMF conversion Catalyst selectivity 58 98 100 98

[0454] Compared to Example 34, Example 58 differed in reaction time. All other conditions remained unchanged. The BHMF yield continued to increase with increasing reaction time. This demonstrates that the catalyst prepared according to the present invention exhibits strong tolerance for reaction time, exhibits specific selectivity for HMF, and exhibits no side reactions such as ring-opening with prolonged reaction time. While reaction time is essential for ensuring efficient HMF conversion and high BHMF yield, it is apparent that increasing reaction time does not significantly improve yield. Therefore, a suitable reaction time can be selected to balance experimental efficiency and industrial economics.

[0455] Example 59

[0456] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0457] (2) Then, 0.1 g of the 1-1# catalyst prepared in Example 14 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and the temperature was programmed to 150°C for 0.5 h.

[0458] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 26.

[0459] Table 26 Reaction results of Example 59

[0460] Example BHMF yield HMF conversion Catalyst selectivity 59 53 57 93

[0461] Compared with Example 34, the reaction time of Example 59 was changed, while the other conditions remained unchanged. As the reaction time was shortened, the conversion rate of HMF and the yield of BHMF were obviously insufficient. It can be seen that the reaction time is a necessary condition to ensure the efficient conversion of HMF and the yield of BHMF.

[0462] Example 60

[0463] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0464] (2) Then, 0.1 g of the 1-1# catalyst prepared in Example 14 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 4 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0465] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 27.

[0466] Table 27 Reaction results of Example 60

[0467] Example BHMF yield HMF conversion Catalyst selectivity 60 97 99 98

[0468] In Example 60, the reaction pressure was changed compared to Example 34, while all other conditions remained unchanged. As the pressure in the system increased, the conversion of HMF and the yield of BMHF both increased slightly. This indicates that pressure has an impact on the reaction, acting not only as a hydrogen supply condition but also as a factor influencing the catalytic hydrogenation reaction of the support.

[0469] Example 61

[0470] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0471] (2) Then, 0.1 g of the 1-1# catalyst prepared in Example 14 was added. At this time, the mass ratio of the substrate HMF to the catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 0.1 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The hydrogenation reaction temperature was 150°C and the hydrogenation reaction time was 2 h.

[0472] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 28.

[0473] Table 28 Reaction results of Example 61

[0474] Example BHMF yield HMF conversion Catalyst selectivity 61 64 72 89

[0475] In Example 61, the reaction pressure was changed compared to Example 34, while the other conditions remained unchanged. However, as the pressure in the system decreased, the HMF conversion and BMHF yield were significantly insufficient. This indicates that pressure has an impact on the reaction.

[0476] Example 62

[0477] Compared with Example 34, the difference between this example is that the hydrogen gas is 8 MPa, the temperature of the catalytic hydrogenation reaction is 100° C., and the time is 10 h.

[0478] Example 63

[0479] Compared with Example 34, this embodiment differs in that the mass ratio of 5-hydroxymethylfurfural to supported catalyst is 30:1.

[0480] Example 64

[0481] Catalyst recycling experiment

[0482] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0483] (2) 0.1 g of the catalyst 1-1# prepared in Example 14 was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the mixture was transferred to a hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 4 MPa, the rotation speed was adjusted to 800 rpm, and a temperature program was started. The reaction temperature was 150°C and the reaction time was 2 h.

[0484] (3) After the reaction is completed, the mixture is cooled to room temperature and the contents of the reaction solution of the first reaction are analyzed by LC.

[0485] (4) Filter out the catalyst, wash it three times with water, then wash it three times with isopropanol, put it into a polytetrafluoroethylene liner and seal it with 15ml of isopropanol (minimize the time of contact with air), then add 0.5g of HMF and 15ml of isopropanol solvent to the liner (maintain the amount of solvent in the system unchanged). At this time, the mass ratio of substrate HMF and catalyst is still 5:1, and it is transferred to the hydrogenation reactor. After three times of nitrogen replacement of air, hydrogen is introduced to 2Mpa, the speed is adjusted to 800rpm, and the temperature program is started. The reaction temperature is 150℃ and the reaction time is 2h;

[0486] (5) After the reaction is completed, the mixture is cooled to room temperature and the contents of the reaction solution of the second reaction are analyzed by LC.

[0487] (6) Repeat the steps (4)-(5) and recycle the catalyst for 5 times. The LC analysis results are shown in Table 29.

[0488] Table 29 Reaction results of Example 64 - LC analysis

[0489] Number of reactions BHMF yield HMF conversion Catalyst selectivity first 96 98 98 Second time 96 98 98 The third time 96 98 98 Fourth time 95 98 97 Fifth 92 98 94

[0490] This example evaluated the catalyst through a replication experiment. The data in Table 29 indicate that the selectivity remained largely unchanged over three consecutive reactions. A slight decrease in catalyst selectivity only occurred after the fourth reaction. This experiment demonstrates that the support prepared by the present invention exhibits excellent thermal resistance and chemical stability, maintains morphological stability during repeated use, and exhibits no loss of supported metal particles even after repeated cycles. Furthermore, the support exhibits strong specificity for catalytic hydrogenation of HMF to produce BHMF.

[0491] Example 65

[0492] Catalyst regeneration

[0493] (1) The catalyst temporarily stored after the five-time application reaction in Example 64 was washed three times with isopropanol, washed three times with water, and then placed in an oven at 100°C for 2 hours until completely dry. Finally, the sample was placed in a muffle furnace and calcined at a gradient temperature from room temperature to 300°C at a heating rate of 1°C / min. It was calcined at this specified temperature for 3 hours, cooled, and taken out to obtain the oxidized catalyst after removing the deposited impurities.

[0494] (2) Then, the catalyst was reduced by gradient temperature increase in a tubular furnace under hydrogen atmosphere, with the temperature rising at a rate of 1°C / min from room temperature to 300°C, and reduced at the specified temperature for 2 hours to obtain a regenerated supported catalyst, which was recorded as 1-1-1#.

[0495] Verification reaction of regenerated catalyst

[0496] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0497] (2) Then, 0.1 g of regenerated 1-1-1# catalyst was added. At this time, the mass ratio of substrate HMF to catalyst was still 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and the temperature was programmed to 150°C for 2 h.

[0498] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 30.

[0499] Table 30 Reaction results of Example 65

[0500] Example BHMF yield HMF conversion Catalyst selectivity 65 95 98 97

[0501] This example demonstrates that the decrease in BHMF yield during the continuous catalyst reuse reaction is due to the accumulation of impurities deposited on the catalyst during the multiple biomass reactions. Calcination and reduction remove the impurities deposited on the MOF support surface, restoring the catalyst's excellent hydrogenation catalytic performance. This demonstrates the catalyst's high reusability, the resistance of the loaded metal particles to loss and deactivation, and its excellent regeneration performance.

[0502] Comparative Example 10

[0503] Experimental verification of the reaction of unmodified MOFs carrier after metal loading and regeneration

[0504] (1) Add 30 ml of isopropanol and 0.5 g of HMF to a polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably distributed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration.

[0505] (2) Then, 0.1 g of the prepared 1-4# catalyst was added. At this time, the mass ratio of substrate HMF to catalyst was 5:1, and the mixture was transferred to the hydrogenation reactor. After three nitrogen replacements of air, hydrogen was introduced to 2 MPa, the rotation speed was adjusted to 800 rpm, and the temperature was programmed to 150°C for 2 h.

[0506] (3) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 31.

[0507] Catalyst regeneration

[0508] (4) After the reaction in step (3) is completed, the catalyst is regenerated using the same method as in Example 65.

[0509] Catalyst verification experiment after regeneration

[0510] (5) Add 30 ml of isopropanol and 0.5 g of HMF to the polytetrafluoroethylene liner and stir thoroughly to ensure that the raw materials are evenly dispersed and stably dispersed in the reaction system. At this point, the concentration of HMF in the solution system is 132 mM. Take a sample as the initial reaction concentration;

[0511] (6) The regenerated supported catalyst was then added, with the mass ratio of substrate HMF to catalyst being 5:1, and the catalyst was transferred to the hydrogenation reactor. After three nitrogen replacements of the air, hydrogen was introduced to 2 MPa, the speed was adjusted to 800 rpm, and a temperature program was started. The reaction temperature was 150°C and the reaction time was 2 h.

[0512] (7) After the reaction was completed, the mixture was cooled to room temperature and the contents of the reaction solution were analyzed by LC. The results are shown in Table 31.

[0513] Table 31 Reaction results of Example 66

[0514] Example 66 BHMF yield HMF conversion Catalyst selectivity Control reaction 80 86 93 After catalyst regeneration 62 75 83

[0515] In this example, no modifier was added to the support during the preparation of the 1-4# supported catalysts, and all other loading and reaction conditions remained unchanged. However, the BHMF yield achieved was significantly lower than that achieved in Example 64. Furthermore, compared to Example 65, the reaction data after catalyst regeneration indicate that the supported catalyst prepared in this example without support modification exhibited poor regeneration. Following high-temperature calcination and regeneration, the HMF conversion rate decreased, ultimately impacting the BHMF yield.

[0516] In addition, the inventors of this case also referred to the aforementioned embodiments and conducted experiments using other raw materials, process operations, and process conditions described in this specification, and obtained relatively ideal results.

[0517] It should be understood that the technical solution of the present invention is not limited to the above-mentioned specific implementation cases. Any technical variations made according to the technical solution of the present invention without departing from the scope of protection of the purpose of the present invention and the claims shall fall within the scope of protection of the present invention.

Claims

1. A method for preparing a modified MOFs carrier, characterized in that: include: A mixed reaction system comprising a carboxylate ligand, a zirconium salt, a stabilizer, a modifier and a first organic solvent is subjected to a dynamic crystallization reaction to obtain a modified MOFs precursor, which is then vacuum activated to obtain a modified MOFs carrier. The carboxylate ligand is selected from at least any one of terephthalic acid, trimesic acid, naphthalene dicarboxylic acid, and biphenyl-4,4-dicarboxylic acid; the stabilizer is selected from any one of acetic acid, citric acid, oxalic acid, ethylenediaminetetraacetic acid, and phosphoric acid, or a combination of two or more thereof; and the modifier is selected from any one of aluminum salts, tin salts, and silicates, or a combination of two or more thereof.

2. The preparation method according to claim 1, wherein: The zirconium salt includes an organic solvent-soluble zirconium salt; the zirconium salt includes any one of zirconium chloride, zirconium nitrate, and zirconium sulfate, or a combination of two or more thereof.

3. The preparation method according to claim 1, wherein: The molar ratio of zirconium ions contained in the zirconium salt to terephthalic acid is 1:0.1 to 1:

5.

4. The preparation method according to claim 1, wherein: The concentration of zirconium ions contained in the zirconium salt in the mixed reaction system is 0.1-100 mmol / L.

5. The preparation method according to claim 1, wherein: The volume of the stabilizer accounts for 0.01% to 15% of the total volume of the mixed reaction system.

6. The preparation method according to claim 1, wherein: The molar ratio of the modifier to terephthalic acid is 1:0.1 to 1:

20.

7. The preparation method according to claim 1, wherein: The first organic solvent includes any one of N,N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone, and acetone, or a combination of two or more thereof.

8. The preparation method according to claim 1, characterized in that The dynamic crystallization reaction includes: heating the mixed reaction system from room temperature to a specified crystallization reaction temperature at a heating rate of 0.5-10°C / min for a dynamic crystallization reaction; wherein the specified crystallization reaction temperature is 80-160°C, the dynamic crystallization reaction time is 6-96h, and the mechanical flip speed is 10-60rpm.

9. The preparation method according to claim 1, characterized in that The preparation method further includes: centrifuging the modified MOFs precursor obtained by the dynamic crystallization reaction, filtering, washing, and drying to obtain a dried modified MOFs precursor; wherein the centrifugation speed is 700-1200 rpm and the centrifugation time is 5-30 minutes; the washing includes first washing with DMF 3-5 times and then washing with acetone 3-5 times; the drying temperature is 60-80°C and the drying time is 6-12 hours.

10. The preparation method according to claim 1, characterized in that: The vacuum activation treatment is carried out under vacuum conditions, wherein the temperature of the vacuum activation treatment is 80-200° C., the time is 6-96 hours, and the activation vacuum degree is -0.01-0.1 MPa.

11. A modified MOFs carrier prepared by the preparation method according to any one of claims 1 to 10.

12. The modified MOFs carrier according to claim 11, characterized in that: The particle size of the modified MOFs carrier is 200nm~250nm, and the specific surface area is 1200~1300m 2 / g, the crystal form is octahedral.

13. A method for preparing a supported catalyst, characterized in that: include: Prepare a modified MOFs carrier according to the preparation method according to any one of claims 1 to 10; The metal elements are loaded on the modified MOFs carrier, and then calcined and reduced in sequence to obtain a loaded catalyst.

14. The preparation method according to claim 13, characterized in that: The metal element includes a transition metal element, and the transition metal element includes any one or a combination of two or more of Cu, Ni, Co, and Fe.

15. The preparation method according to claim 13, characterized in that The preparation method includes: fully immersing the modified MOFs carrier in a metal salt solution, so that the metal element is loaded on the modified MOFs carrier; the metal salt includes any one of transition metal element sulfate, transition metal element nitrate, transition metal element acetate, transition metal element phosphate, and transition metal element chloride, or a combination of two or more thereof.

16. The preparation method according to claim 13, characterized in that The preparation method comprises: gradually heating a modified MOFs carrier loaded with metal elements to a calcination temperature in an inert atmosphere, and performing the calcination treatment.

17. The preparation method according to claim 16, characterized in that: The inert atmosphere includes a nitrogen atmosphere.

18. The preparation method according to claim 13, characterized in that The preparation method comprises: heating the temperature from room temperature to a calcination temperature of 200-500° C. at a heating rate of 0.5-10° C. / min, and the calcination treatment time is 1 hour to 20 hours.

19. The preparation method according to claim 13, characterized in that The preparation method comprises: performing the reduction treatment on the calcined product in a reducing atmosphere.

20. The preparation method according to claim 19, characterized in that: The reducing atmosphere includes a hydrogen atmosphere.

21. The preparation method according to claim 13, characterized in that The preparation method comprises: heating from room temperature to a reduction temperature of 100-600° C. at a heating rate of 0.5-10° C. / min, and the reduction treatment time is 1 hour to 30 hours.

22. A supported catalyst prepared by the preparation method according to any one of claims 13 to 21, wherein the supported catalyst comprises a modified MOFs support and metal nanoparticles uniformly supported on the modified MOFs support.

23. The supported catalyst according to claim 22, characterized in that: The loading amount of the metal nanoparticles on the modified MOFs carrier is 0.1 wt% to 20 wt%.

24. Use of the supported catalyst according to claim 22 in the preparation of 2,5-furan dimethanol.

25. The use according to claim 24, characterized in that: The application includes the application of the supported catalyst in the preparation of 2,5-furan dimethanol by hydrogenation of 5-hydroxymethylfurfural.

26. A method for preparing 2,5-furan dimethanol, characterized in that: include: Providing the supported catalyst according to claim 22 or 23; Under hydrogen atmosphere and selected pressure conditions, 5-hydroxymethylfurfural is catalyzed by the supported catalyst to undergo catalytic hydrogenation reaction to prepare 2,5-furan dimethanol.

27. The preparation method according to claim 26, characterized in that include: mixing the supported catalyst, 5-hydroxymethylfurfural, and a second organic solvent to form a reaction solution; The concentration of 5-hydroxymethylfurfural in the reaction solution is 0.1-3000 mmol / L.

28. The preparation method according to claim 27, characterized in that: The second organic solvent includes any one of methanol, ethanol, n-propanol, isopropanol, and n-butanol, or a combination of two or more thereof.

29. The preparation method according to claim 26, characterized in that: The selected pressure condition refers to a pressure of 0.1 MPa to 8 MPa.

30. The preparation method according to claim 26, characterized in that: The temperature of the catalytic hydrogenation reaction is 80-200° C., and the time is 0.5-10 h.

31. The preparation method according to claim 26, characterized in that: The mass ratio of the 5-hydroxymethylfurfural to the supported catalyst is 1:1 to 30:1.

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