Acid-Ni catalyst for hydrogenation rearrangement reaction of 5-hydroxymethylfurfural, preparation method and application thereof

Abstract

The present invention belongs to the technical field of catalyst preparation, and provides an acid-Ni catalyst for the hydro-rearrangement reaction of 5-hydroxymethylfurfural, a preparation method thereof and an application thereof. The preparation method of the acid-Ni catalyst comprises the following process: first, a Ni multi-layered material NiM is prepared, where M is Al and / or Mg; then the Ni multi-layered material NiM is dispersed in an organic phosphonic acid solution, and a catalyst precursor PA / NiM is obtained through ligand self-assembly; then through thermal reduction treatment, an acid-Ni catalyst PA-Ni-M is obtained. This catalyst exhibits excellent catalytic activity and selectivity in the reaction of hydro-rearrangement of 5-hydroxymethylfurfural to 3-hydroxymethylcyclopentanone, and realizes the control of the hydrogenation reaction products of 5-hydroxymethylfurfural.

Description

Technical Field

[0001] The present invention belongs to the technical field of catalyst preparation, and particularly relates to an acid-Ni catalyst for the hydrogenation rearrangement reaction of 5-hydroxymethylfurfural, and a preparation method and application thereof. Background Art

[0002] 5-Hydroxymethylfurfural (HMF) contains multiple functional groups (furan ring, carbonyl group and hydroxyl group), and can be easily obtained in large quantities by hydrolysis / dehydration of cellulose and hemicellulose. It is an important raw material for the conversion of biomass platform molecules into high-value chemicals. One of the high-value strategies is to change its furan ring structure and hydrogenate and rearrange it to produce cyclopentanone compounds, which can be used as precursors for synthetic drugs, dye intermediates, agricultural chemicals, spices or fuel additives.

[0003] The existing cyclopentanone production process is prepared by decarboxylation cyclization of petroleum-based 1,6-hexanedioic acid under high temperature conditions (270-400 °C) via Ba(OH)2, and the yield is only 60-80%. In contrast to using petroleum-based raw materials, using bio-based raw materials such as furfural or HMF not only has a low carbon footprint and conforms to the development prospect, but also can undergo hydrogenation rearrangement reactions at lower reaction temperatures (140-180 °C) to obtain cyclopentanone and its derivative 3-hydroxymethylcyclopentanone (HCPN) respectively, which has received much attention in the academic and industrial fields in recent years.

[0004] The hydrorearrangement reaction of furfural and HMF requires coupling hydrogenation, ring-opening, and intramolecular aldol condensation steps in a hydrothermal environment. HMF, which has one more hydroxymethyl functional group than furfural, has higher reactivity and is more prone to side reactions in a hydrothermal environment, making catalyst design more challenging. In this system, metal-acid bifunctional catalysts are often used to couple the metal sites for activating H2 with the acid sites for catalyzing ring-opening and aldol condensation to improve the selectivity of the products. In addition, the structural design of the catalyst active sites also needs to avoid over-hydrogenation of reaction intermediates (such as the formation of tetrahydrofuran dimethanol), hydrodeoxygenation (such as the formation of 2,5-hexanedione), or polymerization to form oligomers. Traditional noble metal-acid support bifunctional catalysts are difficult to achieve ideal results in this system. For example, the journal article Chemical Communications. 2014, 50: 5633-5636 reported supported catalysts of noble metals Pt, Pd, Au, and Ru. Among them, the optimal Au / Nb2O5 had a maximum HCPN yield of only 86% under a high hydrogen pressure of 8 MPa. In recent years, the journal article ACS Catalysis. 2023, 13(20): 13205-13214 reported a PdZn intermetallic catalyst that generates H + ―H - , providing proton acid and hydrogenation active sites respectively, thus achieving an HCPN yield of up to 95.8%, reaching the highest level reported in the existing literature. However, the 5.4 wt% noble metal Pd content in the catalyst limits the possibility of its industrial application. In contrast, the journal article ChemSusChem. 2016, 9(5): 521-531 reported a 47 wt% Ni / Al2O3 metal acid catalyst that could achieve an HCPN yield of 81% at the same temperature. If the interface between the metal sites and the acidic sites can be further optimized, the catalytic activity and selectivity can be enhanced, and the advantages of low cost and easy availability of non-noble metals can be utilized, it is expected to promote the industrial application of this high-value utilization path of HMF.

[0005] In the prior art, an organic ligand self-assembly method disclosed in the journal literature Nature Catalysis, 2018, 1, 148-155 and patent CN117019139A can construct a bifunctional catalyst with a controllable acid-metal interface on a traditional supported metal catalyst. However, the reported method is only applicable to noble metals that are not easily adsorbed by P, such as Pt, Ru, etc. When applied to transition metal Ni, due to the strong coordination between Ni and P elements, and the supported Ni precursor needs to be treated by high-temperature reduction (>400 °C), not only will the metal active sites be covered, thereby reducing the catalytic activity, but also it is easy to form a nickel phosphide active phase, such as the journal literature Journal of Catalysis, 2023, 421, 117-133 and Applied Catalysis B: Environment and Energy. 2024, 359:124413, etc. Although nickel phosphide exhibits excellent catalytic activity in many fields, the highest HCPN yield in the current reports based on nickel phosphide is only 72%, which is obviously not conducive to the hydrorearrangement reaction of HMF. Therefore, it is still difficult to construct an acid-metal Ni catalyst to highly selectively catalyze the production of HCPN from HMF without losing catalytic activity.

[0006] Therefore, to overcome the related technical defects of the current formation of nickel phosphide between Ni and P and the low selectivity of the Ni-based catalyst for the hydrorearrangement of HMF, it is very necessary to develop and construct a preparation strategy for a novel acid-Ni catalyst for the hydrorearrangement of 5-hydroxymethylfurfural to 3-hydroxymethylcyclopentanone. Summary of the Invention

[0007] In view of this, the present invention provides an acid-Ni catalyst for the hydrorearrangement reaction of 5-hydroxymethylfurfural and a preparation method thereof. By self-assembling organic phosphonic acid on a Ni-based multi-layered material to construct an acid-Ni catalyst, it is possible to maintain the catalytic activity while significantly increasing the selectivity of the hydrorearrangement of HMF to 3-hydroxymethylcyclopentanone without forming nickel phosphide.

[0008] To achieve the above object, the technical solution of the present invention is as follows:

[0009] A preparation method of an acid-Ni catalyst for the hydrorearrangement reaction of 5-hydroxymethylfurfural to 3-hydroxymethylcyclopentanone, comprising the following steps:

[0010] (1) Prepare a precipitant with a certain concentration. Under the condition of constant-temperature stirring, add an appropriate amount of nickel salt aqueous solution and aluminum salt aqueous solution, with or without adding magnesium salt aqueous solution, and maintain the pH of the reaction system at 10 ± 1. Subsequently, after aging, filtering, washing, and heat treatment, grind to obtain the Ni multi-layered material NiM, where M is selected from Mg and / or Al;

[0011] (2) Disperse the Ni multi-layered material NiM in an organic phosphonic acid solution, and obtain a catalyst precursor PA / NiM through ligand self-assembly;

[0012] (3) Subject the catalyst precursor PA / NiM to thermal reduction treatment to obtain an acid-Ni catalyst PA-Ni-M;

[0013] Among them, in step (1), the molar ratio of Ni to Al ions is 1:(5 - 22); when a magnesium salt solution is added, the molar ratio of the sum of Ni and Mg ions to Al ions is (0.5 - 4):1;

[0014] In step (2), the mass ratio of the Ni multi-layered material NiM to the organic phosphonic acid NiM / PAs is 3 - 8; the self-assembly includes the following process: stir the mixed solution after dispersing the Ni multi-layered material NiM in the organic phosphonic acid solution at room temperature for 16 - 24 h, then perform heat treatment under flowing air at 100 - 160 °C for 4 - 8 h, wash, and dry to obtain the catalyst precursor PA / NiM.

[0015] The present invention is further configured such that in step (1), the precipitant is selected from one of sodium carbonate aqueous solution, ammonia water, or ammonium carbonate aqueous solution, the temperature of constant-temperature stirring is 45 - 85 °C, and the stirring rate is controlled at 400 - 800 r / min. Preferably, the precipitant is selected as sodium carbonate aqueous solution with a concentration of 0.1 M - 1.0 M.

[0016] The present invention is further configured such that in step (1), the pH value of the reaction system is adjusted with a sodium hydroxide solution, the concentration of the sodium hydroxide solution is 0.5 - 3.0 M, and the dropping rate of the sodium hydroxide solution is 1.0 - 2.0 mL / min.

[0017] The present invention is further configured such that in step (1), when a magnesium salt solution is added, the molar ratio of the sum of Ni and Mg ions to Al ions is (1 - 3):1, such as 1:1, 2:1, or 3:1.

[0018] The present invention is further configured such that in step (1), the total molar concentration of the metal salt water is 0.4 - 2.0 M. The value of the total molar concentration of the metal salt water is the ratio of the sum of the molar amounts of the nickel salt, aluminum salt, and magnesium salt to the total volume of the system.

[0019] The present invention is further configured such that the nickel salt, aluminum salt, and magnesium salt are all nitrates.

[0020] The present invention is further configured such that in step (1), the specific processes of aging, filtration, washing, and heat treatment are as follows: continuously stir at 45 - 85 °C for 12 - 24 h, then filter and wash with ultrapure water until neutral, and then perform heat treatment at 160 - 220 °C for 6 - 8 h.

[0021] The present invention is further configured such that in step (2), the organic phosphonic acid is selected from one or more of methylphosphonic acid (MPA), dimethylphosphonic acid (DMPA), butylphosphonic acid (BPA), or benzylphosphonic acid (BZPA).

[0022] The present invention is further configured such that in step (2), the concentration of the organic phosphonic acid solution is 1.5 - 3.0 g / L; preferably 1.5 - 2.0 g / L.

[0023] The present invention is further configured such that in step (2), the mass ratio of the multi - layer material NiM to the organic phosphonic acid NiM / PAs is 4 - 8, for example, the mass ratio is 4, 5, 6, 7, or 8.

[0024] The present invention is further configured such that during the self - assembly process, the drying conditions are: vacuum drying at 60 - 90 °C for 1 - 6 h, preferably at 70 - 80 °C for 2 - 3 h.

[0025] Through the self - assembly process, the organic phosphonic acid is effectively modified on the surface of the multi - layer material, so that the organic phosphonic acid does not fall off during subsequent centrifugal separation, heat treatment, or thermal reduction processes.

[0026] The present invention is further configured such that in step (3), the thermal reduction temperature is 400 - 600 °C, the residence time at the reduction temperature is 1 - 4 h; the heating rate is 2 - 5 °C / min, the atmosphere is a H2 / Ar mixed gas, and the gas flow rate is controlled at 50 - 200 mL / min.

[0027] The present invention provides an acid - Ni catalyst prepared by the above - described preparation method. The "acid" in the acid - Ni catalyst refers to the Brønsted acid site that provides protonic acid during the reaction, and acid - Ni represents the acid - Ni interface site constructed by this catalyst.

[0028] The present invention is further configured such that in the acid - Ni catalyst, the Ni content is 4 - 10 wt%.

[0029] The present invention also provides an application of the above - described acid - Ni catalyst in the reaction of hydrogenation and rearrangement of 5 - hydroxymethylfurfural to 3 - hydroxymethylcyclopentanone.

[0030] The present invention is further configured such that the reaction conditions for the hydrogenation and rearrangement of 5-hydroxymethylfurfural to 3-hydroxymethylcyclopentanone are as follows: temperature 120-150 °C, hydrogen pressure 2.0-4.0 MPa.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] (1) The technical solution of the present invention avoids the strong adsorption of phosphorus on metallic Ni, which inhibits the hydrogen evolution ability of metallic Ni, and also avoids the formation of nickel-phosphorus compounds with uncertain active components, by self-assembling organic phosphonic acid in the multi-layered metal material precursor, thereby improving the selectivity of the catalyst for the hydrogenation and rearrangement of 5-hydroxymethylfurfural to 3-hydroxymethylcyclopentanone.

[0033] (2) In the preparation method of the Ni catalyst of the present invention, the alkyl end of the organic phosphonic acid adjusts the molecular layer density of the organic phosphonic acid molecular layer on the catalyst surface through steric hindrance, and then different densities of acid-metal Ni interfacial sites can be precisely constructed, thereby regulating the ratio between the full hydrogenation and the hydrogenation rearrangement reactions, and realizing the control of the hydrogenation reaction products of 5-hydroxymethylfurfural.

[0034] (3) The acid-Ni catalyst provided by the present invention is applicable to multi-layered metal materials with different compositions, providing a new idea for other reaction systems of non-precious metals and acid-metal bifunctional catalysis. Description of the Drawings

[0035] Figure 1 Shows the X-ray diffraction patterns of the acid-Ni catalysts prepared in Examples 1-4 and the Ni catalyst prepared in Comparative Example 1. Among them, Al2O3: PDF #10-0425 is the Al2O3 standard card corresponding to this group of spectra; Ni: PDF #04-0850 is the Ni standard card corresponding to this group of spectra.

[0036] Figure 2 Shows the transmission electron micrographs and particle size distributions of the acid-Ni catalysts prepared in Examples 1-4 and the Ni catalyst prepared in Comparative Example 1; among them, (a) is the Ni catalyst prepared in Comparative Example 1, and (b)-(e) are the acid-Ni catalysts prepared in Examples 1, 2, 3, and 4 in sequence.

[0037] Figure 3 Shows the infrared spectra of the acid-Ni catalysts prepared in Examples 1-4 and the Ni catalyst prepared in Comparative Example 1.

[0038] Figure 4 Shows the NH3-TPD diagrams of the acid-Ni catalysts prepared in Examples 1, 3, and 4 and the Ni catalyst prepared in Comparative Example 1.

[0039] Figure 5The EXAFS diagrams of the acid-Ni catalysts prepared in Examples 1, 3, and 4, the Ni catalyst prepared in Comparative Example 1, and the Ni standard wafer are shown.

[0040] Figure 6 The X-ray diffraction patterns of the catalyst precursor materials prepared in step (2) of Examples 1 and 5 and the precursor material prepared in Comparative Example 1 are shown; among them, JCPDS#22-0700 is the standard card for the multi-layered material.

[0041] Figure 7 The X-ray diffraction patterns of the acid-Ni catalysts prepared in Examples 5 and 9 and the Ni catalysts prepared in Comparative Examples 2 and 3 are shown; among them, Mg2O: PDF#65-0476 is the Mg2O standard card corresponding to this group of patterns; Ni: PDF #04-0850 is the Ni standard card corresponding to this group of patterns. Detailed implementation manners

[0042] The present invention will be described in detail and completely below with specific examples in conjunction with the accompanying drawings. It should be understood that the described embodiments are only part of the embodiments of the present invention, rather than all embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of the present invention. Example 1

[0043] To prepare the MPA-5Ni-Al catalyst, the following steps are included:

[0044] (1) After completely dissolving 1.018 g of nickel nitrate hexahydrate and 28.697 g of aluminum nitrate nonahydrate in 100 mL of ultrapure water, it was gradually added dropwise at a rate of 0.8 mL / min to a flask containing 100 mL of 0.4 mol / L Na2CO3 aqueous solution, the temperature was maintained at 65 °C, and the pH value was adjusted to be within the range of 10.0 ± 0.1 by 1.2 mol / L NaOH aqueous solution; during the dropping process, a magnetic stirrer was continuously used to ensure uniform mixing; after the dropping was completed, it was continuously stirred in an environment of 65 °C for 16 h, then filtered, the precipitate was washed to neutrality, and then placed in an oven at 220 °C for heat treatment for 8 h, ground to be uniform, and the obtained multi-layered material NiAl was collected.

[0045] (2) Completely dissolve 250 mg of MPA (methylphosphonic acid, purity ≥ 99%) in 125 mL of THF, then add 1 g of the multi-layered material NiAl obtained in step (1), continuously stir at room temperature for 16 h, then separate by centrifugation, place the remaining solid in a flowing air environment at 160 °C for heat treatment for 6 h; finally, filter and wash the solid powder obtained by heat treatment with 500 mL of THF, place it in a vacuum drying oven at 80 °C for drying for 2 h, grind it until uniform, and collect the obtained catalyst precursor MPA / NiAl.

[0046] (3) Place the catalyst precursor MPA / NiAl obtained in step (2) in a tubular furnace, raise the temperature to 450 °C at a rate of 3 °C / min in a 10 vol % H2 / Ar atmosphere and keep it constant for 4 h, then switch to inert gas purge and naturally cool to room temperature to obtain an acid-Ni catalyst MPA-5Ni-Al containing 5 wt% Ni.

[0047] Characterize the MPA-5Ni-Al catalyst prepared in this example. Among them, the X-ray diffraction pattern is as Figure 1 shown; the transmission electron microscope image and particle size distribution of the catalyst are as Figure 2 shown. It can be seen from Figure 2 that the Ni particles in the catalyst are evenly dispersed, and the average particle size is 5.5 nm; the infrared spectrum is as Figure 3 shown. The MPA-5Ni-Al catalyst shows characteristic peaks of C-H stretching vibration around 2920 - 2930 cm -1 , proving the effective modification of methylphosphonic acid; the NH3-TPD pattern is as Figure 4 shown. Compared with Comparative Example 1, its total acid amount is reduced; the EXAFS pattern is as Figure 5 shown, showing the presence of Ni-Ni bonds and no Ni-P bonds; the X-ray diffraction pattern of the catalyst precursor material MPA / NiAl obtained in step (2) is as Figure 7 shown. Example 2

[0048] Prepare the DMPA-5Ni-Al catalyst. Its preparation steps are basically the same as those in Example 1, except that the organic phosphonic acid MPA in Example 1 is replaced by DMPA.

[0049] Characterize the DMPA-5Ni-Al catalyst prepared in this example. Among them, the X-ray diffraction pattern is as Figure 1 shown, which is basically the same as the MPA-5Ni-Al catalyst prepared in Example 1; the transmission electron microscope image and particle size distribution of the catalyst are as Figure 2 shown. It can be seen from Figure 2It can be seen that the Ni particles in the catalyst are uniformly dispersed, with an average particle size of 5.4 nm. Its morphology and average particle size are basically the same as those in Example 1; the infrared spectrogram is as Figure 3 shown. For the DMPA-5Ni-Al catalyst, characteristic peaks of C-H stretching vibration also appear at around 2920 - 2930 cm -1 , proving the effective modification of dimethylphosphonic acid. Example 3

[0050] Prepare the BPA-5Ni-Al catalyst. Its preparation steps are basically the same as those in Example 1, except that the organic phosphonic acid MPA in Example 1 is replaced by BPA.

[0051] Characterize the BPA-5Ni-Al catalyst prepared in this example. Among them, the X-ray diffraction pattern is as Figure 1 shown, which is basically the same as the MPA-5Ni-Al catalyst prepared in Example 1; the transmission electron micrograph and particle size distribution of the catalyst are as Figure 2 shown. It can be seen from Figure 2 that the Ni particles in the catalyst are uniformly dispersed, with an average particle size of 5.0 nm. Its morphology and average particle size are basically the same as those in Example 1; the infrared spectrogram is as Figure 3 shown. For the DMPA-5Ni-Al catalyst, characteristic peaks of C-H stretching vibration appear at around 2910 - 2940 cm -1 , proving the effective modification of butylphosphonic acid; the NH3-TPD pattern is as Figure 4 shown. Compared with the MPA-modified MPA-5Ni-Al catalyst (Example 1), its total acid amount has increased. The EXAFS pattern is as Figure 5 shown, which also shows the presence of Ni-Ni bonds and no Ni-P bonds, indicating that by using the preparation method described in the present invention, replacing different organic phosphonic acids will not generate nickel phosphide compounds either. Example 4

[0052] Prepare the BZPA-5Ni-Al catalyst. Its preparation steps are basically the same as those in Example 1, except that: the organic phosphonic acid MPA in Example 1 is replaced by BZPA (benzylphosphonic acid, purity ≥ 99.97%).

[0053] Characterize the BZPA-5Ni-Al catalyst prepared in this example. Among them, the X-ray diffraction pattern is as Figure 1 shown, which is basically the same as the MPA-5Ni-Al catalyst prepared in Example 1; the transmission electron micrograph and particle size distribution of the catalyst are as Figure 2 shown. It can be seen from Figure 2 that the Ni particles in the catalyst are uniformly dispersed, with an average particle size of 4.4 nm. Its morphology and average particle size are basically the same as those in Example 1; the infrared spectrogram is as Figure 3As shown, the BZPA-5Ni-Al catalyst exhibits characteristic stretching vibration peaks of aromatic hydrocarbons around 3000 - 3100 cm -1 , demonstrating the effective modification of benzylphosphonic acid; the NH3-TPD graph is as shown in Figure 4 . Compared with the BPA-modified BPA-5Ni-Al catalyst (Example 3), the number of its acid sites is further reduced. The EXAFS graph is as shown in Figure 5 . There is a Ni-Ni bond but no Ni-P bond, once again proving that in the preparation method described in the invention, changing different organic phosphonic acids will not generate nickel phosphide compounds. Example 5

[0054] Prepare the MPA-5Ni-MgAl-3 catalyst. Its preparation steps are basically the same as those in Example 1, except that: in step (1), magnesium nitrate hexahydrate is also added. Specifically:

[0055] Completely dissolve 0.8607 g of nickel nitrate hexahydrate, 7.503 g of aluminum nitrate nonahydrate, and 14.626 g of magnesium nitrate hexahydrate in 100 ml of ultrapure water, and then gradually add it dropwise into a flask containing 100 mL of 0.4 mol / L Na2CO3 aqueous solution at a flow rate of 0.8 mL / min. The temperature is maintained at 65 °C, and the pH value is adjusted to be within the range of 10.0 ± 0.1 by 1.2 mol / L NaOH aqueous solution; during the dropping process, a magnetic stirrer is continuously used to ensure uniform mixing; after the dropping is completed, continue to stir in an environment of 65 °C for 16 h, filter, then wash the precipitate to neutrality and place it in an oven at 220 °C for drying for 8 h, and grind it to uniformity to collect the obtained material NiMgAl.

[0056] Characterize the catalyst precursor material prepared in step (2) of this example and the MPA-5Ni-MgAl-3 catalyst obtained in this example. Among them, the X-ray diffraction pattern of the catalyst precursor material MPA / NiMgAl-3 obtained in step (2) is as shown in Figure 6 . It is similar in structure to Comparative Example 1 and Example 1, and both belong to multi-layered metal materials; the X-ray diffraction pattern of MPA-Ni-MgAl-3 is as shown in Figure 7 . It is similar in structure to Comparative Example 2. Example 6

[0057] Prepare the DMPA-5Ni-MgAl-3 catalyst. Its preparation steps are basically the same as those in Example 5, except that the organic phosphonic acid MPA in Example 5 is replaced with DMPA. Example 7

[0058] Prepare the BPA-5Ni-MgAl-3 catalyst. Its preparation steps are basically the same as those in Example 5, with the only difference being that the organic phosphonic acid MPA in Example 5 is replaced by BPA. Example 8

[0059] Prepare the BZPA-5Ni-MgAl-3 catalyst. Its preparation steps are basically the same as those in Example 5, with the only difference being that the organic phosphonic acid MPA in Example 5 is replaced by BZPA. Example 9

[0060] Prepare the MPA-5Ni-MgAl-1 catalyst. Its preparation steps are basically the same as those in Example 5, with the only differences being: the addition amounts of nickel nitrate hexahydrate, aluminum nitrate nonahydrate, and magnesium nitrate hexahydrate in step (1) are different. In this example, 0.9305 g of nickel nitrate hexahydrate, 15.005 g of aluminum nitrate nonahydrate, and 9.436 g of magnesium nitrate hexahydrate are added in step (1).

[0061] The MPA-5Ni-MgAl-1 catalyst obtained in this example is characterized. The X-ray diffraction pattern thereof is as Figure 7 shown, and is similar to the structure of Comparative Example 3. Example 10

[0062] Prepare the DMPA-5Ni-MgAl-1 catalyst. Its preparation steps are basically the same as those in Example 9, with the only difference being that the organic phosphonic acid MPA in Example 5 is replaced by DMPA. Example 11

[0063] Prepare the BPA-5Ni-MgAl-1 catalyst. Its preparation steps are basically the same as those in Example 9, with the only difference being that the organic phosphonic acid MPA in Example 5 is replaced by BPA. Example 12

[0064] Prepare the BZPA-5Ni-MgAl-1 catalyst. Its preparation steps are basically the same as those in Example 9, with the only difference being that the organic phosphonic acid MPA in Example 5 is replaced by BZPA.

[0065] Comparative Example 1

[0066] Prepare the 5Ni-Al catalyst, including the following steps:

[0067] (1) 1.018 g of nickel nitrate hexahydrate and 28.697 g of aluminum nitrate nonahydrate were completely dissolved in 100 mL of ultrapure water, and then gradually added dropwise into a flask containing 100 mL of 0.4 mol / L aqueous sodium carbonate solution at a flow rate of 0.8 mL / min. The temperature was maintained at 65 °C, and the pH value was adjusted to be within the range of 10.0 ± 0.1 by 1.2 mol / L aqueous sodium hydroxide solution. During the dropping process, a magnetic stirrer was continuously used to ensure uniform mixing. After the dropping was completed, the mixture was continuously stirred at 65 °C for 16 h, and then the precipitate was washed to neutrality by filtration and placed in an oven at 220 °C for drying for 8 h, and then ground to uniformity to collect the obtained material NiAl.

[0068] (2) The material NiAl obtained in step (1) was placed in a tubular furnace, heated to 450 °C at a rate of 3 °C / min in a 10% H2 / Ar atmosphere and held for 4 h, and then switched to an inert gas purge and naturally cooled to room temperature to obtain a 5Ni-Al catalyst containing 5 wt% metallic Ni.

[0069] The 5Ni-Al catalyst prepared in this comparative example was characterized. Among them, the X-ray diffraction pattern was as Figure 1 shown, which was basically the same as the MPA-5Ni-Al catalyst prepared in Example 1; the transmission electron microscope image and particle size distribution of the catalyst were as Figure 2 shown. It could be seen from Figure 2 that the average particle size was 5.8 nm, and its morphology and average particle size were basically the same as those in Example 1; the infrared spectrum was as Figure 3 shown. Compared with Example 1, no characteristic peak of C-H stretching vibration appeared around 2910 - 2940 cm -1 ; the NH3-TPD pattern was as Figure 4 shown. Compared with this comparative example, the catalyst had more weak acid sites. The Fourier transform k2-weighted EXAFS pattern was as Figure 5 shown.

[0070] Comparative Example 2

[0071] Preparation of 5Ni-MgAl-3 catalyst

[0072] The preparation steps of this comparative example were basically the same as those of Comparative Example 1, except that: in step (1), the addition amounts of metal salts were changed to: 0.8607 g of nickel nitrate hexahydrate, 7.503 g of aluminum nitrate nonahydrate, and 14.626 g of magnesium nitrate hexahydrate.

[0073] The 5Ni-MgAl-3 catalyst prepared in this comparative example was characterized. Among them, the X-ray diffraction pattern was as Figure 7 shown.

[0074] Comparative Example 3

[0075] Prepare 5Ni-MgAl-1 catalyst

[0076] The preparation steps of this comparative example are basically the same as those of Comparative Example 1, except that: in step (1), the addition amounts of metal salts are changed to: nickel nitrate hexahydrate 0.9305 g, aluminum nitrate nonahydrate 15.005 g, and magnesium nitrate hexahydrate 9.436 g.

[0077] Characterize the 5Ni-MgAl-1 catalyst prepared in this comparative example. Among them, the X-ray diffraction pattern is as Figure 7 shown.

[0078] Comparative Example 4

[0079] Prepare 5Ni / Al2O3 catalyst, including the following steps:

[0080] (1) Prepare a 0.45 mol / L nickel nitrate ethanol solution, and quickly drop it into a small glass bottle containing 1 g of Al2O3 support. Then place the glass bottle on an oscillator and shake it quickly for 30 min, let it stand at room temperature for 16 h, then place it in an oven at 120 °C for heat treatment for 8 h, and take out the solid and grind it to obtain the catalyst precursor.

[0081] (2) Place the catalyst precursor obtained in step (1) in a tubular furnace, raise the temperature to 450 °C at a rate of 3 °C / min in a 10% H2 / Ar atmosphere and keep it constant for 4 h, then switch to an inert gas purge and cool it naturally to room temperature to obtain a 5Ni / Al2O3 catalyst containing 5 wt% Ni.

[0082] Comparative Example 5

[0083] Prepare MPA / 5Ni / Al2O3 catalyst, including the following steps:

[0084] (1) Prepare a 0.45 mol / L nickel nitrate ethanol solution, and quickly drop it into a small glass bottle containing 1 g of Al2O3 support. Then place the glass bottle on an oscillator and shake it quickly for 30 min, let it stand at room temperature for 16 h, then place it in an oven at 120 °C for heat treatment for 8 h, and take out the solid and grind it to obtain the catalyst precursor.

[0085] (2) Completely dissolve 250 mg of MPA in 125 mL of THF, then add 1 g of the catalyst precursor obtained in step (1), continuously stir at room temperature for 16 h, then perform centrifugal separation, and heat-treat the remaining solid in a flowing air environment at 160 °C for 6 h; finally, filter and wash the solid powder obtained by heat treatment with 500 mL of THF, place it in a vacuum drying oven at 80 °C for drying for 2 h, grind it until uniform, and collect the obtained precursor material.

[0086] (3) Place the precursor material obtained in step (2) in a tube furnace, heat it to 450 °C at a rate of 3 °C / min in a 10% H2 / Ar atmosphere and hold for 4 h, then switch to inert gas purge and naturally cool to room temperature to obtain an MPA-modified MPA / 5Ni / Al2O3 catalyst containing 5 wt% Ni.

[0087] Comparative Example 6

[0088] Preparation of MPA-5Ni-Al: 20 catalyst

[0089] The preparation steps of this comparative example are basically the same as those of Example 1, except that the addition amount of MPA in step (2) of Example 1 is different. The addition amount of MPA in this example is 0.05 g.

[0090] Comparative Example 7

[0091] Preparation of MPA-5Ni-Al: 1 catalyst

[0092] The preparation steps of this comparative example are basically the same as those of Example 1, except that the addition amount of MPA in step (2) of Example 1 is different. The addition amount of MPA in this example is 1 g. Example 13

[0093] Performance evaluation of the catalyst in the reaction of hydrogenation and rearrangement of HMF to HCPN

[0094] The organophosphonic acid-Ni catalysts prepared in Examples 1 to 12 and the Ni catalysts prepared in Comparative Examples 1 to 5 were used for the evaluation of the hydrogenation and rearrangement reaction of HMF at different temperatures and hydrogen pressures; the performance evaluation of the hydrogenation and rearrangement reaction of 5-hydroxymethylfurfural was carried out on a YZPR-650 reactor of Shanghai Yanzheng Instrument Co., Ltd. After the reaction, the reactor body was placed in an ice-water bath to quickly quench and stop the reaction, the reaction liquid was collected, then N,N-dimethylformamide was added as an internal standard, and finally 1.5 ml of the reaction liquid was sucked with a syringe and transferred into a gas chromatography vial through a 0.22 μm nylon filter membrane for waiting analysis.

[0095] The reactant and product distributions were quantitatively analyzed for the hydro-rearrangement reaction products of HMF using an Agilent 8860 gas chromatograph equipped with a DB-WAX UI capillary column (30 m in length, 0.32 mm in inner diameter, and 0.25 μm in film thickness) and an FID (Flame Ionization Detector).

[0096] Evaluation conditions: Before each catalyst evaluation, 20 mg of the catalyst not exposed to air was sealed in an aqueous solution in a tube furnace and completely transferred to the reaction kettle to prevent the catalyst from being oxidized during the extraction process. Subsequently, 10 mL of aqueous solution and 30 - 80 mg of the reactant (HMF) were loaded into the kettle. After loading, the gas in the kettle was replaced with argon three times to remove the original air in the kettle, and then the reaction kettle was heated to the required temperature (120 - 140 °C). When the reaction kettle reached the set temperature, the argon in the kettle was replaced with hydrogen five times and finally the hydrogen pressure was controlled at the required value (2 - 4 MPa). Subsequently, the stirring was started to initiate the reaction, and the stirring rate was 900 r / min.

[0097] The catalytic performance of the catalysts of the present invention for the hydro-rearrangement of HMF to HCPN was evaluated by testing the HMF conversion and HCPN selectivity of the organophosphonic acid-Ni catalysts prepared in Examples 1 - 12 and the Ni catalysts prepared in Comparative Examples 1 - 7, where:

[0098]

[0099] The results are shown in Table 1.

[0100] Table 1 Evaluation results of the organophosphoric acid-Ni catalyst PAs-5Ni-Al in the hydro-rearrangement HMF system

[0101]

[0102] As can be seen from the data in Table 1: In this example, the reaction of hydrogenation rearrangement of 5-hydroxymethylfurfural to 3-hydroxymethylcyclopentanone was selected to investigate Ni-based catalysts without phosphonic acid modification (Comparative Examples 1-7) and Ni-based catalysts modified with different organic phosphonic acids (Examples 1-12). After the reaction of Comparative Example 1 (5Ni-Al) and Examples 1-4 (MPA-5Ni-Al, DMPA-5Ni-Al, BPA-5Ni-Al, and BZPA-5Ni-Al) at 120 °C and 4 MPa in the aqueous phase for 4 h, both the conversion rate and selectivity were not ideal. This is because at this time, the reaction temperature was low, and most of the reacted HMF remained in the intermediate products, such as furan dimethanol BHF, etc. When the reaction time was extended and the reaction depth was further increased, it could be seen that the selectivity of HCPN in Examples 1 and 2 modified with organic phosphonic acids both increased. On the contrary, in Comparative Example 1, the unmodified 5Ni-Al tended to produce the phantom hydrogenation product BHTF. As the reaction temperature and hydrogen pressure increased, the conversion rates of all catalysts increased, and the selectivity also changed. As the temperature increased, the selectivity of HCPN on the comparative example (5Ni-Al) increased more than that of BHTF. As the hydrogen pressure increased, the reaction proceeded in the direction of BHTF. This is because the hydrogenation rearrangement reaction of HMF usually requires a higher activation energy than complete hydrogenation. Increasing the temperature is more favorable for hydrogenation rearrangement thermodynamically. Secondly, a large amount of H2 is required for the complete hydrogenation of HMF. Increasing the hydrogen pressure is beneficial to the increase in the concentration of H in the solution and promotes the complete hydrogenation reaction.

[0103] Generally speaking, in Comparative Example 1 without acid modification, the reaction did not mainly tend to the hydrogenation rearrangement reaction, and a large amount of BHTF by-products were still generated. In contrast, all of Examples 1-4 were more inclined to hydrogenation rearrangement to generate HCPN under the same conditions, and the selectivity of HCPN was increased by up to 1.8 times at most. It should be noted that for the catalyst modified with the strong steric hindrance group BZPA (Example 4), since there are more macromolecules on the surface of the carrier, a repulsive force is formed between the reactant molecules, reducing the diffusion rate of the reactant HMF from the solution to the surface of the carrier. Therefore, the conversion rate decreased slightly. Secondly, Examples 1 and 2 modified with MPA and DMPA had the highest HCPN selectivity, and Examples 3 and 4 modified with BPA and BZPA were the second. This is because the former two had the smallest steric hindrance and thus the highest density of acid-metal Ni interfaces, which was beneficial to the ring-opening rearrangement of the reaction intermediate BHF to generate HCPN. It should be noted that if a traditional impregnated Ni-based catalyst (Comparative Example 4, Ni / Al2O3) and an impregnated Ni-based catalyst modified with MPA (Comparative Example 5, MPA / Ni / Al2O3) were used, the organic phosphonic acid would directly adsorb on the metal Ni and shield the reaction active sites. As shown by the reaction results of Comparative Example 5 under the same conditions, the conversion rate was only 34.8%.

[0104] In addition, according to the above experimental results, it can be seen that the metal of the Ni-based multi-layered material is replaced, and Mg ions are introduced to form a NiMgAl ternary layered material. With the introduction of Mg, the Lewis acid sites on the surface of the alumina support are neutralized, the ring-opening rearrangement reaction is inhibited, and the selectivity of BHTF is as high as 99%. Similar to the previous results, HMF is more inclined to generate HCPN on PAs-5Ni-MgAl modified by organic phosphonic acid.

[0105] The above results indicate that the organic phosphonic acid-Ni catalyst has good catalytic activity for the hydrogenation rearrangement of 5-hydroxymethylfurfural to 3-hydroxymethylcyclopentanone, providing a good way for the high-value utilization of the biomass platform molecule 5-hydroxymethylfurfural. Example 14

[0106] Initial reaction kinetics of the organic phosphonic acid-Ni catalyst in the hydrogenation rearrangement reaction of BHF to HCPN

[0107] The Ni-based catalysts prepared in Example 1, Example 3 and Comparative Example 1 were used to evaluate the initial reaction rates with 5-hydroxymethylfurfural (HMF), furan dimethanol (BHF, the carbonyl hydrogenation product of HMF and also the key intermediate in the reaction), and 1-hydroxy-2,5-hexanedione (HHD, the ring-opening product of BHF, and intramolecular aldol condensation can obtain HCPN) as reactants, and the initial kinetics with BHF as the reactant was also evaluated.

[0108] The above reactions were all carried out on a YZPR-650 reactor of Shanghai Yanzheng Instrument Co., Ltd. After the reaction, the reactor body was placed in an ice-water bath to quickly quench and stop the reaction, and the reaction liquid was collected. Subsequently, N,N-dimethylformamide was added as an internal standard, and finally 1.5 mL of the reaction solution was aspirated with a syringe and transferred into a gas chromatography vial through a 0.22 μm nylon filter membrane for waiting analysis.

[0109] The reactants and product distribution were analyzed by an Agilent 8860 gas chromatograph equipped with a DB-WAX UI capillary column (30 m long, 0.32 mm inner diameter, 0.25 μm film thickness) and an FID (Flame Ionization Detector) to quantitatively analyze the hydrogenation rearrangement reaction products of HMF.

[0110] Evaluation conditions: Similar to Example 13, the difference is that the reaction conversion rate needs to be controlled ≤20% to avoid the influence of mass transfer.

[0111] By testing the conversion rate C of the reaction substrate of the evaluated catalyst i and the yield Y of the products of each reaction step j , the initial reaction rate TOF of different reaction paths was evaluated:

[0112]

[0113] The reaction order n and the activation energy Ea of the reaction are obtained by linear fitting from the following equations

[0114]

[0115] where C and B represent constant terms respectively, and R represents the gas constant of 8.314 J·mol -1 ·K -1 . The results are shown in Tables 2 and 3 below.

[0116] Table 2 Initial reaction rates of acid-Ni catalysts in the hydroisomerization of HMF system

[0117]

[0118] From the data in Table 2, it can be seen that in Comparative Example 1 without modified organic phosphonic acid, the ring-opening rearrangement reaction of the reaction intermediate BHF is the slowest step among all reaction steps, which also means that it is the rate-determining step of the reaction. While in Example 1 modified with MPA, the initial reaction rate of this step increased by an order of magnitude, reaching 561.1 h -1 . Such a fast ring-opening rearrangement rate enables BHF to be quickly converted into the intermediate product of ring-opening rearrangement, and thus the cyclic hydrogenation product BHTF that cannot be converted into HCPN cannot be generated anymore. Therefore, the selectivity of HCPN is also much higher than that of Comparative Example 1.

[0119] The above results show that the acid-Ni catalyst MPA-5Ni-Al prepared in Example 1 has good HCPN selectivity and catalytic activity. This improvement in selectivity is achieved by significantly accelerating the conversion rate of the rate-determining step of the reaction compared to 5Ni-Al (Comparative Example 1) without modified organic phosphonic acid.

[0120] Table 3 Initial reaction kinetic parameters of acid-Ni catalysts in the BHF reaction system

[0121]

[0122] As can be seen from the data in Table 3, the reaction orders of the ring hydrogenation and ring-opening rearrangement of the reaction intermediate BHF on the acid-metal Ni catalysts modified with organic phosphonic acids (Example 1 and Example 3) both decreased, which means that the adsorption of BHF on the acid-metal Ni catalysts modified with organic phosphonic acids is stronger than that on Comparative Example 1 (5Ni-Al), indicating that BHF is more likely to be adsorbed on the active sites of the catalyst and then react. Secondly, without obvious change in the activation energy of BHF ring hydrogenation, the activation energy of BHF ring-opening rearrangement decreased significantly on Example 1 and Example 3 modified with organic phosphonic acids. A lower activation energy means that thermodynamically, the BHF ring-opening rearrangement reaction is more likely to occur on the acid-metal Ni catalysts modified with organic phosphonic acids.

[0123] The above results show that the acid-Ni catalysts MPA-5Ni-Al and BPA-5Ni-Al prepared in Example 1 and Example 3 have lower BHF ring-opening activation energy and stronger adsorption on reactants, thus greatly increasing the reaction activity and the selectivity of HCPN. Example 15

[0124] Stability evaluation of organic phosphonic acid-Ni catalysts

[0125] Select Example 1, Example 5, and Example 9, and according to the catalytic performance test method of Example 13, evaluate the hydrothermal stability of the catalysts respectively, where: Y(HCPN) = *100%, and the results are shown in Table 4 below.

[0126] Table 4 Hydrothermal stability evaluation of acid-Ni catalysts

[0127]

[0128] As can be seen from the data in Table 4, compared with the MPA-5Ni-Al acid-Ni catalyst prepared in Example 1, the MPA-5Ni-MgAl catalysts (Example 5 and Example 9) still maintained the HMF conversion rate above 99.8% and the selectivity and yield of HCPN above 90.0% after 4 cycle experiments. The above results show that the acid-Ni catalysts prepared in Example 5 and Example 9 have good hydrothermal stability.

[0129] From the above stability tests, it can be seen that in the technical solution of the present invention, by adjusting the composition of the multi-layered material, the hydrothermal stability of the catalyst can be further optimized, thereby optimizing the application of the catalyst in industrial production.

[0130] Obviously, the above-mentioned embodiments of the present invention are only examples for clearly illustrating the present invention, rather than limitations on the implementation manners of the present invention. For those of ordinary skill in the art, other different forms of changes or variations can be made on the basis of the above description. It is impossible to enumerate all the implementation manners here. Any obvious changes or variations derived from the technical solutions of the present invention still fall within the scope of protection of this patent.

Claims

1. A method for preparing an acid-Ni catalyst for the hydrogenation and rearrangement of 5-hydroxymethylfurfural to produce 3-hydroxymethylcyclopentanone, characterized in that: The steps include: (1) preparing a precipitant of a certain concentration, adding an appropriate amount of nickel salt aqueous solution and aluminum salt aqueous solution under constant temperature stirring conditions, adding or not adding magnesium salt aqueous solution, maintaining the pH of the reaction system at 10±1, and then aging, filtering, washing, heat treating and grinding to obtain a Ni multi-layered material NiM, where M is selected from Al or MgAl; (2) dispersing the Ni multi-layered material NiM in an organic phosphonic acid solution, and obtaining a catalyst precursor PA / NiM through ligand self-assembly; (3) subjecting the catalyst precursor PA / NiM to thermal reduction treatment to obtain an acid-Ni catalyst PA-Ni-M; Wherein, in step (1), the molar ratio of Ni to Al ions is 1:(5-22); when a magnesium salt solution is added, the molar ratio of the sum of the molar amounts of Ni and Mg ions to Al ions is (0.5-4):1; In step (2), the mass ratio of the Ni multi-layered material NiM to the organic phosphonic acid is 3-8; the self-assembly comprises the following process: the mixed solution after dispersing the Ni multi-layered material NiM in the organic phosphonic acid solution is stirred at room temperature for 16-24 h, then centrifuged, heat treated at 100-160 ° C in flowing air for 4-8 h, washed and dried to obtain the catalyst precursor PA / NiM.

2. The preparation method according to claim 1, characterized in that: In step (1), the precipitant is selected from one of sodium carbonate aqueous solution, ammonia water or ammonium carbonate aqueous solution.

3. The preparation method according to claim 1, characterized in that In step (1), the specific process of aging, filtering, washing and heat treatment is: stirring continuously at 45-85°C for 12-24 hours, then filtering and washing with ultrapure water until neutral, and heat treating for 6-8 hours, wherein the heat treatment temperature is 160-220°C.

4. The preparation method according to claim 1, characterized in that: In step (1), the total molar concentration of the metal salt aqueous solution is 0.4-2.0M.

5. The preparation method according to claim 1, characterized in that: In step (2), the organic phosphonic acid is selected from one or more of methylphosphonic acid, dimethylphosphonic acid, butylphosphonic acid or benzylphosphonic acid.

6. The preparation method according to claim 1, characterized in that In step (2), the concentration of the organic phosphonic acid solution is 1.5-3.0 g / L.

7. The preparation method according to claim 1, characterized in that In step (3), the thermal reduction temperature is 400-600°C, and the residence time at the reduction temperature is 1-4 h.

8. An acid-Ni catalyst, characterized in that The method is prepared by any one of claims 1 to 7.

9. The acid-Ni catalyst according to claim 8, characterized in that In the acid-Ni catalyst, the Ni content is 4-10 wt%.

10. Use of the acid-Ni catalyst as claimed in claim 8 or 9, characterized in that: Used for the hydrogenation and rearrangement of 5-hydroxymethylfurfural to produce 3-hydroxymethylcyclopentanone.

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