Preparation method of Ru catalyst for preparing hydrogenated bisphenol A through bisphenol A hydrogenation

Abstract

The invention discloses a preparation method of a Ru catalyst for preparing hydrogenated bisphenol A through bisphenol A hydrogenation. The preparation method comprises the following steps: S1, mixing a penetration enhancer, a nitrogen-containing compound and water to prepare a modified solution, dipping aluminum oxide in the modified solution, then carrying out ultrasonic treatment, carrying out a reaction, and after the reaction is finished, carrying out drying and roasting to obtain a modified aluminum oxide carrier; s2, preparing a ruthenium-containing steeping liquor, placing the modified alumina carrier in the ruthenium-containing steeping liquor for steeping, and then drying and roasting to obtain a Ru catalyst precursor; and S3, reducing the Ru catalyst precursor to obtain a reduced Ru catalyst. According to the method, an aluminum oxide carrier is modified through a nitrogen-containing compound, nitrogen species serve as anchoring sites so as to react with ruthenium metal ions, and Ru is stably and highly dispersed on the surface and in pores of aluminum oxide in a complexing mode.

Description

Technical Field

[0001] The present invention belongs to the technical field of hydrogenation catalysts, and particularly relates to a preparation method of a Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. Background Art

[0002] Bisphenol A is an industrial compound widely used in the production of high molecular materials such as polycarbonate (PC) and epoxy resin. Due to the reproductive toxicity of bisphenol A, its alternative product, hydrogenated bisphenol A, is prepared by continuous hydrogenation under the action of a catalyst to completely saturate the two benzene rings. For this reaction, in the prior art, ruthenium is often used as the active metal and alumina as the carrier for the hydrogenation catalyst. However, for noble metal-supported catalysts, there is often a problem of low effective utilization rate of the metal caused by poor dispersion of the active component, which will seriously affect the catalytic activity of the catalyst. To improve the dispersion of noble metals, the main methods currently used include: modifying the alumina carrier, forming metal complexes, and embedding the metal, etc. Among them, the method of modifying the alumina carrier has a simple operation method and a wide range of applicable raw materials, so it has better practical application value.

[0003] CN110947379A discloses a ruthenium catalyst capable of carrying out catalytic hydrogenation reaction at room temperature. The ruthenium trichloride solution is mixed with α-Al 2 O 3 and then ultrasonicated and impregnated in a vacuum drying oven, and then dried and calcined in an inert atmosphere. The average particle size of metallic ruthenium on the catalyst prepared by this method is about 3 nm, which belongs to the state of metal clusters, and the dispersion of ruthenium is not high enough to give full play to the full effect of ruthenium metal.

[0004] CN113304763A uses a sodium hydroxide solution to impregnate to obtain alkali-modified alumina. After impregnating with a noble metal solution, it is soaked with a hydrazine hydrate solution, and then adsorbed and dried with a main group element salt solution and a transition metal salt solution to obtain a catalyst for the preparation of aminoanthraquinone. This catalyst shows high conversion and selectivity in the catalytic hydrogenation evaluation. Using alkali treatment of alumina cannot play a role in improving metal dispersion such as dredging pores, and the noble metal and the main group element and transition metal elements are introduced successively on this catalyst, which may cause problems such as stacking of metal particles and is prone to form alloys at higher reaction temperatures, which is not conducive to the long-term stability of the catalyst.

[0005] CN115920926A deposits nickel and tungsten elements on alumina and calcines it, then impregnates ruthenium on the metal-modified alumina support, and obtains a ruthenium hydrogenation catalyst after hydrogen reduction. The synergistic effect among the three metal elements helps to improve the dispersion of the active component, and at the same time the metal promoter can increase the acidity of the catalyst. On this ruthenium-based dual-promoter hydrogenation catalyst, the metal elements are dispersed through synergistic effects. The force of this synergistic effect is weak, and the dispersion effect of ruthenium is relatively general, making it difficult to achieve the effect of atomic-level dispersion. Moreover, during the reaction process, it is also extremely easy to migrate and form agglomerated metal clusters.

[0006] CN102476052A impregnates a support such as alumina with a soluble alkaline earth metal salt and then calcines it, and uses the impregnation method to load ruthenium and other metal promoters on the support, and obtains a supported ruthenium catalyst after reduction. Modifying alumina with an alkaline earth metal salt may block the pores, and at the same time the alkali metal oxide after calcination is also difficult to interact with ruthenium, so it will affect the dispersion performance of ruthenium on the catalyst and make it difficult to achieve the effect of atomic-level dispersion.

[0007] CN105107496A divides the ruthenium metal salt solution into two halves and adds them to alumina powder successively. After each addition, it is fully stirred and the pH is adjusted within the range of 8-12. After reduction with a reducing agent and washing and drying, a ruthenium-alumina catalyst is obtained. When half of the ruthenium salt solution is successively impregnated on alumina powder, without introducing protection such as promoters, the distribution of ruthenium metal may be uneven and the dispersion effect is general. At the same time, without isolation protection measures, metal agglomeration is also extremely easy to occur under reaction conditions.

[0008] CN103706395A coordinates ruthenium salt with four functionalized promoters and then combines it with the support, and realizes the effects of smaller particle size and uniform dispersion of the reduced ruthenium through an embedding agent, thereby improving the catalytic activity. The coordination compound formed by coordinating ruthenium with the promoter has a relatively large molecular spatial volume, and the metal is easily deposited on the surface of the support and difficult to enter the pores. At the same time, the introduction of the embedding agent will block the pores on the one hand, reduce the pore structure properties of the support, and also increase the cost. Summary of the Invention

[0009] The object of the present invention is to provide a preparation method of a Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. The support alumina is modified with a nitride, and the nitride forms anchoring sites on the surface and in the pores of the alumina, promotes the highly dispersed ruthenium metal particles on the inner and outer surfaces of the support, increases the effective utilization rate of ruthenium metal, helps the contact between bisphenol A molecules and active sites, thereby promoting the catalytic hydrogenation reaction, and ultimately can improve the activity of the ruthenium-based catalyst.

[0010] To achieve the above object, the present invention provides a preparation method of a Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A, including the following steps:

[0011] S1. Mix a penetration enhancer, a nitrogen-containing compound, and water to prepare a modified solution. Immerse alumina in the modified solution, then perform ultrasonic treatment and react. After the reaction, dry and calcine to obtain a modified alumina support.

[0012] S2. Prepare a ruthenium-containing impregnation solution, and immerse the modified alumina support in the ruthenium-containing impregnation solution, then dry and calcine to obtain a Ru catalyst precursor.

[0013] S3. Reduce the Ru catalyst precursor to obtain a reduced Ru catalyst.

[0014] In the preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to the present invention, the nitrogen-containing compound is a substance containing one or more functional groups among amino group, piperidyl group, pyridyl group, and piperazinyl group.

[0015] In the preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to the present invention, the nitrogen-containing compound is one or more of 1,10-phenanthroline, aminoacridine hydrochloride, 3,4-dihydro-7-hydroxy-2(1H)-quinolinone, glycine, proline, and lysine.

[0016] In the preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to the present invention, the concentration of the nitrogen-containing compound in the modified solution is 0.025 - 5 mol / L.

[0017] In the preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to the present invention, the penetration enhancer is an alcohol and / or a azone compound. The alcohol compound is one or more of methanol, ethanol, and menthol, and the azone compound is azone.

[0018] In the preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to the present invention, the mass ratio of the penetration enhancer to water in the modified solution is 1:50 - 50:1.

[0019] In the preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to the present invention, in step S1, the immersion is carried out at 20 - 30 °C, and the reaction after ultrasonic treatment is carried out at 40 - 120 °C for 0.5 - 8 h; the calcination conditions are calcination treatment at 200 - 700 °C for 2 - 8 h under the protection of an inert gas.

[0020] In the preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to the present invention, in step S2, the calcination conditions are calcination treatment at 150 - 600 °C for 1 - 6 h.

[0021] The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. In step S3, the reduction conditions are reduction at 120 - 300 °C for 0.5 - 6 h under a hydrogen atmosphere.

[0022] The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A. Use one or more of ruthenium nitrosyl nitrate, ruthenium trichloride, and ruthenium acetate to prepare a ruthenium-containing impregnation solution, and the concentration of ruthenium compound in the ruthenium-containing impregnation solution is 0.005 - 0.05 mol / L.

[0023] Advantages of the present invention:

[0024] By modifying the alumina support with a nitrogen-containing compound, the nitrogen species serve as anchoring sites to facilitate the reaction with ruthenium metal ions, and Ru is stably and highly dispersed on the surface and in the pores of the alumina by complexation.

[0025] After the alumina is modified with a nitrogen-containing compound, since the molecular structure of the nitride provided by the present invention is small, it can diffuse inside and outside the pores of the alumina. After calcination in an inert gas, the nitrogen species on the surface or in the pores can serve as anchoring sites to coordinate with Ru ions to form a stable chelate. After calcination and reduction, Ru metal particles are stably and widely dispersed on the inner and outer surfaces of the support. The bisphenol A molecule with a diameter of 0.9 nm can freely diffuse inside and outside the pores of the support, so the contact rate between the Ru active site and the bisphenol A molecule is increased. At the same time, by selecting nitrides with different molecular weights and molecular structures, the distance between Ru atoms can be orderly and precisely regulated. Therefore, modifying the alumina with a nitrogen-containing compound helps to improve the dispersion of Ru particles and the metal utilization rate, thereby helping to improve the reaction effect of the catalyst.

[0026] The Ru catalyst prepared by this method stably and highly disperses Ru on the inner and outer surfaces of the support through a nitrogen-containing compound, reducing the phenomenon of Ru atom agglomeration on the alumina support and the contradiction between the metal loading amount and the dispersion degree in the prior art, effectively improving the Ru metal utilization rate and dispersion, and thus helping to improve the activity of the catalyst in the bisphenol A hydrogenation reaction. Description of the drawings

[0027] Figure 1 is the aberration-corrected electron microscopy image of Ru-N / Al 2 O 3 obtained in Example 1 of the present invention;

[0028] Figure 2 is the aberration-corrected electron microscopy image of the ruthenium catalyst obtained in Comparative Example 1 of the present invention;

[0029] Figure 3 is the aberration-corrected electron microscopy image of the ruthenium catalyst obtained in Comparative Example 2 of the present invention. Detailed implementation manners

[0030] The present invention will be specifically described below through embodiments. It is necessary to point out here that the following embodiments are only used to further illustrate the present invention and cannot be construed as limiting the protection scope of the present invention. Those skilled in the art can make some non-essential improvements and adjustments to the present invention based on the above content of the present invention.

[0031] Example 1

[0032] Weigh 0.147 g of o-phenanthroline and add it to a mixed solvent of 5.0 g of absolute ethanol and 0.1 g of deionized water to form a homogeneous solution. Weigh 5 g of strip-shaped alumina and place it in the homogeneous solution. Immerse it at 20 °C for 5 min, then ultrasonicate for 10 min and react at 120 °C for 0.5 h. After drying the sample, heat-treat it in a muffle furnace at 400 °C for 4 h under N 2 atmosphere for 4 h, cool it to room temperature and take it out to obtain a modified alumina support denoted as Al-1. Measure 0.07 g of nitrosyl ruthenium nitrate solution (ruthenium content is 31.3%), add 5 g of deionized water and mix evenly, then transfer it to the Al-1 support and mix well. Dry it at 80 °C for 6 h and calcine it in a muffle furnace at 400 °C for 4 h. Then reduce it in a hydrogen atmosphere at 140 °C for 2 h to obtain a reduced Ru catalyst cal-1.

[0033] Example 2

[0034] Weigh 0.978 g of aminoacridine hydrochloride and add it to 25.0 g of deionized water and 0.5 g of menthol to form a homogeneous solution. Weigh 10 g of spherical alumina and place it in the homogeneous solution. Immerse it at 30 °C for 5 min, then ultrasonicate for 30 min and react at 40 °C for 5 h. After constant-temperature drying, heat-treat it in a muffle furnace at 600 °C for 3 h under N 2 atmosphere, cool it to room temperature and take it out to obtain a modified alumina support denoted as Al-2. Weigh 0.0513 g of ruthenium trichloride, add 5 g of deionized water and mix evenly, then transfer it to the Al-2 support and mix well. Dry it at 80 °C for 6 h and calcine it in a muffle furnace at 300 °C for 5 h. Then reduce it in a hydrogen atmosphere at 140 °C for 2 h to obtain a reduced Ru catalyst cal-2.

[0035] Example 3

[0036] Weigh 0.137 g of proline and 0.07 g of lysine in a beaker, add 25 g of deionized water, 25 g of ethanol and 0.125 g of azone, and prepare a 50 mmol homogeneous solution. Weigh 5 g of strip-shaped alumina and place it in the homogeneous solution. Immerse it at 20 °C for 5 min, then ultrasonicate for 20 min and react at 80 °C for 8 h. After constant-temperature drying, heat-treat it in a muffle furnace at N 2Heat-treat at 700 °C for 6 h under an atmosphere, cool to room temperature and take out to obtain a modified alumina support denoted as Al-3. Weigh 0.038 g of ruthenium trichloride, add 5 g of deionized water and mix evenly, then transfer to the Al-3 support and mix thoroughly, dry at 80 °C for 6 h, and calcine in a muffle furnace at 600 °C for 1 h. Then reduce at 140 °C for 2 h under a hydrogen atmosphere to obtain a reduced Ru catalyst cal-3.

[0037] Example 4

[0038] Weigh 3.76 g of glycine into a beaker, add 10 g of deionized water and 0.2 g of ethanol to form a homogeneous solution. Weigh 8.5 g of strip-shaped alumina and place it in the homogeneous solution, impregnate at 20 °C for 5 min, then ultrasonicate for 10 min, and react at 60 °C for 4 h. After constant-temperature drying, heat-treat in a muffle furnace at N 2 Heat-treat at 200 °C for 8 h under an atmosphere, cool to room temperature and take out to obtain a modified alumina support denoted as Al-4. Weigh 0.014 g of ruthenium acetate, add 10 g of deionized water and mix evenly, then transfer to the Al-4 support and mix thoroughly, dry at 120 °C for 2 h, and calcine in a muffle furnace at 150 °C for 6 h. Then reduce at 140 °C for 2 h under a hydrogen atmosphere to obtain a reduced Ru catalyst cal-4.

[0039] Example 5

[0040] Weigh 0.0816 g of 3,4-dihydro-7-hydroxy-2(1H)-quinolinone, add 0.2 g of deionized water and 10 g of methanol to form a homogeneous solution. Weigh 13 g of strip-shaped alumina and place it in the homogeneous solution, impregnate at 20 °C for 5 min, then ultrasonicate for 20 min, and react at 80 °C for 3 h. After constant-temperature drying, heat-treat in a muffle furnace at N 2 Heat-treat at 350 °C for 4 h under an atmosphere, cool to room temperature and take out to obtain a modified alumina support denoted as Al-5. Weigh 0.05 g of nitrosyl ruthenium nitrate solution (ruthenium content is 31.3%), add 10 g of deionized water and mix evenly, then transfer to the Al-5 support and mix thoroughly, dry at 100 °C for 3 h, and calcine in a muffle furnace at 350 °C for 4 h. Then reduce at 140 °C for 2 h under a hydrogen atmosphere to obtain a reduced Ru catalyst cal-5.

[0041] Comparative Example 1

[0042] For the ruthenium catalyst prepared in Comparative Example 1, referring to the preparation method of CN110975908A, weigh 0.0513 g of anhydrous ruthenium trichloride crystals and add 5.0 g of deionized water, ultrasonicate for 5 min until completely dissolved and dispersed evenly. Weigh 5 g of α-Al 2 O 3It was added to the ruthenium trichloride solution, stirred, and then sonicated for 15 min. After that, it was sealed with tin foil and impregnated in a vacuum drying oven at room temperature for 24 h. Then it was placed in an oven and dried at 105 °C for 12 h. Then it was reduced at 140 °C in a hydrogen atmosphere for 2 h to obtain the comparative sample D-1. In the preparation method of this patent, there is no nitride modification step for alumina.

[0043] Comparative Example 2

[0044] For the ruthenium catalyst prepared in Comparative Example 2, referring to the preparation method of CN102476052A, 0.25 g of calcium nitrate was weighed and added to 5 g of deionized water and stirred evenly. 5 g of spherical alumina was weighed and added thereto for equal-volume impregnation. Then it was dried at 100 °C for 6 h and then calcined at 650 °C for 5 h. It was naturally cooled to room temperature and taken out to obtain an alkaline earth-modified alumina support. 0.0513 g of anhydrous ruthenium trichloride was weighed, added to 5 g of deionized water and mixed evenly, and then impregnated on the alkaline earth-modified alumina support in an equal volume. It was dried at 100 °C for 10 h. Then it was reduced at 140 °C in a hydrogen atmosphere for 2 h to obtain the comparative sample D-2. In the preparation method of this patent, the modification of alumina lies in impregnation with alkaline earth metal salts.

[0045] Comparative Example 3

[0046] 0.147 g of o-phenanthroline was weighed and added to a mixed solvent of 0.5 g of absolute ethanol and 5 g of deionized water to form a homogeneous solution. 5 g of strip-shaped alumina was weighed and placed in the homogeneous solution and impregnated at 20 °C for 5 min, then dried and heat-treated in a muffle furnace at 400 °C for 4 h, and taken out after cooling to room temperature to obtain a modified alumina support denoted as D-3. 0.07 g of nitrosyl ruthenium nitrate solution (ruthenium content is 31.3%) was weighed, added to 5 g of deionized water and mixed evenly, and then transferred to the D-3 support and mixed thoroughly. It was dried at 80 °C for 6 h and calcined in a muffle furnace at 400 °C for 4 h. Then it was reduced at 140 °C in a hydrogen atmosphere for 2 h to obtain the comparative sample D-3.

[0047] The electron microscopes of the ruthenium catalysts obtained in Example 1 and Comparative Examples 1 and 2 are as Figure 1 、 Figure 2 and 3 shown. It can be seen from the pictures that the method provided by the present invention can make ruthenium metal particles highly dispersed on the surface of the support. This is because the nitrogen species on the surface of the alumina support make it easier for Ru metal particles to combine with N species during deposition, effectively avoiding their agglomeration, thereby effectively improving the metal utilization rate of the ruthenium catalyst. Relatively speaking, the Ru metal clusters in Comparative Examples 1 and 2 are relatively large, indicating a weaker degree of dispersion.

[0048] The fixed-bed reactor was used to evaluate the reaction of catalytic hydrogenation of bisphenol A to prepare hydrogenated bisphenol A with catalyst samples cal-1, cal-2, cal-3, cal-4, cal-5, D-1, D-2, and D-3. The specific reaction process conditions were as follows: reaction pressure 4 MPa, temperature 150 °C, space velocity 0.5 h -1 , and hydrogen-oil volume ratio 500:1. The evaluation results are shown in Table 1 below.

[0049] Table 1 Evaluation Results

[0050] catalyst conversion rate cal-1 85％ cal-2 82％ cal-3 86％ cal-4 84％ cal-5 84％ D-1 66％ D-2 68％ D-3 73％

[0051] Of course, the present invention may have many other embodiments. Without departing from the spirit and essence of the present invention, those skilled in the art can make various corresponding changes and modifications according to the present invention. However, these corresponding changes and modifications should all fall within the protection scope of the claims of the present invention.

Claims

1. A preparation method of a Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A, characterized in that, it includes the following steps: S1, Mix a penetration promoter, a nitrogen-containing compound and water to prepare a modified solution. Immerse alumina in the modified solution, then perform ultrasonic treatment and react. After the reaction, dry and calcine to obtain a modified alumina support; S2, Prepare a ruthenium-containing impregnation solution, and immerse the modified alumina support in the ruthenium-containing impregnation solution, then dry and calcine to obtain a Ru catalyst precursor; S3, Reduce the Ru catalyst precursor to obtain a reduced Ru catalyst.

2. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, the nitrogen-containing compound is a substance containing one or more functional groups of amino group, piperidyl group, pyridyl group and piperazinyl group.

3. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, the nitrogen-containing compound is one or more of 1,10-phenanthroline, aminoacridine hydrochloride, 3,4-dihydro-7-hydroxy-2(1H)-quinolinone, glycine, proline and lysine.

4. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, the concentration of the nitrogen-containing compound in the modified solution is 0.025 - 5 mol / L.

5. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, the penetration promoter is an alcohol and / or an azone compound. The alcohol compound is one or more of methanol, ethanol and menthol, and the azone compound is azone.

6. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, the mass ratio of the penetration promoter to water in the modified solution is 1:50 - 50:

1.

7. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, in step S1, the impregnation is carried out at 20 - 30 °C, and the reaction after ultrasonic treatment is carried out at 40 - 120 °C for 0.5 - 8 h; the calcination conditions are calcination treatment at 200 - 700 °C for 2 - 8 h under inert gas protection.

8. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, in step S2, the calcination conditions are calcination treatment at 150 - 600 °C for 1 - 6 h.

9. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, in step S3, the reduction conditions are reduction at 120 - 300 °C for 0.5 - 6 h in a hydrogen atmosphere.

10. The preparation method of the Ru catalyst for the hydrogenation of bisphenol A to prepare hydrogenated bisphenol A according to claim 1, characterized in that, Prepare a ruthenium-containing impregnation solution using one or more of ruthenium nitrosyl nitrate, ruthenium trichloride, and ruthenium acetate, with the concentration of ruthenium compound in the ruthenium-containing impregnation solution being 0.005 - 0.05 mol / L.

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