A nano-confined Ni-Ru metal catalyst for hydrogenation and a preparation method and application thereof
By preparing nano-confined Ni-Ru catalysts, the problems of high cost of noble metal catalysts and easy aggregation of Ni-based catalysts were solved, realizing the hydrogenation reaction of organic liquid hydrogen storage materials with high efficiency and low cost. The catalyst has good cycle performance.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-11-21
- Publication Date
- 2026-03-27
AI Technical Summary
Existing precious metal catalysts are expensive, and Ni-based catalysts tend to agglomerate during the hydrogenation process of organic liquid hydrogen storage materials, resulting in low dispersion of the active components of the catalyst, which makes it difficult to meet the requirements of efficient hydrogenation.
Ni and Ru were loaded onto silica using metal complexation and impregnation methods, and nano-confined Ni-Ru catalysts were prepared by high-temperature calcination and reduction, achieving high dispersion and uniform fixation of the metals.
The catalyst exhibits a fast reaction rate, produces no byproducts, and can be reused multiple times, reducing the amount of precious metal Ru used, lowering costs, and improving the catalyst's activity and stability.
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Figure CN117599806B_ABST
Abstract
Description
TECHNICAL FIELD
[0001] The present application relates to the technical field of catalyst preparation, in particular to a nano-confined Ni-Ru metal catalyst for hydrogenation and a preparation method and application thereof. BACKGROUND
[0002] Hydrogen energy is an important energy related to the future development of the world, and hydrogen storage technology is a key factor restricting the large-scale use of hydrogen energy. Compared with traditional hydrogen storage methods, organic liquid hydrogen storage technology has attracted social attention due to its high hydrogen storage density, stability at room temperature and ambient pressure, low cost, and easy transportation. In the hydrogenation process of organic liquid hydrogen storage materials, the commonly used noble metal catalysts are expensive, which increases the technical cost. Therefore, it is crucial to find a more efficient and inexpensive catalyst.
[0003] Non-noble metal Ni is low in price and has a suitable electronic structure, so there are more studies on Ni-based hydrogenation catalysts at present. However, Ni-based catalysts applied in the hydrogenation process of organic liquid hydrogen storage materials often require high load, which easily leads to large-scale agglomeration of metal active components on the surface of the catalyst. Previous studies have shown that the introduction of metal additives can improve the dispersion of active metal components in the active catalyst, reduce the particle size, and enhance the catalytic activity. Zhu et al. introduced Ru as an additive into the Ni / C catalyst to obtain a Ru-Ni / C catalyst, and applied the catalyst to the catalytic hydrogenation of benzene, and the TOF value of the catalyst reached 7905 h -1 The characterization results of the Ru-Ni / C catalyst showed that the metal particle size on the catalyst was small (1-3 nm) and uniformly dispersed after the introduction of Ru, and there was a strong synergistic effect between Ni and Ru. In addition, studies have shown that the introduction of nitrogen-containing organic ligands can improve the dispersion of metal particles in the catalyst. Yang et al. complexed nitrogen-containing organic ligands with metal cations and adsorbed them onto commercial carbon black, and calcined to obtain a series of catalysts. Characterization results proved that the nitrogen-containing organic ligands could be pyrolyzed to produce C-N structures at high temperatures, in which N could bond with metal to anchor metal particles and promote the dispersion of metal particles. SUMMARY
[0004] Therefore, the present application provides a nano-confined Ni-Ru metal catalyst for hydrogenation and a preparation method and application thereof. The present application loads metal Ni and Ru on silica through metal complexation and impregnation, and obtains the target catalyst through high-temperature calcination reduction. The preparation process of the catalyst is mild, the required equipment is simple, the high dispersion and high utilization of metal on the non-noble metal catalyst are achieved, and the catalyst has good cycle performance.
[0005] The application provides a nano-limited Ni-Ru metal catalyst for hydrogenation, which is characterized by the following: the catalyst is prepared by using silica as a carrier, Ni metal as an active component and Ru metal as an additive; the pore volume of the catalyst is 0.8-1.1 cm 3 / g; the specific surface area of the catalyst is 400-1000 m 2 / g; the loading amount of Ni metal in the catalyst is 3 wt%; and the particle size of the Ni metal is 1.5-4 nm; the loading amount of Ru metal is 0.01-0.09 wt%.
[0006] Another object of the application is to provide a preparation method of the nano-limited Ni-Ru metal catalyst for hydrogenation.
[0007] (1) placing nickel salt, ruthenium salt and dicyandiamide in a container, adding ultrapure water, heating and stirring until completely dissolved to obtain a mixed solution, wherein the molar ratio of the sum of metal ions in the nickel salt and the ruthenium salt to dicyandiamide in the mixed solution is 2:1-30:1;
[0008] (2) weighing the silica carrier and adding it to the mixed solution in step (1), wherein the mass-to-volume ratio of the silica carrier to the mixed solution is 5-7 g:30-50 mL, and after uniform stirring, the catalyst precursor is obtained by drying at 50-70 ℃ for 6-10 h;
[0009] (3) grinding the catalyst precursor to obtain catalyst precursor powder; the particle size of the catalyst precursor powder is not required, and the catalyst precursor is crushed to facilitate subsequent processing;
[0010] (4) transferring the catalyst precursor powder in step (3) to a tube furnace, and calcining and reducing the catalyst precursor powder by introducing a mixed gas of inert gas and H2 for 3-5 h, and then placing and cooling to room temperature.
[0011] Preferably, the nickel salt is nickel nitrate or nickel chloride; and the ruthenium salt is ruthenium acetate or ruthenium trichloride.
[0012] Preferably, the heating temperature in step (1) is 50-70 ℃.
[0013] Preferably, the volume content of H2 in the mixed gas in step (4) is 10%, and the flow rate of the mixed gas is 200-500 mL / min.
[0014] Preferably, the calcination temperature in step (4) is 500-900 ℃.
[0015] The application further provides an application of the nano-limited Ni-Ru metal catalyst for hydrogenation in a hydrogenation reaction of an organic liquid hydrogen storage material.
[0016] Compared with the prior art, the application has the following beneficial effects:
[0017] (1) The Ni-Ru metal catalyst prepared by the present application can be applied to the hydrogenation reaction of liquid hydrogen storage material, and has a faster reaction rate, no by-product, and the catalyst can be repeatedly used for many times.
[0018] (2) The present application reduces the use amount of noble metal Ru, and greatly reduces the cost of the catalyst.
[0019] (3) The dispersion degrees of Ni and Ru are very high, and the active components are uniformly and firmly fixed on the surface of the catalyst carrier.
[0020] (4) The manufacturing process of the present application is simple, and the equipment requirement is not high, and it can be used for large-scale production. BRIEF DESCRIPTION OF DRAWINGS
[0021] Figure 1 It is the physical adsorption-desorption curve diagram of the nano-confined Ni-Ru metal catalyst in Example 1.
[0022] Figure 2 It is the pore size distribution diagram of the nano-confined Ni-Ru metal catalyst in Example 1.
[0023] Figure 3 It is the transmission electron microscope diagram of the nano-confined Ni-Ru metal catalyst in Example 1 with a scale of 500 nm.
[0024] Figure 4 It is the transmission electron microscope diagram of the nano-confined Ni-Ru metal catalyst in Example 1 with a scale of 20 nm.
[0025] Figure 5 It is the hydrogenation reaction rate diagram of the nano-confined Ni-Ru metal catalyst in Example 2 on nitrogen propyl carbazole.
[0026] Figure 6 It is the hydrogenation reaction rate diagram of the nano-confined Ni-Ru metal catalyst in Example 3 on nitrogen propyl carbazole.
[0027] Figure 7 It is the X-ray diffraction spectrum diagram of the catalyst prepared by using nickel acetate as the nickel source in Example 4
[0028] Figure 8 It is the X-ray diffraction spectrum diagram of the catalyst prepared by using ruthenium trichloride as the ruthenium source in Example 5
[0029] Figure 9 It is the hydrogenation reaction rate diagram of the nano-confined Ni-Ru metal catalyst in Example 6 on nitrogen ethyl carbazole.
[0030] Figure 10 It is the hydrogenation reaction rate diagram of the nano-confined Ni-Ru metal catalyst in Example 7 on dibenzyl toluene. DETAILED DESCRIPTION
[0031] The application provides a nano-confined Ni-Ru metal catalyst for hydrogenation and a preparation method and application thereof.
[0032] In specific embodiments of the application, the preparation method of the silica carrier is as follows:
[0033] ① 8.07 g of P123 template agent is placed in a 500 mL two-necked flask, 200 mL of deionized water and 41.7 mL of hydrochloric acid are added, and stirring is performed at 40℃ for 1 h;
[0034] ② 18.32 mL of tetraethyl orthosilicate (TEOS) is slowly added dropwise to the obtained mixed solution, and stirring is continuously performed for 24 h;
[0035] ③ The obtained solution is transferred into a 500 mL hydrothermal reactor, and after hydrothermal treatment at 100℃ for 48 h, natural cooling to room temperature is performed, and the product is taken out;
[0036] ④ The product is washed with deionized water until neutral, and dried in an oven at 80℃ overnight;
[0037] ⑤ The obtained white powder is transferred into a porcelain boat, calcination is performed at 550℃ in a muffle furnace for 10 h to remove the template agent, cooling to room temperature is performed, and the product is taken out and crushed to obtain the silica carrier.
[0038] The application is further described below in combination with examples.
[0039] Example 1
[0040] A preparation method of a nano-confined Ni-Ru metal catalyst for hydrogenation is as follows:
[0041] (1) 1.566 g of nickel nitrate hexahydrate (Ni(NO3)2·6H2O, Mw=290.79 g / mol), 0.015 g of ruthenium acetate (Ru wt%=40-45, Mw=732.52) and 0.9156 g of dicyanamide (C2H4N4, Mw=84.08 g / mol) are weighed and placed in a 100 mL beaker, 40 mL of Up water is added, the temperature is increased to 60℃, and heating and stirring are performed until complete dissolution to obtain a mixed solution;
[0042] (2) 6.000 g of the silica carrier is weighed and added to the mixed solution in step (1), and stirring is uniformly performed with a medicine spoon, at this time, the solid is in the form of dark green mud, and the uniformly stirred solid is placed in an oven and dried at 60℃ for 8 h to obtain a dark green powder, which is the catalyst precursor;
[0043] (3) The catalyst precursor is ground to obtain a catalyst precursor powder;
[0044] (4) The catalyst precursor powder in step (3) is transferred into a tube furnace, Ar / H2 (H2 volume content is 10%) mixed gas is passed in, the mixed gas flow rate is set to 350 mL / min, calcination reduction is carried out at 700°C for 4h, and the nano-confined Ni-Ru metal catalyst for hydrogenation is obtained.
[0045] The Ni metal loading in the catalyst is 3wt%, and the Ru metal loading is 0.03wt%.
[0046] The physical adsorption and desorption curve of the catalyst is as shown in Figure 1 The pore size distribution of the catalyst is as shown in Figure 2 From Figure 1 and Figure 2 it can be seen that the specific surface area of the new Ni-Ru catalyst is 600-700m 2 / g, the pore volume is 1.0-1.1cm 3 / g, and the pore size is 6.0-8.0nm. Figure 3 and Figure 4 are electron microscope images of the catalyst at different magnifications, from Figure 3 and Figure 4 it can be seen that the particle size of the metal Ni nanoparticles on the catalyst is 1.5-4nm.
[0047] Example 2
[0048] The nano-confined Ni-Ru metal catalyst for hydrogenation prepared in Example 1 is used to carry out hydrogenation experiments on organic liquid hydrogen storage materials.
[0049] The catalyst is added in an amount of 0.2g, the hydrogen storage material is 2.0g of nitrogen propyl carbazole, 40ml of cyclohexane is added as a solvent, the reaction pressure is 7MPa, the reaction temperature is 150°C, the rotation speed is 10rev / s, and the reaction time is 60min, so that the nitrogen propyl carbazole is completely hydrogenated, and there is no other by-product.
[0050] The hydrogenation reaction rate of the catalyst on nitrogen propyl carbazole is as shown in Figure 5 .
[0051] Example 3
[0052] The nano-confined Ni-Ru metal catalyst for hydrogenation prepared in Example 1 is used to carry out cyclic hydrogenation experiments on organic liquid hydrogen storage materials.
[0053] The catalyst is added in an amount of 0.2g, and the hydrogen storage material is 2.0g of nitrogen propyl carbazole each time the hydrogenation performance test is carried out, 40ml of cyclohexane is added as a solvent, the reaction pressure is 7MPa, the reaction temperature is 150°C, and the rotation speed is 10rev / s.
[0054] The hydrogenation data results are as shown in Figure 6The results are shown in Table 1. From Table 1, it can be seen that the hydrogenation performance of the catalysts gradually decreased with the increase of the number of cycles, but the hydrogenation was basically completed within 180 min, indicating that the catalysts can be used for multiple cycles. Figure 6
[0055] Example 4
[0056] A preparation method of a nano-confined Ni-Ru metal catalyst for hydrogenation, the steps being as in Example 1, the only difference being that the nickel nitrate is replaced by nickel chloride, the ruthenium acetate remains unchanged, and the molar ratio remains unchanged.
[0057] The Ni metal loading in the catalyst is 3wt%, the Ru metal loading is 0.03wt%, the specific surface area is 600-700m 2 / g, the pore volume is 1.0-1.1cm 3 / g, and the pore size is 6.0-8.0nm.
[0058] The XRD pattern of the catalyst is shown in Figure 2. Figure 7 .
[0059] Figure 7 In Figure 2, only a broad peak corresponding to silicon dioxide appears, and no peak of any metal or metal compound appears, indicating that the synthesized catalyst has good dispersity.
[0060] Example 5
[0061] A preparation method of a nano-confined Ni-Ru metal catalyst for hydrogenation, the steps being as in Example 1, the only difference being that the ruthenium acetate is replaced by ruthenium trichloride, the nickel nitrate remains unchanged, and the molar ratio remains unchanged.
[0062] The Ni metal loading in the catalyst is 3wt%, the Ru metal loading is 0.03wt%, the specific surface area is 600-700m 2 / g, the pore volume is 1.0-1.1cm 3 / g, and the pore size is 6.0-8.0nm.
[0063] The XRD pattern of the catalyst is shown in Figure 2. Figure 8 .
[0064] Figure 8 In Figure 2, only a broad peak corresponding to silicon dioxide appears, and no peak of any metal or metal compound appears, indicating that the synthesized catalyst has good dispersity.
[0065] Example 6
[0066] Example 2 is repeated, the only difference being that the nitrogen propyl carbazole is replaced by nitrogen ethyl carbazole (NECZ), and the catalyst used and the hydrogenation conditions remain unchanged. The hydrogenation performance test results are shown in Table 1. Figure 9 As shown in Table 2, the results show that the catalyst has good hydrogenation effect on nitrogen ethyl carbazole.
[0067] Example 7
[0068] Example 2 is repeated, with the only difference being that nitrogen propyl carbazole is replaced by dibenzyl toluene (DBT), and the catalyst and hydrogenation conditions remain unchanged. The hydrogenation performance test results are shown in Table 3. Figure 10 As shown in Table 3, the results show that the catalyst has good hydrogenation effect on dibenzyl toluene.
[0069] The above-described examples are only used to describe the preferred modes of the present application, and are not intended to limit the scope of the present application. Without departing from the design spirit of the present application, various modifications and improvements to the technical solutions of the present application made by those of ordinary skill in the art should fall within the protection scope defined by the claims of the present application.
[0070] The above-described examples are only preferred embodiments of the present application. It should be noted that, for those of ordinary skill in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements should also be considered within the protection scope of the present application.
Claims
1. A nano-confined Ni-Ru metal catalyst for hydrogenation, characterized in that, The catalyst uses silica as a support, Ni metal as the active component, and Ru metal as a promoter. The catalyst pore volume is 0.8-1.1 cm³. 3 / g, specific surface area is 400-1000 m² 2 / g, the catalyst has a Ni metal loading of 3wt%, and the particle size of the Ni metal particles loaded on the catalyst is 1.5-4nm; the Ru metal loading is 0.01-0.09wt%; The method for preparing the aforementioned nano-confined Ni-Ru metal catalyst for hydrogenation includes the following steps: (1) Place nickel salt, ruthenium salt and dicyandiamide in a container, add ultrapure water, heat and stir until completely dissolved to obtain a mixed solution. The molar ratio of the sum of metal ions of nickel salt and ruthenium salt to dicyandiamide in the mixed solution is 2:1-30:
1. (2) Weigh the silica support and add it to the mixed solution in step (1), wherein the mass-volume ratio of the silica support to the mixed solution is 5-7g:30-50mL. After stirring evenly, dry at 50-70℃ for 6-10h to obtain the catalyst precursor. (3) Grind the catalyst precursor to obtain catalyst precursor powder; (4) Transfer the catalyst precursor powder from step (3) to a tube furnace, introduce a mixture of inert gas and H2 and calcine and reduce it for 3-5 h, and then let it cool to room temperature.
2. The nano-confined Ni-Ru metal catalyst for hydrogenation according to claim 1, characterized in that, The nickel salt is nickel nitrate or nickel chloride; the ruthenium salt is ruthenium acetate or ruthenium trichloride.
3. The nano-confined Ni-Ru metal catalyst for hydrogenation according to claim 1, characterized in that, The heating temperature in step (1) is 50-70℃.
4. The nano-confined Ni-Ru metal catalyst for hydrogenation according to claim 1, characterized in that, In step (4), the volume content of H2 in the mixed gas is 10%, and the gas flow rate of the mixed gas is 200-500 mL / min.
5. The nano-confined Ni-Ru metal catalyst for hydrogenation according to claim 1, characterized in that, The calcination temperature in step (4) is 500-900℃.
6. The application of the nano-confined Ni-Ru metal catalyst for hydrogenation according to claim 1 in the hydrogenation reaction of organic liquid hydrogen storage materials.
Citation Information
Patent Citations
Preparation method and catalytic application of supported high-dispersity NiRu bimetallic catalyst
CN106423199A