Cyclic hydrocarbon selective hydrogenation ring-opening catalyst and preparation and application thereof
By using atomic dispersed precious metal catalyst coated with Y-type molecular sieve, the problem of difficulty in converting fused ring hydrocarbons in the prior art is solved, and efficient selective hydrogenation and ring opening reaction of cyclic hydrocarbons is achieved, which improves the cetane number and quality of the oil product.
Patent Information
- Application Number
- CN202311771010.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2023-12-21
- Publication Date
- 2025-06-24
Abstract
Description
Technical Field
[0001] The present invention relates to a catalyst for selective hydrogenation ring-opening of cycloalkanes and a preparation method thereof, and more specifically to a Y-type molecular sieve-coated atomically dispersed noble metal catalyst, in which noble metal atoms are dispersed in the supercages of the molecular sieve. This catalyst is applied to the selective hydrogenation ring-opening reaction of cycloalkanes and exhibits high cycloalkane hydrogenation ring-opening activity and selectivity in the range of 220 - 300 °C. Background Art
[0002] China's energy structure is rich in coal, poor in oil, and scarce in gas. Therefore, the efficient and clean utilization of coal resources is an important measure to solve China's economic and energy security. Coal-to-liquid technology is an important part of modern coal chemical industry. In-depth research on coal-to-liquid technology and oil products conforms to the development prospect of China's coal chemical industry. However, coal tar and directly liquefied coal oils contain a large amount of polycyclic hydrocarbons, which have characteristics such as high density and low cetane number, restricting their use as high-quality diesel. Therefore, it is urgent to convert them into chain hydrocarbons through the selective hydrogenation ring-opening reaction of cycloalkanes to increase the cetane number and improve the quality of oil products. Summary of the Invention
[0003] The present invention aims to provide a catalyst for selective hydrogenation ring-opening of cycloalkanes. This catalyst is a Y-type molecular sieve-coated atomically dispersed noble metal catalyst, which exhibits excellent hydrogenation ring-opening activity and selectivity under the conditions of 220 - 300 °C, 1 - 7 MPa, and 0.5 - 5 h -1 conditions.
[0004] Based on the above purpose, the technical solution adopted by the present invention is as follows:
[0005] 1. A catalyst for selective hydrogenation ring-opening of cycloalkanes, characterized in that the composition of the catalyst is M@Y molecular sieve, where M is atomically dispersed in the supercages of the Y molecular sieve.
[0006] 2. M is one of Ru, Rh, Pt, Pd, and the mass percentage is: 0.1% - 5%.
[0007] 3. The preparation method of the M@Y molecular sieve catalyst is as follows:
[0008] (1) Mix the aluminum source, water, and alkali source and stir evenly;
[0009] (2) Add the noble metal precursor solution;
[0010] (3) After adding the alkali-treated silicon source, continue to stir the mixed system for 2 - 12 hours, and then stand for aging for 6 - 24 hours;
[0011] (4) Transfer the solution obtained in step (3) to a hydrothermal autoclave and perform hydrothermal treatment for 12 - 72 hours;
[0012] (5) Filter out the solid substance obtained in step (4), wash it three times with water and ethanol respectively, and then dry it;
[0013] (6) Calcinate the solid obtained in step (5) to obtain the M@Y zeolite catalyst.
[0014] 4. In step (1), the aluminum source is one of aluminum isopropoxide and sodium aluminate, the base source is tetrapropylammonium hydroxide, and the mass ratio of the aluminum source, the base source, and water is 1:2 - 30:100 - 400, preferably 1:3 - 18:200 - 350; in step (2), the noble metal precursor is one of tris(ethylenediamine)ruthenium chloride, tris(ethylenediamine)rhodium trichloride, ethylenediamineplatinum chloride, and ethylenediaminepalladium chloride; in step (3), the base is one of NaOH, KOH, and ammonia water, and the mass ratio of the base and the silicon source is 0.01 - 15, preferably 1 - 13. The base treatment process is heating under reflux, and the molar mass ratio of the silicon source and the aluminum source is 50 - 150:1.
[0015] 5. The hydrothermal treatment temperature in step (4) is 80 - 220 °C; the calcination temperature in step (6) is 300 - 600 °C, and the calcination time is 2 - 12 hours.
[0016] 6. The M@Y zeolite catalyst is applied to the selective hydrogenation ring-opening reaction of cycloalkanes. The reaction temperature is 220 - 300 °C, the pressure is 1 - 7 MPa, the liquid hourly space velocity is 0.5 - 5 h -1 , and the hydrogen-oil ratio is 200 - 20000.
[0017] The selective hydrogenation ring-opening catalyst of the M@Y zeolite catalyst prepared by the present invention has relatively high activity and ring-opening selectivity, and good catalyst stability. Specific Embodiments
[0018] In order to further illustrate the present invention, the following examples are listed, but it does not limit the scope of the invention defined by the appended claims.
[0019] Example 1
[0020] a. Weigh 13 g of 25% tetrapropylammonium hydroxide solution, 109 mg of aluminum isopropoxide and 15 g of ultrapure water, and mix and stir for 30 min.
[0021] b. Add 0.14 g of tris(ethylenediamine)ruthenium chloride, and continue to stir at room temperature for 30 min.
[0022] c. After mixing 1 g of NaOH and 13 g of tetraethoxysilane and treating at 90 °C for 2 h, add it to the above mixed system, continue to stir at room temperature for 6 h, and stand for aging for 12 h.
[0023] d. Transfer the solution in c to a hydrothermal autoclave and perform hydrothermal treatment at 120 °C for 48 h.
[0024] e. Separate the solid in d, wash it three times with ultrapure water and ethanol respectively, and then dry it at 60 °C overnight.
[0025] f. Calcinate the solid in step e at 550 °C for 8 h to obtain the Ru@Y zeolite catalyst with a Ru loading of 1 wt%. The AC-HAADF-STEM results show that Ru is dispersed in the zeolite channels at the single-atom scale.
[0026] Example 2
[0027] Except for using tris(ethylenediamine)rhodium(III) chloride to replace tris(ethylenediamine)ruthenium(II) chloride in step b, it is prepared by the same method as described in Example 1 to obtain the Rh@Y zeolite catalyst with a Rh loading of 1 wt%. The AC-HAADF-STEM results show that Rh is dispersed in the zeolite channels at the single-atom scale.
[0028] Example 3
[0029] Except for using 0.09 g of tris(ethylenediamine)platinum(II) chloride to replace tris(ethylenediamine)ruthenium(II) chloride in step b, it is prepared by the same method as described in Example 1 to obtain the Pt@Y zeolite catalyst with a Pt loading of 1 wt%. The AC-HAADF-STEM results show that Pt is dispersed in the zeolite channels at the single-atom scale.
[0030] Example 4
[0031] Except for using tris(ethylenediamine)palladium(II) chloride to replace tris(ethylenediamine)ruthenium(II) chloride in step b, it is prepared by the same method as described in Example 1 to obtain the Pd@Y zeolite catalyst with a Pd loading of 1 wt%. The AC-HAADF-STEM results show that Pd is dispersed in the zeolite channels at the single-atom scale.
[0032] Example 5
[0033] Sieve the Ru@Y zeolite catalyst prepared in Example 1 into 20-40 mesh, load it into the reaction tube, and carry out the selective hydrogenation ring-opening reaction of decalin at 300 °C, 5 MPa, for 3 h -1 , under the reaction conditions of a hydrogen-oil ratio of 500, the conversion rate of decalin is 95.8%, and the ring-opening selectivity is 89.2%. The product is C10 alkanes.
[0034] Example 6
[0035] Sieve the Ru@Y zeolite catalyst prepared in Example 1 into 20-40 mesh, load it into the reaction tube, and carry out the selective hydrogenation ring-opening reaction of decalin at 220 °C, 5 MPa, for 3 h -1, under the reaction conditions with a hydrogen-oil ratio of 500, the conversion rate of decalin is 65.8%, and the ring-opening selectivity is 92.1%.
[0036] Example 7
[0037] The Ru@Y zeolite catalyst prepared in Example 1 was sieved into 20-40 mesh and loaded into a reaction tube for the selective hydrogenation ring-opening reaction of decalin. At 350 °C, 5 MPa, and 3 h -1 , under the reaction conditions with a hydrogen-oil ratio of 500, the conversion rate of decalin is 98.9%, and the ring-opening selectivity is 59.7%.
[0038] Example 8
[0039] The Ru@Y zeolite catalyst prepared in Example 1 was sieved into 20-40 mesh and loaded into a reaction tube for the selective hydrogenation ring-opening reaction of decalin. At 300 °C, 1 MPa, and 3 h -1 , under the reaction conditions with a hydrogen-oil ratio of 500, the conversion rate of decalin is 85.5%, and the ring-opening selectivity is 85.0%.
[0040] Example 9
[0041] The Ru@Y zeolite catalyst prepared in Example 1 was sieved into 20-40 mesh and loaded into a reaction tube for the selective hydrogenation ring-opening reaction of decalin. At 300 °C, 7 MPa, and 3 h -1 , under the reaction conditions with a hydrogen-oil ratio of 500, the conversion rate of decalin is 95.5%, and the ring-opening selectivity is 88.1%.
[0042] Example 10
[0043] The Ru@Y zeolite catalyst prepared in Example 1 was sieved into 20-40 mesh and loaded into a reaction tube for the selective hydrogenation ring-opening reaction of decalin. At 300 °C, 5 MPa, and 0.5 h -1 , under the reaction conditions with a hydrogen-oil ratio of 500, the conversion rate of decalin is 97.8%, and the ring-opening selectivity is 69.2%.
[0044] Example 11
[0045] The Ru@Y zeolite catalyst prepared in Example 1 was sieved into 20-40 mesh and loaded into a reaction tube for the selective hydrogenation ring-opening reaction of decalin. At 300 °C, 5 MPa, and 5 h -1 , under the reaction conditions with a hydrogen-oil ratio of 500, the conversion rate of decalin is 86.8%, and the ring-opening selectivity is 90.3%.
[0046] Example 12
[0047] The process and conditions are the same as those in Example 5, except that the catalyst is changed to the Rh@Y zeolite catalyst prepared in Example 2. The conversion rate of decalin is 91.5%, and the ring-opening selectivity is 88.3%.
[0048] Example 13
[0049] The process and conditions are the same as those in Example 5, except that the catalyst is changed to the Pt@Y zeolite catalyst prepared in Example 3. The conversion rate of decalin is 94.5%, and the ring-opening selectivity is 90.1%.
[0050] Example 14
[0051] The process and conditions are the same as those in Example 5, except that the catalyst is changed to the Pd@Y zeolite catalyst prepared in Example 4. The conversion rate of decalin is 92.4%, and the ring-opening selectivity is 89.3%.
[0052] Comparative Example 1
[0053] The process and conditions are the same as those in Example 5, except that the catalyst is changed to a 1 wt% Ru / Y zeolite catalyst (prepared by the incipient wetness impregnation method). The conversion rate of decalin is 62.4%, and the ring-opening selectivity is 79.8%.
[0054] Comparative Example 2
[0055] The process and conditions are the same as those in Example 5, except that the catalyst is changed to a 1 wt% Ru / ZSM5 zeolite catalyst (prepared by the incipient wetness impregnation method). The conversion rate of decalin is 50.4%, and the ring-opening selectivity is 69.8%.
[0056] As described above, these are only the preferred embodiments of the present invention. Therefore, the scope of implementation of the present invention cannot be limited thereby. That is, equivalent changes made according to the scope of the present invention patent and the content of the specification should still fall within the scope covered by the present invention.
Claims
1. A preparation method of a catalyst for selective hydrogenation ring-opening of cycloalkanes, characterized in that: The catalyst is composed of M@Y zeolite, where M is one or more of Ru, Rh, Pt, and Pd, and the mass percentage is: 0.1% - 5%, preferably 0.5% - 3%; The specific process includes: (1) Mix the aluminum source, water, and alkali source and stir evenly; (2) Add the noble metal precursor; (3) After adding the alkali-treated silicon source, continue to stir the mixed system for 2 - 12 hours, and then stand for aging for 6 - 24 hours; (4) Transfer the solution obtained in step (3) to a hydrothermal autoclave and perform hydrothermal treatment for 12 - 72 hours; (5) Filter out the solid substance obtained in step (4), wash it 1 - 6 times with water and ethanol in sequence, and then dry it; (6) Calcinate the solid obtained in step (5) to obtain the M@Y zeolite catalyst.
2. According to the preparation method described in claim 1, wherein: In step (1), the aluminum source is one or two of aluminum isopropoxide and sodium aluminate, the alkali source is tetrapropylammonium hydroxide, and the mass ratio of the aluminum source, alkali source, and water is 1:2 - 30:100 - 400, preferably 1:3 - 18:200 - 350; In step (2), the noble metal precursor is one or more of tris(ethylenediamine)ruthenium chloride, tris(ethylenediamine)rhodium trichloride, ethylenediamineplatinum chloride, and ethylenediaminepalladium chloride.
3. According to the preparation method described in claim 1, wherein: In step (3), the alkali is one or more of NaOH, KOH, and ammonia water with a mass concentration of 1 - 28%, and the mass ratio of the alkali to the silicon source is 0.01 - 15, preferably 1 - 13. The alkali treatment process is heat treatment, the temperature is 90 - 110°C for 2 - 10 h, and the silicon source is one or more of tetraethoxysilane, sodium silicate, and sodium aluminosilicate; The molar mass ratio of the silicon source to the aluminum source is 50 - 150:1, preferably 60 - 120:
1.
4. According to the preparation method described in claim 1, wherein: In step (4), the hydrothermal treatment temperature is 80 - 220°C, preferably 90 - 200°C; In step (6), the calcination temperature is 300 - 600°C, preferably 350 - 550°C; the calcination time is 2 - 12 hours, preferably 3 - 10 hours.
5. A catalyst for selective hydrogenation ring opening of cycloalkanes prepared by the preparation method described in any one of claims 1 - 4.
6. The selective hydrogenation ring-opening catalyst for cycloalkanes according to claim 5, characterized in that: The catalyst is composed of M@Y zeolite, where M is atomically dispersed in the supercages (pores and cavities) of the Y zeolite, and the Y zeolite coats the atomically dispersed noble metal M.
7. An application of the M@Y zeolite catalyst described in claim 5 or 6 in the catalytic selective hydrogenation ring opening of cycloalkanes.
8. The application according to claim 7, characterized in that: The cycloalkane is a cycloalkane with 3 - 20 carbon atoms.
9. According to the application described in claim 7 or 8, wherein: The reaction temperature is 220 - 300 °C (preferably 230 - 280 °C), the pressure is 1 - 7 MPa (preferably 2 - 6 MPa), and the liquid hourly space velocity is 0.5 - 5 h -1 (preferably 1 - 4 h -1 ), and the hydrogen - to - oil volume ratio is 200 - 20000 (preferably 300 - 1500).