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CN-120624059-B - Catalytic slurry oil hydrotreating method

CN120624059BCN 120624059 BCN120624059 BCN 120624059BCN-120624059-B

Abstract

The invention discloses a catalytic cracking slurry oil hydrotreating method. The hydrogenation process of the fixed bed is adopted, and the hydrogenation process comprises the steps of sequentially contacting catalytic cracking slurry oil with a hydrogenation protecting agent, a hydrogenation transition catalyst and a hydrogenation desulfurization catalyst in the presence of hydrogen to carry out hydrogenation reaction to obtain hydrogenation generated oil, wherein the hydrogenation protecting agent comprises an alumina carrier with the most probable pore diameter of 40-100 nm, molybdenum oxide and cobalt oxide, the hydrogenation transition catalyst comprises an alumina carrier containing an auxiliary agent, moO 3 and CoO, the carrier has bimodal pore diameter distribution, the smaller pore diameter is distributed in a concentrated manner of 10-40 nm, and the larger pore diameter is distributed in a concentrated manner of 150-400 nm. The method can eliminate the diffusion resistance of macromolecules on the surface of the catalyst during the hydrogenation of the catalytic cracking slurry, improve and contain more sediments such as carbon deposit, prolong the running period of the device, simultaneously be beneficial to the reaction such as hydrodesulfurization, improve the content of tricyclic and tetracyclic aromatic hydrocarbons in the hydrogenated oil, and is a high-quality raw material for producing needle coke.

Inventors

  • LIU WENJIE
  • ZHANG QINGJUN
  • SUI BAOKUAN
  • MU FUJUN
  • YUAN SHENGHUA

Assignees

  • 中国石油化工股份有限公司
  • 中石化（大连）石油化工研究院有限公司

Dates

Publication Date
20260505
Application Date
20240312

Claims (20)

  1. 1. A hydrogenation treatment method of catalytic cracking slurry oil adopts a fixed bed hydrogenation process, comprising the steps of sequentially contacting a catalytic cracking slurry oil raw material with a hydrogenation protective agent, a hydrogenation transition catalyst and a hydrogenation desulfurization catalyst in the presence of hydrogen to carry out hydrogenation reaction to obtain hydrogenation generated oil; The hydrogenation protective agent comprises a carrier and hydrogenation active metals, wherein an alumina carrier is adopted, the hydrogenation active metals comprise molybdenum oxide and cobalt oxide, the alumina carrier has the characteristics that pore volume occupied by pore channels from the most probable pore diameter of 40-100 nm (the most probable pore diameter of-30) nm to the most probable pore diameter of +30) nm accounts for more than 75% of the total pore volume, the pore volume of the alumina carrier is 1.00-1.40 cm 3 /g, and the specific surface area is 120-180 m 2 /g; The hydrogenation transition catalyst comprises an alumina carrier containing an auxiliary agent, moO 3 and CoO, wherein the carrier has bimodal pore size distribution, smaller pore sizes are intensively distributed at 10-40 nm, pore spaces with the pore sizes of 10-40 nm account for 20% -40% of the total pore volume, larger pore sizes are intensively distributed at 150-400 nm, pore spaces with the pore sizes of 150-400 nm account for 30% -50% of the total pore volume, and in the hydrogenation transition catalyst, the pore volume of the carrier is 0.95-1.35 cm 3 /g, and the specific surface area is 110-175 m 2 /g.
  2. 2. The method according to claim 1, wherein the hydrogenation protecting agent is characterized in that the alumina carrier has a characteristic that pore volume of pore channels from 50-70 nm (most probable pore diameter-30) nm to (most probable pore diameter +30) nm is 75-90% of total pore volume.
  3. 3. The method according to claim 1, wherein the mass content of MoO 3 is 2.0% -7.0% and the mass content of CoO is 0.3% -1.7% based on the mass of the hydrogenation protecting agent; and/or, based on the mass of the hydrogenation transition catalyst, the content of MoO 3 is 4.0% -10.0%, and the content of CoO is 0.8% -2.5%.
  4. 4. The method according to claim 1, wherein in the hydrogenation protecting agent, the pore volume of the alumina carrier is 1.10-1.30 cm 3 /g, and the specific surface area is 130-170 m 2 /g; And/or in the hydrogenation transition catalyst, the pore volume of the carrier is 1.00-1.25 cm 3 /g, and the specific surface area is 130-170 m 2 /g.
  5. 5. The process of claim 1, wherein the shape of the hydrogenation protecting agent is tetraimpeller or tetraleaf grass, and/or the shape of the hydrogenation transition catalyst is tetraleaf grass.
  6. 6. The method according to claim 1, wherein in the hydrogenation transition catalyst, in the alumina carrier containing the auxiliary agent, the auxiliary agent is one or more of fluorine, phosphorus, silicon or boron, and the content of the auxiliary agent in terms of elements is 0.2% -10% of the total mass of the alumina in the carrier.
  7. 7. The method according to claim 6, wherein in the hydrogenation transition catalyst, the auxiliary agent is silicon in the alumina carrier containing the auxiliary agent, and the content of the auxiliary agent in terms of elements is 1% -6% of the total mass of the alumina in the carrier.
  8. 8. The method according to claim 1, wherein the method for preparing the hydrogenation protecting agent comprises the steps of: a) Mixing the first aluminum source, the second aluminum source and the third aluminum source with water to obtain slurry, and grinding the slurry; b) Adding purified water into the slurry obtained in the step a) to stir; c) Adding a modifier, a pH value regulator and an optional dispersing agent into the material obtained in the step b) to obtain mixed slurry, and performing hydrothermal treatment on the mixed slurry; d) Drying the material obtained in the step c) to obtain alumina dry gel; e) Mixing the alumina gel obtained in the step d) with a binder, molding, drying and roasting to obtain a carrier; f) Impregnating the carrier obtained in the step e) with impregnating solution containing molybdenum and cobalt, and drying and roasting to obtain the hydrogenation protective agent.
  9. 9. The method according to claim 8, wherein in the step a), the first aluminum source is alumina trihydrate, the second aluminum source is alumina gel, the water content of the second aluminum source is less than 35% by mass, and the third aluminum source is an aluminum-containing salt compound.
  10. 10. The method of claim 9, wherein in step a) the second aluminum source is alumina gel is alumina monohydrate and the third aluminum source is at least one of aluminum nitrate, aluminum chloride, aluminum sulfate, and sodium metaaluminate.
  11. 11. The method according to claim 9, wherein in step a), the mass ratio of the first aluminum source, the second aluminum source and the third aluminum source is 30-66:33-60:1-10.
  12. 12. The method according to claim 9, wherein in the step a), the water is added in an amount of 100% -150% of the total mass of the first aluminum source, the second aluminum source and the third aluminum source.
  13. 13. The method according to claim 9, wherein in step a), the slurry is milled to a particle size of 4 to 20 μm, calculated as median particle diameter D50.
  14. 14. The method according to claim 9, wherein in step b), the slurry obtained in step a) is stirred by adding purified water so that the total mass of the first aluminum source, the second aluminum source and the third aluminum source is 10% -20% of the mass content of the slurry.
  15. 15. The method according to claim 8 or 9, wherein in step c), the pH of the mixed slurry is controlled to be 8.5-12.0.
  16. 16. The method according to claim 15, wherein in the step c), the dispersing agent is a nonionic surfactant with an HLB value of 10-20, and/or the modifying agent is at least one of sodium hexametaphosphate, sodium tripolyphosphate, disodium edetate, sodium gluconate, and sodium tartrate.
  17. 17. The method of claim 16, wherein in step c) the dispersant is at least one of tween-80, polyoxyethylene lauryl ether, and polyoxyethylene methyl glucose ether.
  18. 18. The method according to claim 15, wherein in the step c), the modifier is added in an amount of 0.01% -6% by mass of the material obtained in the step b), and/or the dispersant is added in an amount of 10% or less by mass of the material obtained in the step b).
  19. 19. The method according to claim 18, wherein in step c), the dispersant is added in an amount of 0.01% -10% by mass of the material obtained in step b).
  20. 20. The method according to claim 15, wherein in the step C), the hydrothermal treatment is performed at 220-280 ℃ for 5-12 hours.

Description

Catalytic slurry oil hydrotreating method Technical Field The invention belongs to the technical field of hydrogenation, and particularly relates to a catalytic slurry oil hydrotreating method. Background With the continuous inferior and heavy petroleum resources, the market demands for diversified and light petrochemical products are increasing, and the processing of inferior and heavy crude oil becomes an important subject for world refining enterprises. The catalytic cracking technology is one of three main processes of heavy oil deep processing, is a main process technology for lightening raw materials, and has strong adaptability to the raw materials. At present, partial catalytic cracking device can directly process atmospheric residuum or blend partial vacuum residuum, thereby bringing about the problems of poor distribution of catalytic cracking products and the like. In order to improve the processing capacity of the device, reduce the energy consumption and increase the light products, the external oil slurry throwing is a good solution, and a great amount of byproduct catalytic cracking oil slurry is generated. As a low added value product produced in the catalytic cracking process, the catalytic cracking slurry oil has the characteristics of high density, high carbon residue value, high viscosity, high aromatic content and the like, contains residual catalyst particles and coke, and has high processing and utilization difficulty, so how to process and utilize the catalytic cracking slurry oil becomes a key problem to be solved urgently by refineries. The catalytic cracking slurry oil is rich in aromatic hydrocarbon and is an ideal raw material for preparing high-end carbon-based materials such as needle coke. The needle coke has the characteristics of high crystallinity, high strength, high graphitization, low thermal expansion, low ablation and the like, and is mainly used for ultrahigh-power graphite electrodes and lithium ion battery cathode materials. As a feedstock for the production of needle coke, catalytic cracking slurry oils are generally required to have low sulfur, low nitrogen, low ash, high aromatics content, and particularly high tricyclic and tetracyclic aromatics content. The catalytic cracking slurry oil has high density, high carbon residue value, high viscosity, high aromatic content, residual catalyst particles and coke, and is difficult to use. The prior high-quality low-sulfur slurry oil has very tight resources, the sulfur content of the low-quality slurry oil is higher (1.0 wt% -2.0 wt%) and the needle coke product has strict requirements on the sulfur content (no more than 0.5 wt%) while the problem of over high aromatic hydrocarbon loss exists when the conventional residual oil hydrogenation series catalyst is adopted for treatment. At present, the research on a hydrogenation catalyst special for catalytic cracking slurry oil is less, so that the development of a catalyst suitable for catalytic cracking slurry oil hydrogenation is significant. CN103013567a discloses a process for producing needle coke feedstock from catalytic cracking slurry oil. The method is characterized in that a protection zone and a hydrogenation reaction zone are arranged, wherein an adsorbent capable of adsorbing catalytic cracking catalyst powder is filled in the protection zone, a hydrogenation protecting agent, a hydrodemetallization agent and a hydrodesulfurization agent are sequentially filled in the hydrogenation reaction zone according to the flow direction of a reactant flow, catalytic cracking slurry oil firstly enters the protection zone to adsorb most of catalytic cracking catalyst powder, then enters a heating furnace after being mixed with hydrogen, and enters the hydrogenation reaction zone for hydrogenation treatment reaction. The hydrogenation protecting agent is Raschig ring-shaped and is a conventional residual oil hydrogenation protecting agent, the hydrogenation demetallizing agent comprises an alumina carrier, molybdenum and/or tungsten and nickel and/or cobalt loaded on the carrier, the pore volume of the carrier is 70% -98% of the total pore volume, the pore diameter of the carrier is 100-200 angstrom (10-20 nm), the hydrogenation protecting agent comprises a carrier, molybdenum and/or tungsten and nickel and/or cobalt loaded on the carrier, the carrier is alumina and optional silicon oxide, and the pore volume of the carrier is 75% -98% of the total pore volume, the pore diameter of the carrier is 60-100 angstrom (6-10 nm). The hydrodemetallization agent and the hydrodesulphurization agent are conventional residual oil hydrogenation series catalysts, and can be used for hydrogenating catalytic cracking slurry oil, but for the catalytic cracking slurry oil, the metal content is less, the metal sediment is less, the pore diameter of a carrier is smaller, the pore volume of macropores is less, and in the hydrogenation reaction process, adsorption and reaction of macromolecu