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CN-121988412-A - In-situ regeneration method of heavy aromatic hydrogenation catalyst

CN121988412ACN 121988412 ACN121988412 ACN 121988412ACN-121988412-A

Abstract

The present application provides an in situ regeneration process for a heavy aromatics hydrogenation catalyst, wherein the heavy aromatics hydrogenation catalyst has been used to catalyze hydrogen and fresh liquid phase heavy aromatics in a reaction apparatus for a selective hydrogenation reaction to produce hydrogenated heavy aromatics products, the process comprising maintaining the heavy aromatics hydrogenation catalyst in the reaction apparatus, stopping fresh liquid phase heavy aromatics feed, and recycling the hydrogenated heavy aromatics products to the reaction apparatus, such that the heavy aromatics hydrogenation catalyst is regenerated in the presence of hydrogen and hydrogenated heavy aromatics products. The method provided by the application utilizes the circulation of aromatic hydrocarbon products to carry out in-situ regeneration on the heavy aromatic hydrocarbon hydrogenation catalyst with reduced catalytic activity, does not need to disassemble the catalyst, does not need to use extra solvent, and has low regeneration temperature and good performance of the regenerated catalyst.

Inventors

  • WANG DEJU
  • SHANG CHENGCHENG
  • REN JIE
  • WANG NING
  • ZHU ZHIYAN
  • QI SHENGDONG

Assignees

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

Dates

Publication Date
20260508
Application Date
20241108

Claims (10)

  1. 1. An in situ regeneration process for a heavy aromatics hydrogenation catalyst that has been used to catalyze a selective hydrogenation reaction of hydrogen and fresh liquid phase heavy aromatics in a reaction apparatus to produce a hydrogenated heavy aromatics product, the process comprising the steps of: And (3) keeping the heavy aromatic hydrogenation catalyst in the reaction device, stopping fresh liquid-phase heavy aromatic feeding, and recycling the hydrogenated heavy aromatic product to the reaction device, so that the heavy aromatic hydrogenation catalyst is regenerated in the presence of hydrogen and the hydrogenated heavy aromatic product.
  2. 2. The in situ regeneration process according to claim 1, wherein the volumetric space velocity of the heavy aromatics product over heavy aromatics hydrogenation catalyst is 0.1h -1 -20h -1 , preferably 1h -1 -10h -1 , more preferably 4h -1 -8h -1 .
  3. 3. The in situ regeneration process according to claim 1 or 2, wherein the hydrogenated heavy aromatic product has an initial boiling point of 160 ℃ to 190 ℃ and a final boiling point of 340 ℃ to 360 ℃, and/or In the heavy hydrogenation aromatic hydrocarbon product, the mass content of C 8 and the following components is 0.1-10wt%, the mass content of C 10 -C 14 naphthalene is 0.1-30wt%, the mass content of C 10 -C 14 tetrahydronaphthalene is 0.1-70wt%, the mass content of C 9 -C 14 aromatic hydrocarbon is 30-60deg.C, the mass content of decahydronaphthalene is 0.05-5wt%, and the mass content of C 14 and the above components is 0.5-10wt%.
  4. 4. An in situ regeneration process according to any one of claims 1 to 3, wherein the hydrogen has a volumetric space velocity of 10h -1 -600h -1 , preferably 50h -1 -500h -1 , more preferably 100h -1 -400h -1 .
  5. 5. The in situ regeneration process according to any one of claims 1-4, wherein the regeneration is performed at a pressure of 0.5MPaG-5MPaG, preferably 1MPaG-4 MPaG.
  6. 6. The in situ regeneration process according to any one of claims 1 to 5, wherein the regeneration is performed at a temperature of 50 ℃ to 179 ℃, preferably 80 ℃ to 160 ℃.
  7. 7. The in situ regeneration process according to any one of claims 1 to 6, wherein the hydrogenation reaction is a reaction for converting heavy aromatics-selective hydrodenaphthalene into tetrahydronaphthalene, Preferably, the conversion of naphthalene is less than 92%, such as less than 90%, and the fresh liquid phase heavy aromatics feed is stopped to regenerate the heavy aromatics hydrogenation catalyst, and/or In the regeneration process, when the conversion rate of naphthalene is higher than 90%, stopping regeneration, and introducing fresh liquid heavy aromatic hydrocarbon to react, wherein the regeneration duration is preferably 1-36 h, and preferably 4-24 h.
  8. 8. The in situ regeneration process according to any one of claims 1 to 7, wherein the fresh liquid heavy aromatic hydrocarbon has an initial boiling point of 160 ℃ to 190 ℃ and a final boiling point of 340 ℃ to 360 ℃ and/or comprises C 6 -C 20 aromatic hydrocarbon, naphthene, unsaturated olefin, saturated olefin, wherein the mass content of C 8 -C 12 aromatic hydrocarbon is 80% -99.9%, Preferably, in the fresh liquid-phase heavy aromatic hydrocarbon, the mass content of C 8 and the following components is 0.1-10wt%, the mass content of C 10 -C 14 naphthalene is 0.1-70wt%, the mass content of C 10 -C 14 tetrahydronaphthalene is 0.01-5wt%, the mass content of C 9 -C 12 aromatic hydrocarbon is 35-60deg.wt%, the mass content of decahydronaphthalene is 0.1-2wt%, and the mass content of C 12 and above components is 0.5-10wt%.
  9. 9. The in situ regeneration process according to any one of claims 1 to 8, wherein the heavy aromatics hydrogenation catalyst comprises a support and an active component supported on the support, said active component being selected from one or more of metals of groups VIB, VIIB, VIII, IB and IIB, preferably from one or more of metals of groups VIB and VIII, more preferably from one or more of Ni, pd, W or Mo, and/or The carrier is selected from one or more of alumina, silica and zirconia.
  10. 10. A process for the selective hydrogenation of heavy aromatic hydrocarbons in the liquid phase comprising the steps of: s1, in a reaction device, in the presence of a heavy aromatic hydrogenation catalyst, carrying out selective hydrogenation reaction on fresh liquid-phase heavy aromatic hydrocarbon and hydrogen to generate a hydrogenated heavy aromatic hydrocarbon product, and obtaining an inactivated heavy aromatic hydrocarbon hydrogenation catalyst; s2, regenerating the deactivated heavy aromatics hydrogenation catalyst in a reaction device by adopting the in-situ regeneration method as claimed in any one of claims 1 to 9.

Description

In-situ regeneration method of heavy aromatic hydrogenation catalyst Technical Field The application belongs to the field of chemical industry, and particularly relates to an in-situ regeneration method of a heavy aromatic hydrogenation catalyst. Background The heavy aromatics comprise fractions rich in macromolecular aromatics, which are produced by reforming devices, steam cracking devices, aromatics combination and other oil refining chemical devices. At present, an aromatic hydrocarbon combination device can treat and utilize C 9 and light C 10 components in heavy aromatic hydrocarbon reforming to produce light aromatic hydrocarbon (BTX aromatic hydrocarbon), but a large amount of heavy aromatic hydrocarbon with more than C 10 is still difficult to utilize, and the heavy aromatic hydrocarbon accounts for about 4% -5% of reforming processing capacity. In recent years, along with the large-scale construction and energy expansion transformation of refining devices, the yield of C 10 + heavy aromatics is also continuously increased. The naphthalene fused ring compound and the polymethylbenzene in the C 10 + reforming heavy aromatic fraction have higher content, and are potential raw materials for producing BTX aromatic by converting C 10 + heavy aromatic. Because the polycyclic aromatic hydrocarbon such as naphthalene and alkyl naphthalene in the raw materials is easy to be adsorbed in micropores of the molecular sieve catalyst and carbon deposition is generated at high temperature, the coking and deactivation of the catalyst are easy to be caused, and the yield of the product of converting heavy aromatic hydrocarbon into BTX is reduced. If the polycyclic aromatic hydrocarbon of C 10 + heavy aromatic hydrocarbon is converted into monocyclic aromatic hydrocarbon by first hydrotreating, then the reaction conversion such as dealkylation and transalkylation is carried out, the maximization of the BTX light aromatic hydrocarbon yield can be realized. On the one hand, the method eliminates the adverse effect of the polycyclic aromatic hydrocarbon on the aromatic hydrocarbon conversion process, and on the other hand, the polycyclic aromatic hydrocarbon is converted into the monocyclic aromatic hydrocarbon by hydrogenation, and the monocyclic aromatic hydrocarbon and the heavy alkylbenzene serving as raw materials for preparing the BTX aromatic hydrocarbon are used as raw materials, so that the raw material sources are expanded. The selective hydrogenation catalyst is the core of the technology for converting the polycyclic aromatic hydrocarbon of C 10 + heavy aromatic hydrocarbon into the monocyclic aromatic hydrocarbon. Selective hydrogenation catalysts generally consist of two parts, an active metal providing a hydrogenation function, such as cobalt, nickel, palladium, platinum, etc., and a support, such as amorphous silica alumina, etc., sometimes with small amounts of other materials added to optimize catalyst performance. Patent CN105772034A, CN111068728A, CN116060082A, CN117797804a et al both disclose catalysts for the preparation of high value added downstream products by hydrogenation of polycyclic aromatic hydrocarbons. However, due to the characteristics of heavy aromatic hydrocarbon raw materials, the activity of the catalyst is gradually reduced in carbon deposition during long-term operation, after the condition occurs, a temperature-increasing method is often adopted to keep the activity of the catalyst, and when the bearing capacity of equipment and the performance of the catalyst are insufficient to ensure that the temperature is further increased, the operation is stopped, and the catalyst is regenerated. The existing regeneration method mainly comprises an atmosphere regeneration method, an oxygen regeneration method and a washing regeneration method, but the existing technology adopts the out-of-device regeneration technology to overcome the defect that the existing technology is more overwhelming, the in-device regeneration is less, the in-device regeneration mainly adopts gas stripping regeneration or burning-reduction regeneration, and no report of catalyst regeneration by adopting reaction materials is seen. CN114682265A discloses a regenerated liquid of deactivated Co-Mo type hydrogenation catalyst and a regenerating method, in which after the catalyst is discharged, the deactivated hydrogenation catalyst is regenerated by using the regenerated liquid, and the discharging increases material abrasion and increases loading and unloading costs. CN112206721a discloses a fixed bed reactor and a method for regenerating hydrogenation catalyst, which mainly uses oxygen-containing gas flow to remove colloid deposited on the surface of catalyst, but the cold gas consumption of gas treatment is large, and a large amount of nitrogen is needed to control the reaction temperature, which increases the investment and consumption of the device. CN117643836a discloses a hydrogenation catalyst regeneration de