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CN-118847169-B - Hydrodesulfurization and demetallization catalyst and preparation method thereof

CN118847169BCN 118847169 BCN118847169 BCN 118847169BCN-118847169-B

Abstract

The invention discloses a hydrodesulfurization and demetallization catalyst and a preparation method thereof, wherein the catalyst comprises an alumina carrier containing spherical cavities, hydrogenation active metal molybdenum, nickel, cobalt and auxiliary phosphorus, wherein flaky alumina grows in situ in the spherical cavities and on the outer surface of the carrier, the filling rate of the flaky alumina in the spherical cavities is 40-80%, the coverage rate of the flaky alumina on the outer surface of the carrier is 50-80%, the size of the spherical cavities is 1-5 mu m, the grain size of the flaky alumina is 100-500nm, the content of active metal MoO 3 at the spherical cavities is 16.5-21.5 wt%, the content of NiO is 4.0-6.0 wt%, and the content of CoO is 1.5-3.5 wt%. The catalyst ensures stronger impurity capacity of the surface pore canal structure by controlling the coverage rate of the surface flaky alumina, the filling rate and the metal content in the cavity, and is more suitable for the residual oil hydrodesulfurization and hydrodemetallization process.

Inventors

  • XUE YANG
  • JI HONGHAI
  • WANG SHAOJUN
  • GAO JINGSHAN

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
20230426

Claims (15)

  1. 1. A hydrodesulfurization and demetallization catalyst is characterized by comprising an alumina carrier containing spherical cavities, hydrogenation active metal molybdenum, nickel, cobalt and auxiliary phosphorus, wherein flaky alumina grows in situ in the spherical cavities and on the outer surface of the carrier, the filling rate of the flaky alumina in the spherical cavities is 40% -80%, the coverage rate of the flaky alumina on the outer surface of the carrier is 50% -80%, the size of the spherical cavities is 1-5 mu m, the grain size of the flaky alumina is 100-500nm, the content of active metal MoO 3 at the spherical cavities is 16.5% -21.5% by weight, the content of NiO is 4.0% -6.0% by weight, the content of CoO is 1.5% -3.5% by weight, the preparation method of the hydrodesulfurization and demetallization catalyst comprises the steps of (1) impregnating micron-sized spherical active carbon with phosphorus-containing solution and molybdenum-cobalt-nickel impregnating solution to obtain modified micron-sized spherical active carbon, (2) mixing the modified micron-sized spherical active carbon, pseudo-boehmite and water into slurry, carrying out solid-liquid separation, carrying out drying and kneading, carrying out kneading, forming, the solid-phase material into the solid-phase material, carrying out drying, and carrying out fluid-phase separation, and carrying out fluid-phase drying, and 3-phase fluid drying, 3-phase material drying, 3.5% and 3.5% of the carrier, and 3-phase material, and 3-phase carrier, and 3-phase drying, 3-phase material, 3-phase oxidation catalyst, 3 and 3-phase catalyst, and 3 drying.
  2. 2. The catalyst according to claim 1, wherein the MoO 3 is 13.0wt% to 18.5wt%, the NiO is 3.5wt% to 5.0wt%, the CoO is 0.1wt% to 0.5wt%, the phosphorus is 0.2wt% to 0.8wt% in terms of elemental phosphorus, and the alumina carrier is 75.2wt% to 83.2wt% based on the total weight of the catalyst.
  3. 3. The catalyst according to claim 1, wherein the alumina support has pores of 30-80nm in the form of stacked flaky alumina in micron-sized spherical cavities.
  4. 4. The catalyst according to claim 1, wherein the flaky alumina forms pores of 30 to 150nm on the outer surface of the carrier.
  5. 5. A preparation method of the hydrodesulfurization and demetallization catalyst according to any one of claims 1-4 is characterized by comprising the following steps of (1) impregnating micron-sized spherical active carbon with a phosphorus-containing solution and molybdenum-cobalt-nickel impregnating solution to obtain modified micron-sized spherical active carbon, (2) mixing the modified micron-sized spherical active carbon, pseudo-boehmite and water into slurry, carrying out solid-liquid separation, drying a solid-phase material, carrying out kneading, forming, drying and roasting to obtain a first alumina carrier, (3) immersing the first alumina carrier into an epoxypropane aqueous solution for sealing and heat treatment, carrying out solid-liquid separation on the treated material, drying and roasting the solid-phase material to obtain a second alumina carrier, and (4) carrying out drying and roasting on the second alumina carrier with the molybdenum-nickel impregnating solution to obtain the catalyst.
  6. 6. The method according to claim 5, wherein the phosphorus-containing solution in the step (1) is an aqueous solution of a phosphate salt, the phosphate salt is one or more of ammonium phosphate, diammonium phosphate and monoammonium phosphate, the concentration of the aqueous solution of the phosphate salt is 1.5% -3.5% in terms of the element P, and the dipping time is 0.5-4 hours.
  7. 7. The method of claim 5, wherein the molybdenum-cobalt-nickel impregnating solution in the step (1) has a molybdenum content of 3.5-7.5g/100mL in terms of molybdenum oxide, a cobalt content of 1.0-2.5g/100mL in terms of cobalt oxide, and a nickel content of 0.6-1.5g/100mL in terms of nickel oxide, and the impregnating time is 0.5-4 hours.
  8. 8. The method of claim 5, wherein the mass ratio of the modified micron spherical active carbon to the pseudo-boehmite in the step (2) is 1:9-1:19, and the liquid-solid mass ratio of the slurry is 5:1-10:1.
  9. 9. The method according to claim 5, wherein the drying temperature in the step (2) is 100-160 ℃, the drying time is 4-10 hours, the baking temperature is 450-700 ℃, and the baking time is 4-6 hours, and the baking is performed in an oxygen-containing atmosphere.
  10. 10. The method of claim 5, wherein the concentration of the aqueous solution of propylene oxide in the step (3) is 2.5-12% by mass, and the mass ratio of the amount of the aqueous solution of propylene oxide to the precursor of the alumina carrier is 3:1-10:1.
  11. 11. The method according to claim 5, wherein the sealing heat treatment in the step (3) is performed for 1 to 4 hours at 60 to 100 ℃ and then 8 to 12 hours at 110 to 180 ℃.
  12. 12. The method according to claim 5, wherein the drying temperature in the step (3) is 100-160 ℃, the drying time is 2-8 hours, the baking temperature is 500-750 ℃, and the baking time is 4-6 hours, and the baking is performed in an oxygen-containing atmosphere.
  13. 13. The method of claim 5, wherein the molybdenum-nickel immersion liquid of the step (4) has a Mo content of 10-20g/100mL in terms of metal oxide and a Ni content of 2.5-5g/100mL in terms of metal oxide.
  14. 14. The method according to claim 5, wherein the drying condition in the step (4) is a drying temperature of 100-180 ℃ and a drying time of 1-10 hours, and the baking condition is a baking temperature of 400-500 ℃ and a baking time of 2-8 hours.
  15. 15. Use of the hydrodesulfurization and demetallization catalyst according to any one of claims 1-4 in a process for hydrotreating inferior heavy oil.

Description

Hydrodesulfurization and demetallization catalyst and preparation method thereof Technical Field The invention belongs to the field of catalyst preparation, and particularly relates to a hydrodesulfurization and demetallization catalyst and a preparation method thereof. Background The fixed bed heavy oil hydrotreating technology has the advantages of mature technology, simple operation, good product quality and the like, and is the most commonly used heavy oil hydrotreating technology in the industry at present. The main purpose of the fixed bed heavy oil hydroprocessing process is to remove a large amount of impurities contained in the residuum feedstock, such as sulfur, nitrogen, metals, asphaltenes, etc., and to provide feedstock to the catalytic cracking unit. The main reactions of the process include hydrodemetallization, hydrodesulphurisation, hydrodenitrogenation, aromatic saturation, hydrocarbon hydrocracking, etc. For heavy distillate oil, the raw materials contain a large number of reactant molecules with complex structure, large molecular diameter and rich heteroatom number, and the catalyst activity is continuously reduced due to the influence of metal deposition and carbon deposition in the reaction process, so that the catalyst is required to have good reaction activity, excellent diffusion performance and scale-holding capacity. CN104646008a discloses a hydrodesulphurization demetallization catalyst for inferior heavy oil and a preparation method thereof. The catalyst takes alumina as a carrier, takes VIII and VIB elements, particularly Ni-Mo as active components, has a catalyst pore volume of 0.61-0.70mL/g, a specific surface area of 155-200m 2/g and an average pore diameter of 13.0-18.0nm, and the average pore diameter gradually increases from the center to the outer surface along the radial direction of the catalyst particles. The catalyst is prepared through treating the shaped and roasted carrier particle with acid solution with continuously increased concentration, and has improved scale holding capacity. CN111822011a discloses a support, catalyst for hydrodesulfurization and a method for preparing the same. The carrier is an alumina carrier containing auxiliary agents, and comprises main body alumina and rod-shaped alumina, wherein the main body alumina is alumina with micron-sized pore channels, at least part of the rod-shaped alumina is distributed on the outer surface of the main body alumina and in the micron-sized pore channels, the auxiliary agents phosphorus and/or boron are distributed in the micron-sized pore channels, and the auxiliary agents titanium are distributed on the surface of the rod-shaped alumina on the outer surface of the carrier. The preparation method of the carrier comprises the steps of adsorbing a solution containing auxiliary agent phosphorus and/or boron by a physical pore-expanding agent, kneading with pseudo-boehmite to form, drying and roasting to obtain a carrier intermediate, immersing the carrier intermediate in an ammonium bicarbonate solution, carrying out sealing heat treatment and drying, spraying the solution containing auxiliary agent titanium on the outer surface of a material, and drying and roasting to obtain the alumina carrier. The surface of the catalyst prepared by the method is in a rod-shaped structure, but the firmness of the combination of the rod-shaped alumina growing on the surface and the main alumina needs to be further improved. Disclosure of Invention Aiming at the defects in the prior art, the invention provides a hydrodesulfurization and demetallization catalyst and a preparation method thereof, and the catalyst ensures stronger impurity capacity of a surface pore structure by controlling the coverage rate of surface flaky alumina and the filling rate and metal content in a cavity, and is more suitable for the hydrodesulfurization and hydrodemetallization process of residual oil. The hydrodesulfurization and demetallization catalyst comprises an alumina carrier containing spherical cavities, hydrogenation active metal molybdenum, nickel, cobalt and auxiliary agent phosphorus, wherein flaky alumina grows in situ in the spherical cavities and on the outer surface of the carrier, the filling rate of the flaky alumina in the spherical cavities is 40-80%, the coverage rate of the flaky alumina on the outer surface of the carrier is 50-80%, the size of the spherical cavities is 1-5 mu m, the grain size of the flaky alumina is 100-500nm, the content of active metal MoO 3 at the spherical cavities is 16.5-21.5 wt%, the content of NiO is 4.0-6.0 wt% and the content of CoO is 1.5-3.5 wt%. In the hydrodesulfurization and demetallization catalyst, 13.0 to 18.5 weight percent of MoO 3, 3.5 to 5.0 weight percent of NiO, 0.1 to 0.5 weight percent of CoO, 0.2 to 0.8 weight percent of phosphorus calculated as elemental phosphorus and 75.2 to 83.2 weight percent of alumina carrier are calculated by the total weight of the catalyst. In the hyd