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CN-121988402-A - Macroporous alumina and preparation method and application thereof

CN121988402ACN 121988402 ACN121988402 ACN 121988402ACN-121988402-A

Abstract

The invention discloses macroporous alumina and a preparation method and application thereof, wherein the preparation method comprises the following steps of S1, mixing isobutylene-maleic anhydride copolymer powder with ammonia water for ammonolysis reaction to obtain a solution, S2, mixing the solution in the step S1, hydrated alumina powder, kaolin powder and cellulose to obtain a mixture, S3, mixing the mixture in the step S3 with an acidic solution and water, molding, drying and roasting to obtain the macroporous alumina. The preparation method provided by the invention has the advantages of simple preparation process, environment-friendly preparation process and low cost. The large Kong Zhayou hydrogenation protective agent carrier formed by the invention has larger pore volume, contains a large proportion of coherent and smooth pore structures which are larger than 500nm, is uniformly distributed, is very favorable for the diffusion of macromolecular heterocyclic compounds in residual oil into the protective agent, and is very favorable for accommodating a large amount of metal impurities.

Inventors

  • SONG JUNNAN
  • LIU YINDONG
  • CHENG TAO
  • CUI RUILI
  • ZHAO YUANSHENG
  • ZHANG TAO
  • YU SHUANGLIN
  • ZHANG ZHIGUO
  • ZHANG CHUNGUANG
  • WANG LUHAI

Assignees

  • 中国石油天然气股份有限公司

Dates

Publication Date
20260508
Application Date
20241108

Claims (10)

  1. 1. The preparation method of the macroporous alumina is characterized by comprising the following steps: s1, mixing isobutene-maleic anhydride copolymer powder with ammonia water for ammonolysis reaction to obtain a solution; S2, mixing the solution obtained in the step S1, hydrated alumina powder, kaolin powder and cellulose to obtain a mixture; And S3, mixing the mixture obtained in the step S3 with an acidic solution and water, forming, drying and roasting to obtain the macroporous alumina.
  2. 2. The method for preparing macroporous alumina according to claim 1, wherein the number average molecular weight of the isobutylene-maleic anhydride copolymer is 200000 to 400000.
  3. 3. The method for preparing macroporous alumina according to claim 1, wherein the ammonia water is 20-100% of the weight of the isobutylene-maleic anhydride copolymer, and the concentration of the ammonia water is 20-40w%.
  4. 4. The method for preparing macroporous alumina according to claim 1, wherein the weight ratio of the hydrated alumina to the kaolin is 9:1-5:5, and the weight ratio of the cellulose to the total weight of the hydrated alumina and the kaolin is 5:100-15:100.
  5. 5. The method for preparing macroporous alumina according to claim 1, wherein the amount of the isobutylene-maleic anhydride copolymer added is 5-30w% of the total weight of the hydrated alumina and kaolin.
  6. 6. The method for preparing macroporous alumina according to claim 1, wherein the hydrated alumina is one or more selected from gibbsite, boehmite, pseudo-boehmite and amorphous aluminum hydroxide, the kaolin is calcined kaolin, the mesh number of the powder is not less than 800 mesh, and the cellulose is one or more selected from methylcellulose, ethylcellulose, hydroxypropyl methylcellulose and hydroxyethyl methylcellulose.
  7. 7. The method for preparing macroporous alumina according to claim 1, wherein the addition amount of the acidic solution is 4-15w% of the total weight of the hydrated alumina and the kaolin, and the addition amount of the deionized water is 80-120w% of the total weight of the hydrated alumina and the kaolin.
  8. 8. The method for preparing macroporous alumina according to claim 1, wherein the drying temperature in the step S3 is 100-120 ℃, the drying time is 2-6 hours, the roasting temperature is 1100-1300 ℃, and the roasting time is 4-8 hours.
  9. 9. The macroporous alumina prepared by the preparation method of any one of claims 1 to 8, wherein the mercury intrusion pore volume is 0.4-1.0ml/g, and the pore volume with the pore diameter of >500nm accounts for 10% -45% of the total pore volume, and the strength is >20N/mm.
  10. 10. Use of the macroporous alumina prepared by the preparation method of any one of claims 1 to 8 or the macroporous alumina of claim 9 in a fixed bed residuum hydrogenation protectant or an upflow residuum hydrogenation protectant.

Description

Macroporous alumina and preparation method and application thereof Technical Field The invention belongs to the technical field of catalyst carriers, and particularly relates to macroporous alumina, a preparation method and application thereof. Background Currently, as worldwide petroleum resources become increasingly heavier and inferior, there is an urgent need to develop clean and efficient heavy oil processing techniques. Hydrogenation is the most efficient heavy and residuum feedstock processing technique. Through hydrogenation, most of metal impurities and sulfur are removed, the carbon residue value is reduced, the quality of heavy oil is improved, and the possibility is provided for further efficient cleaning processing of the heavy oil. The combination of heavy oil and residual oil hydrotreating and heavy oil catalytic cracking technology can not only maximally convert residual oil with low utilization value and easy environmental pollution, greatly improve the light oil yield, but also obtain clean oil with high added value and superior quality. The technology combination becomes a core technology for improving economic benefit of sulfur-containing crude oil processing oil refining enterprises. The deposition of Na, ca, ni, V and other metals in heavy oil on the hydrogenation catalyst can cause permanent poisoning, and is an important factor to be considered in the heavy oil hydrogenation process. The active protecting agent and hydrodemetallization catalyst in the protecting agent are key technologies in the heavy oil hydrotreating process, and mainly serve to remove most of Ni, V and other metal impurities in the raw materials, protect downstream desulfurization (HDS) and denitrification (HDN) catalysts, and have certain desulfurization capability. The above two types of catalysts are required to have not only good metal removal ability but also high metal impurity accommodation ability. Because most of the metal impurities in the residual oil exist in colloid and asphaltene, the colloid and asphaltene are the types with the largest molecular weight, the most complex structure and the strongest polarity in petroleum components, and have larger diffusion resistance. The demetallization agent is limited by the mass transfer and diffusion efficiency of the carrier, is easy to cause orifice blockage, has serious uneven deposition distribution of the removed impurities, and has limited metal holding capacity. All of the above causes serious waste of the internal space of the catalyst, and the efficiency of the single catalyst cannot be fully exerted. Therefore, the two catalysts have larger pore volume, pore diameter and good pore channel permeability, so as to be beneficial to diffusion, reaction and deposition of macromolecular substances such as asphaltene and the like containing metal impurities in the residual oil raw materials. One of the solutions is to use macroporous alumina carrier, and in the reaction process, macropores with pore diameters above 100nm provide channels for the diffusion of macromolecular reaction substances, so as to promote the diffusion and deposition of impurities to the internal pore canal of the catalyst, thereby leading the catalyst to have high demetallization activity and high impurity capacity. In order to obtain alumina support materials having a macroporous structure, researchers have used pore-enlarging agents, hydrothermal treatments, and the like to obtain alumina having a macroporous structure. The related literature for synthesizing macroporous alumina materials by a pore-expanding agent method is more, and the method can be divided into a hard pore-expanding agent method and a soft pore-expanding agent method according to different pore-expanding agent types. The hard pore-expanding agent method represented by activated carbon can obtain better macroporous alumina, and US19820384626 discloses that carbon black is used as a pore-expanding agent, so that macroporous alumina with pore diameters distributed at 15-300 nm can be obtained, but the macroporous alumina with concentrated pore diameters is difficult to prepare due to non-uniform particle diameter distribution of the carbon black. CN201410347665.X discloses a preparation method of large pore volume and high strength alumina, wherein pore-enlarging agents such as polyacrylamide, polyvinyl alcohol, alkyl cellulose, sesbania powder, starch and the like are added to obtain an alumina carrier containing large pores, the using amount of the pore-enlarging agents accounts for 10% -30% of that of the alumina, but the specific pore diameter range is not disclosed. Although the hard pore-expanding agent method can obtain a better macroporous alumina carrier, the dosage of the pore-expanding agent is preferably more than 20 percent, so that the processing cost is greatly improved, and the decomposition of a large amount of pore-expanding agent does not meet the development requirements of low carbon and environm