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CN-117816225-B - Preparation method of catalyst containing molecular sieve

CN117816225BCN 117816225 BCN117816225 BCN 117816225BCN-117816225-B

Abstract

A preparation method of a catalyst containing a molecular sieve is characterized by comprising the following steps of (1) carrying out contact reaction on alumina or a precursor of the alumina and organic amine to obtain a solution containing a tetra-coordinated aluminum species, (2) mixing the aluminosilicate molecular sieve with the solution containing the tetra-coordinated aluminum species in the step (1) and then carrying out hydrothermal reaction in a crystallization kettle, filtering, washing and drying a crystallized product to obtain a first molecular sieve, (3) carrying out mixed heating treatment on the first molecular sieve in the step (2) and an acid solution, filtering, washing and drying the product to obtain a second molecular sieve, (4) roasting the second molecular sieve in the step (3) to obtain a modified hydrogen aluminosilicate molecular sieve, (5) mixing the modified hydrogen aluminosilicate molecular sieve with a binder or the precursor thereof, and optionally added acid liquor, an auxiliary agent and water to form, drying and roasting.

Inventors

  • LIN MENG
  • ZHANG CHENGXI
  • LI YONGXIANG
  • ZHOU SHUNLI
  • REN KUI
  • SHU XINGTIAN

Assignees

  • 中国石油化工股份有限公司
  • 中石化石油化工科学研究院有限公司

Dates

Publication Date
20260505
Application Date
20220927

Claims (20)

  1. 1. A process for preparing the catalyst containing molecular sieve includes such steps as contact reaction of alumina or its precursor with organic amine to obtain the solution containing tetra-coordinated Al, mixing the molecular sieve with the solution containing tetra-coordinated Al, hydrothermal reaction in crystallizing reactor, filtering, washing and drying to obtain the first molecular sieve, mixing the first molecular sieve with an acid solution, heating, filtering, washing and drying to obtain the second molecular sieve, and calcining to obtain the modified molecular sieve with the characteristics of (a), (B) and (c) that the A value is 4.0-6.0 and B value is not less than 1.4 The said Wherein Q 4 、Q 3 、Q 2 、Q 1 and Q 0 respectively correspond to peak areas of five distinguishable spectrum peaks appearing in a MAS NMR 29 Si spectrogram of the molecular sieve, correspond to SiO 4 tetrahedral structures of the species, sequentially correspond to Si (4 Si, 0 Al), si (3 Si, 1 Al), si (2 Si, 2 Al), si (1 Si, 3 Al)) and Si (0 Si, 4 Al) resonance peaks from high field to low field, (b) the surface silicon aluminum molar ratio is 0.9-2.0, the surface element distribution is determined by X-ray photoelectron spectroscopy analysis, (c) the bulk silicon aluminum molar ratio is 2.0-4.0, the bulk element distribution is determined by X-ray fluorescence spectroscopy analysis, and (5) the modified hydrogen aluminosilicate molecular sieve, the binder or a precursor thereof, acid liquor, an auxiliary agent and water which are optionally added are mixed for molding, dried and baked.
  2. 2. The method according to claim 1, wherein the precursor of alumina in step (1) is selected from one or more of pseudo-boehmite, aluminum hydroxide and alumina sol.
  3. 3. The method of claim 1, wherein the organic amine of step (1) is selected from one or more of tetramethylammonium hydroxide, tetraethylammonium hydroxide, and tetrapropylammonium hydroxide.
  4. 4. The process according to claim 1, wherein the mass ratio of alumina or a precursor of alumina to organic amine in step (1) is 0.01-2:1, wherein the precursor of alumina is based on alumina.
  5. 5. The process according to claim 4, wherein the mass ratio of alumina or a precursor of alumina to organic amine in step (1) is 0.04 to 1:1.
  6. 6. The process according to claim 1, wherein the contacting reaction in step (1) is carried out at a temperature of 60 to 150℃for a period of 1 to 10 h.
  7. 7. The process according to claim 6, wherein the contacting reaction in step (1) is carried out at a temperature of 100 to 150℃for a period of 2 to 6h ℃.
  8. 8. The method of claim 1, wherein the solution comprising tetra-coordinated aluminum species in step (1) has a concentration of 0.4 to 20 wt% by weight of aluminum.
  9. 9. The process according to claim 1, wherein the hydrogen aluminosilicate molecular sieve in step (2) is selected from one of a hydrogen type Y-type molecular sieve, an X-type molecular sieve, a beta-type molecular sieve, a MOR-type molecular sieve and a ZSM-5-type molecular sieve.
  10. 10. The process according to claim 1, wherein the aluminosilicate molecular sieve in the hydrogen form of step (2) has a silica-alumina ratio of 5 to 100.
  11. 11. The process according to claim 10, wherein the aluminosilicate molecular sieve in the hydrogen form of step (2) has a silica-alumina ratio of 5 to 20.
  12. 12. The process according to claim 1, wherein the mass ratio of the hydrogen aluminosilicate molecular sieve to the solution containing tetra-coordinated aluminum species in step (2) is from 100 to 1:1, wherein the hydrogen aluminosilicate molecular sieve is on a dry basis and the solution containing tetra-coordinated aluminum species is on aluminum.
  13. 13. The process according to claim 12, wherein the mass ratio of the hydrogen aluminosilicate molecular sieve of step (2) to the solution containing tetra-coordinated aluminium species is from 25 to 5:1.
  14. 14. The process according to claim 1, wherein the hydrothermal reaction in step (2) is carried out at a temperature of 100 to 150℃for a period of 1 to 20 h.
  15. 15. The method of claim 1, wherein the acid solution of step (3) is selected from one or more of hydrochloric acid, nitric acid, lactic acid, oxalic acid, hydrofluoric acid, and fluosilicic acid.
  16. 16. The method of claim 1, wherein the acid solution in step (3) is present in a concentration of 0.1 to 20 wt%.
  17. 17. The method of claim 16, wherein the acid solution in step (3) is present in a concentration of 0.5 to 5 wt%.
  18. 18. The method of claim 1, wherein the mass ratio of the acid solution to the first molecular sieve in step (3) is 2-20:1.
  19. 19. The method of claim 18, wherein the mass ratio of the acid solution to the first molecular sieve in step (3) is 3-8:1.
  20. 20. The method according to claim 1, wherein the heating treatment in the step (3) is carried out at a temperature of 40 to 95℃for a time of 0.1 to 10h ℃.

Description

Preparation method of catalyst containing molecular sieve Technical Field The invention relates to the field of preparation of molecular sieve catalysts, in particular to a preparation method of a catalyst containing a molecular sieve, and a catalyst prepared by the method and application. Background The alkylation reaction of isobutane and butene is an important process for producing high-octane gasoline components in petroleum refining industry, and the alkylated oil, as an ideal high-octane gasoline blending component, has the characteristics of high octane number, low sensitivity, lei Defa low vapor pressure, low sulfur content and no olefin and aromatic hydrocarbon. The existing industrial alkylate production process mainly comprises a sulfuric acid method and a hydrofluoric acid method, but the safety and environmental protection pressure of alkylate production enterprises are increased due to the corrosion and toxicity of sulfuric acid and hydrofluoric acid and the harm of waste acid emission in the process flow to the environment. The solid acid alkylation process has the advantages of environmental protection and good stability, and is considered as the most promising reaction process. The core of the solid acid alkylation process is the development of solid acid catalysts with excellent performance, and the solid acid alkylation catalysts are mainly divided into four types, namely metal halides, solid superacids, supported heteropolyacids and molecular sieves at present. The molecular sieve catalyst has large specific surface area, more acid sites, adjustable acidity, good thermal stability and shape selective catalysis, and is widely applied in petrochemical fields. However, the problem of rapid catalyst deactivation still exists, so that the industrial process of the solid acid alkylation technology of the molecular sieve catalyst is influenced. CN109865532a discloses a preparation method and application of a solid acid catalyzed carbon tetraalkylation catalyst. In-situ introducing a certain amount of heteropolyacid compound (HPA) and metal components such as Pt and Fe into the preparation process of the hierarchical pore ZSM-5 molecular sieve, so that the heteropolyacid compound and Pt and Fe nano particles grow on the surface of the ZSM-5 molecular sieve pore channel with the hierarchical pores in situ. The preparation method is easy to amplify, can be applied to the field of catalysis of the carbon tetraalkylacid, and has good industrial application prospect. Wherein, heteropolyacid is introduced to supplement the catalyst, and the alkylation performance can be further improved by adopting a molecular sieve with higher acidity as an active center. CN104891525A discloses a preparation method of a strong acid high stability mesoporous molecular sieve. The preparation method comprises the steps of firstly synthesizing a Y-type molecular sieve precursor, then assembling the Y-type molecular sieve precursor under an acidic condition by adopting a seed crystal method to obtain a first-step crystallization product, adjusting the pH value of the first-step crystallization product, and performing second-step crystallization to obtain the product. The prepared molecular sieve has strong hydrothermal stability, strong acidity and low cost, and has better catalytic cracking performance of heavy oil as a component of the catalyst. However, the synthesis steps are complicated, and the acid amount still needs to be further increased for the acid catalytic reaction. Disclosure of Invention The invention aims to meet the high acidity requirement of the existing molecular sieve catalyst applied to the alkylation reaction of solid acid, and provides a preparation method of the catalyst containing the molecular sieve. In order to achieve the above purpose, the first aspect of the invention provides a preparation method of a catalyst containing molecular sieve, which is characterized by comprising the following steps of (1) carrying out contact reaction on alumina or a precursor of the alumina and organic amine to obtain a solution containing tetra-coordinated aluminum species, (2) mixing an aluminosilicate molecular sieve with the solution containing tetra-coordinated aluminum species in the step (1) and then carrying out hydrothermal reaction in a crystallization kettle, filtering, washing and drying a crystallized product to obtain a first molecular sieve, (3) carrying out mixed heating treatment on the first molecular sieve in the step (2) and an acid solution, filtering, washing and drying the product to obtain a second molecular sieve, (4) roasting the second molecular sieve in the step (3) to obtain a modified hydrogen aluminosilicate molecular sieve, (5) mixing the modified hydrogen aluminosilicate molecular sieve with a binder or the precursor thereof, an acid solution, an auxiliary agent and water, forming, drying and roasting. In the invention, the binder is at least one of alumina, zirconia, silica or