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CN-121972213-A - Ferrierite molecular sieve catalyst and preparation method and application thereof

CN121972213ACN 121972213 ACN121972213 ACN 121972213ACN-121972213-A

Abstract

The invention provides a ferrierite molecular sieve catalyst and a preparation method and application thereof, and the ferrierite molecular sieve catalyst comprises the following steps of (1) mixing a first raw material system comprising an alkali source, an aluminum source, a silicon source, a composite template agent and water, performing a first reaction to obtain a first material, (2) performing hydrothermal treatment on the first material, then sequentially performing filtration, first drying and first roasting to obtain a second material, (3) performing ion exchange on the second material and a second raw material system comprising an ammonium salt aqueous solution to obtain a third material, and (4) mixing the third material and a third raw material system comprising a binder and a solvent, and performing extrusion molding, second drying and second roasting to obtain the ferrierite molecular sieve catalyst. The ferrierite molecular sieve catalyst provided by the invention has the advantages of high superposition reaction selectivity, high cracking catalytic efficiency and low cost.

Inventors

  • REN KUN
  • WANG XIAOSHENG

Assignees

  • 中国石油大学(北京)

Dates

Publication Date
20260505
Application Date
20260107

Claims (10)

  1. 1. A method for preparing a ferrierite molecular sieve catalyst, which is characterized by comprising the following steps: (1) Mixing a first raw material system comprising an alkali source, an aluminum source, a silicon source, a composite template agent and water, and performing a first reaction to obtain a first material; (2) Carrying out hydrothermal treatment on the first material, and then sequentially carrying out filtration, first drying and first roasting to obtain a second material; (3) Ion exchanging the second material and a second raw material system comprising an aqueous solution of an ammonium salt to obtain a third material; (4) And mixing the third material with a third raw material system comprising a binder and a solvent, and performing extrusion molding, secondary drying and secondary roasting to obtain the ferrierite molecular sieve catalyst.
  2. 2. The method of preparing a ferrierite molecular sieve catalyst according to claim 1, wherein the alkali source comprises one or more of sodium hydroxide, potassium hydroxide; And/or the aluminum source comprises one or more of aluminum sulfate, aluminum nitrate and sodium metaaluminate; and/or the silicon source comprises one or more of alkaline silica sol, fumed silica and sodium silicate; And/or the molar ratio of the aluminum element of the aluminum source to the silicon element of the silicon source is 1 (10-100); And/or the molar ratio of the alkali source to the silicon element of the silicon source is (0.06-0.40) 1 in terms of sodium hydroxide.
  3. 3. The preparation method of the ferrierite molecular sieve catalyst according to claim 1 or 2, wherein the composite template agent comprises a small molecular template agent, an acyl amino acid and triethanolamine, wherein the small molecular template agent comprises one or more of ethylenediamine, n-butylamine, pyrrolidone, tetrahydrofuran and pyridine; preferably, the acyl amino acid comprises one or more of N-acetyl-L-phenylalanine, N-acetyl-L-tyrosine, N-acetyl-L-tryptophan, N-acetyl-L-histidine.
  4. 4. A ferrierite molecular sieve catalyst, characterized in that the ferrierite molecular sieve catalyst is prepared according to the method of preparing a ferrierite molecular sieve catalyst according to any one of claims 1 to 3.
  5. 5. A method for preparing propylene and butylene, which is characterized by comprising the following steps: The propylene and the butylene are prepared by taking mixed light alkane and alkene as raw material gases under the catalysis of the ferrierite molecular sieve catalyst of claim 4, wherein the raw material gases comprise alkane with carbon atoms of 1-4 and alkene with carbon atoms of 2-4.
  6. 6. The method for producing propylene and butene according to claim 5 wherein the ferrierite molecular sieve catalyst comprises a first ferrierite molecular sieve catalyst and a second ferrierite molecular sieve catalyst, wherein the molar ratio of elemental silicon to elemental aluminum in the first ferrierite molecular sieve catalyst is (40-100): 1, and the molar ratio of elemental silicon to elemental aluminum in the second ferrierite molecular sieve catalyst is (10-40): 1.
  7. 7. The method for preparing propylene and butylene according to claim 6, wherein the process for preparing propylene and butylene by using mixed light alkane and alkene as raw material gas under the catalysis of ferrierite molecular sieve catalyst specifically comprises: under the action of the first ferrierite molecular sieve catalyst, carrying out superposition reaction on the raw material gas, and then carrying out gas-liquid separation to obtain an alkane gas-phase material and a liquid-phase material; and carrying out gasification pretreatment on the liquid-phase material to obtain a gasified material, and then carrying out cracking isomerization reaction on the gasified material under the action of the second ferrierite molecular sieve catalyst to obtain the propylene and the butene.
  8. 8. The method for producing propylene and butene according to claim 7, wherein the temperature of the polymerization reaction is 100 ℃ to 250 ℃; and/or the temperature of the cracking isomerization reaction is 300-600 ℃.
  9. 9. The method for producing propylene and butene according to claim 7 or 8, wherein in the course of the polymerization reaction, the gas hourly space velocity of the raw material gas is 500 -1 ~2000h -1 and the pressure is 1.0MPa to 5.0 MPa.
  10. 10. The process for the production of propylene and butene according to any of claims 7 to 9 characterized in that during the cracking isomerization reaction the gas hourly space velocity of the gasified material is 500 -1 ~1000h -1 .

Description

Ferrierite molecular sieve catalyst and preparation method and application thereof Technical Field The invention relates to the technical field of molecular sieve catalysts and preparation thereof, in particular to a ferrierite molecular sieve catalyst and a preparation method and application thereof. Background During the refining of oils, atmospheric and vacuum and catalytic cracking processes produce products of partially mixed lower olefins, (e.g., methane, ethane, ethylene, propane, propylene, butane, butene, etc.), which are typically sold directly as liquefied gas (LPG) or used for low value added fuel applications, resulting in wasted resources. At present, high-value utilization methods such as dehydrogenation and alkylation are available for alkanes with higher purity, and high-value utilization methods such as superposition, alkylation, polymerization, isomerization and etherification are available for alkenes with higher purity. In the mixed low-carbon alkane olefin, the physicochemical properties of alkane and olefin are greatly different (such as boiling point, polarity, reactivity and the like), but the separation process has the following challenges that the separation difficulty is high, the physical properties of alkane and olefin are similar, the traditional rectification method needs multistage separation, the process is complex, the energy consumption is high, the added value of the product is low, the mixture is directly used as fuel, the high value of the mixture as a chemical raw material cannot be fully exerted (such as propylene and isobutene can be used for producing high-added value products such as polypropylene, methyl tert-butyl ether (MTBE) and the like), the raw material complexity is high, the components in the mixture are various, and the directional conversion and separation of the components are realized through an efficient reaction-separation coupling process. Conventional separation methods for lower olefins generally employ rectification separation methods. CN114832414a discloses a device for refining LPG to produce high purity alkane by multi-tower coupling rectification and a process thereof, wherein the multi-tower coupling rectification is needed in the separation process, and the separation of mixed alkane and alkene in LPG is realized by a step-by-step separation mode. CN212881106U discloses a system for separating mixed light hydrocarbons, and also adopts a multistage rectification method to separate mixed light hydrocarbons. The method can effectively separate and stage-utilize the light alkane and the alkene, and maximize the utilization of the alkane and the alkene. However, the method of rectification separation has the advantages of higher energy consumption, longer flow, and higher construction, maintenance and operation costs. In order to solve the problems, a catalyst is conventionally used for separating and catalyzing low-carbon alkane, but the traditional catalyst has insufficient selectivity on the superposition reaction and is easy to generate byproducts, so that the subsequent separation process is complex, the isomerization efficiency of the cracking catalyst on propylene and ethylene is low, the high conversion rate is difficult to realize, and the industrialized application of the cracking catalyst is limited due to the fact that part of the catalyst depends on noble metal or the preparation process is complex. Therefore, development of a ferrierite molecular sieve catalyst which has high polymerization selectivity, high cracking catalytic efficiency and low cost has become a research hotspot in the field. Disclosure of Invention The invention provides a ferrierite molecular sieve catalyst, a preparation method and application thereof, and the ferrierite molecular sieve catalyst is suitable for separating low-carbon olefin, has high polymerization selectivity, high cracking catalytic efficiency and low cost. The invention provides a preparation method of a ferrierite molecular sieve catalyst, which comprises the following steps of (1) mixing a first raw material system comprising an alkali source, an aluminum source, a silicon source, a composite template agent and water, performing a first reaction to obtain a first material, (2) performing hydrothermal treatment on the first material, sequentially performing filtration, first drying and first roasting to obtain a second material, (3) performing ion exchange on the second material and a second raw material system comprising an ammonium salt aqueous solution to obtain a third material, and (4) mixing the third material with a third raw material system comprising a binder and a solvent, and performing extrusion molding, second drying and second roasting to obtain the ferrierite molecular sieve catalyst. Optionally, the alkali source comprises one or more of sodium hydroxide and potassium hydroxide, and/or the aluminum source comprises one or more of aluminum sulfate, aluminum nitrate and sodium