Search

CN-117282460-B - Gas phase cracking catalyst, preparation method and application thereof

CN117282460BCN 117282460 BCN117282460 BCN 117282460BCN-117282460-B

Abstract

The invention relates to the field of catalysts, and discloses a gas phase cracking catalyst, a preparation method and application thereof. The catalyst comprises, by weight, 1.5-20 parts of an active component and 80-98.5 parts of a carrier, wherein the active component element is selected from one or more of IIB, IIIA, IVA and VA, the active component exists in the form of simple substance and/or oxide, and the carrier is selected from one or more of ZSM-5 type, Y type and X type molecular sieves. The catalyst disclosed by the invention is applied to the reaction of synthesizing 2-methoxypropene by gas phase pyrolysis of 2, 2-dimethoxypropane, has the characteristics of high catalytic activity, few byproducts and high stability, and has a good application prospect.

Inventors

  • SHANG ZHOU
  • ZHANG WEI
  • XU YONGZHI
  • ZHENG TAO
  • PANG LIHUA

Assignees

  • 宁夏天新药业有限公司

Dates

Publication Date
20260505
Application Date
20230801

Claims (13)

  1. 1. The application of the gas phase cracking catalyst in the reaction of synthesizing 2-methoxypropene by gas phase cracking of 2, 2-dimethoxypropane comprises, by weight, 1.5-20 parts of active components and 80-98.5 parts of carrier; the active component elements are two of In and Sb, or the active component elements are Sn; The carrier is selected from Zn-ZSM-5 molecular sieve.
  2. 2. The process according to claim 1, wherein the catalyst comprises, in parts by weight, 2-12 parts of active ingredient and 88-98 parts of carrier.
  3. 3. The use according to claim 1, wherein, The active component element is selected from In and Sb.
  4. 4. The use according to claim 1, wherein, The zinc oxide content in the molecular sieve is 2-40% of the total weight of the molecular sieve.
  5. 5. The use according to any one of claims 1 to 4, the preparation method of the gas phase cracking catalyst comprising: 1) Obtaining a carrier; 2) Immersing and contacting the active component source solution with a carrier; 3) Drying and calcining.
  6. 6. The use according to claim 5, wherein, The drying conditions in step 3) include a temperature of 60-120deg.C for a time of 5-20 h, and/or The calcination conditions in step 3) include a temperature of 400-800 ℃ and a time of 2-10 h.
  7. 7. The use according to claim 5, wherein, The active component source is selected from two of indium nitrate and antimony acetate, or the active component source is selected from tin acetate.
  8. 8. The use according to claim 7, wherein, The active component source is indium nitrate and antimony acetate, and the mol ratio of the indium nitrate to the antimony acetate is (0.5-2): 1.
  9. 9. The use according to claim 5, wherein the preparation of the carrier in step 1) comprises: a) Fully mixing zinc salt and H-ZSM-5 molecular sieve powder; b) Grinding and calcining.
  10. 10. The use according to claim 9, wherein in step b), The grinding conditions include a time of 1-5h, and/or The calcination conditions include a temperature of 400-800 ℃ and a time of 2-10 h.
  11. 11. The use according to claim 9, wherein, The H-ZSM-5 molecular sieve has a silica-alumina ratio of 20 to 500, and/or The specific surface area of the H-ZSM-5 molecular sieve is 300-650m 2 /g, and/or The zinc salt is selected from one or more of zinc chloride and zinc acetate, and/or The dosage mass ratio of the zinc salt to the H-ZSM-5 molecular sieve is 1 (2-15).
  12. 12. The use according to claim 11, wherein, The zinc salt is selected from zinc acetate.
  13. 13. The use according to claim 1, wherein, The reaction conditions include 160-250 deg.c, catalyst loading of 10-60g and 2, 2-dimethoxy propane flow rate of 0.5-4.0 mL/min.

Description

Gas phase cracking catalyst, preparation method and application thereof Technical Field The invention relates to the field of catalysts, in particular to a gas phase cracking catalyst and a preparation method and application thereof. Background 2-Methoxypropene is an important pharmaceutical intermediate, and is widely used in the synthesis process of clarithromycin, pseudoionone, vitamins, carotenes and the like. Because of the great demand, the research and development of a simple, efficient and large-scale industrialized 2-methoxy propylene synthesis method is particularly important. Currently, the synthetic methods of 2-methoxypropene mainly include direct synthesis methods and liquid-phase or gas-phase cracking methods. The direct synthesis method for obtaining 2-methoxypropene by nucleophilic addition of methanol and unsaturated hydrocarbon has the defects of difficult obtaining of reaction raw materials, violent and uncontrollable reaction process, large corrosion of required catalyst to production equipment and the like although the steps are simple. The cracking method is to remove one molecule of methanol from 2, 2-dimethoxy propane under the action of a catalyst at a higher temperature to prepare the product 2-methoxy propylene. Among them, the liquid phase cracking method using inorganic or organic acids as homogeneous catalyst requires the use of solvents and anhydrides which are costly and also troublesome in post-reaction treatment. The conversion rate and selectivity of the gas phase cracking method are high, and the composition of the reacted cracking liquid is relatively simple and easy to separate, so that the method is a synthetic method with more cost and feasibility advantages. The development of catalyst systems with higher catalytic activity and stability is one of the key issues of gas phase cracking processes. Catalysts suitable for this reaction include phosphates of some metals, acidic ceramics, heteropolyacids, cationic resins, molecular sieves, and the like. The existing patent US5767325 adopts self-made ZSM-5 as a gas phase cracking catalyst to prepare 2-methoxypropene, the reaction temperature is 280-340 ℃, and the product yield is 83.3%. Also CN1660742a compares different types of catalysts, where the acidic molecular sieves are less active than the heteropolyacids and acidic ceramics. Therefore, the molecular sieve catalyst is modified, so that the molecular sieve catalyst has higher reaction performance and stability, and is a feasible idea for designing and developing a catalyst for synthesizing 2-methoxypropene by gas phase pyrolysis. Disclosure of Invention The invention aims to solve the problems of poor reaction performance and poor stability of the existing gas phase cracking catalyst, and provides a gas phase cracking catalyst, a preparation method and application thereof. In order to achieve the aim, the invention provides a gas phase cracking catalyst which comprises, by weight, 1.5-20 parts of active components and 80-98.5 parts of carriers, wherein the active component elements are selected from one or more of IIB group, IIIA group, IVA group and VA group, the active components exist in the form of simple substances and/or oxides, and the carriers are selected from one or more of ZSM-5 type, Y type and X type molecular sieves. In a second aspect, the present invention provides a process for the preparation of the catalyst according to the invention, which comprises: 1) Obtaining a carrier; 2) Immersing and contacting the active component source solution with a carrier; 3) Drying and calcining. The third aspect of the invention provides application of the catalyst in the reaction of synthesizing 2-methoxypropene by 2, 2-dimethoxypropane gas-phase pyrolysis, wherein the reaction conditions preferably comprise a reaction temperature of 160-250 ℃, a catalyst loading of 10-60g and a2, 2-dimethoxypropane gas flow rate of 0.5-4.0mL/min. The catalyst of the invention is applied to a gas phase pyrolysis reaction, such as a reaction for synthesizing 2-methoxypropene by gas phase pyrolysis of 2, 2-dimethoxypropane, and has the characteristics of high conversion rate, high selectivity and good stability. Detailed Description The endpoints and any values of the ranges disclosed herein are not limited to the precise range or value, and are understood to encompass values approaching those ranges or values. For numerical ranges, one or more new numerical ranges may be found between the endpoints of each range, between the endpoint of each range and the individual point value, and between the individual point value, in combination with each other, and are to be considered as specifically disclosed herein. The invention provides a gas phase cracking catalyst which comprises, by weight, 1.5-20 parts of an active component and 80-98.5 parts of a carrier, wherein the active component element is selected from one or more of IIB, IIIA, IVA and VA, the active component exists in the fo