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CN-121988328-A - Shaped catalyst, preparation method and application thereof

CN121988328ACN 121988328 ACN121988328 ACN 121988328ACN-121988328-A

Abstract

The invention relates to the technical field of catalysts, and discloses a molded catalyst, a preparation method and application thereof, wherein the molded catalyst comprises a lanthanum-containing substance and cordierite, the composition of the cordierite comprises Mg and Fe, and the molar ratio of Mg to Fe in the cordierite is more than 1. The formed catalyst has higher mechanical strength and can meet the requirements of equipment on the catalyst in the industrial amplifying process. The shaped catalyst of the invention can improve the conversion of methane and the hydrocarbon selectivity of two or more carbon atoms when being used for oxidative coupling of methane.

Inventors

  • WU JIEHUA
  • BAI JIE
  • LI WEI
  • WANG HUANRU
  • SUN KANG

Assignees

  • 中国石油化工股份有限公司
  • 中石化(北京)化工研究院有限公司

Dates

Publication Date
20260508
Application Date
20241105

Claims (14)

  1. 1. A shaped catalyst comprising a lanthanum containing material and cordierite, wherein the cordierite comprises Mg and Fe in a molar ratio of Mg to Fe of greater than 1.
  2. 2. The shaped catalyst according to claim 1, wherein the molar ratio of Mg to Fe in the cordierite is from 1:0.01 to 0.5, preferably from 1:0.01 to 0.25.
  3. 3. The shaped catalyst of claim 1, wherein the cordierite further comprises Al and Si in a molar ratio of Mg to elemental elements of Al, si, fe of 1:0.2-1:0.2-0.9:0.01-0.5.
  4. 4. Shaped catalyst according to claim 1, wherein the lanthanum containing material is present in an amount of 10-60 wt%, preferably 50-60 wt%, based on the total weight of the shaped catalyst; And/or the lanthanum-containing substance includes at least one of lanthanum oxide, lanthanum hydroxide, and lanthanum oxycarbonate.
  5. 5. A method of preparing a shaped catalyst comprising sequentially shaping, drying and firing a mixture of a lanthanum containing material, cordierite and an optional binder, wherein the cordierite comprises Mg and Fe in a molar ratio of Mg to Fe greater than 1.
  6. 6. The method of claim 5, wherein the molar ratio of Mg to Fe in the cordierite is from 1:0.01 to 0.5, preferably from 1:0.01 to 0.25.
  7. 7. The method of claim 5, wherein the composition of the cordierite further comprises Al and Si, wherein the molar ratio of Mg to elemental Mg, si, fe in the cordierite is from 1:0.2 to 0.9:0.01 to 0.5.
  8. 8. The process according to claim 5, wherein the lanthanum containing material is used in an amount such that the lanthanum containing material is present in an amount of 10-60 wt%, preferably 50-60 wt%, based on the total weight of the shaped catalyst; And/or the lanthanum-containing substance includes at least one of lanthanum oxide, lanthanum hydroxide, and lanthanum oxycarbonate.
  9. 9. The method of claim 5, wherein the binder comprises starch and/or an organic adhesive, preferably the starch is a soluble starch; and/or, the binder is used in an amount of 70-500g per 100g of lanthanum-containing substance; And/or water is also included in the mixture, the water being used in an amount of 100-400g per 100g of lanthanum containing material.
  10. 10. The method of claim 5, wherein the drying comprises a first drying and a second drying, the first drying conditions comprising a temperature of 15-40 ℃ for a time of 24-50 hours, and the second drying conditions comprising a temperature of 100-120 ℃ for a time of 10-20 hours; And/or the roasting condition comprises that the temperature is 450-650 ℃ and the time is 2-24h.
  11. 11. The method of claim 5, wherein the cordierite has an average particle diameter of 0.1-100 microns, preferably 0.1-50 microns; And/or the mixture is obtained by ball milling cordierite, adding lanthanum-containing substances for ball milling, and mixing with a binder and water.
  12. 12. A shaped catalyst prepared by the process of any one of claims 5-11.
  13. 13. Use of the shaped catalyst according to any one of claims 1-4 and 12 in a methane oxidative coupling reaction.
  14. 14. The process according to claim 13, wherein the conditions for the oxidative coupling of methane comprise a temperature of 500-850 ℃, a molar ratio of methane to oxygen of 2-10:1 and a reaction space velocity of 5000-200000ml/gh in terms of methane.

Description

Shaped catalyst, preparation method and application thereof Technical Field The invention relates to the technical field of catalysts, in particular to a formed catalyst and a preparation method and application thereof. Background Methane is the main component of natural gas, the direct oxidation conversion is a target of scientific research and competitive research of various enterprises, the direct oxidation conversion has good atomic economy and environment-friendly reaction process, the catalyst with high activity, high stability and high selectivity is a main hot spot of the prior research, the research of the catalyst is over forty years, a catalyst system suitable for different temperature ranges is developed, the catalyst system mainly adopts a micro-reverse filling catalyst in a laboratory, the catalyst forming is an industrial amplifying step, the catalyst performance is directly influenced by the formula and the forming mode of the catalyst, the catalyst is formed by adding a binder and a diluent in the method commonly adopted at present, and the formed catalyst can meet the filling requirement of an industrial device on the catalyst. Cordierite is a silicate mineral, the main chemical component of which is magnesium-aluminum cyclic silicate, the chemical formula of which is Mg 2Al4Si5O18, and the chemical component of which can contain Na, K, ca, fe, mn and other elements and H 2 O. The chemical composition and crystal habit of cordierite give it unique physical properties in that Mg and Fe can form complete, homomorphic substitution and the refractive index increases with increasing iron content. When the content of iron element is greater than that of magnesium element, the iron element is called iron cordierite, the chemical formula of the iron cordierite is (Mg, fe 2+)2Al3[AlSi5O18), and when the content of magnesium element is greater than that of iron element, the iron element is called cordierite. Disclosure of Invention The object of the present invention is to provide a shaped catalyst having a high mechanical strength, preferably capable of improving the conversion of methane and the selectivity of hydrocarbons of two or more carbons when used in the oxidative coupling reaction of methane. The inventor of the present invention found that when a molded catalyst is prepared from cordierite having a molar ratio of lanthanum-containing substance to Mg to Fe of greater than 1, the molded catalyst prepared not only has a high mechanical strength, but also can significantly improve the conversion of methane and the hydrocarbon selectivity of two or more carbons when the molded catalyst is used for oxidative coupling of methane. In order to achieve the above object, the first aspect of the present invention provides a shaped catalyst comprising a lanthanum containing substance and cordierite, wherein the cordierite has a composition comprising Mg and Fe and wherein the molar ratio of Mg to Fe in the cordierite is greater than 1. In a second aspect, the invention provides a method of preparing a shaped catalyst comprising sequentially shaping, drying and firing a mixture of a lanthanum containing material, cordierite and optionally a binder, wherein the cordierite comprises a composition comprising Mg and Fe and the molar ratio of Mg to Fe in the cordierite is greater than 1. The third aspect of the invention provides a shaped catalyst prepared by the method described above. In a fourth aspect, the present invention provides the use of a shaped catalyst as described above in the oxidative coupling of methane. Through the technical scheme, the method of the invention has the following beneficial effects: (1) The formed catalyst has higher mechanical strength and can meet the requirements of equipment on the catalyst in the industrial amplifying process. The shaped catalyst of the invention can improve the conversion of methane and the hydrocarbon selectivity of two or more carbon atoms when being used for oxidative coupling of methane. (2) Preferably, when the shaped catalyst of the present invention contains cordierite having a specific Mg to Fe molar ratio, the mechanical strength of the shaped catalyst, as well as the conversion of methane and the selectivity to hydrocarbons of two or more, can be further improved. (3) The invention prepares the molded catalyst by molding cordierite with lanthanum-containing substances and Mg and Fe with the mol ratio of more than 1, the method disclosed by the invention is simple to operate, is convenient for industrial application, and has higher industrial application value. 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 t