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CN-121988369-A - Modified Y-type molecular sieve and preparation method and application thereof

CN121988369ACN 121988369 ACN121988369 ACN 121988369ACN-121988369-A

Abstract

The invention relates to the technical field of nano catalytic materials, and discloses a modified Y-type molecular sieve, a preparation method and application thereof, wherein the modified Y-type molecular sieve comprises a Y-type molecular sieve and ruthenium element loaded on the Y-type molecular sieve, the temperature of a main reduction peak in a reduction curve obtained by H 2 -TPR test of the modified Y-type molecular sieve is 150-200 ℃, after the modified Y-type molecular sieve is reduced for 1H under 500 ℃ in a hydrogen atmosphere, the average grain diameter of ruthenium metal particles on the modified Y-type molecular sieve is 1.5-3.5nm through TEM characterization. The modified Y-type molecular sieve has good ruthenium dispersibility, high catalytic activity and good activity stability.

Inventors

  • WANG YINGYING
  • GONG SHAOFENG
  • Nie Pinting
  • XIONG YI
  • SONG YANG
  • ZOU KANG

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
20260508
Application Date
20241031

Claims (11)

  1. 1. The modified Y-type molecular sieve is characterized by comprising a Y-type molecular sieve and ruthenium element loaded on the Y-type molecular sieve; the temperature of a main reduction peak in a reduction curve obtained by the modified Y-type molecular sieve through an H 2 -TPR test is 150-200 ℃; After reduction for 1h at 500 ℃ in hydrogen atmosphere, the average particle diameter of ruthenium metal particles on the modified Y-type molecular sieve is 1.5-3.5nm through TEM characterization.
  2. 2. The molecular sieve of claim 1, wherein the temperature of the main reduction peak in the reduction curve obtained by the modified Y-type molecular sieve subjected to the H 2 -TPR test is 170-190 ℃; Preferably, the ruthenium element is contained in an amount of 0.33 to 1.83 wt%, preferably 0.5 to 1.45 wt%, based on the total amount of the modified Y-type molecular sieve.
  3. 3. The molecular sieve according to claim 1 or 2, wherein after reduction at 500 ℃ for 1h under hydrogen atmosphere, the average particle size of the ruthenium metal particles on the modified Y-type molecular sieve is 1.5-2.5nm as characterized by TEM.
  4. 4. A molecular sieve according to any one of claims 1 to 3, wherein the modified Y-type molecular sieve has a specific surface area of 500 to 900m 2 /g, preferably 700 to 900m 2 /g; preferably, the micropore specific surface area of the modified Y-type molecular sieve is 400-850m 2 /g, preferably 650-850m 2 /g; preferably, the modified Y-type molecular sieve has a pore volume of 0.25 to 0.5cm 3 /g, preferably 0.3 to 0.45cm 3 /g.
  5. 5. The preparation method of the modified Y-type molecular sieve is characterized by comprising the following steps: and carrying out hydrothermal crystallization on the material to be subjected to hydrothermal crystallization, which contains the ruthenium complex and the Y-type molecular sieve synthetic glue solution, and then drying and roasting.
  6. 6. The method of claim 5, wherein the ruthenium complex is obtained by a complexation reaction of a ruthenium source and a ligand; preferably, the ligand in the ruthenium complex is selected from at least one of ammonia, ethylenediamine, ethylamine, propylamine and N- [3- (trimethoxysilyl) propyl ] ethylenediamine, preferably ammonia; preferably, the ruthenium source is added in an amount of Ru, the molar ratio of Ru to ligand in the ruthenium complex being from 1:2 to 15, preferably from 1:3 to 10.
  7. 7. The process according to claim 5 or 6, wherein the ruthenium complex and the Y-type molecular sieve are used in an amount such that the content of ruthenium element in the prepared modified Y-type molecular sieve is 0.33 to 1.83 wt%, preferably 0.5 to 1.45 wt%, based on the total amount of the modified Y-type molecular sieve.
  8. 8. The method of any of claims 5-7, wherein the Y-type molecular sieve synthetic gum solution comprises a silicon source, an aluminum source, an alkali source, and water; Preferably, in the material to be hydrothermally crystallized, the silicon source is calculated as SiO 2 , the aluminum source is calculated as Al 2 O 3 , the ruthenium complex is calculated as Ru, and the molar ratio of each component is as follows, siO 2 :Al 2 O 3 , ru, alkali source, H 2 O is 10 (0.5-2), 0.001-0.15, 4-12, 50-500, preferably 10 (0.7-1.5), 0.04-0.1, 7-10 and 100-300.
  9. 9. The process according to any one of claims 5 to 8, wherein the hydrothermal crystallization conditions comprise a crystallization temperature of 90 to 120 ℃, preferably 100 to 115 ℃, a crystallization time of 12 to 48 hours, preferably 20 to 36 hours; preferably, the drying conditions comprise a drying temperature of 100-140 ℃ and a drying time of 1-4h; Preferably, the calcination conditions include a calcination temperature of 300-600 ℃, preferably 400-550 ℃, and a calcination time of 3-8 hours, preferably 4-7 hours.
  10. 10. A modified Y-type molecular sieve prepared by the method of any one of claims 5-9.
  11. 11. Use of the modified Y-type molecular sieve of any one of claims 1-4 and 10 in the field of ammonia decomposition hydrogen production.

Description

Modified Y-type molecular sieve and preparation method and application thereof Technical Field The invention relates to the technical field of nano catalytic materials, in particular to a modified Y-type molecular sieve and a preparation method and application thereof. Background The hydrogen energy as the secondary energy plays an important role in the development of renewable energy and fossil energy, but the popularization and application of the hydrogen energy are limited by the factors of high hydrogen storage cost, low transportation efficiency and the like. Ammonia is used as a hydrogen storage carrier, so that the hydrogen storage density is high, the transportation technology is mature, the on-site supply of hydrogen production on the distributed site is convenient, and the trouble caused by hydrogen storage and transportation is avoided. The key to the promotion and application of the ammonia hydrogen loading technology is the development level of ammonia decomposition catalysts. The existing catalyst system still needs the temperature above 600 ℃ to realize the efficient decomposition of ammonia to prepare hydrogen. The high temperature condition greatly reduces the use energy efficiency of hydrogen energy. Therefore, the development of the high-efficiency catalyst for reducing the ammonia decomposition reaction temperature is beneficial to improving the hydrogen energy efficiency in the ammonia hydrogen loading process, and has a very key effect on the industrial application and popularization of the ammonia hydrogen loading. The Y molecular sieve is a typical porous material, is a widely applied catalyst carrier, and has excellent stability, rich pore channel structures and adjustable acidity and alkalinity. The traditional impregnation method is to load active metal on the prepared Y molecular sieve carrier, so that the active metal on the prepared catalyst is uneven in size and is mainly distributed on the outer surface of the molecular sieve particles. Under high temperature environment, active metal is easy to sinter, and the activity is gradually reduced. The catalyst for producing hydrogen by ammonia decomposition generally adopts a supported catalyst, takes active metals Ru, ni, co and Fe as active metals, and takes carbon nano tubes, mgO, ceO 2 and molecular sieves as carriers. Wherein Cha et al report a catalyst of Y molecular sieve supported Ru prepared by ion exchange method [ CATALYSIS B:environmental.2021;283:119627], hu et al report a Ni-based catalyst supported HZSM-5 [ APPLIED CATALYSIS A:general.2018;562:49-57 ]. Some progress has been made in these catalyst studies, but there is still room for further improvement. Therefore, a catalyst having high catalytic activity while having high stability is required. Disclosure of Invention The invention aims to solve the problems of easy sintering and poor activity of active metals in a Y-type molecular sieve supported active metal catalyst in the prior art, and provides a modified Y-type molecular sieve, a preparation method and application thereof. In order to achieve the above object, a first aspect of the present invention provides a modified Y-type molecular sieve, wherein the modified Y-type molecular sieve comprises a Y-type molecular sieve and ruthenium element supported on the Y-type molecular sieve; the temperature of a main reduction peak in a reduction curve obtained by the modified Y-type molecular sieve through an H 2 -TPR test is 150-200 ℃; After reduction for 1h at 500 ℃ in hydrogen atmosphere, the average particle diameter of ruthenium metal particles on the modified Y-type molecular sieve is 1.5-3.5nm through TEM characterization. Preferably, the temperature of the main reduction peak in the reduction curve obtained by the H 2 -TPR test of the modified Y-type molecular sieve is 170-190 ℃. Preferably, the ruthenium element is contained in an amount of 0.33 to 1.83 wt%, preferably 0.5 to 1.45 wt%, based on the total amount of the modified Y-type molecular sieve. The second aspect of the invention provides a preparation method of a modified Y-type molecular sieve, wherein the method comprises the steps of carrying out hydrothermal crystallization on a material to be subjected to hydrothermal crystallization, which contains ruthenium complex and Y-type molecular sieve synthetic glue solution, and then drying and roasting. The third aspect of the invention provides a modified Y-type molecular sieve prepared by the preparation method of the second aspect. The fourth aspect of the invention provides an application of the modified Y-type molecular sieve in the field of hydrogen production by ammonia decomposition. Through the technical scheme, the beneficial effects obtained are as follows: (1) The nano ruthenium metal particles in the modified Y-type molecular sieve provided by the invention have the advantages of high dispersity, high catalytic activity and good stability; (2) In the invention, preferably, the preparation me