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CN-119076049-B - Ce/HZSM-5 catalyst and preparation method and application thereof

CN119076049BCN 119076049 BCN119076049 BCN 119076049BCN-119076049-B

Abstract

The invention provides a Ce/HZSM-5 catalyst, a preparation method and application thereof, wherein the mass fraction of Ce in the Ce/HZSM-5 catalyst is 1-2wt% based on the mass of the Ce/HZSM-5 catalyst. The mass fraction of Ce in the Ce/HZSM-5 catalyst provided by the invention is 1-2wt%, and the Ce loaded on the HZSM-5 can not only realize the adjustment of the acidity of the Ce/HZSM-5 catalyst, but also avoid the reduction of the pore volume and the pore diameter of the Ce/HZSM-5 catalyst caused by the accumulation of Ce in a zeolite channel of the HZSM-5, so that the Ce/HZSM-5 catalyst has higher activity and selectivity on hydrocarbon, thereby improving the conversion rate of oxygen-containing compounds in PET pyrolysis oil.

Inventors

  • WANG DONG
  • MIN RUI
  • WANG ZHI
  • QI TAO
  • XIAO WANHAI
  • LIN YONG
  • LI GUOBIAO

Assignees

  • 中国科学院赣江创新研究院
  • 中国科学院过程工程研究所

Dates

Publication Date
20260508
Application Date
20240830

Claims (17)

  1. 1. The application of the Ce/HZSM-5 catalyst is characterized in that the Ce/HZSM-5 catalyst is used for converting oxygen-containing compounds in PET pyrolysis oil of waste photovoltaic modules into gasoline-grade hydrocarbons; And taking the mass of the Ce/HZSM-5 catalyst as a percentage, wherein the mass fraction of Ce in the Ce/HZSM-5 catalyst is 1-2wt%.
  2. 2. Use of the Ce/HZSM-5 catalyst according to claim 1, characterized in that the preparation method of the Ce/HZSM-5 catalyst comprises: Mixing the Ce salt solution and HZSM-5, wherein the mixing comprises heating at constant temperature and simultaneously carrying out ultrasonic cavitation to obtain a mixed solution, and then carrying out heat treatment to obtain the Ce/HZSM-5 catalyst.
  3. 3. The use according to claim 2, wherein the mass ratio of Ce salt to HZSM-5 in the Ce salt solution is (0.024-0.048): 1.
  4. 4. The use according to claim 2, wherein the mass ratio of solvent to HZSM-5 in the Ce salt solution is (15-20): 1.
  5. 5. The use according to claim 2, wherein the ratio of silica to alumina in HZSM-5 is (20-30): 1.
  6. 6. The use according to claim 2, wherein the mixing time is 30-90 min.
  7. 7. The use according to claim 2, characterized in that the constant temperature heating is at a temperature of 60-100 ℃.
  8. 8. The use according to claim 2, wherein the mixing further comprises stirring in synchronization with constant temperature heating and ultrasonic cavitation.
  9. 9. The use according to claim 8, wherein the stirring speed is 300-900 rpm.
  10. 10. The use of claim 2, wherein the power of the ultrasonic cavitation is 300-600 w.
  11. 11. The use according to claim 2, further comprising drying between the mixing and the heat treatment.
  12. 12. The use according to claim 11, wherein the drying is at a temperature of 105-120 ℃ for a time of 10-14 hours.
  13. 13. The use according to claim 2, wherein the heat treatment comprises a sequential heating and incubation.
  14. 14. The use according to claim 13, wherein the rate of temperature increase is 1-10 ℃ per minute.
  15. 15. The use according to claim 13, wherein the temperature rise is at an end point temperature of 550-650 ℃.
  16. 16. The use according to claim 13, wherein the incubation time is 3-5 hours.
  17. 17. The use according to any one of claims 2 to 16, wherein the preparation method of the Ce/HZSM-5 catalyst comprises: (1) Mixing a Ce salt solution and HZSM-5, wherein the mixing comprises the steps of carrying out ultrasonic cavitation at the power of 300-600W while heating at the constant temperature of 60-100 ℃, and stirring at the rotating speed of 300-900 rpm, wherein the mixing time is 30-90 min, so as to obtain a mixed solution, the mass ratio of Ce salt in the Ce salt solution to HZSM-5 is (0.024-0.048): 1, the mass ratio of solvent to HZSM-5 is (15-20): 1, and the silicon-aluminum ratio in the HZSM-5 is (20-30): 1; (2) And (3) drying the mixed solution obtained in the step (1), heating to 550-650 ℃ at a rate of 1-10 ℃ per minute, and then preserving heat for 3-5 hours to obtain the Ce/HZSM-5 catalyst.

Description

Ce/HZSM-5 catalyst and preparation method and application thereof Technical Field The invention belongs to the technical field of catalysts, relates to a Ce/HZSM-5 catalyst, and particularly relates to a Ce/HZSM-5 catalyst, and a preparation method and application thereof. Background The photovoltaic modules are the most central components in the photovoltaic power station, and the service lives of the photovoltaic modules are generally 20-30 years. With the rapid development of the photovoltaic industry, the number of waste photovoltaic modules is continuously increased, and the scrapping amount of the global photovoltaic modules is estimated to reach 7800 ten thousand tons by 2050. The waste photovoltaic modules mainly comprise materials such as glass, EVA, battery pieces, TPT back plates and the like. PET (polyethylene terephthalate) is a polymer widely used in synthetic fibers and plastic materials, and accounts for about 80% of TPT back sheets, so that the amount of PET waste in waste photovoltaic modules is considerable, and if the waste is not effectively recycled and utilized, serious resource waste and environmental pollution can be caused. In order to effectively recycle and utilize PET waste, one possible method is to thermally crack it to obtain a pyrolysis oil containing components such as aromatic hydrocarbons, olefins, and oxygenates. However, pyrolysis oil contains a high proportion of oxygenates (alcohols, carboxylic acids, benzoic acids, terephthalic acid and derivatives thereof), which reduce the quality of pyrolysis oil and are unsuitable for direct use in engine combustion. Therefore, the fuel must be improved by the catalytic reforming process. Reforming processes include hydrogenation, deoxygenation, aromatization and cyclization of unsaturated functionalities, particularly cleavage of C-C, C-O and C-O bonds. HZSM-5 molecular sieve is a commonly used catalyst, and has the advantages of large specific surface area, unique pore structure, adjustable surface acidity, high selectivity, strong adsorption capacity and the like, and most of oxygen-containing compounds can move to active acid sites along pore channels of HZSM-5. HZSM-5 molecular sieve has simultaneouslyAcid centers and Lewis acid centers, in the catalytic processThe acid centers are more likely to participate in catalytic deoxygenation reactions. The presence of an acidic center in the catalyst allows for easier cleavage and separation of the C-C and C-O bonds in the reactants by dehydration, cleavage, aromatization, isomerization, oligomerization, decarboxylation, dealkylation, and the like. Hydrocarbons and coke are also produced with the aid of acidic centres on the catalyst. The acidity of the catalyst should therefore be tailored to produce the best hydrocarbon yields while reducing the polymerization of more hydrocarbons to coke material, avoiding the coverage of the active acid sites of the HZSM-5 structure after plugging the channels, resulting in reduced activity and selectivity of the hydrocarbons. However, the acidity of the HZSM-5 molecular sieve catalyst disclosed in the prior art is difficult to regulate and has low activity and selectivity on hydrocarbon. CN111085253A discloses a preparation method of an HZSM-5 catalyst simultaneously loaded with Mn and Ce, which comprises the following steps of dissolving Mn (NO 3)4 and Ce (NO 3)4) in deionized water, adding an HZSM-5 molecular sieve, soaking for 4-6 hours, drying for 25-27 hours in an oven at 75-85 ℃, roasting the obtained precursor in a muffle furnace at 485-495 ℃ for 7-8 hours, and cooling. CN101757943a discloses a catalyst for synthesizing methanol by hydrogenation of carbon dioxide and a preparation method thereof. The catalyst for synthesizing methanol Cu-Zn-Ce-Zr-HZSM-5 by hydrogenating carbon dioxide is prepared by using HZSM-5 molecular sieve as a carrier and cerium zirconium as an auxiliary agent and adopting a parallel-flow coprecipitation impregnation method, wherein the mol ratio of Cu to Zn is 2-4:1, the mol ratio of Ce to Zr is 1-3:1, the mass content of Cu to Zn is 30% -70%, and the mass content of HZSM-5 is 5% -50%. The patent has the advantages of simple catalyst preparation process, no pollution, low energy consumption and production cost in the preparation process, high catalyst strength and long service life, and can obviously increase the economical efficiency of CO 2 chemical utilization and achieve the purposes of saving energy, reducing emission and changing the harmful into valuable. The HZSM-5 molecular sieve catalyst disclosed at present has certain defects, and has the problems that the acidity is difficult to regulate and the activity and the selectivity to hydrocarbon are low, so that the conversion rate of oxygen-containing compounds in PET pyrolysis oil is low. Therefore, development and design of a novel Ce/HZSM-5 catalyst and a preparation method thereof are important. Disclosure of Invention Aiming at the defects existing in