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CN-121975546-A - Application of Cu-ZSM-22 catalyst in preparation of aviation kerosene component through hydrodeoxygenation coupling isomerization of methyl palmitate

CN121975546ACN 121975546 ACN121975546 ACN 121975546ACN-121975546-A

Abstract

The invention relates to the technical field of catalysis, and discloses an application of a Cu-ZSM-22 catalyst in preparing aviation kerosene components through hydrodeoxygenation coupling isomerization of methyl palmitate, which comprises the steps of 1) carrying out reduction treatment on the Cu-ZSM-22 catalyst, 2) filling the Cu-ZSM-22 catalyst into a reactor, mixing methyl palmitate with a solvent, introducing hydrogen for hydrodeoxygenation and hydroisomerization reaction to obtain products containing hexadecane and isomeric compounds, wherein the Cu-ZSM-22 catalyst takes a ZSM-22 molecular sieve as a carrier and copper species as an active component. The catalyst is used for preparing the aviation kerosene component by hydrodeoxygenation coupling isomerization of methyl palmitate, has the characteristics of low cost, high conversion rate of methyl palmitate, high selectivity to long-chain alkane, high isomerization ratio of products and the like, and can effectively improve the low-temperature fluidity of the aviation kerosene component.

Inventors

  • LIU LUJIE
  • WEI HAIYU
  • CHEN YONGXIANG
  • MA ZENGYI
  • YAN JIANHUA

Assignees

  • 浙江大学

Dates

Publication Date
20260505
Application Date
20260408

Claims (10)

  1. The application of the Cu-ZSM-22 catalyst in preparing aviation kerosene components by hydrodeoxygenation coupling isomerization of methyl palmitate is characterized by comprising the following steps: 1) Carrying out 200-380 ℃ reduction treatment on the Cu-ZSM-22 catalyst; 2) Filling the reduced Cu-ZSM-22 catalyst into a reactor, mixing methyl palmitate and a solvent, and introducing hydrogen to perform hydrodeoxygenation and hydroisomerization reaction to obtain a product containing hexadecane and an isomerism compound thereof, wherein the selectivity of the hexadecane is more than or equal to 50%, and the isomerism ratio of the hexadecane is more than or equal to 84%; The Cu-ZSM-22 catalyst takes a ZSM-22 molecular sieve with a silicon-aluminum molar ratio of 20-30:1 as a carrier and takes a copper species with an average particle size of 3-10nm as an active component, wherein the load of copper element in the Cu-ZSM-22 catalyst is 10-20wt%; The preparation method of the Cu-ZSM-22 catalyst comprises the steps of adding ammonia water into a copper acetate aqueous solution in batches according to the mass ratio of 2-4:1 of the ammonia water to the copper acetate, uniformly dispersing, adding a ZSM-22 molecular sieve, heating to evaporate ammonia, filtering, washing, drying and roasting at 300-500 ℃ to obtain the Cu-ZSM-22 catalyst.
  2. 2. The method according to claim 1, wherein in step 1), the reduction treatment is hydrogen-introduced reduction for 1-3 hours.
  3. 3. The method according to claim 1, wherein in step 2) the solvent is one or more of cyclohexane, dodecane, cyclopentane and 1, 4-dioxane.
  4. 4. The method according to claim 1 or 3, wherein in step 2) the methyl palmitate comprises 5 to 20% by weight of the sum of methyl palmitate and solvent.
  5. 5. The method according to claim 1 or 4, wherein in step 2), the reaction conditions are: Introducing 1-4MPa hydrogen into the reactor under normal pressure, and stirring at a speed of 300-800r/min; The reaction temperature is 150-300 ℃ and the reaction time is 1-3h.
  6. 6. The use according to claim 1, wherein the Cu-ZSM-22 catalyst has a loading of copper element of from 12 to 18wt%.
  7. 7. The use according to claim 1 or 6, wherein in the Cu-ZSM-22 catalyst the copper species comprises copper nanoparticles and/or copper oxide nanoparticles.
  8. 8. The method according to claim 1, wherein the step of adding ammonia in batches comprises adding ammonia in equal amounts in three batches during the preparation of the Cu-ZSM-22 catalyst.
  9. 9. The use according to claim 1 or 8, wherein the elevated temperature is 75-95 ℃ during the preparation of the Cu-ZSM-22 catalyst.
  10. 10. The use according to claim 1 or 8, wherein the calcination temperature is 300-450 ℃ during the preparation of the Cu-ZSM-22 catalyst.

Description

Application of Cu-ZSM-22 catalyst in preparation of aviation kerosene component through hydrodeoxygenation coupling isomerization of methyl palmitate Technical Field The invention relates to the technical field of catalysis, in particular to application of a Cu-ZSM-22 catalyst in preparing aviation kerosene components through hydrodeoxygenation coupling isomerization of methyl palmitate. Background Aviation kerosene is used as a core power source for aviation transportation, and currently mainly depends on a traditional petroleum-based preparation method, including a straight-run kerosene hydrofining method and a cracking process byproduct recovery method. The method comprises the steps of separating a kerosene fraction at 150-300 ℃ from crude oil distillation, removing impurities through hydrofining to meet aviation kerosene indexes, and recovering the kerosene fraction in catalytic cracking and hydrocracking byproducts, wherein the process is mature, the raw materials are highly dependent on petroleum, and the combustion of fossil fuels can release a large amount of atmospheric pollutants such as carbon monoxide, carbon dioxide, unburned hydrocarbon and the like, so that the air quality is deteriorated and other environmental problems are caused. Therefore, development of sustainable and low-emission clean aviation fuels (abbreviated as "aviation kerosene") has become a research hotspot and development direction in the energy field, mainly including sustainable aviation fuels (SAF or bio-jet fuels) and synthetic paraffin kerosene (bio-SPK), the production method of hydrogenated fatty acid esters (HEFA) in SAF is most mature, and carbon emission is obviously lower than other synthetic methods. Methyl Palmitate (MP) is used as a typical representative of biological grease derivatives, can be prepared on a large scale through transesterification of palm oil, abandoned animal and vegetable oil and the like, has the advantages of renewable raw materials, stable yield, controllable cost and the like, and is an ideal raw material for preparing aviation kerosene components in a biological grease hydro-conversion route. The core reaction of converting methyl palmitate into aviation kerosene component is Hydrodeoxygenation (HDO), and oxygen atoms in molecules are removed in the form of water, carbon dioxide and the like, so as to generate core effective components of biological aviation kerosene such as hexadecane, pentadecane and the like. However, HDO of methyl palmitate is limited by the cost and performance of the catalyst. In addition, the cracking of carbon-carbon bonds in the reaction process leads to low selectivity of long-chain alkane in the aviation kerosene component and insufficient isomerization capability of the catalyst, so that the aviation kerosene component faces key challenges such as lower thermal stability of fuel. Therefore, if a catalyst which has the advantages of controllable cost, high conversion rate of methyl palmitate, high selectivity to long-chain alkane (especially hexadecane), high isomerism ratio of products and high catalytic stability can be newly developed, the catalyst has important practical significance and industrial value for promoting the large-scale preparation of biological aviation kerosene and relieving energy and environmental pressure. Disclosure of Invention In order to overcome the defects in the prior art, the invention provides application of a Cu-ZSM-22 catalyst in preparing aviation kerosene components through hydrodeoxygenation coupling isomerization of methyl palmitate. The ZSM-22 molecular sieve loaded with copper species is used as a catalyst, and is used for preparing the aviation kerosene component by hydrodeoxygenation coupling isomerization of methyl palmitate, so that the aviation kerosene component has the characteristics of low cost (the catalyst does not contain noble metals), high conversion rate of methyl palmitate, high selectivity to long-chain alkane (hexadecane), high product isomerization ratio and the like, and the low-temperature fluidity of the aviation kerosene component can be effectively improved, thereby conforming to the use standard of aviation fuel. The specific technical scheme of the application comprises the application of the Cu-ZSM-22 catalyst in preparing aviation kerosene components through hydrodeoxygenation coupling isomerization of methyl palmitate, and the method comprises the following steps: 1) The Cu-ZSM-22 catalyst is subjected to a reduction treatment at 200-380 ℃, more preferably 250-350 ℃. 2) Filling the reduced Cu-ZSM-22 catalyst into a reactor, mixing methyl palmitate and a solvent, and introducing hydrogen to perform hydrodeoxygenation and hydroisomerization reaction to obtain a product containing hexadecane and its isomeric compounds (2-methylpentadecane, 2-ethyltetradecane, etc.), a small amount of palmitic acid and C 32 ester. Wherein, the selectivity of hexadecane is more than or equal to 50 percent, and th