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CN-122006712-A - Preparation method and application of ethanol anaerobic dehydrogenation catalyst

CN122006712ACN 122006712 ACN122006712 ACN 122006712ACN-122006712-A

Abstract

The application discloses a preparation method and application of an ethanol anaerobic dehydrogenation catalyst, and belongs to the field of catalysts. The preparation method comprises the steps of S1 mixing copper salt and ammonia water to obtain a copper ammonia solution, S2 dropwise adding the copper ammonia solution into an alcohol solution of orthosilicate, aging, separating, washing, drying and roasting to obtain the ethanol anaerobic dehydrogenation catalyst. The preparation process does not need to add any auxiliary agent, has no limit to hydrolysis temperature, can finish preparation in normal temperature and below environment, and greatly improves the operation simplicity and the condition compatibility. The catalyst prepared by the method has excellent dispersibility of active components (copper species), high catalytic activity and strong sintering resistance, can fully exert active site efficacy in ethanol anaerobic dehydrogenation reaction, and has more outstanding catalytic activity and structural stability compared with the traditional catalyst, and obvious application potential.

Inventors

  • ZHANG YULING
  • PEI RENYAN
  • ZHANG ZIQIANG
  • ZHAO WEI
  • GAO WENWEN
  • DONG HUIFANG
  • TONG JUN
  • WANG HUI

Assignees

  • 延长中科（大连）能源科技股份有限公司

Dates

Publication Date
20260512
Application Date
20251208

Claims (10)

  1. 1. A method for preparing an ethanol anaerobic dehydrogenation catalyst, which is characterized by comprising the following steps: S1, mixing copper salt and ammonia water to obtain a copper ammonia solution; S2, dropwise adding the cuprammonium solution into an alcohol solution of the tetrasilicate, aging, separating, washing, drying and roasting to obtain the ethanol anaerobic dehydrogenation catalyst.
  2. 2. The preparation method of the composite material is characterized in that the mass ratio of the material dosage is SiO 2 ：Cu 2+ ：NH 3 to ROH=1, (0.03 to 0.2): (0.05 to 0.4): (5 to 15); wherein ROH represents an alcohol.
  3. 3. The method according to claim 1, wherein in step S1, the copper salt is at least one selected from the group consisting of copper nitrate, copper acetate, copper sulfate, and copper chloride; the mass concentration of the ammonia water is 20-30wt%.
  4. 4. The method according to claim 1, wherein in step S2, the orthosilicate is at least one selected from the group consisting of methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, and butyl orthosilicate; the alcohol is at least one selected from methanol, ethanol and propanol.
  5. 5. The method according to claim 1, wherein in step S2, the aging temperature is 10 to 80 ℃ and the aging time is 5 to 20 hours.
  6. 6. The method according to claim 1, wherein in step S2, the baking is performed in an air atmosphere at 300 to 600 ℃ for 2 to 12 hours.
  7. 7. The method for preparing the ethanol anaerobic dehydrogenation catalyst disclosed in any one of claims 1-6 is applied to preparing acetaldehyde through ethanol anaerobic dehydrogenation.
  8. 8. The use according to claim 7, characterized in that the reduction treatment is carried out before use, the reduction being carried out in a hydrogen-containing atmosphere at a reduction temperature of 200-400 ℃ for a time of 1-12 hours.
  9. 9. The use according to claim 7, wherein the hydrogen-containing atmosphere comprises hydrogen and an inert gas; The volume content of the hydrogen is 1-100%.
  10. 10. The use according to claim 7, wherein the ethanol feedstock is contacted with an ethanol anaerobic dehydrogenation catalyst to obtain acetaldehyde; The space velocity of the ethanol is 1-5 h -1 , and the reaction temperature is 100-400 ℃.

Description

Preparation method and application of ethanol anaerobic dehydrogenation catalyst Technical Field The application relates to a preparation method and application of an ethanol anaerobic dehydrogenation catalyst, and belongs to the field of catalysts. Background With the penetration of the sustainable development concept, the global demand for clean energy and green chemical production has grown dramatically. Ethanol is used as a renewable platform compound with wide sources, and the high-value utilization of the ethanol becomes the core direction in the fields of green chemical industry and energy transformation. Compared with the traditional fuel application, the ethanol is used for preparing high-added-value chemicals, materials and clean energy sources through the technologies of catalytic conversion, chemical synthesis and the like, and has higher economic value and environmental benefit. The oxygen-free dehydrogenation of ethanol to prepare acetaldehyde is one of key reactions for high-value utilization of ethanol. Acetaldehyde is an extremely important intermediate of organic chemical industry, has wide application in a plurality of industries such as pesticides, medicines, foods, spices and the like, and can be used for synthesizing various high-added-value products such as acetic acid, acetate, crotonaldehyde, pyridine compounds and the like. Meanwhile, the high-purity hydrogen which is a byproduct of the reaction is also an important component part in a future clean energy system, and can be used in a plurality of fields such as fuel cells, chemical synthesis and the like. In addition, the reaction of preparing acetaldehyde by ethanol anaerobic dehydrogenation can be realized in a fixed bed reactor, the equipment requirement is relatively simple, and the method provides convenience for industrial production. In the research of ethanol anaerobic dehydrogenation catalysts, although various types of catalysts have been developed, there are problems. Taking copper-based catalysts as an example, the copper-active components are susceptible to sintering deactivation by thermomigration and aggregation during the reaction, although they have higher initial activity and better selectivity. This is because copper atoms have high migration activity at high temperature, and nano copper particles which are originally highly dispersed on the surface of the carrier gradually fuse and grow up, and the catalytic activity is reduced. Moreover, some current catalyst preparation processes involve complex synthesis steps and expensive raw materials, increasing production costs and limiting large-scale industrial applications. Therefore, development of an ethanol anaerobic dehydrogenation catalyst having high activity, high stability, low cost, and being capable of adapting to a wide range of reaction conditions is urgent. Disclosure of Invention According to a first aspect of the present application, there is provided a method for preparing an ethanol anaerobic dehydrogenation catalyst. A method for preparing an ethanol anaerobic dehydrogenation catalyst, the method comprising: S1, mixing copper salt and ammonia water to obtain a copper ammonia solution; S2, dropwise adding the cuprammonium solution into an alcohol solution of the tetrasilicate, aging, separating, washing, drying and roasting to obtain the ethanol anaerobic dehydrogenation catalyst. Optionally, the mass ratio of the using amount of each material is (0.03-0.2): 0.05-0.4): 5-15) of SiO 2：Cu2+：NH3 and ROH=1; wherein ROH represents an alcohol. Optionally, in step S1, the copper salt is at least one selected from copper nitrate, copper acetate, copper sulfate and copper chloride; the mass concentration of the ammonia water is 20-30wt%. Optionally, in step S2, the orthosilicate is at least one selected from methyl orthosilicate, ethyl orthosilicate, propyl orthosilicate, and butyl orthosilicate; the alcohol is at least one selected from methanol, ethanol and propanol. Optionally, in step S2, the aging temperature is 10-80 ℃ and the aging time is 5-20 hours. Optionally, the aging temperature is any value or range of values between any two of 10 ℃, 20 ℃,30 ℃, 40 ℃, 50 ℃,60 ℃, 70 ℃, 80 ℃. Optionally, in step S2, the drying temperature is 90-150 ℃. Optionally, in step S2, the baking is performed in an air atmosphere, the baking temperature is 300-600 ℃, and the baking time is 2-12 hours. According to the preparation method, copper ions are used as precursors to form a stable ammonia complexing solution, the stable ammonia complexing solution is mixed with an orthosilicate alcohol solution under stirring, and the copper complex is uniformly dispersed and coated in a silicon-based carrier through slow hydrolysis of the stable ammonia complexing solution. The process has no auxiliary agent, is not limited by hydrolysis temperature (can be prepared at normal temperature or below), and is simple and convenient to operate. The obtained catalyst active component (copper