A method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds
By using the metal carbon-nitrogen catalyst generated by the zeolite imidazole ester framework structure material, the problem of poor stability of non-precious metal catalysts in the reduction amination of aldehyde ketone compounds is solved, and efficient aldehyde ketone compounds is achieved, reducing costs and Improved product yield.
Patent Information
- Application Number
- CN202310279126.6
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- Filing Date
- 2023-03-21
- Publication Date
- 2024-12-20
- Estimated Expiration
- 2043-03-21
AI Technical Summary
In the prior art, when reducing amination of aldehyde ketone compounds is used using non-precious metals such as Cu, Co, and Ni as catalysts, it is easy to form complex ammonia ions with ammonia and become inactive, resulting in poor catalyst stability and high cost.
The zeolite imidazole ester skeleton structure material (ZIF) is used as the precursor for carbonization to form a metal carbon-nitrogen compound catalyst, and the reduction amination reaction of aldehyde ketone compounds is carried out in combination with an autoclave and ammonia methanol solution. The hydrogen and inert gas environment are used to improve the catalyst stability and activity.
It improves the stability and activity of non-precious metal catalysts, reduces the cost of reducing amination catalysts, provides a new effective path for reducing amination of biomass-based aldehyde ketone compounds, and improves product yield and catalyst service life.
Smart Images
Figure BDA0004137560130000021
Abstract
Description
Technical Field
[0001] The invention relates to the fields of chemistry and chemical engineering and catalytic science, and in particular to a method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds. Background Art
[0002] Amines are an important class of compounds found in natural products and medicines, and are used in the fields of chemical industry, agriculture, and medicine. Specifically, amines are used in pesticides, medicines, dyes, surfactants, detergents, curing agents, etc. Among them, primary amines are regarded as the most important and widely used organic amines due to their wide range of derivatization. In addition, some pharmaceutical intermediates and biomacromolecules also contain a large number of amine compounds. According to incomplete statistics, more than 80% of commonly used medicines contain amino groups. At present, the raw materials of amine compounds mostly come from petrochemicals. The preparation of organic amines by reductive amination of biomass aldehyde and ketone derivatives can effectively alleviate the shortage of fossil energy and help achieve the dual carbon goals.
[0003] In the process of reductive amination of aldehydes and ketones, noble metals such as Ru are usually used as catalysts. Such catalysts are insoluble in ammonia and have stable performance, but noble metals are expensive. Therefore, the use of non-noble metals such as Cu, Co, and Ni as catalysts for reductive amination has been the focus of attention in recent years. However, due to the presence of ammonia, Cu, Co, and Ni are easily lost by forming complex ammonium ions with it, thereby causing the catalyst to be deactivated. Summary of the invention
[0004] The purpose of the present invention is to solve the above problems in the prior art and to provide a method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds.
[0005] In order to achieve the above object, the present invention adopts the following technical scheme:
[0006] A method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds comprises the following steps:
[0007] 1) synthesizing a zeolite imidazolate framework material precursor with a metal salt and an organic ligand under hydrothermal or reflux conditions, and after centrifugal filtration, performing a high-temperature carbonization treatment under an inert atmosphere, and the obtained solid powder is used for subsequent reactions;
[0008] 2) Weigh the solid powder and aldehyde-ketone compound obtained in step 1) into a high-pressure reactor, add a certain concentration of ammonia methanol solution as a solvent into the high-pressure reactor, seal the high-pressure reactor, repeatedly remove the air in the reactor with inert gas and check for leaks, fill the reactor with a certain pressure of hydrogen while ensuring that the reactor is completely sealed, and then place it at a set temperature and heat it for a period of time. The obtained product is filtered using an organic membrane and then subjected to gas phase quantitative analysis.
[0009] The metal salt is composed of non-precious metals such as Cu, Co, Ni, etc. and nitrate, acetate, sulfate, carbonate, etc.
[0010] The organic ligand is one or more of benzimidazole, 1,10-phenanthroline, triazole, bipyridine and p-phenylenediamine.
[0011] The aldehyde and ketone compound is furfural or 5-hydroxymethylfurfural.
[0012] The molar concentration of ammonia in the ammonia methanol solution is 0.5 to 7 mol / L.
[0013] In step 2), the hydrogen pressure is 0.5-5 MPa.
[0014] In step 2), the heating reaction temperature is 100-200°C.
[0015] In step 2), the heating reaction time is 0.5 to 4 hours.
[0016] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:
[0017] The present invention adopts a zeolite imidazolate framework structure material (ZIF) material which not only has high porosity and organic function, but also combines the high stability of inorganic zeolite, and has higher activity and stability in the catalytic and separation processes. The metal and nitrogen atoms in the metal carbon nitrogen compound obtained by carbonization with the ZIF material as a precursor have weak interactions, the metal atoms are relatively stable, and the metal content is high, which can improve the stability of non-precious metal catalysts in amination reactions, and reduce the price of reductive amination catalysts, and can provide a new path for the reductive amination of biomass-based aldehyde and ketone compounds. DETAILED DESCRIPTION
[0018] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention clearer and more understandable, the present invention is further described in detail below in conjunction with embodiments.
[0019] The possible reaction pathways for the reductive amination of furfural in this example are as follows:
[0020]
[0021] Example 1
[0022] (1) Cobalt nitrate and benzimidazole were added to DMF solvent, stirred evenly and sealed in a hydrothermal kettle. After hydrothermal treatment at 130°C for 48 hours, the obtained solid was washed and dried and placed in a tube furnace. Nitrogen was introduced for purging and the temperature was raised to 700°C. After carbonization for 4 hours, the obtained solid powder was recorded as CoNC-1.
[0023] (2) Weigh 20 mg of the above-mentioned CoNC-1 catalyst, 0.5 mmol of furfural and 5 ml of 7 mol / L ammonia methanol solution in a high-pressure reactor, seal the reactor, replace the gas in the reactor with nitrogen three times, then fill it with 3 MPa H2, place the reactor in an oil bath with stirring and preheated to 100°C, react for 3 hours and cool it in cold water, and filter the obtained liquid through an organic membrane for gas phase analysis. The results show that furfural is completely converted, and the yield of the reductive amination product furfurylamine is 86%.
[0024] Example 2
[0025] Weigh 20 mg of the CoNC-1 catalyst in Example 1, 0.5 mmol of furfural, 0.5 ml of 7 mol / L ammonia methanol solution and 4.5 ml of methanol solution in a high-pressure reactor, seal the reactor, replace the gas in the reactor with nitrogen three times, then fill it with 3 MPa H2, place the reactor in an oil bath with stirring and preheated to 100°C, react for 3 hours and cool it in cold water, and filter the obtained liquid through an organic membrane for gas phase analysis. The results show that furfural is completely converted, and the yield of the reductive amination product furfurylamine is 85%.
[0026] Example 3
[0027] Weigh 20 mg of the CoNC-1 catalyst in Example 1, 0.5 mmol of furfural and 5 ml of 7 mol / L ammonia methanol solution in a high-pressure reactor, seal the reactor, replace the gas in the reactor with nitrogen three times, then fill it with 3 MPa H2, place the reactor in an oil bath with stirring and preheated to 180°C, react for 3 hours, cool in cold water, and filter the resulting liquid through an organic membrane for gas phase analysis. The results show that furfural is completely converted, and the yield of the reductive amination product furfurylamine is 70%.
[0028] Example 4
[0029] Weigh 20 mg of the CoNC-1 catalyst in Example 1, weigh 63 mg (0.5 mmol) of 5-hydroxymethylfurfural and 5 ml of 7 mol / L ammonia methanol solution in a high-pressure reactor, seal the reactor, replace the gas in the reactor with nitrogen three times, then fill it with 3 MPa H2, place the reactor in an oil bath with stirring and preheated to 200°C, react for 4 hours and cool it in cold water, and filter the resulting liquid through an organic membrane for gas phase analysis. The results show that 5-hydroxymethylfurfural is completely converted, the yield of the reductive amination product furan dimethylamine is 1%, and the yield of 5-hydroxymethylfurfurylamine is 42%.
[0030] Example 5
[0031] (1) Cobalt nitrate and phenanthroline were added to an ethanol solvent, stirred and refluxed in a water bath at 60°C for 36 hours, and the obtained solid was filtered, washed, dried, and placed in a tube furnace. Nitrogen was introduced for purging, and the temperature was raised to 600°C. After carbonization for 4 hours, the obtained solid powder was recorded as CoNC-2.
[0032] (2) Weigh 20 mg of the above-mentioned CoNC-2 catalyst, 0.5 mmol of furfural and 5 ml of 7 mol / L ammonia methanol solution in a high-pressure reactor, seal the reactor, replace the gas in the reactor with nitrogen three times, then fill it with 3 MPa H2, place the reactor in an oil bath with stirring and preheated to 100°C, react for 3 hours, cool it in cold water, and filter the obtained liquid through an organic membrane for gas phase analysis. The results show that furfural is completely converted, and the yield of the reductive amination product furfurylamine is 80%.
[0033] Comparative Example 1
[0034] 0.5mmol of furfural and 5ml of 7mol / L ammonia methanol solution were measured and placed in a high-pressure reactor. The reactor was sealed and the gas in the reactor was replaced with nitrogen three times. Then 3MPa H2 was filled in. The reactor was placed in an oil bath with stirring and preheated to 100°C. After reacting for 3h, it was cooled in cold water. The obtained liquid was filtered through an organic membrane and then subjected to gas phase analysis. The results showed that furfural was completely converted, there was almost no furfurylamine product, and the solution was dark brown, suspected to be a furfural polymerization product.
[0035] Comparative Example 2
[0036] (1) adding cobalt nitrate and benzimidazole to DMF solvent, stirring evenly and sealing in a hydrothermal kettle, hydrothermaling at 130° C. for 48 hours, and then washing and drying the obtained solid;
[0037] (2) Weigh 20 mg of the above-mentioned dried solid catalyst, 0.5 mmol of furfural and 5 ml of 7 mol / L ammonia methanol solution in a high-pressure reactor, seal the reactor, replace the gas in the reactor with nitrogen three times, then fill it with 3 MPa H2, place the reactor in an oil bath with stirring and preheated to 100°C, react for 3 hours, cool it in cold water, and filter the obtained liquid through an organic membrane for gas phase analysis. The results show that furfural is completely converted and the yield of the reductive amination product furfurylamine is 29%.
[0038] Traditional supported Co catalysts are easily complexed with ammonia and lost. The Co in the CoNC formed by the present invention has a weak interaction with N and is not easily complexed with ammonia. Therefore, it has better stability and excellent performance for furfural reductive amination.
[0039] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical solutions and inventive concepts of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.
Claims
1. A method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds, characterized in that: The following steps are involved: 1) synthesizing a zeolite imidazolate framework material precursor with a metal salt and an organic ligand under hydrothermal or reflux conditions, and after centrifugal filtration, performing a high-temperature carbonization treatment under an inert atmosphere, and the obtained solid powder is used for subsequent reactions; 2) Weigh the solid powder obtained in step 1) and the aldehyde and ketone compound into a high-pressure reactor, add a certain concentration of ammonia methanol solution as a solvent into the high-pressure reactor, seal the high-pressure reactor, fill it with hydrogen at a certain pressure, and heat it for reaction.
2. The method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds according to claim 1, characterized in that: The metal salts include metal salts of Cu, Co and Ni.
3. The method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds according to claim 1, characterized in that: The organic ligand is one or more of benzimidazole, 1,10-phenanthroline, triazole, bipyridine and p-phenylenediamine.
4. The method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds according to claim 1, characterized in that: The aldehyde and ketone compound is furfural or 5-hydroxymethylfurfural.
5. The method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds according to claim 1, characterized in that: The molar concentration of ammonia in the ammonia methanol solution is 0.5 to 7 mol / L.
6. The method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds according to claim 1, characterized in that: In step 2), the hydrogen pressure is 0.5-5 MPa.
7. The method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds according to claim 1, characterized in that: In step 2), the heating reaction temperature is 100-200°C.
8. The method for preparing organic amines by reductive amination of biomass-based aldehyde and ketone compounds as claimed in claim 1, characterized in that: In step 2), the heating reaction time is 0.5 to 4 hours.