Method for catalytically synthesizing dicyclopropane high-energy fuel by non-noble metal Cu
By using Cu/carbon nanotube unit point catalysts, the electron states of Cu atoms are regulated, and the problems of low selectivity of bicyclic products and high cost of precious metal catalysts in isoprene preparation are solved, and efficient and economical synthesis of bicyclic propane-based high-energy fuels are achieved.
Patent Information
- Application Number
- CN202411828635.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-12
- Publication Date
- 2025-03-21
AI Technical Summary
In the prior art, there are problems with low selectivity of bicyclic products for preparing high-energy fuels and high cost of precious metal catalysts.
Non-precious metal Cu catalyst is used, specifically a Cu/carbon nanotube unit point catalyst is used to regulate the electron state of Cu atoms by supporting the Cu compound on the carbon nanotube, thereby improving the reaction conversion rate and bicyclic product selectivity.
The reaction conversion rate and bicyclic product selectivity are significantly improved, the conversion rate can reach more than 50%, the selectivity can reach more than 30%, and it has the advantages of high atomic economy, mild reaction conditions, and recycling.
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Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of high-energy fuel synthesis, and in particular relates to a method for synthesizing a dicyclopropane-based high-energy fuel. Background Art
[0002] Aerospace development, power comes first! As the fundamental power source of aerospace engines, high-energy fuels directly determine the performance of aircraft, and the continuous development of my country's aerospace industry has put forward higher requirements for high-energy fuels. Among them, hydrocarbon high-energy fuels have the advantages of being non-toxic and green, but there is still a problem of insufficient energy density. The introduction of cyclopropane structure into hydrocarbon high-energy fuels can store torsional tension and angular tension energy in the molecular structure, making it have higher energy. On the other hand, compared with straight-chain hydrocarbon high-energy fuels, the molecular stacking of cyclopropane-based hydrocarbon high-energy fuels is more compact and has a higher density. The joint improvement of energy and density can greatly improve the volume calorific value of cyclopropane-based hydrocarbon high-energy fuels, and has better application prospects in the field of aerospace.
[0003] At present, the methods for synthesizing the corresponding bicyclopropane high-energy fuel using isoprene as raw material are very limited, and there are problems such as low selectivity and high cost of using precious metals. The document Bulletin of the Academy of Sciences of the USSR, 1989, 38, 1707-1714 reported that the noble metal complex Pd(acac)2 was used as a catalyst to catalyze the synthesis of the corresponding cyclopropane high-energy fuel from isoprene at -10°C in ether solvent. The experimental results showed that the yield of the monocyclic product was 63%, and the yield of the bicyclic product was only 5%; the document Doklady Akademiinayauk, 1961, 139 (6), 1379-1382 disclosed that the monocyclic product of isoprene was reacted with CH2I2 using a Zn-Cu couple as a catalyst, and the yield of the generated bicyclic product was only 18.1%. Summary of the invention
[0004] In view of the technical problems of low selectivity of bicyclic products in high-energy fuel prepared from isoprene and high cost of precious metal catalysts, the present invention proposes a method for synthesizing bicyclopropane-based high-energy fuel using non-precious metal Cu catalysis, which has the advantages of high conversion rate, high selectivity, high atom economy, mild reaction conditions, and recyclability.
[0005] In order to achieve the above object, the technical solution of the present invention is achieved as follows:
[0006] A method for synthesizing a dicyclopropane-based high-energy fuel using non-precious metal Cu as catalyst comprises the following steps: mixing a Cu / carbon nanotube single-site catalyst, isoprene, an organic solvent and an alkaline solution, adding a diazo precursor to react, obtaining a two-phase solution after the reaction, and extracting and separating to obtain a dicyclo product.
[0007] The preparation method of the Cu / carbon nanotube single-site catalyst is as follows: immersing carbon nanotubes in an acetone solution (1 g / L) containing a Cu compound to load the Cu compound on the carbon nanotubes, filtering and drying to obtain the Cu / carbon nanotube single-site catalyst.
[0008] The Cu compound is any one or more of copper diacetylacetonate, copper trifluoroacetate, copper acetate, copper chloride, copper nitrate, copper citrate, copper tetraphenylporphyrin, and copper phthalocyanine.
[0009] The carbon nanotubes are single-walled or multi-walled, with a tube diameter of 1-50 nm and a tubular microscopic morphology.
[0010] The mass fraction of Cu in the Cu / carbon nanotube single-site catalyst is 0.1-10%.
[0011] The diazo precursor is one or more of N-methyl-N-nitrosourea, N-methyl-N-nitroso-p-toluenesulfonamide or N-methyl-N-nitroso-N′-nitroguanidine.
[0012] The organic solvent is one or more of methanol, ethanol, ether, n-hexane, cyclohexane, dichloromethane, tetrachloroethane, dioxane, dimethyl sulfoxide or N,N-dimethylformamide.
[0013] The alkali solution is an aqueous solution of potassium hydroxide or sodium hydroxide with a concentration of 15wt%-60wt%.
[0014] The molar ratio of isoprene to the diazo precursor is 1:1-1:6, the amount of Cu substance in the Cu / carbon nanotube single-site catalyst is 0.05-2.00 mol% of isoprene, the amount of hydroxide substance in the alkali solution is 15 times that of isoprene, and the concentration of isoprene is 0.2-0.5 mol / L;
[0015] The reaction temperature is -20-60°C and the reaction time is 0.5-3h. After the reaction is completed, a dilute acid quencher can be used to quench the reaction and then separate.
[0016] Beneficial effects of the present invention: The present invention uses Cu / carbon nanotube single-site catalysts to significantly improve the reaction conversion rate and the selectivity of the bicyclic product, and the conversion rate can reach more than 50%, and the highest can reach more than 77%; the selectivity can reach more than 30%, and the highest can reach more than 45%. This is mainly attributed to the bending strain of the Cu compound caused by the carbon nanotubes, which regulates the electronic state of the Cu atoms, thereby improving the reaction conversion rate and the selectivity of the bicyclic product of isoprene. In addition, compared with the prior art, the present invention also has the advantages of high atomic economy, mild reaction conditions, and recyclability. The precise and efficient synthesis of cyclopropane-based high-energy fuels will help the rapid development of my country's aerospace industry. BRIEF DESCRIPTION OF THE DRAWINGS
[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.
[0018] Figure 1 is the reaction equation for the cyclopropanation of isoprene.
[0019] Figure 2 The catalytic performance of Cu / carbon nanotube single-site catalysts, Cu(acac)2, and Cu / graphene single-site catalysts are compared under the same reaction conditions.
[0020] Figure 3 Schematic diagram of the bending strain of Cu / carbon nanotube single-site catalyst. DETAILED DESCRIPTION
[0021] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.
[0022] The preparation method of the Cu / carbon nanotube single-site catalyst used in the following Examples 1-12 is as follows: 61.5 mg of copper diacetylacetonate (Cu(acac)2) is dispersed in 2 g of acetone, 1 g of single-walled carbon nanotubes (tube diameter is 1-2 nm) is added, and 1.5 wt% Cu / carbon nanotubes are obtained by filtering and drying.
[0023] The preparation method of the Cu / carbon nanotube single-site catalyst used in the following Example 13 is as follows: 3.1 mg of copper acetate is dispersed in 2 g of acetone, 1 g of single-walled carbon nanotubes (tube diameter is 1-2 nm) is added, and 0.1 wt% Cu / carbon nanotubes are obtained by filtering and drying.
[0024] The preparation method of the Cu / carbon nanotube single-site catalyst used in the following Example 14 is as follows: 1 g of copper tetraphenylporphyrin is dispersed in 2 g of acetone, 1 g of single-walled carbon nanotubes (tube diameter is 1-2 nm) is added, and 10 wt% Cu / carbon nanotubes are obtained by filtering and drying.
[0025] The preparation method of the Cu / graphene single-site catalyst used in the following Comparative Example 2 is as follows: 41 mg of copper diacetylacetonate (Cu(acac)2) is dispersed in 2 g of acetone, 1 g of graphene is added, and 1 wt% Cu / graphene is obtained by filtering and drying.
[0026] Example 1
[0027] A method for synthesizing dicyclopropane-based high-energy fuel catalyzed by non-precious metal Cu, the isoprene cyclopropanation reaction equation is as follows Figure 1 As shown, the process comprises the following steps: first, at room temperature, 18 mL of CH2Cl2 solvent is added to a flask, then 0.601 mL of isoprene, 203.4 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, 9.8 g of 50 wt% KOH solution are added, and then 2.47 g of N-methyl-N-nitrosourea is slowly added. After reacting at room temperature of 20°C for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction.
[0028] The two-phase solution was obtained by standing and layering, and then extracted and separated. Finally, the concentration of each component in the organic phase was determined by gas chromatography. The conversion rate was calculated to be 77.4% and the selectivity of the bicyclic product was 45.7%.
[0029] Example 2
[0030] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: at room temperature, firstly, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 50.8 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 2.47 g of N-methyl-N-nitrosourea. After reacting at room temperature of 20°C for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. After standing and layering, a two-phase solution is obtained, which is then separated by extraction.
[0031] Example 3
[0032] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: first, at room temperature, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 110.7 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 2.47 g of N-methyl-N-nitrosourea. After reacting at room temperature of 20° C. for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. Standing and layering to obtain a two-phase solution, which is then separated by extraction.
[0033] Example 4
[0034] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: first, at room temperature, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 152.2 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 2.47 g of N-methyl-N-nitrosourea. After reacting at room temperature of 20° C. for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. Standing and layering to obtain a two-phase solution, which is then separated by extraction.
[0035] Example 5
[0036] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: at room temperature, first, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 254.3 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 2.47 g of N-methyl-N-nitrosourea. After reacting at room temperature of 20° C. for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. Standing and layering to obtain a two-phase solution, which is then separated by extraction.
[0037] Example 6
[0038] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: at room temperature, firstly, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 203.4 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 2.47 g of N-methyl-N-nitrosourea. After reacting at room temperature of 0°C for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. After standing and layering, a two-phase solution is obtained, which is then separated by extraction.
[0039] Example 7
[0040] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: first, at room temperature, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 203.4 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 2.47 g of N-methyl-N-nitrosourea. After reacting at room temperature of 10°C for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. Standing and layering to obtain a two-phase solution, which is then separated by extraction.
[0041] Example 8
[0042] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: at room temperature, firstly, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 203.4 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 2.47 g of N-methyl-N-nitrosourea. After reacting at room temperature of 30°C for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. After standing and layering, a two-phase solution is obtained, which is then separated by extraction.
[0043] Example 9
[0044] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: at room temperature, first, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 203.4 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 1.24 g of N-methyl-N-nitrosourea. After reacting at room temperature of 20°C for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. Standing and layering to obtain a two-phase solution, which is then separated by extraction.
[0045] Example 10
[0046] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: first, at room temperature, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 203.4 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 1.85 g of N-methyl-N-nitrosourea. After reacting at room temperature of 20° C. for 2 h, 24 mL of dilute hydrochloric acid is added to quench the reaction. Standing and layering to obtain a two-phase solution, which is then separated by extraction.
[0047] Embodiment 11
[0048] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: at room temperature, firstly, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 203.4 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 3.09 g of N-methyl-N-nitrosourea. After reacting at room temperature of 20° C. for 2 h, 24 mL of dilute hydrochloric acid is added to quench the reaction. After standing and layering, a two-phase solution is obtained, which is then separated by extraction.
[0049] Example 12
[0050] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: first, at room temperature, adding 18 mL of CH2Cl2 solvent into a flask, then adding 0.601 mL of isoprene, 203.4 mg of 1.5 wt% Cu / carbon nanotube single-site catalyst, and 9.8 g of 50 wt% KOH solution, and then slowly adding 3.7 g of N-methyl-N-nitrosourea. After reacting at room temperature of 20°C for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. Standing and layering to obtain a two-phase solution, which is then separated by extraction.
[0051] The conversion rate and selectivity of the bicyclic product of Example 2-12 are shown in Table 1.
[0052] Table 1 Examples 2-10
[0053]
[0054]
[0055] Comparative Example 1
[0056] In order to compare the catalytic effect of Cu / carbon nanotube single-site catalysts, a comparative experiment of homogeneous catalyst Cu(acac)2 was carried out.
[0057] At room temperature, 18 mL of CH2Cl2 solvent was first added to the flask, followed by 0.601 mL of isoprene, 12.9 mg of Cu(acac)2 (maintaining the same molar number of Cu as in Example 1), 9.8 g of 50 wt% KOH solution, and then 2.47 g of N-methyl-N-nitrosourea was slowly added. After reacting for 2 h, 24 mL of dilute hydrochloric acid was added to quench the reaction.
[0058] The two-phase solution was obtained by standing and layering, and then extracted and separated. Finally, the concentration of each component in the organic phase was determined by gas chromatography. The conversion rate was calculated to be 27.4%, the selectivity of the monocyclic product was 89.9%, and no bicyclic product was generated.
[0059] Comparative Example 2
[0060] In order to compare the catalytic effect of Cu / carbon nanotube single-site catalyst, a comparative experiment was conducted under Cu / graphene single-site catalyst (without bending strain, its preparation method is the same as Cu / carbon nanotube single-site catalyst, only the carbon nanotube is replaced by graphene).
[0061] At room temperature, 18 mL of CH2Cl2 solvent was first added to the flask, followed by 0.601 mL of isoprene, 305.0 mg of 1 wt% Cu / graphene single-site catalyst, 9.8 g of 50 wt% KOH solution, and then 2.47 g of N-methyl-N-nitrosourea was slowly added. After reacting for 2 h, 24 mL of dilute hydrochloric acid was added to quench the reaction.
[0062] The two-phase solution was obtained by standing and layering, and then extracted and separated. Finally, the concentration of each component in the organic phase was determined by gas chromatography. The conversion rate was calculated to be 33.7%, the selectivity of the monocyclic product was 34.9%, and the selectivity of the bicyclic product was 12.8%.
[0063] The catalytic performance of Example 1 and the comparative example is shown in the attached Figure 2 As shown in the figure, under Cu(acac)2 conditions, the conversion rate of isoprene was 27.4%, and no bicyclic product was generated; under Cu / graphene catalyst, the conversion rate increased to 77.4%, and the selectivity of bicyclic product was 5.6%; while under Cu / carbon nanotube catalyst, the conversion rate was 33.7%, and the selectivity of bicyclic product was further increased to 45.7%, indicating that the bending strain in Cu / carbon nanotube catalyst can significantly regulate the electronic state of Cu, thereby improving the selectivity of bicyclic product.
[0064] According to the density functional theory (DFT), the molecular structure of Cu / CNTs was optimized under PBE0 / 6-31G (d, p) using Gaussian16 software (see attached Figure 3 Cu(acac)2 is a planar molecule with a dihedral angle of 180° between O-Cu-O on both sides. Figure 3 It shows that after the interaction between Cu(acac)2 and carbon nanotubes, the O-Cu-O dihedral angles on both sides of Cu(acac)2 are bent and deformed, decreasing from 180° to 158°. This indicates that there is a significant bending strain effect between Cu(acac)2 and carbon nanotubes, which can cause changes in the coordination environment and electronic state of Cu atoms, thereby improving the selectivity of isoprene bicyclic products.
[0065] Example 13
[0066] A method for synthesizing a dicyclopropane high-energy fuel using a non-precious metal Cu catalyst comprises the following steps: first, at room temperature, adding 12 mL of N,N-dimethylformamide solvent into a flask, then adding 0.601 mL of isoprene, 48 mg of 0.1 wt% Cu / carbon nanotube single-site catalyst, and 10.8 g of 60 wt% KOH solution, and then slowly adding 3.53 g of N-methyl-N-nitroso-N′-nitroguanidine. After reacting at room temperature of 20° C. for 2 h, 24 mL of dilute hydrochloric acid is added to quench the reaction. After standing and layering, a two-phase solution is obtained, which is then separated by extraction.
[0067] Embodiment 14
[0068] A method for synthesizing a dicyclopropane high-energy fuel using non-precious metal Cu as catalyst comprises the following steps: first, at room temperature, 30 mL of ethanol solvent is added to a flask, then 0.601 mL of isoprene, 19 mg of 10 wt% Cu / carbon nanotube single-site catalyst, 7.8 g of 15 wt% NaOH solution are added, and then 4.07 g of N-methyl-N-nitroso-p-toluenesulfonamide is slowly added. After reacting at room temperature of 20° C. for 2 hours, 24 mL of dilute hydrochloric acid is added to quench the reaction. After standing and layering, a two-phase solution is obtained, which is then separated by extraction.
[0069] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.
Claims
1. A method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst, characterized in that: The method comprises the following steps: mixing Cu / carbon nanotube single-site catalyst, isoprene, organic solvent and alkali solution, adding diazo precursor to react, obtaining a two-phase solution after the reaction, and extracting and separating to obtain a bicyclic product.
2. The method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst according to claim 1, characterized in that: The preparation method of the Cu / carbon nanotube single-site catalyst is as follows: immersing carbon nanotubes in a solution containing a Cu compound, so that the Cu compound is loaded on the carbon nanotubes, and filtering and drying to obtain the Cu / carbon nanotube single-site catalyst.
3. The method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst according to claim 2, characterized in that: The Cu compound is any one or more of copper diacetylacetonate, copper trifluoroacetate, copper acetate, copper chloride, copper nitrate, copper citrate, copper tetraphenylporphyrin, and copper phthalocyanine.
4. The method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst according to claim 3, characterized in that: The carbon nanotubes are single-walled or multi-walled, with a tube diameter of 1-50 nm and a tubular microscopic morphology.
5. The method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst according to claim 4, characterized in that: The mass fraction of Cu in the Cu / carbon nanotube single-site catalyst is 0.1-10%.
6. The method for synthesizing dicyclopropane-based high-energy fuel catalyzed by non-precious metal Cu according to any of claims 1 to 5, characterized in that: The diazo precursor is one or more of N-methyl-N-nitrosourea, N-methyl-N-nitroso-p-toluenesulfonamide or N-methyl-N-nitroso-N′-nitroguanidine.
7. The method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst according to claim 6, characterized in that: The organic solvent is one or more of methanol, ethanol, ether, n-hexane, cyclohexane, dichloromethane, tetrachloroethane, dioxane, dimethyl sulfoxide or N,N-dimethylformamide.
8. The method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst according to claim 7, characterized in that: The alkali solution is an aqueous solution of potassium hydroxide or sodium hydroxide with a concentration of 15wt%-60wt%.
9. The method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst according to claim 8, characterized in that: The molar ratio of isoprene to the diazo precursor is 1:1-1:6, the amount of Cu substance in the Cu / carbon nanotube single-site catalyst is 0.05-2.00 mol% of isoprene, the amount of hydroxyl substance in the alkali solution is 5-20 times of isoprene, and the concentration of isoprene in the organic solvent is 0.2-0.5 mol / L.
10. The method for synthesizing dicyclopropane-based high-energy fuel using non-precious metal Cu catalyst according to claim 9, characterized in that: The reaction temperature is -20-60°C and the reaction time is 0.5-3h.