Hydrocyanation reaction method

Abstract

The invention provides a hydrocyanation reaction method, the hydrocyanation reaction method is carried out in a reaction system containing aromatic amine under the action of a nickel-monodentate phosphite ligand catalyst, the structure of the aromatic amine is # imgabs0 #, and X1-X3 groups and Y1-Y3 groups respectively comprise any one of hydrogen, alkyl, alkoxy, alkylamino, hydroxyl and amino. The nickel-monodentate phosphite ligand catalyst and the aromatic amine with a specific structure are used in the hydrocyanation reaction method, so that the time of the hydrocyanation reaction method can be catalytically shortened, accumulation of ligand hydrolysate can be remarkably reduced or eliminated, and the loss of the catalyst in the reaction is reduced. The hydrocyanation reaction method disclosed by the invention is high in reaction efficiency, stable in catalyst performance, high in raw material conversion rate and product selectivity, and can be used for a preparation process for preparing adiponitrile by a direct hydrocyanation method of large-mass butadiene.

Description

Technical Field

[0001] The invention relates to the technical field of chemical synthesis, and in particular to a hydrocyanation reaction method. Background Art

[0002] Adiponitrile (ADN) is an important raw material intermediate for the production of nylon 66 and an important link in the nylon and specialty polyurethane industry chain. Among the various methods for producing adiponitrile, the direct hydrocyanation of butadiene is the mainstream process and has the highest global production capacity.

[0003] The process route for preparing adiponitrile by direct hydrocyanation of butadiene is as follows:

[0004]

[0005] The specific reaction steps include: one-step hydrocyanation, in which butadiene is reacted with hydrocyanic acid (HCN) under the action of a nickel catalyst to generate 2-methyl-3-butenenitrile (2M3BN) and 3-pentenenitrile (3PN); 2M3BN isomerization, in which 2M3BN is isomerized to 3PN under the action of a nickel catalyst; and two-step hydrocyanation, in which 3PN is isomerized to 4-pentenenitrile (4PN), which is then reacted with HCN to generate ADN and a by-product 2-methylglutaronitrile (MGN). This step of the reaction requires a nickel catalyst and a Lewis acid additive, has high requirements for catalyst activity, and is a key step in the entire reaction.

[0006] The direct hydrocyanation of butadiene involves a two-step hydrocyanation process. Taking the one-step hydrocyanation reaction as an example, the specific hydrocyanation reaction process is as follows:

[0007]

[0008] Among them, the zero-valent nickel-phosphorus catalyst [NiL4] (L is a ligand) removes a ligand molecule to form [NiL3], which then combines with HCN to form [HNiL3CN]; it continues to lose a ligand molecule to form [HNiL2CN], and then combines with butadiene to form an intermediate [C4H6-HNiL2CN]. This intermediate can react along two paths to generate two different substances, 3PN and 2M3BN, and regenerate [NiL3] to continue to participate in the catalytic cycle reaction.

[0009] However, in actual production, the hydrocyanation reaction faces many difficulties: First, the presence of water in the reaction system may cause the phosphite ligand of the nickel catalyst to hydrolyze, produce acidic hydrolysis products, further accelerate the ligand hydrolysis, and gradually cause the nickel-monodentate phosphite ligand catalyst to deactivate; second, when the HCN concentration in the reaction system is high, it will attack the active nickel ([NiL3] and [NiL2], etc.) of the hydrocyanation reaction to form nickel cyanide (Ni(CN)2) precipitates, causing catalyst deactivation; third, the hydrocyanation reaction (especially the two-step hydrocyanation reaction) has a slow rate and a long residence time, resulting in a high amount of catalyst deactivation. Therefore, developing a hydrocyanation reaction process with high reaction efficiency, high stability, and effective avoidance of catalyst deactivation is a technical problem that needs to be solved urgently. Summary of the invention

[0010] In view of the deficiencies in the prior art, the present invention discloses a hydrocyanation reaction method, which can not only shorten the reaction time, but also significantly reduce or eliminate the accumulation of ligand hydrolysis products, reduce the amount of nickel cyanide precipitation, and stabilize the catalyst.

[0011] In order to achieve the above technical objectives, on the one hand, the present invention provides a hydrocyanation reaction method, which is carried out in a reaction system containing aromatic amines under the action of a nickel-monodentate phosphite ligand catalyst, wherein the structure of the aromatic amine is:

[0012]

[0013] Among them, X 1 -X 3 Group and Y 1 -Y 3 The groups include any one of hydrogen, alkyl, alkoxy, alkylamino, hydroxyl, and amino.

[0014] As mentioned above, during the hydrocyanation reaction method, the active nickel intermediates (such as [NiL3] and [NiL2], etc.) are in a naked state due to the partial loss of ligands, and are easily attacked by polar molecules such as hydrocyanic acid and water to generate nickel cyanide and hydrolysis products, resulting in catalyst loss. In the above technical scheme, the aromatic amines with a specific structure are a class of compounds that have a strong complexing effect with nickel, which can coordinate with the active nickel intermediates in a timely manner during the hydrogenation reaction, thereby protecting the active nickel intermediates and reducing catalyst loss; at the same time, the aromatic amine compounds can form a hydrophobic environment around the active nickel intermediates, further reducing the possibility of catalyst hydrolysis and inhibiting the generation of hydrolysis products; and the improvement of the stability of the active nickel intermediates also effectively improves the overall hydrogenation reaction rate.

[0015] The effects of a hydrocyanation reaction method comprising a nickel-monodentate phosphite ligand catalyst and an aromatic amine are shown in the examples of the present invention.

[0016] In a further example of the present invention, 1 -X 3 Group and Y 1 -Y 3 The structure of the group is optimized. Optionally, the structural formula of the alkyl group is -R, and the structural formula of the alkoxy group is The structural formula of the alkylamino group is Wherein, the R group includes any one of methyl, ethyl, isopropyl and tert-butyl.

[0017] In some optional examples of the present invention, the aromatic amine can be selected from any one of Table 1.

[0018] Table 1

[0019] Serial number <![CDATA[X 1 ]]> <![CDATA[X 2 ]]> <![CDATA[X 3 ]]> <![CDATA[Y 1 ]]> <![CDATA[Y 2 ]]> <![CDATA[Y 3 ]]> Aromatic amine A1 hydrogen Methoxy hydrogen hydrogen Methoxy hydrogen Aromatic amine A2 methyl methyl methyl methyl methyl methyl Aromatic amine A3 methyl Methoxy methyl methyl Methoxy methyl Aromatic amine A4 Isopropyl Methoxy Isopropyl Isopropyl Methoxy Isopropyl Aromatic amine A5 Isopropyl Tert-butyl Isopropyl Isopropyl Tert-butyl Isopropyl Aromatic amine A6 methyl Tert-butyl methyl methyl Tert-butyl methyl Aromatic amine A7 hydrogen Tert-butyl hydrogen hydrogen Tert-butyl hydrogen Aromatic amine A8 methyl Methoxy Tert-butyl methyl Methoxy Tert-butyl Aromatic amine A9 methyl Dimethylamino methyl methyl Dimethylamino methyl Aromatic amine A10 hydrogen Dimethylamino hydrogen hydrogen Dimethylamino hydrogen Aromatic amine A11 methyl Diethylamino methyl methyl Diethylamino methyl Aromatic amine A12 methyl Diisopropylamino Isopropyl methyl Diisopropylamino Isopropyl

[0020] In a further example of the present invention, the structure of the ligand contained in the nickel-monodentate phosphite ligand catalyst is optimized. Optionally, the structure of the monodentate phosphite ligand is:

[0021]

[0022] Among them, R 1 , R 2 and R 3 The groups include any one of hydrogen, methyl, ethyl, isopropyl, tert-butyl, and methoxy.

[0023] In a further example of the present invention, the ratio of the nickel-monodentate phosphite ligand catalyst to the aromatic amine in the hydrocyanation reaction method is explored and optimized. Optionally, the mass ratio of the nickel-monodentate phosphite ligand catalyst to the aromatic amine is 1:(0.05-0.8), and further 1:(0.1-0.6) is optional, which is conducive to the effective coordination of the aromatic amine and the active nickel intermediate during the hydrocyanation reaction method, and improves the stability of the catalyst.

[0024] In a further example of the present invention, the hydrocyanation reaction method is a hydrocyanation reaction method for preparing adiponitrile.

[0025] Furthermore, the hydrocyanation reaction method includes a one-step hydrocyanation reaction method for preparing pentenenitrile using butadiene as a raw material.

[0026] Furthermore, the reaction temperature of the one-step hydrocyanation reaction method is 40-110°C, preferably 50-95°C. This temperature range is relatively mild, easy to control, and has strong process operability.

[0027] It should be noted that the pressure of the one-step hydrocyanation reaction method in the present invention is not limited and can be selected to be 1-5 bar.

[0028] Furthermore, the reaction time of the one-step hydrocyanation reaction method is 1-5 hours. Through the analysis of the embodiments and comparative examples, it can be seen that the technical solution of the present invention can significantly increase the reaction rate, shorten the reaction time, and improve the overall process production efficiency.

[0029] Furthermore, when the hydrocyanation reaction method is a one-step hydrocyanation reaction method, X in the structure of the aromatic amine 1 , X 3 , Y 1 , Y 3 The groups are selected from hydrogen or alkyl, X 2 , Y 2 The groups are each selected from alkyl or alkoxy groups.

[0030] Furthermore, in the one-step hydrocyanation reaction method, the mass ratio of the nickel-monodentate phosphite ligand catalyst to butadiene is (0.5-3):1000, preferably (0.75-2.5):1000. The present invention can significantly improve the stability of the catalyst during the one-step hydrocyanation reaction method and increase the reaction rate by adding a trace amount of a specific aromatic amine substance; after the reaction is completed, the aromatic amine can be separated through a separation and purification process, such as extraction, distillation or extractive distillation, and a high-purity pentenenitrile product can be obtained.

[0031] Furthermore, the hydrocyanation reaction method also includes a two-step hydrocyanation reaction method for preparing adiponitrile using pentenenitrile as a raw material.

[0032] Furthermore, the reaction temperature of the two-step hydrocyanation reaction method is 35-90°C, preferably 40-80°C. This temperature range is relatively mild and easy to control, and the overall process has strong operability.

[0033] It should be noted that the pressure of the two-step hydrocyanation reaction method in the present invention is not limited and can be selected to be 1-5 bar.

[0034] Furthermore, the reaction time of the one-step hydrocyanation reaction method is 1-10 hours. Through the analysis of the embodiments and comparative examples, it can be seen that the technical solution of the present invention can significantly increase the reaction rate, shorten the reaction time, and improve the overall process production efficiency.

[0035] Furthermore, in the two-step hydrocyanation reaction method, X in the structure of the aromatic amine 1 , X 3 , Y 1 , Y 3 The groups are selected from any one of hydrogen, alkyl or alkoxy, X 2 , Y 2 The groups are selected from alkoxy or alkylamino groups.

[0036] Furthermore, in the two-step hydrocyanation reaction method, the mass ratio of the nickel-monodentate phosphite ligand catalyst to pentenenitrile is (0.5-3):1000, preferably (0.75-2.5):1000. The present invention can significantly improve the stability of the catalyst during the one-step hydrocyanation reaction method and increase the reaction rate by adding a trace amount of a specific aromatic amine substance; after the reaction is completed, the aromatic amine can be separated by a separation and purification process, such as extraction, distillation or extractive distillation, and a high-purity adiponitrile product can be obtained. .

[0037] Furthermore, the two-step hydrocyanation reaction method is carried out with the participation of a co-catalyst, and the addition of the co-catalyst is beneficial to synergistically improving the stability and reaction rate of the catalyst; the co-catalyst includes one of zinc chloride, aluminum chloride, ferric chloride, titanium tetrachloride, and triphenylboron.

[0038] Furthermore, the mass ratio of the nickel-monodentate phosphite ligand catalyst to the co-catalyst is (0.2-0.8):1, preferably (0.3-0.7):1. By optimizing the dosage of the catalyst and the co-catalyst, the reaction rate can be synergistically optimized with the aromatic amine to reduce the occurrence of side reactions and improve the reaction efficiency.

[0039] Compared with the prior art, the beneficial effects of the present invention are as follows: the hydrocyanation reaction method of the present invention includes a nickel-monodentate phosphite ligand catalyst and an aromatic amine of a specific structure, which can not only catalytically shorten the time of the hydrocyanation reaction method, but also significantly reduce or eliminate the accumulation of ligand hydrolysis products and reduce the catalyst loss in the reaction. The hydrocyanation reaction method of the present invention has high reaction efficiency, stable catalyst performance, high raw material conversion rate and product selectivity, and can be used for the preparation process of large-scale butadiene direct hydrocyanation method for adiponitrile. DETAILED DESCRIPTION

[0040] In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively below, and preferred embodiments of the present invention are given. However, it should be understood that these embodiments are only used for more detailed description and should not be understood as limiting the present invention in any form, i.e., not intended to limit the scope of protection of the present invention.

[0041] Unless otherwise defined, the technical terms used in the following examples have the same meanings as those generally understood by those skilled in the art to which the present invention belongs. The test reagents used in the following examples, unless otherwise specified, are all conventional biochemical reagents; the experimental methods, unless otherwise specified, are all conventional methods.

[0042] It should be noted that in the nickel-monodentate phosphite ligand catalyst described in the present invention, the coordination number of nickel is 4 or 6, generally 4; the present invention aims to solve the technical problem of catalyst instability during the hydrocyanation reaction method in the prior art, so the embodiment of this application will no longer describe the ratio of the number of each nickel and the monodentate phosphite ligand.

[0043] In the embodiment of the present invention, the conversion rate of the hydrocyanation reaction method is calculated using the percentage of gas chromatography peak area, for example: the conversion rate of the one-step hydrocyanation reaction method = (2M3BN + 3PN) / (2M3BN + 3PN + butadiene) × 100%, 3PN selectivity = 3PN / (2M3BN + 3PN) × 100%; the conversion rate of the two-step hydrocyanation reaction method = (ADN + MGN) / (ADN + MGN + 3PN) × 100%, ADN selectivity = ADN / (ADN + MGN) × 100%; the content of the catalyst in the reaction system can be characterized by the Ni content in the clear liquid.

[0044] Example 1

[0045] A one-step hydrocyanation reaction method, which uses butadiene as a raw material to prepare pentenenitriles in a reaction system containing aromatic amines under the action of a nickel-monodentate phosphite ligand catalyst, specifically:

[0046] (1) Material preparation: The catalyst used in this embodiment is nickel-tris(2-ethylphenyl) phosphite catalyst, and its preparation method can be selected to include the following steps: ① Synthesis of tris(2-ethylphenyl) phosphite ligand: Under a nitrogen atmosphere, 2-ethylphenol (73.2 g, 0.6 mol) was added to a 250 mL round-bottom flask, and phosphorus trichloride (27.4 g, 0.2 mol) was added dropwise at room temperature. A large amount of HCl byproduct was generated during the reaction and absorbed by alkali solution; after the addition was completed, the mixture was stirred at room temperature for 1 h, and then slowly heated to 150° C. until no HCl escaped; the reactant was then purified by high vacuum distillation to obtain a product with a purity of more than 9 9% product, yield 98%; the product was characterized by 31P NMR and mass spectrometry, confirming that the target structure was tris(2-ethylphenyl) phosphite; ② Synthesis of nickel-tris(2-ethylphenyl) phosphite catalyst: tris(2-ethylphenyl) phosphite, nickel powder and 3-pentenenitrile were added to a round-bottom flask equipped with a mechanical stirrer, and kept under nitrogen atmosphere at about 110° C. with continuous stirring for about 24 hours; after the reaction was completed, the unreacted nickel powder in the reacted material was filtered out in a nitrogen atmosphere to obtain the nickel-tris(2-ethylphenyl) phosphite catalyst containing 79% tris(2-ethylphenyl) phosphite, 19% pentenenitrile and 2% nickel.

[0047] It should be noted that the nickel powder mentioned in the embodiments of the invention is nickel powder that can be purchased commercially. In addition, the preparation process of the ligand and the preparation process of the nickel-monodentate phosphite ligand catalyst in the embodiments of the present invention are only preferred demonstrations. Those skilled in the art can select other methods to prepare the ligand or the nickel-monodentate phosphite ligand catalyst through non-creative labor, and under certain working conditions, the ligand or the nickel-monodentate phosphite ligand catalyst of the appropriate type can be directly purchased based on the technical solution of the present invention, and the protection scope of the present invention is not limited thereby.

[0048] (2) One-step hydrocyanation reaction method: Nickel-tri(2-ethylphenyl)phosphite catalyst (1.5 mmol), aromatic amine A1 (0.9 mmol) and butadiene (2.0 mol) were placed in a stainless steel reactor. After replacing with nitrogen, the reaction system was heated to 50°C. Then, hydrocyanic acid (1.9 mol) was slowly added to the reactor using a pump for 2 h. After the addition was completed, the reaction was continued at 50°C. As the reaction proceeded, samples were obtained from the reactor at different times and analyzed. The results are shown in Table 2.

[0049] Table 2

[0050] Reaction time / h Butadiene / wt% 3PN / wt% 2M3BN / wt% Clear liquid Ni / ppm Conversion rate / % 3PN selectivity / % 1 54.65 29.95 15.40 339 45.35 66.04 2 44.25 37.05 18.70 334 55.75 66.46 3 34.75 43.36 21.89 329 65.25 66.45 4 25.05 49.56 25.39 330 74.95 66.12 5 14.45 56.67 28.88 328 85.55 66.24

[0051] Example 2

[0052] A one-step hydrocyanation reaction method, which uses butadiene as a raw material to prepare pentenenitriles in a reaction system containing aromatic amines under the action of a nickel-monodentate phosphite ligand catalyst, specifically:

[0053] (1) Material preparation: The catalyst used in this example is nickel-tris(2-isopropyl-4-methoxyphenyl) phosphite catalyst, which is prepared by the coordination and complexation of commercially available tris(2-isopropyl-4-methoxyphenyl) phosphite and nickel powder: tris(2-isopropyl-4-methoxyphenyl) phosphite, nickel powder and 3-pentenenitrile are added to a round-bottom flask equipped with a mechanical stirrer, and stirred continuously at about 120° C. for about 24 hours under a nitrogen atmosphere; after the reaction is completed, the unreacted nickel powder in the reacted material is filtered out in a nitrogen atmosphere to obtain the nickel-tris(2-isopropyl-4-methoxyphenyl) phosphite catalyst containing 81% tris(2-isopropyl-4-methoxyphenyl) phosphite, 17% pentenenitrile and 2% nickel.

[0054] (2) One-step hydrocyanation reaction method: Nickel-tri(2-isopropyl-4-methoxyphenyl)phosphite catalyst (2.5 mmol), aromatic amine A3 (0.25 mmol) and butadiene (1.0 mol) were placed in a stainless steel reactor. After replacing with nitrogen, the reaction system was heated to 95°C. Then, hydrocyanic acid (0.95 mol) was slowly added to the reactor using a pump for 2 h. After the addition was completed, the reaction was continued at 95°C. As the reaction proceeded, samples were obtained from the reactor at different times and analyzed. The results are shown in Table 3.

[0055] Table 3

[0056] Reaction time / h Butadiene / wt% 3PN / wt% 2M3BN / wt% Clear liquid Ni / ppm Conversion rate / % 3PN selectivity / % 1 56.15 29.65 14.20 324 43.85 67.62 2 45.53 36.65 17.82 330 54.47 67.28 3 35.25 43.36 21.39 319 64.75 66.97 4 26.25 49.56 24.19 325 73.75 67.20 5 15.56 56.67 27.77 327 84.44 67.11

[0057] Example 3

[0058] Based on the one-step hydrocyanation reaction method shown in Example 1, the catalyst, raw materials and control parameters used in this embodiment are the same as those in Example 1, except that the aromatic amine added during the one-step hydrocyanation reaction method of this embodiment is aromatic amine A9; by sampling the reaction system at different times for analysis, the reaction results are shown in Table 4.

[0059] Table 4

[0060] Reaction time / h Butadiene / wt% 3PN / wt% 2M3BN / wt% Clear liquid Ni / ppm Conversion rate / % 3PN selectivity / % 1 65.25 23.24 11.51 338 34.75 66.88 2 55.16 30.01 14.83 330 44.84 66.93 3 44.37 37.19 18.44 323 55.63 66.85 4 36.09 43.03 20.88 316 63.91 67.33 5 25.01 50.65 24.34 305 74.99 67.54

[0061] Combining Table 2 and Table 4, the effect of the one-step hydrocyanation reaction method containing A1 aromatic amine is relatively better than the effect of the hydrocyanation reaction method containing A9 aromatic amine. In the actual reaction process, suitable aromatic amines can be selected according to specific working conditions to catalyze the one-step hydrocyanation reaction method.

[0062] Example 4

[0063] A two-step hydrocyanation reaction method, in which pentenenitrile is used as a raw material to prepare adiponitrile in a reaction system containing aromatic amines under the action of a nickel-monodentate phosphite ligand catalyst, specifically:

[0064] This example uses the nickel-tris(2-ethylphenyl)phosphite catalyst shown in Example 1, and places the catalyst (5 mmol), anhydrous zinc chloride (16 mmol), aromatic amine A9 (0.5 mmol) and 3PN (2.0 mol) in a stainless steel reactor. After replacing with nitrogen, the reaction system is heated to 40°C; then, hydrocyanic acid (1.9 mol) is slowly added to the reactor with a pump, and the addition time lasts for 2 hours; after the addition is completed, the reaction is continued at 40°C; as the reaction proceeds, samples are obtained from the reactor at different times and analyzed, and the results are shown in Table 5.

[0065] Table 5

[0066] Reaction time / h 3PN / wt% ADN / wt% MGN / wt% Clear liquid Ni / ppm Conversion rate / % ADN selectivity / % 2 75.90 19.81 4.29 340 24.10 82.20 4 63.02 30.45 6.53 336 36.98 82.34 6 51.98 39.55 8.47 330 48.02 82.36 8 38.87 50.24 10.89 327 61.13 82.19 10 26.65 60.42 12.93 324 73.35 82.37

[0067] Example 5

[0068] A two-step hydrocyanation reaction method, in which pentenenitrile is used as a raw material to prepare adiponitrile in a reaction system containing aromatic amines under the action of a nickel-monodentate phosphite ligand catalyst, specifically:

[0069] This example uses the nickel-tris(2-isopropyl-4-methoxyphenyl)phosphite catalyst shown in Example 2, and places the catalyst (0.6 mmol), anhydrous titanium tetrachloride (0.9 mmol), aromatic amine A11 (0.36 mmol) and 3PN (0.8 mol) in a stainless steel reactor. After replacing with nitrogen, the reaction system is heated to 80°C; then, hydrocyanic acid (0.76 mol) is slowly added to the reactor with a pump, and the feeding time lasts for 2 hours; after the feeding is completed, the reaction is continued at 80°C; as the reaction proceeds, samples are obtained from the reactor at different times and analyzed, and the results are shown in Table 6.

[0070] Table 6

[0071] Reaction time / h 3PN / wt% ADN / wt% MGN / wt% Clear liquid Ni / ppm Conversion rate / % ADN selectivity / % 2 74.90 20.65 4.45 340 25.10 82.27 4 62.03 31.14 6.83 335 37.97 82.01 6 50.01 41.06 8.93 332 49.99 82.14 8 34.65 53.74 11.61 329 65.35 82.23 10 22.34 63.34 14.32 326 77.66 81.56

[0072] Example 6

[0073] Based on the two-step hydrocyanation reaction method shown in Example 4, the catalyst, raw materials and control parameters used in this example are the same as those in Example 4, except that the aromatic amine added during the two-step hydrocyanation reaction method of this example is aromatic amine A1; by sampling the reaction system at different times for analysis, the reaction results are shown in Table 7.

[0074] Table 7

[0075] Reaction time / h 3PN / wt% ADN / wt% MGN / wt% Clear liquid Ni / ppm Conversion rate / % ADN selectivity / % 2 80.60 15.91 3.49 340 19.40 82.01 4 68.23 26.21 5.56 322 31.77 82.50 6 56.01 35.91 8.08 313 43.99 81.63 8 43.25 46.65 10.10 302 56.75 82.20 10 31.22 56.89 11.89 292 68.78 82.71

[0076] Combining Table 5 and Table 7, the effect of the two-step hydrocyanation reaction method containing A9 aromatic amine is relatively better than the effect of the hydrocyanation reaction method containing A1 aromatic amine. In the actual reaction process, suitable aromatic amines can be selected according to specific working conditions to catalyze the two-step hydrocyanation reaction method.

[0077] Comparative Example 1

[0078] Based on the one-step hydrocyanation reaction method shown in Example 1, the catalyst, raw materials and control parameters used in this comparative example are the same as those in Example 1, except that no aromatic amine is added during the one-step hydrocyanation reaction method of this comparative example; by sampling the reaction system at different times for analysis, the reaction results are shown in Table 8.

[0079] Table 8

[0080] Reaction time / h Butadiene / wt% 3PN / wt% 2M3BN / wt% Clear liquid Ni / ppm Conversion rate / % 3PN selectivity / % 1 84.65 10.23 5.12 338 15.35 66.64 2 71.25 19.45 9.30 315 28.75 67.65 3 58.35 27.65 14.00 285 41.65 66.39 4 49.15 34.13 16.72 254 50.85 67.12 5 37.25 41.56 21.19 229 62.75 66.23

[0081] Based on Table 2 and Table 8, it can be confirmed that after the same reaction time, the raw material conversion rate of the reaction system of Example 1 in which aromatic amine A1 is added to the one-step hydrocyanation reaction method system is higher, and the Ni content in the clear liquid is also higher. When the reaction time reaches 5h, the Ni content of the clear liquid in the reaction system of Comparative Example 1 without using aromatic amine is reduced to 68% of the original, and the butadiene conversion rate is 62.75%, while the Ni content of the clear liquid of the reaction system of Example 1 remains at 97% of the original, and the butadiene conversion rate reaches 85.55%, which verifies that the present invention comprising a nickel-monodentate phosphite ligand catalyst and a specific structure aromatic amine can significantly improve the reaction rate of the one-step hydrocyanation reaction method and reduce the loss of the catalyst.

[0082] Comparative Example 2

[0083] Based on the two-step hydrocyanation reaction method shown in Example 4, the catalyst, raw materials and control parameters used in this comparative example are the same as those in Example 4, except that no aromatic amine is added during the two-step hydrocyanation reaction method of this comparative example; by sampling the reaction system at different times for analysis, the reaction results are shown in Table 9.

[0084] Table 9

[0085] Reaction time / h 3PN / wt% ADN / wt% MGN / wt% Clear liquid Ni / ppm Conversion rate / % ADN selectivity / % 2 85.60 11.81 2.59 340 14.40 82.01 4 73.24 22.12 4.64 312 26.76 82.66 6 61.98 31.25 6.77 281 38.02 82.19 8 49.15 41.89 8.96 252 50.85 82.38 10 37.75 51.32 10.93 224 62.25 82.44

[0086] By comparing Table 5 and Table 9, it can be confirmed that after the same reaction time, the 3PN conversion rate of the reaction system of Example 3 in which aromatic amine A9 is added to the two-step hydrocyanation reaction method system is higher, and the Ni content in the clear liquid is also higher. When the reaction time reaches 10h, the Ni content of the clear liquid in the reaction system of Comparative Example 3 without using aromatic amine is reduced to 66% of the original, and the butadiene conversion rate is 62.25%, while the Ni content of the clear liquid of the reaction system of Example 3 remains at 95% of the original, and the butadiene conversion rate reaches 73.35%, which verifies that the present invention contains a nickel-monodentate phosphite ligand catalyst and a specific structure aromatic amine can significantly improve the reaction rate of the two-step hydrocyanation reaction method, while reducing the loss of the catalyst.

[0087] Comparative Example 3

[0088] A two-step hydrocyanation reaction method, in which pentenenitrile is used as a raw material to prepare adiponitrile. In this comparative example, the nickel-tris(2-ethylphenyl)phosphite catalyst shown in Example 1 is used. In the specific preparation process, the catalyst (5 mmol), anhydrous zinc chloride (16 mmol) and 3PN (2.0 mol) are placed in a stainless steel reactor, and the following aromatic amine containing one aromatic ring is added:

[0089]

[0090] The relevant parameters and control conditions of this comparative example are the same as those of Example 4; samples of the reaction system were taken at different times for analysis, and the results are shown in Table 10.

[0091] Table 10

[0092] Reaction time / h 3PN / wt% ADN / wt% MGN / wt% Clear liquid Ni / ppm Conversion rate / % ADN selectivity / % 2 81.36 15.33 3.31 340 18.64 82.24 4 69.45 25.11 5.44 325 30.55 82.19 6 57.13 35.21 7.66 317 42.87 82.13 8 44.35 45.72 9.93 309 55.65 82.16 10 33.25 54.98 11.77 295 66.75 82.37

[0093] Comparative Example 4

[0094] A two-step hydrocyanation reaction method, in which pentenenitrile is used as a raw material to prepare adiponitrile. In this comparative example, the nickel-tris(2-ethylphenyl)phosphite catalyst shown in Example 1 is used. In the specific preparation process, the catalyst (5 mmol), anhydrous zinc chloride (16 mmol) and 3PN (2.0 mol) are placed in a stainless steel reactor, and the following aromatic amine containing three aromatic rings is added:

[0095]

[0096] The relevant parameters and control conditions of this comparative example are the same as those of Example 4; samples of the reaction system were taken at different times for analysis, and the results are shown in Table 11.

[0097] Table 11

[0098] Reaction time / h 3PN / wt% ADN / wt% MGN / wt% Clear liquid Ni / ppm Conversion rate / % ADN selectivity / % 2 79.59 16.87 3.54 340 20.41 82.66 4 69.23 25.31 5.46 328 30.77 82.26 6 57.24 35.09 7.67 319 42.76 82.06 8 45.06 45.35 9.59 318 54.94 82.54 10 34.15 54.18 11.67 301 65.85 82.28

[0099] Combining Table 5, Table 10 and Table 11, it can be verified that the conversion rate and stability of the catalyzed hydrocyanation reaction method using the hydrocyanation reaction method of the present invention containing a specific structure aromatic amine with two aromatic rings are better than the hydrocyanation reaction method catalyzed by an aromatic amine containing one aromatic ring or three aromatic rings. It is speculated that the aromatic amine with a specific structure containing two aromatic rings in the present invention can provide suitable steric hindrance to promote the catalytic activity of the catalyst; at the same time, the electron-pushing group in the aromatic amine contained in the hydrocyanation reaction method of the present invention has a more obvious electronic effect, which can enhance the complexation between the N atom and the active nickel intermediate and enhance the protection of the catalyst; through the coordinated optimization of the steric effect and the electronic effect, the conversion rate, product selectivity and catalyst stability of the hydrocyanation reaction method of the present invention are improved.

[0100] It should be noted that the above contents are further detailed descriptions of the present invention in combination with specific implementation methods, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions; the dimensional data of this embodiment does not limit the technical solution, but only shows one of the specific working conditions. For ordinary technicians in the technical field to which the present invention belongs, several simple improvements and modifications can be made without departing from the concept of the present invention, which should be regarded as falling within the scope of protection of the present invention.

Claims

1. A hydrocyanation reaction method, characterized in that: The hydrocyanation reaction method is carried out in a reaction system containing an aromatic amine under the action of a nickel-monodentate phosphite ligand catalyst, wherein the structure of the aromatic amine is: Among them, X 1 -X 3 Group and Y 1 -Y 3 The groups include any one of hydrogen, alkyl, alkoxy, alkylamino, hydroxyl, and amino.

2. The hydrocyanation reaction method according to claim 1, characterized in that: The structural formula of the alkyl group is -R, and the structural formula of the alkoxy group is The structural formula of the alkylamino group is Wherein, the R group includes any one of methyl, ethyl, isopropyl and tert-butyl.

3. The hydrocyanation reaction method according to claim 1, characterized in that: The structure of the monodentate phosphite ligand is: Among them, R 1 , R 2 and R 3 The groups include any one of hydrogen, methyl, ethyl, isopropyl, tert-butyl, and methoxy.

4. The hydrocyanation reaction method according to claim 1, characterized in that: The mass ratio of the nickel-monodentate phosphite ligand catalyst to the aromatic amine is 1:(0.05-0.8), preferably 1:(0.1-0.6).

5. The hydrocyanation reaction method according to any one of claims 1 to 4, characterized in that: The hydrocyanation reaction method is a hydrocyanation reaction method for preparing adiponitrile.

6. The hydrocyanation reaction method according to claim 5, characterized in that: The hydrocyanation reaction method includes a one-step hydrocyanation reaction method for preparing pentenenitrile using butadiene as a raw material; Preferably, the reaction temperature of the one-step hydrocyanation method is 40-110°C, preferably 50-95°C.

7. The hydrocyanation reaction method according to claim 6, characterized in that: In the one-step hydrocyanation reaction method, X in the structure of the aromatic amine 1 , X 3 , Y 1 , Y 3 The groups are selected from hydrogen or alkyl, X 2 , Y 2 The groups are selected from alkyl or alkoxy groups; And / or, in the one-step hydrocyanation reaction method, the mass ratio of the nickel-monodentate phosphite ligand catalyst to butadiene is (0.5-3):1000, preferably (0.75-2.5):1000.

8. The hydrocyanation reaction method according to claim 5, characterized in that: The hydrocyanation reaction method also includes a two-step hydrocyanation reaction method for preparing adiponitrile using pentenenitrile as a raw material; Preferably, the reaction temperature of the two-step hydrocyanation method is 35-90°C, preferably 40-80°C.

9. The hydrocyanation reaction method according to claim 8, characterized in that: In the two-step hydrocyanation reaction method, X in the structure of the aromatic amine 1 , X 3 , Y 1 , Y 3 The groups are selected from any one of hydrogen, alkyl or alkoxy, X 2 , Y 2 The groups are selected from alkoxy or alkylamino groups; And / or, in the two-step hydrocyanation reaction method, the mass ratio of the nickel-monodentate phosphite ligand catalyst to pentenenitrile is (0.5-3):1000, preferably (0.75-2.5):1000.

10. The hydrocyanation reaction method according to claim 8, characterized in that: The two-step hydrocyanation reaction method is carried out in the presence of a co-catalyst, wherein the co-catalyst comprises at least one of zinc chloride, aluminum chloride, ferric chloride, titanium tetrachloride, and triphenylboron; Preferably, the mass ratio of the nickel-monodentate phosphite ligand catalyst to the co-catalyst is (0.2-0.8):1, preferably (0.3-0.7):1.

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