Hydrocyanation reaction method

Abstract

The present invention provides a hydrocyanation reaction method. The hydrocyanation reaction method is carried out in a reaction system containing an aromatic amine under the action of a nickel–bidentate phosphite ligand catalyst, and the structure of the aromatic amine is (I): the X1-X3 groups and the Y1-Y3 groups each independently comprising any one of hydrogen, an alkyl group, an alkoxy group, an alkylamino group, a hydroxyl group, and an amino group. The hydrocyanation reaction method of the present invention not only has high reaction efficiency, but can also significantly reduce or eliminate the accumulation of ligand hydrolysis products, and stabilize the effective content of the catalyst in the reaction system; in addition, the hydrocyanation reaction method of the present invention has high reaction efficiency, few side reactions, and a high raw material conversion rate and product selectivity, and can meet the requirements of a large-scale production process for adiponitrile by a method of direct hydrocyanation of butadiene.

Description

Hydrocyanation process TECHNICAL FIELD

[0001] The present application relates to the technical field of chemical synthesis, in particular to a hydrocyanation reaction method. BACKGROUND

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

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

[0004] The specific reaction steps include: one-step hydrocyanation reaction, butadiene undergoes addition with hydrocyanic acid (HCN) in the presence of a nickel catalyst to form 2-methyl-3-butenenitrile (2M3BN) and 3-pentenenitrile (3PN); 2M3BN isomerization reaction, 2M3BN undergoes isomerization reaction in the presence of a nickel catalyst to convert to 3PN; two-step hydrocyanation reaction, 3PN is isomerized to 4-pentenenitrile (4PN), which then undergoes addition with HCN to form ADN and byproduct 2-methylglutaronitrile (MGN). This step requires a nickel catalyst and a Lewis acid additive and has a high requirement for catalyst activity, which is the key step in the entire reaction.

[0005] 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:

[0006] Among them, the zero-valent nickel-phosphorus catalyst [NiL4] (L is a ligand) removes one molecule of ligand to form [NiL3], which then combines with HCN to form [HNiL3CN]; it continues to lose one molecule of ligand to form [HNiL2CN], which then combines with butadiene to form the intermediate [C4H6-HNiL2CN]. This intermediate can react along two paths to form 3PN and 2M3BN, respectively, and regenerate [NiL3] to continue participating in the catalytic cycle reaction.

[0007] However, in actual production, there are many difficulties. Firstly, the presence of water in the reaction system may cause hydrolysis of the phosphite ligand of the nickel catalyst, producing acidic hydrolysis products, further accelerating the hydrolysis of the ligand, and gradually causing the deactivation of the nickel-bidentate phosphite ligand catalyst; secondly, when the HCN concentration in the reaction system is high, it will attack the active nickel ([NiL3] and [NiL2]) of the hydrocyanation reaction to generate nickel cyanide (Ni(CN)2) precipitate, causing catalyst deactivation; thirdly, the hydrocyanation reaction (especially the two-step hydrocyanation reaction) is slow, the residence time is long, and the catalyst deactivation amount is high. In addition, the occurrence of side reactions in the hydrocyanation reaction (such as a large amount of 2-methyl glutaronitrile as a byproduct of the two-step hydrocyanation reaction) limits the downstream application, not only reduces the reaction efficiency, but also increases the production cost.

[0008] Therefore, it is a technical problem to be solved to develop a hydrocyanation reaction process with high reaction efficiency, high catalyst stability and high product selectivity. SUMMARY

[0009] In view of the deficiencies in the prior art, the present application discloses a hydrocyanation reaction, which comprises a specific nickel-bidentate phosphite ligand catalyst and aromatic amine for catalyzing the hydrocyanation reaction, which can improve the raw material conversion rate and product selectivity, reduce the occurrence of side reactions, and significantly reduce the catalyst consumption and improve the stability of the overall process.

[0010] In order to achieve the above technical purposes, on the one hand, the present application provides a hydrocyanation reaction, which is carried out in a reaction system containing aromatic amine under the action of a nickel-bidentate phosphite ligand catalyst, and the structure of the aromatic amine is:

[0011] Among them, X 1 -X 3 group and Y 1 -Y 3 group respectively includes any one of hydrogen, alkyl, alkoxy, alkylamine, hydroxyl, amino.

[0012] The technical solution adopts a nickel-bidentate phosphite ligand as a catalyst. In the hydrocyanation reaction, the bidentate phosphite ligand has weaker complexation with the metal nickel than the traditional monodentate phosphite ligand, is easy to be free and thus generates an active nickel intermediate to promote the occurrence of the hydrocyanation reaction. However, at the same time, the active nickel intermediate (such as [NiL3] and [NiL2]) is in a naked state due to the partial loss of the ligand and is easy to be attacked by a polar molecule such as hydrocyanic acid and water, thus generating nickel cyanide and a hydrolysis product, causing catalyst loss. The compound used in the technical solution has strong complexation with the metal nickel and can coordinate with the active nickel intermediate in the reaction in time, thus protecting the active nickel intermediate and reducing catalyst loss.

[0013] Therefore, the hydrocyanation reaction of the present application can reduce catalyst loss, reduce byproduct generation and efficiently catalyze the hydrocyanation reaction by the synergistic optimization of the nickel-bidentate phosphite ligand catalyst and the aromatic amine.

[0014] In further examples of the present application, the structure of X 1 -X 3 and Y 1 -Y 3 is optimized. Optionally, the structure of the alkyl group is -R, the structure of the alkoxy group is and the structure of the alkylamine group is wherein the R group includes any one of a methyl group, an ethyl group, an isopropyl group and a tert-butyl group.

[0015] In some optional examples of the present application, the aromatic amine can be selected from any one in Table 1.

[0016] Table 1

[0017] In further examples of the present application, the structure of the ligand used in the nickel-bidentate phosphite ligand catalyst is optimized. Optionally, the structure of the ligand used in the nickel-bidentate phosphite ligand catalyst is:

[0018] wherein R 1 -R 4 and Z 1 -Z 5 include any one of hydrogen, a methyl group, an ethyl group, an isopropyl group, a tert-butyl group and a methoxy group. In the specific process, a person skilled in the art can select a suitable bidentate phosphite ligand according to the needs.

[0019] In further examples of the present application, the ratio of the nickel-bidentate phosphite ligand catalyst to the aromatic amine in the hydrocyanation reaction is optimized. Optionally, the mass ratio of the nickel-bidentate phosphite ligand catalyst to the aromatic amine is 1:(0.05-0.8), further optionally 1:(0.1-0.6), which is conducive to the effective coordination of the aromatic amine and the active nickel intermediate during the hydrocyanation reaction, and improves the stability of the catalyst.

[0020] In further examples of the present application, the ratio of the nickel-bidentate phosphite ligand catalyst to the aromatic amine in the hydrocyanation reaction is optimized. Optionally, the mass ratio of the nickel-bidentate phosphite ligand catalyst to the aromatic amine is 1:(0.05-0.8), further optionally 1:(0.1-0.6), which is conducive to the effective coordination of the aromatic amine and the active nickel intermediate during the hydrocyanation reaction, and improves the stability of the catalyst.

[0021] In further examples of the present application, the hydrocyanation reaction method is a hydrocyanation reaction method for preparing adiponitrile.

[0022] Further, the hydrocyanation reaction method includes a one-step hydrocyanation reaction method for preparing pentenenitrile using butadiene as a raw material.

[0023] Further, the one-step hydrocyanation reaction method has a reaction temperature of 40-110°C, preferably 50-95°C, which is a relatively mild temperature range, easy to control, and has strong process operability.

[0024] It should be noted that the pressure in the one-step hydrocyanation reaction method in the present application is not limited, and can be 1-5 bar.

[0025] Further, the one-step hydrocyanation reaction method has a reaction time of 1-5 h. Through analysis of the examples and comparative examples, it can be seen that the technical solution of the present application can significantly improve the reaction rate, shorten the reaction time, and improve the overall process production efficiency.

[0026] Further, when the hydrocyanation reaction method is a one-step hydrocyanation reaction method, the X 1 , X 3 , Y 1 , Y 3 group in the structure of the aromatic amine is selected from hydrogen or an alkyl group, and the X 2 , Y 2 group is selected from an alkyl group or an alkoxy group.

[0027] Further, the mass ratio of the nickel-bidentate phosphite ligand catalyst to butadiene in the one-step hydrocyanation reaction method is (0.5-3):1000, preferably (0.75-2.5):1000, and the stability of the catalyst in the one-step hydrocyanation reaction method can be significantly improved by adding a small amount of the specific aromatic amine, and the reaction rate is also improved; after the reaction is completed, the aromatic amine can be separated by a separation and purification process such as extraction, rectification or extraction rectification, and a high-purity pentenenitrile product is obtained.

[0028] Further, the hydrocyanation reaction method further comprises a two-step hydrocyanation reaction method for preparing adiponitrile from pentenenitrile.

[0029] Further, the reaction temperature of the two-step hydrocyanation reaction method is 35-90°C, preferably 40-80°C, which is a relatively mild temperature range, easy to control, and the overall process has strong operability.

[0030] It should be noted that the pressure in the two-step hydrocyanation reaction method in the present application is not limited, and can be selected as 1-5 bar.

[0031] Further, the reaction time of the one-step hydrocyanation reaction method is 1-10h, and it can be seen from the examples and comparative examples that the technical scheme of the present application can significantly improve the reaction rate, shorten the reaction time, and improve the overall process production efficiency.

[0032] Further, in the two-step hydrocyanation reaction method, the X 1 , X 3 , Y 1 , Y 3 groups in the structure of the aromatic amine are selected from any one of hydrogen, alkyl or alkoxy, and the X 2 , Y 2 groups are selected from alkoxy or alkylamine.

[0033] Further, the mass ratio of the nickel-bidentate phosphite ligand catalyst to butadiene in the one-step hydrocyanation reaction method is (0.5-3):1000, preferably (0.75-2.5):1000, and the stability of the catalyst in the one-step hydrocyanation reaction method can be significantly improved by adding a small amount of the specific aromatic amine, and the reaction rate is also improved; after the reaction is completed, the aromatic amine can be separated by a separation and purification process such as extraction, rectification or extraction rectification, and a high-purity pentenenitrile product is obtained.

[0034] Further, the two-step hydrocyanation reaction method is carried out in the presence of a co-catalyst, and the addition of the co-catalyst is beneficial to synergistically improve the stability of the catalyst and the reaction rate; the co-catalyst includes one of zinc chloride, aluminum chloride, iron chloride, titanium tetrachloride and triphenylboron.

[0035] Further, the mass ratio of the nickel-bidentate phosphite ligand catalyst to the co-catalyst is (0.2-0.8):1, preferably (0.3-0.7):1, and the optimization of the catalyst and the co-catalyst dosage can be synergistically optimized with the aromatic amine to improve the reaction rate, reduce the occurrence of side reactions, and improve the reaction efficiency.

[0036] Compared with the prior art, the hydrogen cyanide reaction method of the present application includes a nickel-bidentate phosphite ligand catalyst and an aromatic amine with a specific structure, which can not only reduce the reaction time of the catalyzed hydrogen cyanide reaction method, but also significantly reduce or eliminate the accumulation of ligand hydrolysis products, stabilize the effective content of the catalyst in the reaction system; in addition, the hydrogen cyanide reaction method of the present application has high reaction efficiency, few side reactions, high raw material conversion rate and product selectivity, and can meet the needs of large-scale production process of butadiene direct hydrogen cyanide method for producing adiponitrile. BRIEF DESCRIPTION OF DRAWINGS

[0037] The drawings accompanying the specification of this application serve to provide further understanding of the present application, the illustrative embodiments of the present application and the description thereof serve to explain the present application, and do not constitute an improper limitation on the present application. In the drawings:

[0038] Figure 1 shows the gas chromatogram of the reaction of Example 5 of the present application at 2h. DETAILED DESCRIPTION

[0039] In order to facilitate the understanding of the present application, the present application will be described more fully below, and the preferred embodiments of the present application are given. It should be understood that these embodiments are only used for more detailed description, and should not be understood as limiting the present application in any form, i.e. not intended to limit the scope of protection of the present application.

[0040] Unless otherwise defined, the technical terms used in the following examples have the same meaning as generally understood by those skilled in the art to which the present application belongs. The test reagents used in the following examples, unless otherwise specified, are conventional biochemical reagents; the experimental methods, unless otherwise specified, are conventional methods.

[0041] It should be noted that in the present application, the coordination number of nickel and bidentate phosphite ligand in the nickel-bidentate phosphite ligand catalyst is generally 2 or 3, and is generally 2. The present application aims to solve the technical problem of instability of the catalyst in the hydrogen cyanide reaction method in the prior art, so the ratio of the number of nickel and bidentate phosphite ligand in the present application is not described again.

[0042] The conversion rate of the hydrocyanation reaction method was calculated using the peak area percentage of gas chromatography, wherein the conversion rate of the one-step hydrocyanation reaction method = (2M3BN + 3PN) / (2M3BN + 3PN + butadiene) x 100%, the 3PN selectivity = 3PN / (2M3BN + 3PN) x 100%; the conversion rate of the two-step hydrocyanation reaction method = (ADN + MGN) / (ADN + MGN + 3PN) x 100%, the ADN selectivity = ADN / (ADN + MGN) x 100%.

[0043] The content of the catalyst in the reaction system of the embodiment of the present application can be represented by the content of Ni in the clear solution.

[0044] Embodiment 1

[0045] A one-step hydrocyanation reaction method, which uses butadiene as a raw material to prepare pentenenitrile in a reaction system containing an aromatic amine under the catalysis of a nickel-bidentate phosphite ligand catalyst, specifically:

[0046] (1) Material preparation: The catalyst used in this embodiment is a nickel-bidentate phosphite ligand catalyst, wherein the structural formula of the bidentate phosphite ligand L21 is:

[0047] has the substituent structure shown in Table 2:

[0048] Table 2

[0049] The ligand L21 is prepared with nickel powder to obtain a nickel-bidentate phosphite ligand catalyst.

[0050] It should be noted that the nickel powder mentioned in the embodiment of the present application is commercially available nickel powder. In addition, the preparation process of the ligand and the preparation process of the nickel-bidentate phosphite ligand catalyst in the embodiment of the present application are only relatively optimal demonstrations, and those skilled in the art can select other ways to prepare the ligand or the nickel-bidentate phosphite ligand catalyst through non-creative labor, and in certain working conditions, the appropriate type of ligand or nickel-bidentate phosphite ligand catalyst can be directly purchased based on the technical solution of the present application, which does not limit the protection scope of the present application.

[0051] (2) One-step hydrocyanation reaction method: The nickel-bidentate phosphite ligand catalyst (2 mmol), aromatic amine A2 (1.0 mmol) and butadiene (2.0 mol) are placed in a stainless steel reaction kettle, and after replacement with nitrogen, the reaction system is heated to 50°C; then the hydrocyanic acid (1.9 mol) is slowly added into the kettle by pump, and the feeding time lasts for 2 h; after the feeding is completed, the reaction is continued at 50°C; as the reaction proceeds, the reaction system is sampled at different times for analysis, and the results are shown in Table 3.

[0052] Table 3

[0053] As can be verified from Table 3, in the one-step hydrocyanation reaction catalyzed by the nickel-bidentate phosphite ligand catalyst with the bidentate structure and the aromatic amine A2, the selectivity of 3PN reaches about 90%, and the side reaction is less; and the content of clear liquid Ni changes little during the reaction, which indicates that the performance of the catalyst is relatively stable during the reaction.

[0054] Example 2

[0055] A one-step hydrocyanation reaction method, which is used to prepare pentenenitrile by taking butadiene as a raw material in a reaction system containing an aromatic amine under the action of a nickel-bidentate phosphite ligand catalyst, specifically:

[0056] (1) Material preparation: The catalyst used in this example is a nickel-bidentate phosphite ligand catalyst, wherein the structural formula of the bidentate phosphite ligand L22 is the same as that of the ligand L21, but the ligand L22 has the substituent structure shown in Table 4:

[0057] Table 4

[0058] The ligand L22 is prepared into a nickel-bidentate phosphite ligand catalyst with nickel powder.

[0059] (2) One-step hydrocyanation reaction method: The nickel-bidentate phosphite ligand catalyst (5 mmol), the aromatic amine A4 (0.5 mmol) and butadiene (2.0 mol) are placed in a stainless steel reaction kettle, and after being replaced by nitrogen, the reaction system is heated to 95°C; then the hydrocyanic acid (1.9 mol) is slowly added into the kettle by a pump, and the feeding time lasts for 2 h; after the feeding is completed, the reaction is continued at 95°C; as the reaction proceeds, the reaction system is sampled at different times for analysis, and the results are shown in Table 5.

[0060] Table 5

[0061] As can be verified from Table 5, the raw material conversion rate and product selectivity of the one-step hydrocyanation reaction method catalyzed by the catalyst combination of the present application are high, the side reaction is less, and the retention rate of the catalyst is higher, and the catalytic performance is stable.

[0062] Example 3

[0063] A one-step hydrocyanation reaction method, which is used to prepare pentenenitrile by taking butadiene as a raw material in a reaction system containing an aromatic amine under the action of a nickel-bidentate phosphite ligand catalyst, specifically:

[0064] (1) Material preparation: the catalyst used in this example is a nickel-bidentate phosphite ligand catalyst, wherein the bidentate phosphite ligand L23 has the same structure as ligand L21, but ligand L23 has the substituent structure shown in Table 6:

[0065] Table 6

[0066] The ligand L23 is prepared with nickel powder to obtain a nickel-bidentate phosphite ligand catalyst.

[0067] (2) One-step hydrocyanation reaction method: the nickel-bidentate phosphite ligand catalyst (7.5 mmol), aromatic amine A5 (3.0 mmol) and butadiene (5.0 mol) are placed in a stainless steel reactor, which is replaced with nitrogen, and then the reaction system is heated to 75°C; then the hydrocyanic acid (1.9 mol) is slowly added into the reactor by pump, and the feeding time lasts for 2h; after the feeding is completed, the reaction is continued at 75°C; as the reaction proceeds, the reaction system is sampled at different times for analysis, and the results are shown in Table 7.

[0068] Table 7

[0069] As can be seen from Table 7, under the combined action of the nickel-bidentate phosphite ligand catalyst and the aromatic amine A5 catalyst in the one-step hydrocyanation reaction method, the selectivity of 3PN is about 90%, and the clear liquid Ni content changes little with time during the reaction, indicating that the catalyst is relatively stable during the reaction.

[0070] Example 4

[0071] A one-step hydrocyanation reaction method, the catalyst, reaction raw materials and control parameters used in the reaction are the same as in Example 1, the difference is that the aromatic amine added in this example is aromatic amine A11; as the reaction proceeds, the reaction system is sampled at different times for analysis, and the results are shown in Table 8.

[0072] Table 8

[0073] Combining Table 3 and Table 8, the effect of the one-step hydrocyanation reaction method containing aromatic amine A2 is relatively better than that of the one-step hydrocyanation reaction method containing A11 aromatic amine, and in the actual reaction process, the appropriate aromatic amine can be selected according to the specific working conditions for catalyzing the one-step hydrocyanation reaction method.

[0074] Example 5

[0075] A two-step hydrocyanation reaction method, which uses pentenenitrile as raw material to prepare adiponitrile in a reaction system containing aromatic amine under the action of a nickel-bidentate phosphite ligand catalyst, specifically:

[0076] (1) Material preparation: The catalyst used in this example is a nickel-bidentate phosphite ligand catalyst, wherein the bidentate phosphite ligand L24 has the same structural formula as ligand L21, but ligand L24 has the substituent structure shown in Table 9:

[0077] Table 9

[0078] The ligand L24 is prepared with nickel powder to obtain a nickel-bidentate phosphite ligand catalyst.

[0079] (2) Two-step hydrocyanation reaction method: The nickel-bidentate phosphite ligand catalyst (2 mmol), anhydrous zinc chloride (3 mmol), aromatic amine A11 (0.25 mmol), and 3PN (0.8 mol) are placed in a stainless steel reactor, which is replaced with nitrogen, and then the reaction system is heated to 80°C. Then, the hydrocyanic acid (0.76 mol) is slowly added to the reactor by pump, and the feeding time lasts for 2 h. After the feeding is completed, the reaction continues at 80°C. As the reaction proceeds, the reaction system is sampled at different times for analysis, and the results are shown in Table 10. Figure 1 shows the gas chromatogram at 2 h of this example.

[0080] Table 10

[0081] As can be verified from Table 10, in the two-step hydrocyanation reaction involving the nickel-bidentate phosphite ligand catalyst and aromatic amine A11, the selectivity of ADN reaches more than 96%, the side reactions are less, and the clear liquid Ni content changes little during the overall reaction process, indicating that the catalyst performance is relatively stable.

[0082] Example 6

[0083] A two-step hydrocyanation reaction method, which uses pentenenitrile as a raw material to prepare adiponitrile in a reaction system containing an aromatic amine under the action of a nickel-bidentate phosphite ligand catalyst, specifically:

[0084] (1) Material preparation: The catalyst used in this example is a nickel-bidentate phosphite ligand catalyst, wherein the bidentate phosphite ligand L25 has the same structural formula as ligand L21, but ligand L25 has the substituent structure shown in Table 11:

[0085] Table 11

[0086] The ligand L25 is prepared with nickel powder to obtain a nickel-bidentate phosphite ligand catalyst.

[0087] (2) Two-step hydrocyanation reaction method: the nickel-bidentate phosphite ligand catalyst (0.75 mmol), anhydrous titanium tetrachloride (2.5 mmol), aromatic amine A12 (0.45 mmol) and 3PN (1.0 mol) were placed in a stainless steel reactor, and after being replaced with nitrogen, the reaction system was heated to 40°C; then the hydrocyanic acid (0.95 mol) was slowly added into the reactor by pump, and the feeding time lasted for 2 h; after the feeding was completed, the reaction was continued at 40°C; as the reaction proceeded, the reaction system was sampled at different times for analysis, and the results are shown in Table 12.

[0088] Table 12

[0089] As can be seen from Table 12, the raw material conversion rate of the two-step hydrocyanation reaction method involving the nickel-bidentate phosphite ligand catalyst and aromatic amine A12 according to the present application can reach 95.7%, the selectivity of ADN can reach more than 96%, and the content of the catalyst is stable during the overall reaction process, and the stability of the catalyst is good.

[0090] Example 7

[0091] A two-step hydrocyanation reaction method, which uses pentenenitrile as a raw material to prepare adiponitrile in a reaction system containing an aromatic amine under the action of a nickel-bidentate phosphite ligand catalyst, specifically:

[0092] (1) Material preparation: the catalyst used in this example is a nickel-bidentate phosphite ligand catalyst, wherein the structural formula of the bidentate phosphite ligand L26 is the same as that of ligand L21, but the ligand L26 has the substituent structure shown in Table 13:

[0093] Table 13

[0094] The ligand L26 and nickel powder are used to prepare a nickel-bidentate phosphite ligand catalyst.

[0095] (2) Two-step hydrocyanation reaction method: the nickel-bidentate phosphite ligand catalyst (4.0 mmol), triphenylboron (8.0 mmol), aromatic amine A10 (2.0 mmol) and 3PN (2.0 mol) were placed in a stainless steel reactor, and after being replaced with nitrogen, the reaction system was heated to 60°C; then the hydrocyanic acid (1.95 mol) was slowly added into the reactor by pump, and the feeding time lasted for 2 h; after the feeding was completed, the reaction was continued at 60°C; as the reaction proceeded, the reaction system was sampled at different times for analysis, and the results are shown in Table 14.

[0096] Table 14

[0097] It can be verified from Table 14 that the selectivity of ADN in the two-step hydrocyanation reaction using the catalyst containing the nickel-bidentate phosphite ligand and the aromatic amine A10 can reach more than 96%, and the content of Ni in the clear solution does not decrease obviously during the reaction, which indicates that the catalytic performance of the catalyst is relatively stable during the reaction.

[0098] Example 8

[0099] A two-step hydrocyanation reaction method, the catalyst, reaction raw materials and control parameters used in the reaction are the same as those in Example 5, the difference is that the aromatic amine added in the present example is aromatic amine A2; with the progress of the reaction, the reaction system is sampled and analyzed at different times, and the results are shown in Table 15.

[0100] Table 15

[0101] It can be verified from Table 10 and Table 15 that compared with the two-step hydrocyanation reaction method using aromatic amine A2, the stability of the catalyst in the two-step hydrocyanation reaction method using aromatic amine A11 is higher, and the reaction rate is better, and in the actual reaction process, different aromatic amines can be selected for the catalytic two-step hydrocyanation reaction method according to the specific working conditions.

[0102] Comparative Example 1

[0103] A one-step hydrocyanation reaction method, the catalyst, reaction raw materials and control parameters used in the reaction are the same as those in Example 1, the difference is that no aromatic amine is added in the present comparative example; with the progress of the reaction, the reaction system is sampled and analyzed at different times, and the results are shown in Table 16.

[0104] Table 16

[0105] It can be verified from Table 3 and Table 16 that the one-step hydrocyanation reaction method of the present application contains a specific structure of aromatic amine, which makes the content of Ni in the clear solution of the catalytic one-step hydrocyanation reaction method more stable during the reaction, and compared with Example 1, the content of Ni in the clear solution in Comparative Example 1 decreases faster (the content of Ni in the clear solution decreases to 50% of the initial amount after 5h of reaction), which verifies that the aromatic amine A2 in the hydrocyanation reaction method of the present application has better effect in stabilizing the catalyst; in addition, the one-step hydrocyanation reaction method in Comparative Example 1 is slower than that in Example 1, which confirms that the aromatic amine A2 in the hydrocyanation reaction method of the present application has better effect in improving the reaction rate.

[0106] Comparative Example 2

[0107] A two-step hydrocyanation reaction method, the catalyst, reaction raw materials and control parameters used in the reaction are the same as those in Example 5, the difference is that no aromatic amine is added in the present comparative example; with the progress of the reaction, the reaction system is sampled and analyzed at different times, and the results are shown in Table 17.

[0108] Table 17

[0109] It can be verified in combination with Table 10 and Table 17 that the aromatic amine with a specific structure in the two-step hydrocyanation reaction method of the present application plays a role in stabilizing the catalyst (nickel content) in the reaction system. In Comparative Example 2, the clear liquid nickel content decreases rapidly (the clear liquid nickel content decreases to 55% of the original amount after 10 hours of reaction), while in Example 5, the clear liquid nickel content remains 96% of the original amount after 10 hours. In addition, the reaction rate of the two-step hydrocyanation in Example 5 is greater than that in Comparative Example 4, which verifies that the aromatic amine A11 has a good effect on improving the reaction rate.

[0110] Comparative Example 3

[0111] A one-step hydrocyanation reaction method, which is carried out in the presence of a nickel-monodentate phosphite ligand catalyst and the aromatic amine A2 to prepare pentenenitrile from butadiene; wherein the monodentate phosphite ligand L11 has the following structure:

[0112] The monodentate phosphite ligand L11 has the substituent structure shown in Table 18:

[0113] Table 18

[0114] The ligand L11 is prepared into a nickel-monodentate phosphite ligand catalyst with nickel powder.

[0115] The raw materials and control parameters of the one-step hydrocyanation reaction method in this comparative example are the same as those in Example 1. As the reaction proceeds, the reaction system is sampled and analyzed at different times, and the results are shown in Table 19.

[0116] Table 19

[0117] It can be verified in combination with Table 3 and Table 19 that the nickel-bidentate phosphite ligand catalyst used in the hydrocyanation reaction method of the present application has higher product selectivity in the process of catalyzing the one-step hydrocyanation reaction method compared to the nickel-monodentate phosphite ligand catalyst used in Comparative Example 3, which reflects the important role of the bidentate phosphite ligand in improving the selectivity of 3PN. In addition, the clear liquid nickel content changes little during the reaction process in Example 1 and Comparative Example 3, which confirms the effect of the aromatic amine A2 in stabilizing the catalyst performance.

[0118] Comparative Example 4

[0119] A two-step hydrocyanation reaction method, which is used to prepare pentenenitrile from butadiene under the action of a nickel-monodentate phosphite ligand catalyst and aromatic amine A11; wherein the nickel-monodentate phosphite ligand catalyst is prepared from ligand L11 and nickel powder.

[0120] In the present comparative example, the raw materials and control parameters of the two-step hydrocyanation reaction method are the same as those in Example 5. During the reaction, the reaction system is sampled and analyzed at different times, and the results are shown in Table 20.

[0121] Table 20

[0122] As can be verified by combining Table 10 and Table 20, the nickel-bidentate phosphite ligand catalyst used in the hydrocyanation reaction method of the present application has higher product selectivity during the catalytic two-step hydrocyanation reaction process than the nickel-monodentate phosphite ligand catalyst used in Comparative Example 4, which reflects that the bidentate phosphite ligand plays an important role in improving the selectivity of 3PN. In addition, the clear liquid Ni content changes little during the reaction in Example 5 and Comparative Example 4, which verifies that the aromatic amine A11 plays a role in stabilizing the catalyst performance during the two-step hydrocyanation process.

[0123] Comparative Example 5

[0124] A two-step hydrocyanation reaction method, which is used to prepare pentenenitrile from butadiene under the action of a nickel-monodentate phosphite ligand catalyst and aromatic amine A11; wherein the nickel-monodentate phosphite ligand catalyst is prepared from ligand L11 and nickel powder.

[0125] Table 21

[0126] As can be verified by combining Table 10 and Table 21, the aromatic amine with a specific structure contained in the hydrocyanation reaction method of the present application plays a role in stabilizing the catalyst (nickel content) in the reaction system, which is specifically manifested as follows: in Comparative Example 5, the clear liquid Ni content decreases rapidly (the clear liquid Ni content is reduced to 75% and 72% of the original amount, respectively, after 10 h of reaction), while in Example 5, the clear liquid Ni content remains 96% of the initial amount after 10 h; this indicates that the aromatic amine with a specific structure contained in the hydrocyanation reaction method of the present application is more conducive to stabilizing the catalyst and reducing catalyst loss; in addition, the reaction rate of the two-step hydrocyanation in Example 5 is greater than that in Comparative Example 5, which verifies that the aromatic amine A11 is superior to the aromatic amine A11-1 containing one aromatic ring and the aromatic amine A11-2 containing three aromatic rings in improving the reaction rate.

[0127] It should be noted that the above is a further detailed description of the present application in combination with specific embodiments, and the specific implementation of the present application cannot be limited to these descriptions; the size data of the embodiments does not limit the technical solutions, but only shows one specific working condition. For ordinary skilled persons in the technical field to which the present application belongs, without departing from the concept of the present application, a number of simple improvements and refinements can be made, which should be considered as belonging to the scope of protection of the present application.

Claims

1. A hydrocyanation process characterized by, The hydrocyanation process is carried out in a reaction system comprising an aromatic amine having the structure: wherein X 1 -X 3 group and Y 1 -Y 3 include any one of hydrogen, alkyl, alkoxy, alkylamine, hydroxyl, and amino.

2. The hydrocyanation process of claim 1 wherein, the alkyl group has the formula -R, the alkoxy group has the formula the alkylamine group has the formula wherein the R group includes any one of a methyl group, an ethyl group, an isopropyl group, and a tert-butyl group.

3. The hydrocyanation process of claim 1 wherein, The structure of the bidentate phosphite ligand is: wherein R 1 -R 4 and Z 1 -Z 5 include any of hydrogen, methyl, ethyl, isopropyl, tert-butyl, methoxy, respectively.

4. The hydrocyanation process of claim 1 wherein, The mass ratio of the nickel-bidentate phosphite ligand catalyst to the aromatic amine is 1:(0.05-0.8), preferably 1:(0.1-0.6).

5. The hydrocyanation process of any of claims 1-4 wherein, The hydrocyanation reaction method is a hydrocyanation reaction method for preparing adiponitrile.

6. The hydrocyanation process of claim 5 wherein, The hydrocyanation reaction method includes a one-step hydrocyanation reaction method for preparing pentenenitrile by taking butadiene as a raw material. Preferably, the reaction temperature of the one-step hydrocyanation reaction method is 40-110°C, preferably 50-95°C.

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

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

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

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

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