Process for continuously preparing 1,2-cyclohexanediamine from cyclohexene oxide

Abstract

The present invention belongs to the field of fine chemical engineering and provides a synthetic process for continuously preparing 1,2-cyclohexanediamine from cyclohexene oxide. The raw material cyclohexene oxide and ammonia water are passed through a No. 1 reactor equipped with a solid acid catalyst in a certain proportion, and a hydrolysis reaction is carried out under certain reaction process conditions; the mixed liquid obtained from the reaction enters a static mixer and is mixed with hydrogen in a certain proportion, and after being uniformly mixed, it enters a No. 2 reactor equipped with a nickel-based catalyst, and a hydroamination reaction is carried out under certain reaction process conditions; finally, the product enters a gas-liquid separator, and 1,2-cyclohexanediamine is separated. The present invention innovatively realizes the one-step reaction of cyclohexene oxide to obtain 1,2-cyclohexanediamine by connecting the hydrolysis reactor and the hydroamination reactor in series.

Description

Technical Field

[0001] The present invention belongs to the field of catalytic ammoniation, and relates to a synthetic process for continuously preparing 1,2-cyclohexanediamine from cyclohexene oxide. Background Art

[0002] Cyclohexanediamine is an important organic chemical, which can be used as a raw material for dyes and pharmaceutical intermediates, and is also an important intermediate for polyurethanes. 1,2-Cyclohexanediamine has a C2 symmetry axis and is a chiral compound with great research prospects. It can be used to synthesize various chiral ligands or chiral catalysts and has a wide range of applications in the fields of asymmetric catalysis, molecular recognition, and medicine.

[0003] Currently, the 1,2-cyclohexanediamine on the market mainly comes from the by-products generated during the production of hexamethylenediamine by hydrogenation of adiponitrile. The production process route of adiponitrile is complex and requires the use of highly toxic chemical raw materials. Therefore, this production process is only mastered by a few multinational companies, resulting in limited supply of adiponitrile, indirectly leading to insufficient supply of 1,2-cyclohexanediamine, high costs, and restricting the downstream applications of 1,2-cyclohexanediamine.

[0004] Cyclohexene oxide mainly comes from the light oil by-products during the oxidation of cyclohexane. There are many domestic cyclohexane oxidation synthesis of cyclohexanone devices with large production capacity and sufficient supply of the process raw material cyclohexene oxide. Therefore, developing the synthesis of 1,2-cyclohexanediamine from cyclohexene oxide has good application prospects. Summary of the Invention

[0005] The purpose of the present invention is to provide a process for continuously preparing 1,2-cyclohexanediamine from cyclohexene oxide.

[0006] The synthesis of continuously preparing 1,2-cyclohexanediamine from cyclohexene oxide described in the present invention is characterized in that the reaction process includes the following steps: (1) The raw material cyclohexene oxide and ammonia water are passed through a No. 1 reactor equipped with a solid acid catalyst in a certain ratio, and a hydrolysis reaction is carried out under certain reaction process conditions; (2) The mixed liquid obtained from the reaction in step (1) and hydrogen are mixed in a static mixer in a certain ratio, and after being mixed evenly, they enter a No. 2 reactor equipped with a nickel-based catalyst, and a hydroamination reaction is carried out under certain reaction process conditions; (3) Finally, the product enters a gas-liquid separator, and 1,2-cyclohexanediamine is separated.

[0007] Furthermore, the ratio of cyclohexene oxide to ammonia water in the present invention is 1:15 to 1:30 (mass ratio).

[0008] The concentration of the ammonia water described in the present invention is 25% to 28%.

[0009] The No. 1 reactor described in the present invention is bottom-in and top-out, and the height-diameter ratio of the reactor is 1:12 to 1:20.

[0010] The solid acid catalyst described in the present invention is one of acidic zeolite molecular sieves, heteropolyacids, cation exchange resins, and solid superacid catalysts.

[0011] The hydrolysis reaction process conditions in the present invention are as follows: the reaction temperature is 80 - 150 °C, and the volume space velocity is 0.1 - 1.5 h -1 , and the reaction pressure is 3 - 9 MPa.

[0012] The molar ratio of hydrogen to cyclohexene oxide in the present invention is 1:2 - 1:10.

[0013] The No. 2 reactor described in the present invention has an up - inlet and down - outlet structure, and the height - to - diameter ratio of the reactor is 1:9 - 1:15.

[0014] The nickel - based catalyst described in the present invention is Ni / Al2O3, with the metal Ni content being 15 - 25% wt and the Al2O3 content being 65 - 85% wt.

[0015] The hydroamination process conditions in the present invention are as follows: the reaction temperature is 210 - 280 °C, and the volume space velocity is 0.1 - 1.5 h -1 , and the reaction pressure is 3 - 9 MPa.

[0016] The present invention innovatively connects the hydrolysis reactor and the hydroamination reactor in series to realize the one - step reaction of cyclohexene oxide to obtain 1,2 - cyclohexanediamine, which has good application prospects. Brief Description of the Drawings

[0017] Figure 1 It is a schematic process flow diagram for continuously preparing 1,2 - cyclohexanediamine from cyclohexene oxide in an embodiment of the present invention.

[0018] Detailed Description of Specific Embodiments

[0019] The process of the present invention will be described in detail below in combination with examples and drawings.

[0020] In the following examples, the process flow for continuously preparing 1,2 - cyclohexanediamine from cyclohexene oxide refers to the attached Figure 1 .

[0021] Example 1

[0022] The raw material cyclohexene oxide and ammonia water are injected into Reactor 1 (height-to-diameter ratio 1:15) at a ratio of 1:20 (ammonia water concentration 20% by mass). 60 mL of solid acid catalyst HND-32 (Nanda Synthetic Chemistry Co., Ltd.) is loaded in Reactor 1. The hydrolysis process conditions are shown in Table 1. Hydrogen is pressurized by a hydrogen booster and then injected into a static mixer. The molar ratio of hydrogen to cyclohexene oxide is 1:4. After being uniformly mixed with the mixed solution in Reactor 1, it is injected into Reactor 2 (height-to-diameter ratio 1:12). 60 mL of 3 mm×3 mm nickel-based catalyst (self-made by Sinopec Nanjing Research Institute of Chemical Industry Co., Ltd.) is loaded in Reactor 2. The Ni content of the catalyst is 18.5% wt and the Al2O3 content is 81.5% wt. The hydroamination process conditions are shown in Table 1. Finally, the product enters a gas-liquid separator to obtain 1,2-cyclohexanediamine.

[0023] Table 1 Reaction conditions and reaction results of Example 1

[0024]

[0025] Note: X , conversion rate of cyclohexene oxide; S， selectivity of 1,2-cyclohexanediamine.

[0026] Example 2

[0027] The raw material cyclohexene oxide and ammonia water are injected into Reactor 1 (height-to-diameter ratio 1:14) at a ratio of 1:25 (ammonia water concentration 20% by mass). 60 mL of solid acid catalyst HND-8 (Nanda Synthetic Chemistry Co., Ltd.) is loaded in Reactor 1. The hydrolysis process conditions are shown in Table 1. Hydrogen is pressurized by a hydrogen booster and then injected into a static mixer. The molar ratio of hydrogen to cyclohexene oxide is 1:6. After being uniformly mixed with the mixed solution in Reactor 1, it is injected into Reactor 2 (height-to-diameter ratio 1:15). 60 mL of 3 mm×3 mm nickel-based catalyst (self-made by Sinopec Nanjing Research Institute of Chemical Industry Co., Ltd.) is loaded in Reactor 2. The Ni content of the catalyst is 24% wt and the Al2O3 content is 76% wt. The hydroamination process conditions are shown in Table 2. Finally, the product enters a gas-liquid separator to obtain 1,2-cyclohexanediamine.

[0028] Table 2 Reaction conditions and reaction results of Example 2

[0029]

[0030] Note: X , conversion rate of cyclohexene oxide; S， selectivity of 1,2-cyclohexanediamine.

[0031] Example 3:

[0032] The raw material cyclohexene oxide and ammonia water are injected into Reactor 1 (height-to-diameter ratio 1:12) at a ratio of 1:15 (ammonia water concentration 25% by mass). 60 mL of solid acid catalyst HND-2 (produced by Nanda Synthetic Chemistry Co., Ltd.) is installed in Reactor 1. The hydrolysis process conditions are shown in Table 1. Hydrogen is pressurized by a hydrogen booster and then injected into a static mixer. The molar ratio of hydrogen to cyclohexene oxide is 1:8. After being evenly mixed with the mixed solution in Reactor 1, it is injected into Reactor 2 (height-to-diameter ratio 1:15). 60 mL of a 3 mm × 3 mm nickel-based catalyst (self-made by Sinopec Nanjing Research Institute of Chemical Industry Co., Ltd.) is installed in Reactor 2. The catalyst contains 28.6% wt of Ni and 71.4% wt of Al2O3. The hydroamination process conditions are shown in Table 3. Finally, the product enters a gas-liquid separator, and 1,2-cyclohexanediamine is separated out.

[0033] Table 3 Reaction Conditions and Reaction Results of Example 3

[0034]

[0035] Note: X , conversion rate of cyclohexene oxide; S， selectivity of 1,2-cyclohexanediamine.

[0036] Example 4:

[0037] The raw material cyclohexene oxide and ammonia water are injected into Reactor 1 (height-to-diameter ratio 1:12) at a ratio of 1:30 (ammonia water concentration 25% by mass). 60 mL of solid acid catalyst HND-8 (produced by Nanda Synthetic Chemistry Co., Ltd.) is installed in Reactor 1. The hydrolysis process conditions are shown in Table 1. Hydrogen is pressurized by a hydrogen booster and then injected into a static mixer. The molar ratio of hydrogen to cyclohexene oxide is 1:6. After being evenly mixed with the mixed solution in Reactor 1, it is injected into Reactor 2 (height-to-diameter ratio 1:15). 60 mL of a 3 mm × 3 mm nickel-based catalyst (self-made by Sinopec Nanjing Research Institute of Chemical Industry Co., Ltd.) is installed in Reactor 2. The catalyst contains 29.1% wt of Ni and 70.6% wt of Al2O3. The hydroamination process conditions are shown in Table 4. Finally, the product enters a gas-liquid separator, and 1,2-cyclohexanediamine is separated out.

[0038] Table 4 Reaction Conditions and Reaction Results of Example 4

[0039]

[0040] Note: X , conversion rate of cyclohexene oxide; S， selectivity of 1,2-cyclohexanediamine.

[0041] Example 5:

[0042] The raw material cyclohexene oxide and ammonia water are injected into the No. 1 reactor (height-diameter ratio 1:15) at a ratio of 1:25 (ammonia water concentration 25% by mass). 60 mL of solid acid catalyst HND-2 (Nanda Synthetic Chemistry Co., Ltd.) is installed in the No. 1 reactor. The hydrolysis process conditions are shown in Table 1; hydrogen is pressurized by a hydrogen booster and then injected into a static mixer. The molar ratio of hydrogen to cyclohexene oxide is 1:6. After being mixed evenly with the mixed solution in Reactor 1, it is injected into the No. 2 reactor (height-diameter ratio 1:15). 60 mL of 3 mm×3 mm nickel-based catalyst (self-made by Sinopec Nanjing Research Institute of Chemical Industry Co., Ltd.) is installed in the No. 2 reactor. The Ni content of the catalyst is 24.25% wt, and the Al2O3 content is 75.75% wt. The hydroamination process conditions are shown in Table 5. Finally, the product enters a gas-liquid separator to obtain 1,2-cyclohexanediamine.

[0043] Table 5 Reaction Conditions and Reaction Results of Example 5

[0044]

[0045] Note: X , conversion rate of cyclohexene oxide; S， selectivity of 1,2-cyclohexanediamine.

[0046] Example 6:

[0047] The raw material cyclohexene oxide and ammonia water are injected into the No. 1 reactor (height-diameter ratio 1:14) at a ratio of 1:20 (ammonia water concentration 25% by mass). 60 mL of solid acid catalyst HND-583 (Nanda Synthetic Chemistry Co., Ltd.) is installed in the No. 1 reactor. The hydrolysis process conditions are shown in Table 1; hydrogen is pressurized by a hydrogen booster and then injected into a static mixer. The molar ratio of hydrogen to cyclohexene oxide is 1:6. After being mixed evenly with the mixed solution in Reactor 1, it is injected into the No. 2 reactor (height-diameter ratio 1:14). 60 mL of 3 mm×3 mm nickel-based catalyst (self-made by Sinopec Nanjing Research Institute of Chemical Industry Co., Ltd.) is installed in the No. 2 reactor. The Ni content of the catalyst is 26.35% wt, and the Al2O3 content is 73.65% wt. The hydroamination process conditions are shown in Table 6. Finally, the product enters a gas-liquid separator to obtain 1,2-cyclohexanediamine.

[0048] Table 6 Reaction Conditions and Reaction Results of Example 6

[0049]

[0050] Note: X , conversion rate of cyclohexene oxide; S， selectivity of 1,2-cyclohexanediamine.

[0051] Example 7:

[0052] The raw material cyclohexene oxide and ammonia water are injected into Reactor 1 (height-to-diameter ratio 1:15) at a mass ratio of 1:15 (ammonia water concentration 25% by mass). 60 mL of solid acid catalyst HND-8 (produced by Nanda Synthetic Chemistry Co., Ltd.) is installed in Reactor 1. The hydrolysis process conditions are shown in Table 1. Hydrogen is pressurized by a hydrogen booster and then injected into a static mixer. The molar ratio of hydrogen to cyclohexene oxide is 1:9. After being evenly mixed with the mixed solution in Reactor 1, it is injected into Reactor 2 (height-to-diameter ratio 1:15). 60 mL of a 3 mm × 3 mm nickel-based catalyst (self-made by Sinopec Nanjing Research Institute of Chemical Industry Co., Ltd.) is installed in Reactor 2. The Ni content of the catalyst is 29.1% wt, and the Al2O3 content is 70.6% wt. The process conditions for hydroamination are shown in Table 7. Finally, the product enters a gas-liquid separator, and 1,2-cyclohexanediamine is separated out.

[0053] Table 7 Reaction Conditions and Reaction Results of Example 7

[0054]

[0055] Note: X , conversion rate of cyclohexene oxide; S， selectivity of 1,2-cyclohexanediamine.

Claims

1. A process for continuously preparing 1,2-cyclohexanediamine from cyclohexene oxide, characterized in that, The continuous preparation process includes the following steps: (1) passing raw material cyclohexene oxide and ammonia water in a mass ratio of 1:15 to 1:30 through a No. 1 reactor equipped with a solid acid catalyst for hydrolysis reaction, with the hydrolysis reaction temperature being 80 to 150 °C and the volumetric space velocity being 0.1 to 1.5 h -1 , and the reaction pressure being 3 to 9 MPa; the concentration of the ammonia water being 25 to 28%; (2) the mixed liquid obtained from the reaction in step (1) and hydrogen enter a static mixer in proportion for mixing, and after being uniformly mixed, enter a No. 2 reactor equipped with a nickel-based catalyst for hydroamination reaction; (3) finally, the product enters a gas-liquid separator to separate 1,2-cyclohexanediamine.

2. The process according to claim 1, characterized in that The No. 1 reactor has a downward inlet and an upward outlet, and the height-diameter ratio of the reactor is 1:12 to 1:

20.

3. The process according to claim 1, characterized in that The solid acid catalyst is one of acidic zeolite molecular sieves, heteropolyacids, cation exchange resins, and solid superacid catalysts.

4. The process according to claim 1, characterized in that The molar ratio of hydrogen to cyclohexene oxide is 1:2 to 1:

10.

5. The process according to claim 1, characterized in that The No. 2 reactor has an upward inlet and a downward outlet, and the height-diameter ratio of the reactor is 1:9 to 1:

15.

6. The process according to claim 1, characterized in that The nickel-based catalyst is Ni / Al2O3, with the metal Ni content of 15 - 25%wt and the Al2O3 content of 65 - 85%wt.

7. The process according to claim 1, characterized in that Process conditions for hydroamination: reaction temperature is 210~280°C, volumetric space velocity is 0.1~1.5 h -1 , and reaction pressure is 3~9 MPa.

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