Method for preparing hexamethylenediamine based on cyclohexene

Abstract

The application discloses a method for preparing hexamethylenediamine based on cyclohexene. The preparation method comprises: respectively injecting the mixed liquid and the mixed gas containing ozone into a microchannel reactor, and performing an oxidation reaction under reaction conditions to obtain Adipaldehyde, wherein, the mixed solution contains cyclohexene and a metal compound catalyst; the raw material containing the adipaldehyde is reacted to generate hexamethylenediamine in the presence of ammonia, hydrogen and Ni-based catalyst; wherein, The Ni-based catalyst consists of Ni-containing 2+ produced from hydrotalcite. Using cyclohexene as raw material, hexamethylenediamine is prepared by oxidation and amination, avoiding the use of highly toxic raw material adiponitrile, using ozone as oxidant, heterogeneous catalyst can produce adipaldehyde with high selectivity, and further using Ni-based catalyst , catalyzing the reductive amination of adipaldehyde to prepare hexamethylenediamine, avoiding the use of highly toxic raw material adiponitrile, and the route is clean and environmentally friendly.

Description

technical field

[0001] The application relates to a method for preparing hexamethylenediamine based on cyclohexene, which belongs to the field of chemical engineering. Background technique

[0002] Hexamethylenediamine is an important organic chemical raw material, which can be polycondensed with adipic acid to produce polyhexamethylene adipamide, also known as polyamide 66 (PA66) or nylon 66. Nylon 66 can be used for injection molding, extrusion, blow molding, spraying, casting, machining, welding, and bonding. About 90% of hexamethylenediamine produced in the world is used in the production of nylon 66. The production technologies of hexamethylenediamine mainly include adiponitrile method, hexanediol method and caprolactam method. At present, almost all hexamethylenediamine is prepared by hydrogenation of adiponitrile, and the production methods of adiponitrile include catalytic amination of adipic acid, electrolytic dimerization of acrylonitrile and butadiene method. ...

Examples

Embodiment 1

[0074] Cyclohexene oxidation is adipaldehyde in embodiment 1' microchannel reactor

[0075] 50 g of cyclohexene and 116 g of acetone were mixed to prepare a cyclohexene solution with a mass concentration of 30%, and 7.89 g of vanadyl acetylacetonate was added to the cyclohexene solution, and the mixed solution was obtained after ultrasonic vibration and uniform mixing;

[0076] A pump is used to inject the mixed solution into the microchannel reactor, and the flow rate of the mixed solution is 10g / min. At the same time, the mixed gas is injected into the microchannel reactor through a mass flow meter, and the flow rate of the mixed gas is controlled to be 15.1L / min. Composed of ozone, the ozone concentration is 100mg / L;

[0077] The reaction temperature in the microchannel reactor was 10° C., the reaction pressure was 0.10 MPa, and the materials were collected after 10 minutes of reaction, and analyzed by gas chromatography.

Embodiment 2

[0078] Cyclohexene is oxidized to adipaldehyde in embodiment 2'-11' microchannel reactor

[0079] Adopt the described operation of embodiment 1 ', change the pressure of reaction, solvent, catalyzer and temperature of reaction to react, concrete reaction condition and result are shown in Table 1.

[0080] Table 1 Reaction conditions and result list of cyclohexene oxidation to adipaldehyde in microchannel reactor

[0081]

[0082]

[0083] As can be seen from Table 1, in the preparation process provided by the application, adipaldehyde generally has higher selectivity, and the selectivity of adipaldehyde can reach more than 53.8%, the highest can reach 91.2%, and the conversion rate of cyclohexene can reach 35.2% above, up to 100%.

[0084] Preparation of Ni-based catalyst: The ratios of ions in the following examples are all molar ratios unless otherwise specified.

[0085] Embodiment 1 prepares NiMgAl-01 catalyst with hydrotalcite as precursor, (Ni 2+ +Mg 2+ ):Al 3...

Embodiment 3

[0089] Embodiment 3 prepares NiMgAl-03 catalyst with hydrotalcite as precursor, (Ni 2+ +Mg 2+ ):Al 3+ The ratio is 3:1, Ni 2+ : Mg 2+ The ratio is 3.0

[0090] 78.52gNi(NO 3 ) 2 ·6H 2 O, 46.89gAl(NO 3 ) 3 9H 2 O and 23.07gMg(NO 3 ) 2 ·6H 2 O is completely dissolved in 500ml of water to obtain mixed solution I; weigh 26.5gNa 2 CO 3 and 70g of NaOH were completely dissolved in 1L of water to obtain the mixed solution II; the two mixed solutions were slowly added dropwise to 200mL of water at the same time, vigorously stirred at a speed of 600r / min, and the pH was maintained at 10. After the addition was completed, the obtained colloidal suspension Transfer to an oven, age at 65°C for 72h, wash with distilled water until neutral, and dry to obtain Ni-based hydrotalcite, and further roast the obtained Ni-based hydrotalcite precursor at 500°C for 4h to obtain highly dispersed Ni base catalyst.

technical field

[0001] The application relates to a method for preparing hexamethylenediamine based on cyclohexene, which belongs to the field of chemical engineering. Background technique

[0002] Hexamethylenediamine is an important organic chemical raw material, which can be polycondensed with adipic acid to produce polyhexamethylene adipamide, also known as polyamide 66 (PA66) or nylon 66. Nylon 66 can be used for injection molding, extrusion, blow molding, spraying, casting, machining, welding, and bonding. About 90% of hexamethylenediamine produced in the world is used in the production of nylon 66. The production technologies of hexamethylenediamine mainly include adiponitrile method, hexanediol method and caprolactam method. At present, almost all hexamethylenediamine is prepared by hydrogenation of adiponitrile, and the production methods of adiponitrile include catalytic amination of adipic acid, electrolytic dimerization of acrylonitrile and butadiene method. ...

Examples

Embodiment 1

[0074] Cyclohexene oxidation is adipaldehyde in embodiment 1' microchannel reactor

[0075] 50 g of cyclohexene and 116 g of acetone were mixed to prepare a cyclohexene solution with a mass concentration of 30%, and 7.89 g of vanadyl acetylacetonate was added to the cyclohexene solution, and the mixed solution was obtained after ultrasonic vibration and uniform mixing;

[0076] A pump is used to inject the mixed solution into the microchannel reactor, and the flow rate of the mixed solution is 10g / min. At the same time, the mixed gas is injected into the microchannel reactor through a mass flow meter, and the flow rate of the mixed gas is controlled to be 15.1L / min. Composed of ozone, the ozone concentration is 100mg / L;

[0077] The reaction temperature in the microchannel reactor was 10° C., the reaction pressure was 0.10 MPa, and the materials were collected after 10 minutes of reaction, and analyzed by gas chromatography.

Embodiment 2

[0078] Cyclohexene is oxidized to adipaldehyde in embodiment 2'-11' microchannel reactor

[0079] Adopt the described operation of embodiment 1 ', change the pressure of reaction, solvent, catalyzer and temperature of reaction to react, concrete reaction condition and result are shown in Table 1.

[0080] Table 1 Reaction conditions and result list of cyclohexene oxidation to adipaldehyde in microchannel reactor

[0081]

[0082]

[0083] As can be seen from Table 1, in the preparation process provided by the application, adipaldehyde generally has higher selectivity, and the selectivity of adipaldehyde can reach more than 53.8%, the highest can reach 91.2%, and the conversion rate of cyclohexene can reach 35.2% above, up to 100%.

[0084] Preparation of Ni-based catalyst: The ratios of ions in the following examples are all molar ratios unless otherwise specified.

[0085] Embodiment 1 prepares NiMgAl-01 catalyst with hydrotalcite as precursor, (Ni 2+ +Mg 2+ ):Al 3...

Embodiment 3

[0089] Embodiment 3 prepares NiMgAl-03 catalyst with hydrotalcite as precursor, (Ni 2+ +Mg 2+ ):Al 3+ The ratio is 3:1, Ni 2+ : Mg 2+ The ratio is 3.0

[0090] 78.52gNi(NO 3 ) 2 ·6H 2 O, 46.89gAl(NO 3 ) 3 9H 2 O and 23.07gMg(NO 3 ) 2 ·6H 2 O is completely dissolved in 500ml of water to obtain mixed solution I; weigh 26.5gNa 2 CO 3 and 70g of NaOH were completely dissolved in 1L of water to obtain the mixed solution II; the two mixed solutions were slowly added dropwise to 200mL of water at the same time, vigorously stirred at a speed of 600r / min, and the pH was maintained at 10. After the addition was completed, the obtained colloidal suspension Transfer to an oven, age at 65°C for 72h, wash with distilled water until neutral, and dry to obtain Ni-based hydrotalcite, and further roast the obtained Ni-based hydrotalcite precursor at 500°C for 4h to obtain highly dispersed Ni base catalyst.

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