Refining method of adiponitrile

Abstract

The invention provides a refining method of adiponitrile, which is characterized in that ICCP in crude adiponitrile is hydrolyzed and converted into 2-cyanocyclopentanone, and then the 2-cyanocyclopentanone is rectified and removed to obtain high-purity adiponitrile. The principle of the invention is as follows: under the pressure of 2.0 KPa, the boiling point of 2-cyanocyclopentanone is 137-140 DEG C, the boiling point of ICCP is 152-154 DEG C, and the boiling point of adiponitrile is 168 DEG C, so that the 2-cyanocyclopentanone is separated from the adiponitrile more easily than the ICCP in the subsequent rectification separation process, and the amount of the adiponitrile taken out when the 2-cyanocyclopentanone is distilled out from the tower top is much lower than the amount of the adiponitrile taken out when the ICCP is separated. Therefore, the refining method of the adiponitrile provided by the invention is simple; The ICCP in the crude adiponitrile is converted into the 2-cyanocyclopentanone, so that the removal effect of the ICCP is good, the refining yield of the adiponitrile is higher, and the purity of the refined adiponitrile product is also high. The method can better meet the quality requirements of downstream products on adiponitrile; specifically, the content of adiponitrile in the obtained product is 99.9% or above, and the content of ICCP is less than 50 ppm.

Description

technical field

[0001] The invention belongs to the technical field of refining or purifying chemical products, and in particular relates to a method for refining adiponitrile. Background technique

[0002] Adiponitrile (ADN) alias 1,4-diaminobutane, the molecular formula is NC (CH 3 ) 4 CN is a colorless oily liquid with a slight odor and stable properties. It is mainly used in the production of polyamide fiber intermediate hexamethylenediamine, rubber accelerator and antirust agent. The addition of adiponitrile and hydrogen can produce hexamethylenediamine, and the reaction of hexamethylenediamine and adipic acid under strict material ratio produces nylon 66 salt. As an important intermediate for the synthesis of nylon 66, adiponitrile is the most important and most valuable industrial use developed by adiponitrile. Hexamethylenediamine can also synthesize 1,6-hexamethylene diisocyanate (HDI), which is another important use for the development of the downstream product...

Examples

Embodiment 1

[0072] The present embodiment provides a kind of refining device of adiponitrile, such as figure 1 shown, including:

[0073] The extract liquid mixer 1 includes a crude adiponitrile inlet, an extract liquid inlet, and an organic mixed liquid outlet. The outlet of the organic mixed liquid is communicated with the inlet of the organic mixed liquid of the ICCP hydrolysis reactor 9.

[0074] The dilute acid mixer 8 includes a desalted water inlet, a concentrated acid solution inlet, and a dilute acid aqueous solution outlet. The outlet of the dilute acid aqueous solution communicates with the inlet of the dilute acid aqueous solution of the ICCP hydrolysis reactor 9.

[0075] The ICCP hydrolysis reactor 9 comprises a stirring mixer, an aldehyde aqueous solution inlet, a dilute acid aqueous solution inlet, an organic mixed solution inlet, and a hydrolysis reaction liquid outlet; The organic mixed solution is evenly mixed to promote the rapid hydrolysis of ICCP to generate 2-cya...

Embodiment 2

[0115] The present embodiment provides a kind of refining method of adiponitrile, adopts figure 1 Shown adiponitrile refining system specifically comprises the steps:

[0116] The crude adiponitrile in this embodiment is the crude adiponitrile solution obtained after the reaction mixture obtained by the reaction of adipic acid and ammonia is separated and washed with ammonia water, and its composition is: adiponitrile 88.48% (wt), ICCP0.41 %(wt), 5-cyanovaleramide 1.60% (wt), 5-cyanovaleric acid 0.06wt%, adipamide 0.12wt%, ammonia 0.45wt%, water 8.59wt%, cyclopentanone 0.29 % (wt).

[0117] (1) Hydrolysis and washing separation of ICCP

[0118] The thick adiponitrile solution of 100kg / h and the toluene extraction solution 103.66kg / h sent through the extract storage tank 2 are mixed uniformly in the extract mixer 1 and then enter the ICCP hydrolysis reactor 9, and react in the ICCP hydrolysis reaction Add 5.0kg / h of 35% formaldehyde solution into vessel 9, then add 13.10kg / h...

Embodiment 3

[0135] The present embodiment provides a kind of refining method of adiponitrile, adopts figure 1 Shown adiponitrile refining system specifically comprises the steps:

[0136] The crude adiponitrile in this embodiment is the crude adiponitrile solution obtained after the reaction mixture obtained by the reaction of adipic acid and ammonia after separation and washing with ammonia water, and its composition is: adiponitrile 89.68% (wt), ICCP0.42 % (wt), 5-cyanovaleramide 1.39% (wt), 5-cyanovaleric acid 0.09% (wt), adipamide 0.09% (wt), ammonia 0.36% (wt), water 7.75% (wt), cyclopentanone 0.22% (wt).

[0137] (1) Hydrolysis and washing separation of ICCP

[0138] The thick adiponitrile solution of 100kg / h and the toluene extraction solution 153.29kg / h sent through the extract storage tank 2 are mixed uniformly in the extract mixer 1 and enter the ICCP hydrolysis reactor 9, and in the conversion reactor 9 Add 35% formaldehyde solution 2.0kg / h to the solution, then add 10% (wt)...

technical field

[0001] The invention belongs to the technical field of refining or purifying chemical products, and in particular relates to a method for refining adiponitrile. Background technique

[0002] Adiponitrile (ADN) alias 1,4-diaminobutane, the molecular formula is NC (CH 3 ) 4 CN is a colorless oily liquid with a slight odor and stable properties. It is mainly used in the production of polyamide fiber intermediate hexamethylenediamine, rubber accelerator and antirust agent. The addition of adiponitrile and hydrogen can produce hexamethylenediamine, and the reaction of hexamethylenediamine and adipic acid under strict material ratio produces nylon 66 salt. As an important intermediate for the synthesis of nylon 66, adiponitrile is the most important and most valuable industrial use developed by adiponitrile. Hexamethylenediamine can also synthesize 1,6-hexamethylene diisocyanate (HDI), which is another important use for the development of the downstream product...

Examples

Embodiment 1

[0072] The present embodiment provides a kind of refining device of adiponitrile, such as figure 1 shown, including:

[0073] The extract liquid mixer 1 includes a crude adiponitrile inlet, an extract liquid inlet, and an organic mixed liquid outlet. The outlet of the organic mixed liquid is communicated with the inlet of the organic mixed liquid of the ICCP hydrolysis reactor 9.

[0074] The dilute acid mixer 8 includes a desalted water inlet, a concentrated acid solution inlet, and a dilute acid aqueous solution outlet. The outlet of the dilute acid aqueous solution communicates with the inlet of the dilute acid aqueous solution of the ICCP hydrolysis reactor 9.

[0075] The ICCP hydrolysis reactor 9 comprises a stirring mixer, an aldehyde aqueous solution inlet, a dilute acid aqueous solution inlet, an organic mixed solution inlet, and a hydrolysis reaction liquid outlet; The organic mixed solution is evenly mixed to promote the rapid hydrolysis of ICCP to generate 2-cya...

Embodiment 2

[0115] The present embodiment provides a kind of refining method of adiponitrile, adopts figure 1 Shown adiponitrile refining system specifically comprises the steps:

[0116] The crude adiponitrile in this embodiment is the crude adiponitrile solution obtained after the reaction mixture obtained by the reaction of adipic acid and ammonia is separated and washed with ammonia water, and its composition is: adiponitrile 88.48% (wt), ICCP0.41 %(wt), 5-cyanovaleramide 1.60% (wt), 5-cyanovaleric acid 0.06wt%, adipamide 0.12wt%, ammonia 0.45wt%, water 8.59wt%, cyclopentanone 0.29 % (wt).

[0117] (1) Hydrolysis and washing separation of ICCP

[0118] The thick adiponitrile solution of 100kg / h and the toluene extraction solution 103.66kg / h sent through the extract storage tank 2 are mixed uniformly in the extract mixer 1 and then enter the ICCP hydrolysis reactor 9, and react in the ICCP hydrolysis reaction Add 5.0kg / h of 35% formaldehyde solution into vessel 9, then add 13.10kg / h...

Embodiment 3

[0135] The present embodiment provides a kind of refining method of adiponitrile, adopts figure 1 Shown adiponitrile refining system specifically comprises the steps:

[0136] The crude adiponitrile in this embodiment is the crude adiponitrile solution obtained after the reaction mixture obtained by the reaction of adipic acid and ammonia after separation and washing with ammonia water, and its composition is: adiponitrile 89.68% (wt), ICCP0.42 % (wt), 5-cyanovaleramide 1.39% (wt), 5-cyanovaleric acid 0.09% (wt), adipamide 0.09% (wt), ammonia 0.36% (wt), water 7.75% (wt), cyclopentanone 0.22% (wt).

[0137] (1) Hydrolysis and washing separation of ICCP

[0138] The thick adiponitrile solution of 100kg / h and the toluene extraction solution 153.29kg / h sent through the extract storage tank 2 are mixed uniformly in the extract mixer 1 and enter the ICCP hydrolysis reactor 9, and in the conversion reactor 9 Add 35% formaldehyde solution 2.0kg / h to the solution, then add 10% (wt)...

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