Method for synthesizing paraphthaloyl chloride through continuous flow in microchannel reactor

Abstract

The disclosure provides a method for synthesizing paraphthaloyl chloride through terephthalic acid chlorination in a reaction mode of a microchannel continuous flow. Compared with an existing technology, this method has characteristics of accurate control of reaction conditions, high phosgene/triphosgene utilization ratio, low catalyst dosage, high TPA conversion ratio within few tens of seconds of reaction time, high TPC yield and the like.

Claims

1. (canceled)

2. (canceled)

3. (canceled)

4. (canceled)

5. (canceled)

6. (canceled)

7. (canceled)

8. (canceled)

9. (canceled)

10. (canceled)

11. A method for preparing paraphthaloyl chloride through terephthalic acid chlorination in a microchannel reactor, wherein the method comprises the following steps: (1) a preparation of raw materials: a. firstly melting a paraphthaloyl chloride, and then putting a terephthalic acid and a catalyst into the paraphthaloyl chloride, stirring and mixing to obtain a TPA slurry; and b. melting a solid triphosgene to obtain a triphosgene liquid; or, preparing phosgene; (2) reaction process: in a reaction process, using a continuous flow microchannel reactor, using the TPA slurry as a first flow of a material, and using the triphosgene liquid or the phosgene as a second flow of a material; and respectively feeding the first flow of the material and the second flow of the material into the microchannel reactor for performing a mixing reaction, to obtain a TPC crude product, absorbing a tail gas by connecting water and alkali.

12. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 11, wherein the catalyst is one or more in a group formed by N,N-dimethylformamide, pyridine and N,N-dimethylacetamide, and a dosage of the catalyst is 0.1% -3% of a mass of the TPA.

13. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 12, wherein the catalyst is the N,N-dimethylformamide, and the dosage of the catalyst is 0.5%-3% of the mass of the TPA.

14. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 11, wherein in a preparation process of the raw materials, a mass ratio of the TPA and the TPC is 1:1-1:10.

15. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 14, wherein in slurry preparation, a mass ratio of the terephthalic acid and the paraphthaloyl chloride is 1:1-1:5,

16. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 11, wherein while the phosgene is used as the raw material, a mole ratio of the phosgene and TPA is 2.0-2.8:1; and while the solid triphosgene is used as the raw material, a mole ratio of the solid triphosgene and the TPA is 2.0-2.8:1.

17. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 11, wherein in a reaction process, a reaction temperature is 100-140 DEG C.

18. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 17, wherein in the reaction process, the reaction temperature is 100-120 DEG C.

19. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 11, wherein in the reaction process, a reaction standing time is 10-300 s.

20. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 19, wherein in the reaction process, the reaction standing time is 30-120 s.

21. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 11, wherein in the reaction process, the TPA slurry is fed through a heat-preserving slurry pump, the phosgene is fed through a mass flowmeter, and the triphosgene liquid is fed by a heat-preserving plunger pump.

22. The method for preparing the paraphthaloyl chloride through the terephthalic acid chlorination in the microchannel reactor as claimed in claim 11, wherein in the preparation of the raw materials, melting the paraphthaloyl chloride, and then putting the terephthalic acid and the catalyst into the paraphthaloyl chloride, stirring and mixing to form uniform slurry, and heat-preserving in the oil bath of 90 DEG C, to obtain the TPA slurry; stirring, melting, and heat-preserving the solid triphosgene in the oil bath of 85 DEG C, to obtain the triphosgene liquid.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Drawings of description forming one part of the application are used for providing further understanding to the disclosure, schematic embodiments of the disclosure and description thereof are used for explaining the disclosure, and are not intended to improperly limit the disclosure. In the drawings:

[0049] FIG. 1 shows a phosgene method technology block diagram of the disclosure; and

[0050] FIG. 2 shows a triphosgene method technology block diagram of the disclosure.

DETAILED DESCRIPTION OF THE EMBODIMENTS

[0051] It is to be noted that the embodiments in the application and features in the embodiments can be mutually combined in the case without conflicting. The disclosure is described in detail below with reference to the drawings and in combination with the embodiments.

[0052] The application is further described in detail below in combination with the specific embodiments, these embodiments may not be understood to limit a scope of protection required by the disclosure.

Embodiment 1

[0053] 1. Preparation of raw materials: 2000 g of TPC is weighed, and put into a 2000 ml four-opening flask. The four-opening flask is placed in an oil bath of 90 DEG C for heating and melting, and 500 g of TPA (sieving in 200 meshes in advance) and 10 g of DMF are added, uniform slurry is formed by stirring and mixing for future use. A phosgene is fed into a microreactor for future use by a pipeline through a mass flowmeter, a one-way valve, a safety valve and the like.

[0054] 2. In a heart-shaped microchannel, of which a material is special glass, a method is performed according to the following steps: (1) TPA slurry enters a microchannel reactor through a heat-preserving slurry pump, a phosgene valve is opened, and the slurry enters the microchannel reactor through a mass flowmeter; (2) in a reaction process, a continuous flow microchannel reactor is used, uniform slurry of a raw material TPA is mixed with the phosgene in the reactor in proportion, a reaction is controlled to be performed in 100 DEG C through a heat exchanger; (3) a molar ratio of the TPA slurry and the phosgene is controlled to be 1:2.2, and a standing time is controlled to be 60 seconds through regulating a frequency of a slurry pump and an opening degree of a flowmeter. Two flows of the materials are mixed to react in a reaction module; (4) through regulating a counterbalance valve at an outlet of the reactor, a pressure of a reaction system is kept in 3 bar, and monitored and measured by a pressure gauge on a gas feeding pipeline; and (5) after the material passes through the microchannel reactor, a chlorination product is continuously discharged and enters a heat-preserving layering device in 85 DEG C, the upper layer is TPC liquid, a catalyst V reagent is in the lower layer, a tail gas is absorbed by connecting water and alkali. 612.0 g of an upper received material is firstly separated, 602.8 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), after 19.8 g of the yellow oily liquid V reagent separated from the lower layer is mixed with 1994.9 g of TPC liquid separated from the upper layer, a mixture is directly used for dosing and applying. A rectifying product is analyzed by UPLC: TPA is not detected, TMC is 226 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 82.0-82.3 DEG C, a total yield of the product is 98.58% (calculated by the TPA), a utilization rate of the phosgene is 91%, and a recycling rate of the catalyst is 98.2% (quantitative analysis).

Embodiment 2

[0055] 1. Preparation of raw materials: 2000 g of TPC is weighed, and put into a 2000 ml four-opening flask. The four-opening flask is placed in an oil bath of 90 DEG C for heating and melting, and 500 g of TPA (sieving in 200 meshes in advance) and 5 g of DMF are added, uniform slurry is formed by stirring and mixing for future use. A phosgene is fed into a microreactor for future use by a pipeline through a mass flowmeter, a one-way valve, a safety valve and the like.

[0056] 2. In a heart-shaped microchannel of which a material is special glass, a method is performed according to the following steps: (1) TPA slurry enters a microchannel reactor through a heat-preserving slurry pump, a phosgene valve is opened, and the slurry enters the microchannel reactor through a mass flowmeter; (2) in a reaction process, a continuous flow microchannel reactor is used, uniform slurry of a raw material TPA is mixed with the phosgene in the reactor in proportion, a reaction is controlled to be performed in 120 DEG C through a heat exchanger; (3) a molar ratio of the TPA slurry and the phosgene is controlled to be 1:2.1, and standing time is controlled to be 30 seconds through regulating a frequency of a slurry pump and an opening degree of a flowmeter, two flows of the materials are mixed to react in a reaction module; (4) through regulating a counterbalance valve at an outlet of the reactor, a pressure of a reaction system is kept in 5 bar, and monitored and measured by a pressure gauge on a gas feeding pipeline; and (5) after the material passes through the microchannel reactor, a chlorination product is continuously discharged and enters a heat-preserving layering device in 85 DEG C, the upper layer is TPC liquid, a catalyst V reagent is in the lower layer, a tail gas is absorbed by connecting water, and absorbed by alkali. 612.0 g of an upper received material is firstly separated, 600.3 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), after 9.6 g of the yellow oily liquid V reagent separated from the lower layer is mixed with 1997.7 g of TPC liquid separated from the upper layer, a mixture is directly used for dosing and applying. A rectifying product is analyzed by UPLC: TPA is not detected, TMC is 254 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 81.9-82.3 DEG C, a total yield of the product is 98.28% (calculated by the TPA), a utilization rate of the phosgene is 95.2%, and a recycling rate of the catalyst is 97.5% (quantitative analysis).

Embodiment 3

[0057] 1. Preparation of raw materials: 2000 g of TPC is weighed, and put into a 2000 ml four-opening flask. The four-opening flask is placed in an oil bath of 90 DEG C for heating and melting, and 500 g of TPA (sieving in 200 meshes in advance) and 5 g of DMF are added, uniform slurry is formed by stirring and mixing for future use. A phosgene is fed into a microreactor for future use by a pipeline through a mass flowmeter, a one-way valve, a safety valve and the like.

[0058] 2. In a heart-shaped microchannel of which a material is special glass, a method is performed according to the following steps: (1) TPA slurry enters a microchannel reactor through a heat-preserving slurry pump, a phosgene valve is opened, and the slurry enters the microchannel reactor through a mass flowmeter; (2) in a reaction process, a continuous flow microchannel reactor is used, uniform slurry of a raw material TPA is mixed with the phosgene in the reactor in proportion, a reaction is controlled to be performed in 120 DEG C through a heat exchanger; (3) a molar ratio of the TPA slurry and the phosgene is controlled to be 1:2.05, and standing time is controlled to be 60 seconds through regulating a frequency of a slurry pump and an opening degree of a flowmeter, two flows of the materials are mixed to react in a reaction module; (4) through regulating a counterbalance valve at an outlet of the reactor, a pressure of a reaction system is kept in 8bar, and monitored and measured by a pressure gauge on a gas feeding pipeline; and (5) after the material passes through the microchannel reactor, a chlorination product is continuously discharged and enters a heat-preserving layering device in 85 DEG C, the upper layer is TPC liquid, a catalyst V reagent is in the lower layer, a tail gas is absorbed by connecting water, and absorbed by alkali. 612.0 g of an upper received material is firstly separated, 603.7 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), after 9.7 g of the yellow oily liquid V reagent separated from the lower layer is mixed with 1997.6 g of TPC liquid separated from the upper layer, a mixture is directly used for dosing and applying. A rectifying product is analyzed by UPLC: TPA is not detected, TMC is 315 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 82.1-82.5 DEG C, a total yield of the product is 98.83% (calculated by the TPA), a utilization rate of the phosgene is 97.6%, and a recycling rate of the catalyst is 97.6% (quantitative analysis).

Embodiment 4

[0059] 1. Preparation of raw materials: 2007.3 g of a TPC crude product containing a catalyst which is separated in the embodiment 3 is put into a 2000 ml four-opening flask, and placed in an oil bath of 90 DEGC for heating and melting, and 500 g of TPA (content is 99.9%, and sieved in 200 meshes in advance) is added, 0.2 g of DMF is replenished, uniform slurry is formed for future use by stirring and mixing. A phosgene is fed into a microreactor for future use by a pipeline through a mass flowmeter, a one-way valve, a safety valve and the like.

[0060] 2. Reaction conditions and processes are the same as the embodiment 3, 612.0 g of an upper received material is firstly separated, 603.3 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), after 9.7 g of the yellow oily liquid V reagent separated from the lower layer is mixed with 1997.3 g of TPC liquid separated from the upper layer, a mixture is directly used for dosing and applying. A rectifying product is analyzed by UPLC: TPA is not detected, TMC is 281 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 82.0-82.2 DEG C, a total yield of the product is 98.78% (calculated by the TPA), a utilization rate of the phosgene is 97.6%, and a recycling rate of the catalyst is 97.8% (quantitative analysis).

Embodiment 5

[0061] 1. Preparation of raw materials: applying is the same as the embodiment 3, a phosgene reaction is replaced by liquid triphosgene, and a heat-preserving plunger pump is used for feeding.

[0062] 2. Reaction conditions and processes are the same as the embodiment 3, 612.0 g of an upper received material is firstly separated, 600.7 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), after 9.9 g of the yellow oily liquid V reagent separated from the lower layer is mixed with 1997.4 g of TPC liquid separated from the upper layer, a mixture is directly used for dosing and applying. A rectifying product is analyzed by UPLC: TPA is not detected, TMC is 382 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 81.9-82.5 DEG C, a total yield of the product is 98.35% (calculated by the TPA), a utilization rate of the triphosgene is 97.4%, and a recycling rate of the catalyst is 97.1% (quantitative analysis).

Embodiment 6

[0063] 1. Preparation of raw materials: 2007.3 g of a TPC crude product containing a catalyst which is separated in the embodiment 5 is applied, and put into a 2000 ml four-opening flask, and placed in an oil bath of 90 DEG C for heating and melting. 500 g of TPA (content is 99.9%, and sieved in 200 meshes in advance) is added, 0.29 g of DMF is replenished, uniform slurry is formed for future use by stirring and mixing. A phosgene reaction is replaced by liquid triphosgene, and a heat-preserving plunger pump is used for feeding.

[0064] 2. Reaction conditions and processes are the same as the embodiment 5, 612.0 g of an upper received material is firstly separated, 603.8 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), after 10.0 g of the yellow oily liquid V reagent separated from the lower layer is mixed with 1996.9 g of TPC liquid separated from the upper layer, a mixture is directly used for dosing and applying. A rectifying product is analyzed by UPLC: TPA is not detected, TMC is 363 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 82.1-82.4 DEG C, a total yield of the product is 98.85% (calculated by the TPA), a utilization rate of the triphosgene is 96.9%, and a recycling rate of the catalyst is 97.9% (quantitative analysis).

Embodiment 7

[0065] 1. Preparation of raw materials: applying is the same as the embodiment 3, a difference is as follows: after TPC is weighed, the TPC is put into a four-opening flask, and placed in an oil bath of 100 DEG C for heating and melting, and TPA and DMF are added, uniform slurry is formed for future use by stirring and mixing. A solid triphosgene is melted in 90 DEG C to form liquid triphosgene.

[0066] 2. Reaction conditions and processes are the same as the embodiment 3, a difference is as follows: a reaction temperature is 145 DEG C, and reaction standing time is 10 s.

[0067] 612.0 g of an upper received material is firstly separated, 596.7 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), after 12.9 g of the yellow oily liquid V reagent separated from the lower layer is mixed with 1992.4 g of TPC liquid separated from the upper layer, a mixture is directly used for dosing and applying. A rectifying product is analyzed by UPLC: TPA is not detected, TMC is 400 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 82.1-82.6 DEG C, a total yield of the product is 96.83% (calculated by the TPA), a utilization rate of the triphosgene is 87.4%, and a recycling rate of the catalyst is 95.1% (quantitative analysis).

Contrast Example 1

[0068] 1. Device: a kettle-type reaction.

[0069] 2. Reaction: 180 g of TPC, 60 g of TPA (99.9%), and 1.8 g of DMF (99.9%) are put into a 250 ml four-opening flask, and heated to 87 DEG C, uniform slurry is formed by mixing. A phosgene is fed into a reaction flask through a mass flowmeter, a flow is about 20 g/h. The reaction is performed in 90 DEG C until the slurry becomes pale yellow clear liquid, and the reaction is stopped. Reaction time is about 6 hours, 111.2 g of phosgene is fed totally, and 255.1 g of a material is received totally. 3.2 g of a black viscous liquid V reagent is separated from the lower layer, and 73.5 g of TPC liquid is taken from the upper layer, 68.35 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), analyzed by UPLC: TPA is not detected, TMC is 812 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 81.9-82.2 DEG C, a total yield of the product is 93.25% (calculated by the TPA), a utilization rate of the phosgene is 64.3%, and a recycling rate of the catalyst is 65.52% (quantitative analysis).

Contrast Example 2

[0070] 1. Device: a Kettle-Type Reaction.

[0071] 2. Reaction: 100 g of TPC, 25 g of TPA (99.9%), and 0.75 g of DMF (99.9%) are put into a 250 ml four-opening flask, and heated to 95 DEG C, uniform slurry is formed by mixing. A phosgene is fed into a reaction flask through a mass flowmeter, a flow is about 10 g/h. The reaction is performed in 98 DEG C until the slurry becomes pale yellow clear liquid, and the reaction is stopped. Reaction time is about 4.5 hours, 43.1 g of phosgene is fed totally, and 131.4 g of a material is received totally, 1.2 g of a black viscous liquid V reagent is separated from the lower layer, and 30.6 g of TPC liquid is taken from the upper layer, 28.5 g of a fraction is collected in 128-130 DEG C through rectification under vacuum (12-13 mmHg), analyzed by UPLC: TPA is not detected, TMC is 726 ppm, gas chromatography TPC is greater than 99.9%, a melting range is 82-82.3 DEG C, a total yield of the product is 93.15% (calculated by the TPA), a utilization rate of the phosgene is 69.2%, and a recycling rate of the catalyst is 43.48% (quantitative analysis).

[0072] Table 1 is quality indexes of industrial paraphthaloyl chloride

TABLE-US-00001 Index Superior Top quality Project products products Paraphthaloyl chloride w % 99.9 99.6 Terephthalic acid w % 0.01 Isophthaloyl dichloride w % 0.01 Sum of other impurities w % 0.08 0.30 Melting point DEG C. 82-83

[0073] The above are merely preferable embodiments of the disclosure, and are not used for limiting the disclosure. It may be understood by those skilled in the art that the disclosure may have various changes and variations. All of any modifications, equivalent replacements, improvements and the like made within spirit and principles of the disclosure shall fall within a scope of protection of the disclosure.