CN116283595A - Method for synthesizing o-nitrotoluene by adopting microchannel reaction device - Google Patents
Method for synthesizing o-nitrotoluene by adopting microchannel reaction device Download PDFInfo
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- CN116283595A CN116283595A CN202310265877.2A CN202310265877A CN116283595A CN 116283595 A CN116283595 A CN 116283595A CN 202310265877 A CN202310265877 A CN 202310265877A CN 116283595 A CN116283595 A CN 116283595A
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- reaction
- nitrotoluene
- reaction device
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- 238000006243 chemical reaction Methods 0.000 title claims abstract description 111
- PLAZTCDQAHEYBI-UHFFFAOYSA-N 2-nitrotoluene Chemical compound CC1=CC=CC=C1[N+]([O-])=O PLAZTCDQAHEYBI-UHFFFAOYSA-N 0.000 title claims abstract description 51
- 238000000034 method Methods 0.000 title claims abstract description 19
- 230000002194 synthesizing effect Effects 0.000 title claims abstract description 14
- YXFVVABEGXRONW-UHFFFAOYSA-N Toluene Chemical compound CC1=CC=CC=C1 YXFVVABEGXRONW-UHFFFAOYSA-N 0.000 claims abstract description 93
- 239000002994 raw material Substances 0.000 claims abstract description 27
- 239000012074 organic phase Substances 0.000 claims abstract description 23
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 23
- 238000005406 washing Methods 0.000 claims abstract description 18
- SCYULBFZEHDVBN-UHFFFAOYSA-N 1,1-Dichloroethane Chemical compound CC(Cl)Cl SCYULBFZEHDVBN-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000002253 acid Substances 0.000 claims abstract description 16
- 238000001914 filtration Methods 0.000 claims abstract description 13
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 claims abstract description 10
- 238000002156 mixing Methods 0.000 claims abstract description 9
- 239000012071 phase Substances 0.000 claims abstract description 9
- 238000001514 detection method Methods 0.000 claims abstract description 8
- 239000012528 membrane Substances 0.000 claims abstract description 8
- 239000012295 chemical reaction liquid Substances 0.000 claims abstract description 5
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 14
- 239000007788 liquid Substances 0.000 claims description 13
- 230000007935 neutral effect Effects 0.000 claims description 7
- 230000035484 reaction time Effects 0.000 claims description 3
- 239000000047 product Substances 0.000 abstract description 15
- 239000006227 byproduct Substances 0.000 abstract description 3
- 238000003786 synthesis reaction Methods 0.000 abstract description 3
- 238000012546 transfer Methods 0.000 abstract description 3
- 238000002347 injection Methods 0.000 description 4
- 239000007924 injection Substances 0.000 description 4
- 239000000243 solution Substances 0.000 description 4
- 239000007858 starting material Substances 0.000 description 4
- 238000006396 nitration reaction Methods 0.000 description 2
- 238000013021 overheating Methods 0.000 description 2
- 238000003756 stirring Methods 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- QZYHIOPPLUPUJF-UHFFFAOYSA-N 3-nitrotoluene Chemical compound CC1=CC=CC([N+]([O-])=O)=C1 QZYHIOPPLUPUJF-UHFFFAOYSA-N 0.000 description 1
- ZPTVNYMJQHSSEA-UHFFFAOYSA-N 4-nitrotoluene Chemical compound CC1=CC=C([N+]([O-])=O)C=C1 ZPTVNYMJQHSSEA-UHFFFAOYSA-N 0.000 description 1
- 229910002651 NO3 Inorganic materials 0.000 description 1
- NHNBFGGVMKEFGY-UHFFFAOYSA-N Nitrate Chemical compound [O-][N+]([O-])=O NHNBFGGVMKEFGY-UHFFFAOYSA-N 0.000 description 1
- 230000006978 adaptation Effects 0.000 description 1
- 238000007792 addition Methods 0.000 description 1
- 239000012752 auxiliary agent Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000011161 development Methods 0.000 description 1
- 239000003814 drug Substances 0.000 description 1
- 229940079593 drug Drugs 0.000 description 1
- 239000000975 dye Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 238000011010 flushing procedure Methods 0.000 description 1
- 231100000053 low toxicity Toxicity 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- VLZLOWPYUQHHCG-UHFFFAOYSA-N nitromethylbenzene Chemical compound [O-][N+](=O)CC1=CC=CC=C1 VLZLOWPYUQHHCG-UHFFFAOYSA-N 0.000 description 1
- 239000000049 pigment Substances 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 239000000376 reactant Substances 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C201/00—Preparation of esters of nitric or nitrous acid or of compounds containing nitro or nitroso groups bound to a carbon skeleton
- C07C201/06—Preparation of nitro compounds
- C07C201/08—Preparation of nitro compounds by substitution of hydrogen atoms by nitro groups
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to the field of organic synthesis, and discloses a method for synthesizing o-nitrotoluene by adopting a microchannel reaction device, which comprises the following steps: (1) Washing the interior of the microchannel reaction device for a plurality of times, and correcting the flow of the feed pump; (2) Mixing dichloroethane and fuming nitric acid according to a certain volume ratio to obtain a raw material A; (3) Adjusting the reaction temperature of the micro-channel reaction device, and adding toluene into a reaction cavity of the micro-channel reaction device through a toluene inlet pump; adding a raw material A into a reaction cavity of a micro-channel reaction device through an acid inlet pump; (4) After a period of reaction, the reaction liquid flows out from the tail end of the micro-channel reaction device, namely the primary o-nitrotoluene; (5) And (3) placing the o-nitrotoluene in water, separating an organic phase, washing the organic phase with water for a plurality of times, filtering the organic phase by a filtering membrane to obtain an o-nitrotoluene finished product, and performing gas phase detection. The method can accurately control the reaction temperature and time, and has the advantages of high transfer rate, short contact time and few byproducts.
Description
Technical Field
The invention relates to the field of organic synthesis, in particular to a method for synthesizing o-nitrotoluene by adopting a microchannel reaction device.
Background
Nitrotoluene is a production intermediate for producing various fine chemicals, has wide industrial application, is formed by mixing three isomers of ortho-nitrotoluene, meta-nitrotoluene and para-nitrotoluene (abbreviated as mixed nitrate), and the three separated pure products are all important synthetic raw materials for organic chemical industry. The pure products have the characteristic of low toxicity and are widely used in organic synthesis industries such as dyes, pigments, plastics, medicines, fibers, auxiliary agents and the like. In recent years, with the continuous development of the international and domestic chemical industries, the market demand for the three isomers has been strongly increased. In the prior art, the nitration reaction has severe heat release, large heat and difficult control of temperature; the nitration reaction is a two-phase reaction, and local overheating and insufficient reaction caused by uneven stirring are easy to occur. And the byproducts are more, so that the next step of separation and purification is not easy to carry out.
Disclosure of Invention
The invention aims to provide a method for synthesizing o-nitrotoluene by adopting a microchannel reaction device, wherein the microchannel reaction device has good mass transfer effect, the contact of reaction liquid is more uniform, the reaction is more thoroughly carried out, and the problems of local overheating and insufficient reaction caused by uneven stirring are solved.
In order to achieve the above purpose, the invention is realized by adopting the following technical scheme:
a method for synthesizing o-nitrotoluene by adopting a microchannel reaction device comprises the following steps:
(1) Washing the interior of the microchannel reaction device for a plurality of times, and correcting the flow of the toluene inlet pump and the acid inlet pump;
(2) Preparing raw materials: mixing dichloroethane and fuming nitric acid according to a certain volume ratio to obtain a raw material A;
(3) The micro-channel reaction device is connected with the cold-heat exchange integrated machine, the cold-heat exchange integrated machine controls the reaction temperature, so that the temperature in the micro-channel reactor is kept stable, after the temperature is stable, toluene is added into a reaction cavity of the micro-channel reaction device through a toluene inlet pump, and raw material A is added into the reaction cavity of the micro-channel reaction device through an acid inlet pump; raw material A reacts with toluene in a reaction cavity;
(4) After a period of reaction, the reaction liquid flows out from the tail end of the micro-channel reaction device, namely the primary o-nitrotoluene;
(5) Placing o-nitrotoluene in 5-50ml of water, separating an organic phase, placing the organic phase in 20ml of water, washing the organic phase for multiple times, filtering the organic phase by a filter membrane to obtain an o-nitrotoluene finished product, and taking the o-nitrotoluene finished product for gas phase detection;
(6) After the reaction is finished, the effluent liquid in the micro-channel is washed by water until the effluent liquid is neutral, and the toluene inlet pump and the acid inlet pump are filled with ethanol.
Preferably, the step (1) is performed with a plurality of washings using dichloroethane.
Preferably, the volume ratio of dichloroethane to fuming nitric acid in the step (2) is 1 (1-3).
Preferably, the reaction temperature of the microchannel reactor in the step (3) is 68-75 ℃.
Preferably, the feeding speed of the toluene feeding pump in the step (3) is 8.31-8.51ml/min, and the feeding speed of the acid feeding pump is 11.49-12.51ml/min.
Preferably, the reaction time in the step (4) is 6-12min.
The beneficial effects of the invention are as follows:
the invention discloses a method for synthesizing o-nitrotoluene by adopting a microchannel reaction device, which uses microchannel equipment to synthesize the o-nitrotoluene, can accurately control the reaction temperature, the reaction time and the material proportion, and has the advantages of large specific surface area of reaction contact, high transfer rate, short contact time of reactants and few byproducts. Meanwhile, a large amount of heat can be removed in time, so that the safety is high, the reaction temperature is ensured to be maintained within a set range, and the possibility of accidents is greatly reduced. The microchannel reaction device is a parallel system with a modular structure and has good operability.
Detailed Description
The invention is further illustrated by the following examples:
a method for synthesizing o-nitrotoluene by adopting a microchannel reaction device comprises the following steps:
(1) Washing the interior of the microchannel reaction device for a plurality of times, and correcting the flow of the toluene inlet pump and the acid inlet pump;
(2) Preparing raw materials: mixing dichloroethane and fuming nitric acid according to a certain volume ratio to obtain a raw material A;
(3) The micro-channel reaction device is connected with the cold-heat exchange integrated machine, the cold-heat exchange integrated machine controls the reaction temperature, so that the temperature in the micro-channel reactor is kept stable, after the temperature is stable, toluene is added into a reaction cavity of the micro-channel reaction device through a toluene inlet pump, and raw material A is added into the reaction cavity of the micro-channel reaction device through an acid inlet pump; raw material A reacts with toluene in a reaction cavity;
(4) After a period of reaction, the reaction liquid flows out from the tail end of the micro-channel reaction device, namely the primary o-nitrotoluene;
(5) Placing o-nitrotoluene in 5-50ml of water, separating an organic phase, placing the organic phase in 20ml of water, washing the organic phase for multiple times, filtering the organic phase by a filter membrane to obtain an o-nitrotoluene finished product, and taking the o-nitrotoluene finished product for gas phase detection;
(6) After the reaction is finished, the effluent liquid in the micro-channel is washed by water until the effluent liquid is neutral, and the toluene inlet pump and the acid inlet pump are filled with ethanol.
Example 1
The dichloroethane is used for washing the inside of the channel reaction device for a plurality of times, and the flow rate of the feed pump is corrected; the method comprises the steps of mixing dichloroethane and fuming nitric acid according to a volume ratio of 1:3 to obtain a raw material A, connecting a microchannel reaction device with a cold-heat exchange integrated machine, controlling the reaction temperature by the cold-heat exchange integrated machine to ensure that the temperature in a microchannel reactor is kept stable, beginning sample injection when the temperature is stabilized at 68 ℃, adding toluene into a reaction cavity of the microchannel reaction device at a feeding speed of 8.31ml/min by a toluene inlet pump, adding the raw material A into the reaction cavity of the microchannel reaction device at a feeding speed of 12.51ml/min by an acid inlet pump, reacting the raw material A with toluene in the reaction cavity for 7min, flowing out a reaction solution at the tail end of the microchannel reaction device to obtain primary ortho-nitrotoluene, taking the ortho-nitrotoluene to be placed in 5-50ml of water, separating an organic phase, placing in 20ml of water, washing for many times, filtering the organic phase by a filtering membrane to obtain an ortho-nitrotoluene finished product, and taking the ortho-nitrotoluene finished product for gas phase detection. The yield of ortho-nitrotoluene was 40%, with a conversion of the starting material of 98.2368%. After the reaction is finished, the effluent liquid in the micro-channel is washed by water until the effluent liquid is neutral, and the pump is filled with ethanol.
Example 2
The dichloroethane is used for washing the inside of the channel reaction device for a plurality of times, and the flow rate of the feed pump is corrected; the method comprises the steps of mixing dichloroethane and fuming nitric acid according to a volume ratio of 1:3 to obtain a raw material A, connecting a microchannel reaction device with a cold-heat exchange integrated machine, controlling the reaction temperature by the cold-heat exchange integrated machine to ensure that the temperature in a microchannel reactor is kept stable, beginning sample injection when the temperature is kept at 70 ℃, adding toluene into a reaction cavity of the microchannel reaction device at a feeding speed of 8.40ml/min by a toluene inlet pump, adding the raw material A into the reaction cavity of the microchannel reaction device at a feeding speed of 11.80ml/min by an acid inlet pump, reacting the raw material A with toluene in the reaction cavity for 12min, flowing out a reaction solution at the tail end of the microchannel reaction device to obtain primary ortho-nitrotoluene, taking the ortho-nitrotoluene to be placed in 5-50ml of water, separating an organic phase, placing in 20ml of water, washing for many times, filtering the organic phase by a filtering membrane to obtain an ortho-nitrotoluene finished product, and taking the ortho-nitrotoluene finished product for gas phase detection. The yield of ortho-nitrotoluene was 45%, with a conversion of the starting material of 90.1728%. After the reaction is finished, the effluent liquid in the micro-channel is washed by water until the effluent liquid is neutral, and the pump is filled with ethanol.
Example 3
The dichloroethane is used for washing the inside of the channel reaction device for a plurality of times, and the flow rate of the feed pump is corrected; the method comprises the steps of mixing dichloroethane and fuming nitric acid according to a volume ratio of 1:1 to obtain a raw material A, connecting a microchannel reaction device with a cold-heat exchange integrated machine, controlling the reaction temperature by the cold-heat exchange integrated machine to ensure that the temperature in a microchannel reactor is kept stable, beginning sample injection when the temperature is kept at 70 ℃, adding toluene into a reaction cavity of the microchannel reaction device at a feeding speed of 8.51ml/min by a toluene inlet pump, adding the raw material A into the reaction cavity of the microchannel reaction device at a feeding speed of 11.49ml/min by an acid inlet pump, reacting the raw material A with toluene in the reaction cavity for 6min, flowing out a reaction solution at the tail end of the microchannel reaction device to obtain primary ortho-nitrotoluene, taking the ortho-nitrotoluene to be placed in 5-50ml of water, separating an organic phase, placing in 20ml of water, washing for many times, filtering the organic phase by a filtering membrane to obtain an ortho-nitrotoluene finished product, and taking the ortho-nitrotoluene finished product for gas phase detection. The yield of ortho-nitrotoluene was 20%, with a conversion of the starting material of 56.2085%. After the reaction is finished, the effluent liquid in the micro-channel is washed by water until the effluent liquid is neutral, and the pump is filled with ethanol.
Example 4
The dichloroethane is used for washing the inside of the channel reaction device for a plurality of times, and the flow rate of the feed pump is corrected; the method comprises the steps of mixing dichloroethane and fuming nitric acid according to a volume ratio of 1:1 to obtain a raw material A, connecting a microchannel reaction device with a cold-heat exchange integrated machine, controlling the reaction temperature by the cold-heat exchange integrated machine to ensure that the temperature in a microchannel reactor is kept stable, beginning sample injection when the temperature is kept at 75 ℃, adding toluene into a reaction cavity of the microchannel reaction device at a feeding speed of 8.51ml/min by a toluene inlet pump, adding the raw material A into the reaction cavity of the microchannel reaction device at a feeding speed of 11.49ml/min by an acid inlet pump, reacting the raw material A with toluene in the reaction cavity for 10min, flowing out a reaction solution at the tail end of the microchannel reaction device to obtain primary ortho-nitrotoluene, taking the ortho-nitrotoluene to be placed in 5-50ml of water, separating an organic phase, placing in 20ml of water, washing for many times, filtering the organic phase by a filtering membrane to obtain an ortho-nitrotoluene finished product, and taking the ortho-nitrotoluene finished product for gas phase detection. The yield of ortho-nitrotoluene was 30%, where the conversion of the starting material was 58.9632% after the reaction was completed, the effluent liquid in the microchannel was neutral by flushing with water, and the pump was filled with ethanol.
It should be understood that the above description is not intended to limit the invention to the particular embodiments disclosed, but to limit the invention to the particular embodiments disclosed, and that the invention is not limited to the particular embodiments disclosed, but is intended to cover modifications, adaptations, additions and alternatives falling within the spirit and scope of the invention.
Claims (6)
1. A method for synthesizing o-nitrotoluene by adopting a microchannel reaction device is characterized by comprising the following steps:
(1) Washing the interior of the microchannel reaction device for a plurality of times, and correcting the flow of the toluene inlet pump and the acid inlet pump;
(2) Preparing raw materials: mixing dichloroethane and fuming nitric acid according to a certain volume ratio to obtain a raw material A;
(3) The micro-channel reaction device is connected with the cold-heat exchange integrated machine, the cold-heat exchange integrated machine controls the reaction temperature, so that the temperature in the micro-channel reactor is kept stable, after the temperature is stable, toluene is added into a reaction cavity of the micro-channel reaction device through a toluene inlet pump, and raw material A is added into the reaction cavity of the micro-channel reaction device through an acid inlet pump; raw material A reacts with toluene in a reaction cavity;
(4) After a period of reaction, the reaction liquid flows out from the tail end of the micro-channel reaction device, namely the primary o-nitrotoluene;
(5) Placing o-nitrotoluene in 5-50ml of water, separating an organic phase, placing the organic phase in 20ml of water, washing the organic phase for multiple times, filtering the organic phase by a filter membrane to obtain an o-nitrotoluene finished product, and taking the o-nitrotoluene finished product for gas phase detection;
(6) After the reaction is finished, the effluent liquid in the micro-channel is washed by water until the effluent liquid is neutral, and the toluene inlet pump and the acid inlet pump are filled with ethanol.
2. The method for synthesizing o-nitrotoluene using a microchannel reactor according to claim 1, wherein the step (1) is performed with a plurality of washings with dichloroethane.
3. The method for synthesizing o-nitrotoluene by using a microchannel reactor according to claim 1, wherein the volume ratio of dichloroethane to fuming nitric acid in step (2) is 1 (1-3).
4. The method for synthesizing o-nitrotoluene using a microchannel reactor according to claim 1, wherein the reaction temperature of the microchannel reactor in step (3) is 68-75 ℃.
5. The method for synthesizing o-nitrotoluene by using a microchannel reactor according to claim 1, wherein the feeding speed of the toluene feeding pump in the step (3) is 8.31-8.51ml/min, and the feeding speed of the acid feeding pump is 11.49-12.51ml/min.
6. The method for synthesizing o-nitrotoluene using a microchannel reactor according to claim 1, wherein the reaction time in step (4) is 6-12min.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310265877.2A CN116283595A (en) | 2023-03-20 | 2023-03-20 | Method for synthesizing o-nitrotoluene by adopting microchannel reaction device |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202310265877.2A CN116283595A (en) | 2023-03-20 | 2023-03-20 | Method for synthesizing o-nitrotoluene by adopting microchannel reaction device |
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| CN116283595A true CN116283595A (en) | 2023-06-23 |
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| CN202310265877.2A Pending CN116283595A (en) | 2023-03-20 | 2023-03-20 | Method for synthesizing o-nitrotoluene by adopting microchannel reaction device |
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