CN111170871A - Method for synthesizing 6-bromo-2, 4-dinitroaniline - Google Patents
Method for synthesizing 6-bromo-2, 4-dinitroaniline Download PDFInfo
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- CN111170871A CN111170871A CN201911393067.5A CN201911393067A CN111170871A CN 111170871 A CN111170871 A CN 111170871A CN 201911393067 A CN201911393067 A CN 201911393067A CN 111170871 A CN111170871 A CN 111170871A
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- 238000000034 method Methods 0.000 title claims abstract description 50
- KWMDHCLJYMVBNS-UHFFFAOYSA-N 2-bromo-4,6-dinitroaniline Chemical compound NC1=C(Br)C=C([N+]([O-])=O)C=C1[N+]([O-])=O KWMDHCLJYMVBNS-UHFFFAOYSA-N 0.000 title claims abstract description 36
- 230000002194 synthesizing effect Effects 0.000 title claims abstract description 20
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims abstract description 109
- 238000006243 chemical reaction Methods 0.000 claims abstract description 80
- MHAJPDPJQMAIIY-UHFFFAOYSA-N Hydrogen peroxide Chemical compound OO MHAJPDPJQMAIIY-UHFFFAOYSA-N 0.000 claims abstract description 76
- 239000012452 mother liquor Substances 0.000 claims abstract description 45
- LXQOQPGNCGEELI-UHFFFAOYSA-N 2,4-dinitroaniline Chemical compound NC1=CC=C([N+]([O-])=O)C=C1[N+]([O-])=O LXQOQPGNCGEELI-UHFFFAOYSA-N 0.000 claims abstract description 37
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 claims abstract description 36
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 claims abstract description 32
- 229910052794 bromium Inorganic materials 0.000 claims abstract description 32
- 238000004321 preservation Methods 0.000 claims abstract description 22
- 239000000047 product Substances 0.000 claims abstract description 17
- 238000005119 centrifugation Methods 0.000 claims abstract description 15
- 239000012065 filter cake Substances 0.000 claims abstract description 11
- 238000000227 grinding Methods 0.000 claims abstract description 10
- 238000003756 stirring Methods 0.000 claims abstract description 10
- 238000010438 heat treatment Methods 0.000 claims abstract description 5
- 229910000041 hydrogen chloride Inorganic materials 0.000 claims description 18
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 claims description 18
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 13
- 238000004064 recycling Methods 0.000 claims description 9
- 238000000926 separation method Methods 0.000 claims description 8
- 239000000126 substance Substances 0.000 claims description 8
- 239000000084 colloidal system Substances 0.000 claims description 6
- 238000001035 drying Methods 0.000 claims description 6
- 238000002360 preparation method Methods 0.000 claims description 5
- 239000002994 raw material Substances 0.000 claims description 5
- 230000035484 reaction time Effects 0.000 claims description 5
- 239000000463 material Substances 0.000 claims description 4
- 239000010413 mother solution Substances 0.000 claims description 4
- 239000011541 reaction mixture Substances 0.000 claims description 4
- 238000001914 filtration Methods 0.000 claims description 3
- 238000011084 recovery Methods 0.000 claims description 3
- 238000005070 sampling Methods 0.000 claims description 3
- 238000000967 suction filtration Methods 0.000 claims description 3
- 239000012535 impurity Substances 0.000 claims description 2
- 238000002156 mixing Methods 0.000 claims description 2
- 238000004519 manufacturing process Methods 0.000 abstract description 8
- 239000002351 wastewater Substances 0.000 abstract description 5
- 125000004122 cyclic group Chemical group 0.000 abstract 1
- 230000001105 regulatory effect Effects 0.000 abstract 1
- CPELXLSAUQHCOX-UHFFFAOYSA-N Hydrogen bromide Chemical compound Br CPELXLSAUQHCOX-UHFFFAOYSA-N 0.000 description 12
- 229910000042 hydrogen bromide Inorganic materials 0.000 description 6
- 239000000243 solution Substances 0.000 description 6
- 239000007800 oxidant agent Substances 0.000 description 5
- 230000001590 oxidative effect Effects 0.000 description 5
- 230000002378 acidificating effect Effects 0.000 description 4
- 230000008901 benefit Effects 0.000 description 4
- BZSXEZOLBIJVQK-UHFFFAOYSA-N 2-methylsulfonylbenzoic acid Chemical compound CS(=O)(=O)C1=CC=CC=C1C(O)=O BZSXEZOLBIJVQK-UHFFFAOYSA-N 0.000 description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 description 2
- 239000005708 Sodium hypochlorite Substances 0.000 description 2
- 230000015572 biosynthetic process Effects 0.000 description 2
- 238000005893 bromination reaction Methods 0.000 description 2
- 239000006227 byproduct Substances 0.000 description 2
- 239000000460 chlorine Substances 0.000 description 2
- 229910052801 chlorine Inorganic materials 0.000 description 2
- 238000004128 high performance liquid chromatography Methods 0.000 description 2
- 239000007788 liquid Substances 0.000 description 2
- 238000005086 pumping Methods 0.000 description 2
- 239000000376 reactant Substances 0.000 description 2
- 150000003839 salts Chemical class 0.000 description 2
- SUKJFIGYRHOWBL-UHFFFAOYSA-N sodium hypochlorite Chemical compound [Na+].Cl[O-] SUKJFIGYRHOWBL-UHFFFAOYSA-N 0.000 description 2
- 238000001308 synthesis method Methods 0.000 description 2
- 238000003786 synthesis reaction Methods 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000001514 detection method Methods 0.000 description 1
- 239000000986 disperse dye Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000005516 engineering process Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 238000000643 oven drying Methods 0.000 description 1
Classifications
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C209/00—Preparation of compounds containing amino groups bound to a carbon skeleton
- C07C209/68—Preparation of compounds containing amino groups bound to a carbon skeleton from amines, by reactions not involving amino groups, e.g. reduction of unsaturated amines, aromatisation, or substitution of the carbon skeleton
- C07C209/74—Preparation of compounds containing amino groups bound to a carbon skeleton from amines, by reactions not involving amino groups, e.g. reduction of unsaturated amines, aromatisation, or substitution of the carbon skeleton by halogenation, hydrohalogenation, dehalogenation, or dehydrohalogenation
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- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention discloses a method for synthesizing 6-bromo-2, 4-dinitroaniline, which comprises the steps of grinding 2, 4-dinitroaniline, and adding the ground 2, 4-dinitroaniline into a reaction kettle; then adding the recycled mother liquor regulated by hydrochloric acid, adjusting the mass concentration of HCl to 3-10%, heating to 35-60 ℃, and stirring for 1-2 hours while keeping the temperature; then adding bromine into the reaction kettle at the temperature of 35-60 ℃; then carrying out heat preservation reaction for 1-2.5 hours; heating the reaction kettle to 60-85 ℃, dropwise adding hydrogen peroxide, and carrying out heat preservation reaction at 80 +/-5 ℃ for 1-2 hours; the mother liquor after centrifugation can replace hydrochloric acid for cyclic utilization; the filter cake is dried to obtain the product 6-bromo-2, 4-dinitroaniline. The method belongs to an environment-friendly production process, the product obtained by the process has high purity and high production efficiency, and the mother liquor can be continuously recycled, so that zero discharge of wastewater is realized.
Description
Technical Field
The invention relates to a 6-bromo-2, 4-dinitroaniline technology, in particular to a method for synthesizing 6-bromo-2, 4-dinitroaniline.
Background
The 6-bromo-2, 4-dinitroaniline is an important intermediate of disperse dyes, the using amount is large at home and abroad, and the method generally takes 2, 4-dinitroaniline, hydrochloric acid, water and bromine as raw materials and then drops an oxidant for preparation. The oxidant mainly comprises sodium chlorate, sodium hypochlorite and chlorine.
1) Using sodium chlorate as oxidant
The method has mature process, high product purity up to 98.5%, short reaction time and high unit yield. But the salt-containing low-acidity acidic wastewater generated in the reaction process cannot be continuously recycled.
2) Sodium hypochlorite as oxidant
The method has the advantages of complex production process, byproduct generation, poor product quality, deep color, long reaction time and low equipment utilization rate, generates the salty low-acidity acidic wastewater, and cannot be continuously recycled.
3) Chlorine is used as an oxidant, and by-products are generated in the production process of the method, the equipment requirement is high, and high-acidity acidic water is generated.
In order to solve the problems, a new environment-friendly production process needs to be developed, so that the economic benefit is improved, the efficiency of recycling mother liquor is improved, the wastewater discharge is reduced, the subsequent treatment cost is reduced, and the clean production is realized.
Disclosure of Invention
The technical problem to be solved by the invention is to provide a method for synthesizing 6-bromo-2, 4-dinitroaniline,
in order to solve the technical problems, the invention adopts the following technical scheme:
a method for synthesizing 6-bromo-2, 4-dinitroaniline comprises the following steps:
step A1: grinding and material preparation: grinding 2, 4-dinitroaniline with the mass purity of more than 99.85 percent by a colloid mill, and adding the ground 2, 4-dinitroaniline into a reaction kettle;
step A2: a hydrochloric acid adding procedure: adding hydrochloric acid and water into a reaction kettle, raising the temperature to 35-60 ℃, and stirring for 1-2 hours under heat preservation; finally, controlling the concentration of hydrochloric acid to be 3% -10%, wherein the quantity ratio of 2, 4-dinitroaniline to HCl is 1: 4-9;
more specifically, the hydrochloric acid concentration is 3% -10%, which means the hydrochloric acid concentration of 2, 4-dinitroaniline is not included.
Step A3: adding bromine: adding bromine into a reaction kettle, and controlling the temperature to be 35-60 ℃ in the dropwise adding process; the mass ratio of the 2, 4-dinitroaniline to the bromine substance is 1: 0.51-0.52;
preferably, the bromine feeding temperature is controlled to be 35-60 ℃;
more specifically, the bromine is liquid bromine with the chemical formula of Br2。
Step A4: a low-temperature reaction process: after the bromine addition is finished, controlling the temperature to be 45 +/-5 ℃, and carrying out heat preservation reaction for 1-2.5 hours;
step A5: adding hydrogen peroxide: and (3) raising the temperature in the reaction kettle to 60-85 ℃, then dropwise adding hydrogen peroxide, and controlling the temperature to be 80 +/-5 ℃ in the dropwise adding process.
More specifically, before dropwise adding hydrogen peroxide, the temperature of the reaction kettle is raised to 60-85 ℃, the temperature is controlled to be 80 +/-5 ℃ in the dropwise adding process, and the quantity ratio of the 2, 4-dinitroaniline to the hydrogen peroxide is 1: 0.52-0.8; more specifically, in the step A5, the hydrogen peroxide is dropwise added for 3-6 hours;
step A6: a high-temperature reaction process: after the dropwise addition of the hydrogen peroxide is finished, controlling the temperature to be 80 +/-5 ℃, carrying out heat preservation reaction for 1-2 hours, and entering a centrifugation process after the reaction is finished; or the reaction time takes the reaction end point of 6-bromo-2, 4-dinitroaniline with the content higher than 98.5 percent after sampling and centrifugal separation, and then the reaction enters a centrifugal process;
step A7: a centrifugation step: after the heat preservation is finished, carrying out centrifugal separation on the reaction mixture to obtain a filter cake and a mother solution;
step A8: a drying procedure: after centrifugation, the filter cake is dried to obtain the product 6-bromo-2, 4-dinitroaniline.
Preferably, after suction filtration, the mother liquor is filtered and then sent to a recovery tank to replace hydrochloric acid for recycling. More specifically, after the mother liquor absorbs hydrogen chloride or is added with concentrated hydrochloric acid, the mass concentration calculated by HCl reaches 3% -10%, and the mother liquor is added into step A2 in the synthesis process instead of the concentrated hydrochloric acid for recycling.
More specifically, in the step A2-the step A6, the reaction kettle is in a stirring state.
A method for synthesizing 6-bromo-2, 4-dinitroaniline comprises the following steps:
step B1: mother liquor concentration blending process: adding the mother liquor into a reaction kettle, and if the concentration of hydrochloric acid is lower than 3%, adding concentrated hydrochloric acid to adjust the calculated mass concentration of HCl to 3-10%;
the mother liquor comprises the following components: comprises 3 to 10 mass percent of hydrogen chloride, 0.01 to 0.03 mass percent of hydrogen peroxide, unreacted 2, 4-dinitroaniline dissolved in hydrochloric acid, and the balance of water and indispensable impurities;
more specifically, the mother liquor is the mother liquor obtained in the step A7 or the mother liquor obtained in the step B8 by recycling;
step B2: grinding and material preparation: grinding 2, 4-dinitroaniline with the mass purity of more than 99.85 percent by a colloid mill, and adding the ground 2, 4-dinitroaniline into a reaction kettle;
step B3: adding mother liquor and hydrochloric acid: preferentially adding the mother liquor prepared in the step B1 into the reaction kettle, and adding hydrochloric acid and water when the mother liquor is insufficient, so that the final reaction kettle comprises the following raw materials: the concentration of the hydrochloric acid is 3% -10%, and the mass ratio of the 2, 4-dinitroaniline to the HCl substance is 1: 4-9; raising the temperature to 35-60 ℃, and stirring for 1-2 hours under heat preservation;
more specifically, the hydrochloric acid concentration is 3% -10%, which means the hydrochloric acid concentration of 2, 4-dinitroaniline is not included;
and step B4: adding bromine: adding bromine into the reaction kettle after the step B3 is finished, and controlling the temperature to be 35-60 ℃ in the dropwise adding process; so that the 2, 4-dinitroaniline and Br are added into the reaction kettle according to the theoretical amount2The mass ratio of the substances is 1: 0.51-0.52;
preferably, the bromine feeding temperature is controlled to be 35-60 ℃;
more specifically, the bromine is liquid bromine with the chemical formula of Br2；
Step B5: a low-temperature reaction process: after the bromine addition is finished, controlling the temperature to be 45 +/-5 ℃, and carrying out heat preservation reaction for 1-2.5 hours;
step B6: adding hydrogen peroxide: heating the temperature in the reaction kettle to 60-85 ℃, then beginning to dropwise add hydrogen peroxide, and controlling the temperature to be 80 +/-5 ℃ in the dropwise adding process; according to the theoretical amount, the amount ratio of the 2, 4-dinitroaniline to the hydrogen peroxide in the reaction kettle is 1: 0.52-0.8;
more specifically, the process of dripping hydrogen peroxide is controlled within 3-6 hours;
step B7: a high-temperature reaction process: after the dropwise addition of the hydrogen peroxide is finished, controlling the temperature to be 80 +/-5 ℃, carrying out heat preservation reaction for 1-2 hours, and entering a centrifugation process after the reaction is finished; or the reaction time takes the reaction end point of 6-bromo-2, 4-dinitroaniline with the content higher than 98.5 percent after sampling and centrifugal separation, and then the reaction enters a centrifugal process;
and step B8: a centrifugation step: after the heat preservation is finished, carrying out centrifugal separation on the reaction mixture to obtain a filter cake and a mother solution;
step B9: a drying procedure: after centrifugation, the filter cake is dried to obtain the product 6-bromo-2, 4-dinitroaniline, and the centrifuged mother liquor is recycled.
More specifically, in the steps B3-B7, the reaction kettle is in a stirring state.
Preferably, after suction filtration, the mother liquor is filtered and then sent to a recovery tank to replace hydrochloric acid for recycling. More specifically, after the mother liquor absorbs hydrogen chloride or is added with concentrated hydrochloric acid, the mass concentration calculated by HCl is 3% -10%, and the mother liquor is added into step B7 in the synthesis process instead of the concentrated hydrochloric acid for recycling.
Concentrations not mentioned in this patent document are mass concentrations.
The method for synthesizing the 6-bromo-2, 4-dinitroaniline by using the mother liquor is characterized by comprising the following steps: the 2, 4-dinitroaniline reacts with bromine added in a medium with the hydrochloric acid degree of 3% -10% to generate 6-bromo-2, 4-dinitroaniline and hydrogen bromide, then the temperature is raised, hydrogen bromide in the solution is oxidized into bromine by adding hydrogen peroxide, and the bromine and the unreacted 2, 4-dinitroaniline continue to perform bromination reaction. The change of the concentration of hydrochloric acid before and after the reaction is small, and the hydrogen peroxide is unstable and can be decomposed at high temperature, so that the solution after the reaction is only about 0.02 percent hydrogen peroxide.
The mother liquid contains trace unreacted 2, 4-dinitroaniline and 6-bromo-2, 4-dinitroaniline dissolved in acidic medium, 0.02% hydrogen peroxide and dilute hydrochloric acid, and hydrochloric acid does not react in the system. As water is generated in the reaction of hydrogen bromide and hydrogen peroxide, the acidity of the solution is reduced, and concentrated hydrochloric acid or HCl is required to be added to adjust the concentration of hydrochloric acid when the mother solution is recycled. Because the filter cake after centrifugation contains certain water, the water in the filter cake is removed by drying, and a small amount of hydrochloric acid can be supplemented after the mother liquor circulates for a certain batch, so that the mother liquor of the product can be completely recycled.
Under the condition of a dilute hydrochloric acid medium, 2, 4-dinitroaniline reacts with bromine to generate 6-bromo-2, 4-dinitroaniline and hydrogen bromide, after the bromine reacts, the temperature of a reaction kettle is raised, hydrogen peroxide is dropwise added, hydrogen bromide is oxidized into bromine by utilizing the oxidability of the hydrogen peroxide, and the bromine reacts with the unreacted 2, 4-dinitroaniline to perform bromination reaction. The process has the advantages that hydrochloric acid does not participate in the reaction, no hydrogen chloride is generated, the concentration of the hydrochloric acid cannot be increased, but water is generated in the reaction of hydrogen peroxide and hydrogen bromide, and the concentration of the hydrochloric acid can be reduced. The mother liquor of the product after reaction after centrifugation has no salt, the recycling of the mother liquor is not influenced, the concentration of hydrogen peroxide in the mother liquor is only 0.01-0.03 percent through detection, the content is very low, and the reutilization of the mother liquor has no influence on the reaction temperature.
The reaction principle is as follows:
these technical solutions, including the improved technical solution and the further improved technical solution, can also be combined or combined with each other, thereby achieving better technical effects.
By adopting the technical scheme, the invention has the following beneficial effects:
the synthesis method of 6-bromo-2, 4-dinitroaniline of the invention belongs to an environment-friendly production process, the product obtained by the process has high purity, the economic benefit is improved, the produced salt-free mother liquor is completely recycled, the zero discharge of wastewater is realized, the subsequent treatment cost is reduced, and the clean production is realized.
Detailed Description
The patent is further illustrated below with reference to examples. The scope of protection of the patent is not limited to the specific embodiments.
Example 1
In the synthesis method of 6-bromo-2, 4-dinitroaniline, 350 g of 2, 4-dinitroaniline with the content of 99.86% which is ground by a colloid mill, 200 ml of 31% hydrochloric acid and 1000 ml of water are added into a reaction kettle, the temperature is raised to 35 ℃, and the mixture is stirred for 1 hour.
Adding 150 g of bromine into the reaction kettle, and controlling the temperature to be 35-60 ℃ after the bromine is added for 40 minutes.
After the reaction is carried out for 1.5 hours under the condition of heat preservation, the temperature of the reaction kettle is raised to 80 +/-5 ℃, then 120 g of hydrogen peroxide with the concentration of 27.5 percent is dripped, the temperature is controlled to be 85 +/-5 ℃, after the dripping is finished for 4 hours, the reaction is carried out for 1 hour under the condition of heat preservation, 645 g of wet product and 1197 g of mother liquor are obtained by pumping filtration; oven drying to obtain 492 g of product with HPLC content of 98.6%, product yield 98.4%; the mother liquor contains 5.3 percent of hydrogen chloride by mass concentration and 0.013 percent of hydrogen peroxide by mass concentration; the mother liquor can be completely recycled as a reactant in the process of synthesizing 6-bromo-2, 4-dinitroaniline by adding 350 g of reaction raw material of 2, 4-dinitroaniline.
Example 2
A process for synthesizing 6-bromo-2, 4-dinitroaniline includes such steps as grinding 2, 4-dinitroaniline (99.86%) by colloid mill (350 g), separating mother liquid containing hydrogen chloride (5.3 wt.%), hydrogen peroxide (0.013 wt.%) and concentrated hydrochloric acid (3 g) (31 wt.%) in the reactor (3 g), heating to 35 deg.C, and stirring for 1 hr.
Adding 150 g of bromine into the reaction kettle, and controlling the temperature to be 35-60 ℃ after the bromine is added for 40 minutes.
After the reaction is carried out for 1.5 hours under the condition of heat preservation, the temperature of the reaction kettle is raised to 80 +/-5 ℃, then 120 g of hydrogen peroxide with the concentration of 27.5 percent is dripped, the temperature is controlled to 85 +/-5 ℃, after the dripping is finished for 4 hours, the reaction is carried out for 1 hour under the condition of heat preservation, 650 g of wet product is obtained by pumping filtration, 493 g of product with the HPLC content of 98.7 percent is obtained by drying, the product yield is 98.6 percent, and 1196 g of mother liquor with the mass concentration of 5.3 percent of hydrogen chloride and the concentration of 0.026 percent of hydrogen peroxide is obtained. The mother liquor can be completely recycled as a reactant in the process of synthesizing 6-bromo-2, 4-dinitroaniline by adding 350 g of reaction raw material of 2, 4-dinitroaniline.
Claims (9)
1. A method for synthesizing 6-bromo-2, 4-dinitroaniline is characterized by comprising the following steps: the method comprises the following steps:
step B1: mother liquor concentration blending process: adding hydrogen chloride or concentrated hydrochloric acid into the mother liquor, and adjusting the mass concentration of HCl to 3-10%;
the mother liquor comprises the following components: comprises 3 to 10 mass percent of hydrogen chloride, 0.01 to 0.03 mass percent of hydrogen peroxide, unreacted 2, 4-dinitroaniline dissolved in hydrochloric acid, and the balance of water and indispensable impurities;
step B2: grinding and material preparation: grinding 2, 4-dinitroaniline with the mass purity of more than 99.85 percent by a colloid mill, and adding the ground 2, 4-dinitroaniline into a reaction kettle;
step B3: adding mother liquor and hydrochloric acid: preferentially adding the mother liquor prepared in the step B1 into the reaction kettle, and adding hydrochloric acid and water when the mother liquor is insufficient, so that the final reaction kettle comprises the following raw materials: the concentration of the hydrochloric acid is 3% -10%, and the mass ratio of the 2, 4-dinitroaniline to the HCl substance is 1: 4-9; raising the temperature to 35-60 ℃, and stirring for 1-2 hours under heat preservation;
and step B4: adding bromine: adding bromine into the reaction kettle after the step B3 is finished, and controlling the temperature to be 35-60 ℃ in the dropwise adding process; so that the 2, 4-dinitroaniline and Br are added into the reaction kettle according to the theoretical amount2The mass ratio of the substances is 1: 0.51-0.52;
step B5: a low-temperature reaction process: after the bromine addition is finished, controlling the temperature to be 45 +/-5 ℃, and carrying out heat preservation reaction for 1-2.5 hours;
step B6: adding hydrogen peroxide: heating the temperature in the reaction kettle to 60-85 ℃, then beginning to dropwise add hydrogen peroxide, and controlling the temperature to be 80 +/-5 ℃ in the dropwise adding process; according to the theoretical amount, the amount ratio of the 2, 4-dinitroaniline to the hydrogen peroxide in the reaction kettle is 1: 0.52-0.8;
step B7: a high-temperature reaction process: after the dropwise addition of the hydrogen peroxide is finished, controlling the temperature to be 80 +/-5 ℃, carrying out heat preservation reaction for 1-2 hours, and entering a centrifugation process after the reaction is finished; or the reaction time takes the reaction end point of 6-bromo-2, 4-dinitroaniline with the content higher than 98.5 percent after sampling and centrifugal separation, and then the reaction enters a centrifugal process;
and step B8: a centrifugation step: after the heat preservation is finished, carrying out centrifugal separation on the reaction mixture to obtain a filter cake and a mother solution;
step B9: a drying procedure: after centrifugation, the filter cake is dried to obtain the product 6-bromo-2, 4-dinitroaniline, and the centrifuged mother liquor is recycled.
2. The method for synthesizing 6-bromo-2, 4-dinitroaniline according to claim 1, wherein: and B6, dropwise adding hydrogen peroxide, wherein the time is controlled to be 3-6 hours.
3. The method for synthesizing 6-bromo-2, 4-dinitroaniline according to claim 1, wherein: the hydrochloric acid concentration is 3% -10%, and the hydrochloric acid concentration does not include 2, 4-dinitroaniline.
4. The method for synthesizing 6-bromo-2, 4-dinitroaniline according to claim 1, wherein: and B3-B7, the reaction kettle is in a stirring state.
5. The method for synthesizing 6-bromo-2, 4-dinitroaniline according to claim 1, wherein: the bromine feeding temperature is controlled to be 35-60 ℃.
6. The method for synthesizing 6-bromo-2, 4-dinitroaniline according to claim 1, wherein: the mother liquor obtained in the following step A7 or the mother liquor obtained by recycling in the step B8 of the method is described:
step A1: grinding and material preparation: grinding 2, 4-dinitroaniline with the mass purity of more than 99.85 percent by a colloid mill, and adding the ground 2, 4-dinitroaniline into a reaction kettle;
step A2: a hydrochloric acid adding procedure: adding hydrochloric acid and water into a reaction kettle, raising the temperature to 35-60 ℃, and stirring for 1-2 hours under heat preservation; finally, controlling the concentration of hydrochloric acid to be 3% -10%, wherein the quantity ratio of 2, 4-dinitroaniline to HCl is 1: 4-9;
step A3: adding bromine: adding bromine into a reaction kettle, and controlling the temperature to be 35-60 ℃ in the dropwise adding process; the mass ratio of the 2, 4-dinitroaniline to the bromine substance is 1: 0.51-0.52;
step A4: a low-temperature reaction process: after the bromine addition is finished, controlling the temperature to be 45 +/-5 ℃, and carrying out heat preservation reaction for 1-2.5 hours;
step A5: adding hydrogen peroxide: raising the temperature in the reaction kettle to 60-85 ℃, then beginning to dropwise add hydrogen peroxide, controlling the temperature to be 80 +/-5 ℃ in the dropwise adding process, wherein the mass ratio of the 2, 4-dinitroaniline to the hydrogen peroxide is 1: 0.52-0.8;
step A6: a high-temperature reaction process: after the dropwise addition of the hydrogen peroxide is finished, controlling the temperature to be 80 +/-5 ℃, carrying out heat preservation reaction for 1-2 hours or controlling the content of 6-bromo-2, 4-dinitroaniline to be higher than 98%, and entering a centrifugation process after the reaction is finished;
step A7: a centrifugation step: after the heat preservation is finished, carrying out centrifugation or suction filtration separation on the reaction mixture to obtain a filter cake and a mother liquor;
step A8: a drying procedure: after separation, the filter cake is dried to obtain the product 6-bromo-2, 4-dinitroaniline.
7. The method for synthesizing 6-bromo-2, 4-dinitroaniline according to claim 6, wherein: and D, filtering the mother liquor separated in the step A7, and then sending the filtered mother liquor into a recovery tank to replace hydrochloric acid for recycling.
8. The method for synthesizing 6-bromo-2, 4-dinitroaniline according to claim 6, wherein: step A2-step A6, the reaction kettle is in a stirring state.
9. The method for synthesizing 6-bromo-2, 4-dinitroaniline according to claim 6, wherein: and step A5, dropwise adding hydrogen peroxide, wherein the time is controlled to be 3-6 hours.
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|---|---|---|---|---|
| CN112321439A (en) * | 2020-10-15 | 2021-02-05 | 浙江迪邦化工有限公司 | Method for high-pressure assisted synthesis of 6-chloro-2, 4-dinitroaniline |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103787891A (en) * | 2014-01-23 | 2014-05-14 | 安徽华润涂料有限公司 | Production technology of synthesizing 6-bromo-2,4-dinitroaniline |
| CN104447357A (en) * | 2015-01-07 | 2015-03-25 | 山东昌邑灶户盐化有限公司 | Method for preparing 2, 4-dinitro-6-bromoaniline through two stages of oxybromination |
| CN108191672A (en) * | 2017-12-19 | 2018-06-22 | 浙江龙盛集团股份有限公司 | A kind of synthetic method of 2,4- dinitros -6- chloroanilines |
-
2019
- 2019-12-30 CN CN201911393067.5A patent/CN111170871A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103787891A (en) * | 2014-01-23 | 2014-05-14 | 安徽华润涂料有限公司 | Production technology of synthesizing 6-bromo-2,4-dinitroaniline |
| CN104447357A (en) * | 2015-01-07 | 2015-03-25 | 山东昌邑灶户盐化有限公司 | Method for preparing 2, 4-dinitro-6-bromoaniline through two stages of oxybromination |
| CN108191672A (en) * | 2017-12-19 | 2018-06-22 | 浙江龙盛集团股份有限公司 | A kind of synthetic method of 2,4- dinitros -6- chloroanilines |
Non-Patent Citations (1)
| Title |
|---|
| ANDRIEVSKY, A.M. ETAL.: ""Bromination of deactivated aromatic compounds"", 《RUSSIAN CHEMICAL REVIEWS》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112321439A (en) * | 2020-10-15 | 2021-02-05 | 浙江迪邦化工有限公司 | Method for high-pressure assisted synthesis of 6-chloro-2, 4-dinitroaniline |
| CN112321439B (en) * | 2020-10-15 | 2022-08-05 | 浙江迪邦化工有限公司 | Method for high-pressure assisted synthesis of 6-chloro-2, 4-dinitroaniline |
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